196 111 342MB
English Pages 240 Year 2020
GLOBAL FIRE SAFETY ISSUES:
INDUSTRIES AND PRODUCTS
FIRE RETARDANT CHEMICALS ASSOCIATION
Papers Presented At:
ROYAL SONESTA HOTEL
NEW ORLEANS, LOUISIANA
MARCH 14-17,1999
INFORMATION ACCURACY CAVEAT
The presentations in this publication are believed to be correct and accurate. However, the views, comments, conclusions, and data of the authors are their own and do not necessarily reflect the policies or opinions of the Fire Retardant Chemicals Association. The Fire Retardant Chemicals Association is not responsible for errors, inaccuracies, or opinions in the presentation nor any damages that might be incurred by any company due to incorrect information contained in any of these presentations.
GLOBAL FIRE SAFETY ISSUES: INDUSTRIES AND PRODUCTS 1999 SPRING INTERNATIONAL CONFERENCE FIRE RETARDANT CHEMICALS ASSOCIATION TABLE OF CONTENTS "FiRe-LCA Status Report 1998" M. Simonson P. Blomqvist A. Boldizar C. Tullin H. Stripple J. O. Sundqvist
Swedish National Testing and Research Institute
"New Flame-Retarding Plastics without Halogen and Phosphorus for Electronic Products" M.lji S. Serizawa Y. Kiuchi
NEC Corporation
''Action toward Plastic Recycle: From Plastic Material Selection to Collection and Recycle" M. Tokuse
RICOH Co. Ltd.
"Toxicity Studies Concerning Antimony Oxide" A. P. A. G. Francis
Campine
"Implications for Flame Retardants in the Development of a Single Source Code in the U.S." R. S. Strength
FRCA Code Consultant
"Harmonisation of the Testing of European Construction Products: The Final Quarter" D. L. Buszard
FMC Corporation
"Zinc-Sulfide-Based Flame-Retardant Systems" Th. Uhlenbroich Sachtleben Chemie GmbH
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19
27
49
55
73
77
"Polymeric Materials in Portable Electric Appliances" W. H. King, Jr. U.S. Consumer Product Safety Commission
95
"The Study of Nonhalogen Flame Retardant Systems for Wire and Cable" H. Nishizawa M. Dkoshi Showa Electric Wire and Cable Co. Ltd.
103
"Melamine Based Flame Retardants-A Fresh Look" R. Grabner DSM Melapur
117
"New Developments with Phosphorus-Based Flame Retardants for Engineering Plastics, Polypropylene, and Thermoset Resins" S. Hoerold W. Wanzke Clariant GmbH D.Scharf Clariant USA
129
"Fires in the Home" R. A. Graham The Alliance for Consumer Fire Safety in Europe
155
"Fire Retardant Reagent in the Composite Board Industry" D. Galsworthy A.D.1. Technical Applications J. Voortmans F-Stop
163
"Bromine-Free Flame Retardant Polycarbonate" A. Nodera Idemitsu Petrochemical Co., Ltd.
177
"The Role of Flame Retardants in E&E Equipment" J. H. Troitzsch Fire & Environment Protection Services
191
"Thermal Stability of Brominated Additives for Engineering Plastics Applications" A. Hochberg Amaranth Technology, Inc.
199
The following paper from the Newport, Rhode Island, Fall 1998 conference is also included in this proceedings. This paper was not part of the preprint which was available at the meeting.
"Fire Prevention through Fire Retardants for Electrical Applications" A. Tewarson
Factory Mutual Research Corporation
207
Margaret Simonson, Per Blomqvist, Antal Boldizar and
Claes Tullin (SP)
Hikan Stripple and Jan Olov Sundqvist (IVL)
FiRe-LeA Status Report 1998
0
SP Swedish National Testing and Research Institute Fire Technology SP Work Report 1998:40
cB
CRC Press Tay lor & Francis Group Boca Ratan London New York
CRC Press is an imprint of th e Tay lor & Francis Group, an informa business
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CRC Press Taylor & Francis Group 6000 Broken Sound Parkway NW, Suite 300 Boca Raton, FL 33487-2742 © 1999 by Taylor & Francis Group, LLC CRC Press is an imprint of Taylor & Francis Group, an Informa business No claim to original U.S. Government works This book contains information obtained from authentic and highly regarded sources. Reasonable efforts have been made to publish reliable data and information, but the author and publisher cannot assume responsibility for the validity of all materials or the consequences of their use. The authors and publishers have attempted to trace the copyright holders of all material reproduced in this publication and apologize to copyright holders if permission to publish in this form has not been obtained. If any copyright material has not been acknowledged please write and let us know so we may rectify in any future reprint. Except as permitted under U.S. Copyright Law, no part of this book may be reprinted, reproduced, transmitted, or utilized in any form by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying, microfilming, and recording, or in any information storage or retrieval system, without written permission from the publishers. For permission to photocopy or use material electronically from this work, please access www. copyright.com (http://www.copyright.com/) or contact the Copyright Clearance Center, Inc. (CCC), 222 Rosewood Drive, Danvers, MA 01923, 978-750-8400. CCC is a not-for-profit organization that provides licenses and registration for a variety of users. For organizations that have been granted a photocopy license by the CCC, a separate system of payment has been arranged. Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation without intent to infringe. Visit the Taylor & Francis Web site at http://www.taylorandfrancis.com and the CRC Press Web site at http://www.crcpress.com
Executive Summary The preliminary results from the work conducted in 1998 as a part of the FiRe-LCA TV Case Study are contained in this report. The experimental results presented include Cone Calorimeter analyses of FR and NFR TV backplates and US and Swedish TV PWBs. These results show that the FR material produces more products of incomplete combustion per mass unit of material burned. These results are specific for this test method and cannot be directly extrapolated to large scale fire behaviour. Further, preliminary results from fire experiments on full TVs are presented. These results will provide input to the LCA model once full chemical analyses are available. The LCA model requires large amounts of input data that has been partially collected in this first phase of the TV Case Study. The available information is summarised and remaining work outlined. The recycling work has been somewhat delayed but information is presented concerning the planned work based on developments in the latter part of 1998, and timing for 1999. It is anticipated that full results for this part of the TV Case Study will be completed by late February, 1999. Work underway is presented for both the Incineration and Landfill part of the TV Case Study. The Incineration work has turned up some interesting information concerning full scale work that has been done locally concerr :.,g the effect of the addition of large amounts of TV backplates to the fuel stream of a waste combustor in Goteborg. Investigation of this work will continue. Finally, two draft articles are included as appendices. The first concerns interpretation of fire statistics concerning burning TVs throughout Europe and North America. The second is a presentation of the LCA straw model accepted for the Interflam '99 conference to be held in Scotland mid-1999.
KEY WORDS: Flame retardant, fire, LCA, recycling,landfill
Sveriges Provnings- och Forskningsinstitut
Swedish National Testing and Research Institute
SP Arbetsrapport 1998:40 ISBN 91-7848-731-5. ISSN 0284-5172 Bods 1998
SP Work Report 1998:40
Postal address: PO Box 857, SE-SOIlS BoRAs, Sweden Telephone +4633 165000 Telex 36252 Testing S Telefax +46 33 135502
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1
Introduction
The FiRe-LCA project officially started in September 1998 after completion of a Preparatory Study where a straw LCA model was defined, both in general terms and for the specific case studies included in the project. This report contains information concerning the work that has been completed in the latter part of 1998 within this project. This report should be considered an internal project document and should not be released to the general public prior to its discussion at the next project meeting, January 261\ 1999.
2
Fire Statistics
A large body of fire statistics are available world-wide concerning fires in audio-visual equipment. A great deal of these statistics had been collected by EBFRIP as a part of their previous project concerning TV fires and flammability. This material has been given to Margaret Simonson and provides the basis for the TV Fire Statistics article given in Appendix 1. The statistics available at the start of this project have been supplemented by material in Swedish and by interviews with Swedish officials from the Swedish Electrical Commission. In general the results show that a figure of approximately 100 TV s/million bum in Europe each year due to internal ignition sources and a further 65 TV s/million due to external sources. The distribution according to size of the fire is based on German results summarised in Table 2.1. Table 2.1: Severity of TV set fires in Germany r-'
Severity Fire restricted to the TV
Fire spread beyond the TV and causing damage to the property Fire causing severe damage to the ~om and property Fire causing major damage to the entire dwelling Fire completely destroying the building
Frequency(% ) 30-40
% used in model 35
Category in LCA model minor
40-60
53
full TV
1994 RICOH Co., LTD... Based on an unique concept named "Comet Circle TM". Ricob is tackling with construction of actual system for recycle.
This Comet Circle is the basic concept of our product recycle. Please compare it with the explanation made in the previous slide. In the case of plastics, from oil extraction, monomer processing, polymer processing, molding plant, manufacturing plant, sale, user, then to collection cent er and recycle cent er, and further through the above mentioned polymer processing, it circulates again to the molding plant. It used to become shredder dust. There was no recycling.
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Plastic material selection/Point table
In case of MA" kind of plutic
eo.pan, a. ba••
A
•
C
D
E
5
4
5
3
2
2
4
1 0 5 5 1 0 35 1 0
7 4 5 1 0 30 1 0
1 0 3 5 6 29 9
1 0 3 5 9 30 9
5 4 5 8 24 5
7 4 5 1 0 28 8
5 5 7 30 8
5 5 5 5 30 65
5 5 5 5 30 60
3 4 3 4 23 52
3 5 5 5 27 57
3 2 2 2 1 4 38
4 3 3 3
Allot ment Material Evalu.tion
Company evaluation
Ba.ie eharaeteri.tiel Moldability Reeyclability LicbtpraoC Price (.ub total) Corrupondence to environment Technical .upport Ovene.. purcha.e Trade" loci.tica Prolpect in the future (.ub total)
Gra.. total
~,-
0
A••ip
0
2 1 49
9
5 3 4 5 25 55
0
"B"Company is evaluated for its possibility of overseas purchase "E"Company is evaluated for its acquisition of 18014001 certification and technical support. 7
The reason of showing this table to you is this. In the past. material selection used to be made only on the basis of basic characteristics. moldability. lightproof and cost of material evaluation. Since 1993. as you see in the table. software area of recyclability(heat history). correspondence to the environment. technical support including recycle, and overseas purchasing are also evaluated. The table is to prove this. Material evaluation is weighed 35 and company evaluation is weighted 30. It ranges from 38 to 60 in the full marks of 65. I wanted to report to you that such evaluation has started.
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Level Up of Recycle Design Policies
Focusing on strong needs or recycle design subjects -Open loop material recycle -Reduction or package use and its reutilization
Corresponding to all recycling treatments -Reuse or products and parts -Closed loop material recycle -Chemical recycle Energy recovery
Level up or each recycle design items -Addition or new items in initial recycling operation -Reflection or DAM regulations, etc.
and
D
Level up or each recycle design items -Addition of new items in full scale recycle operation
-Corresponding regulatioDS,etc
le
The design for recycle has started in May, 1993. The level 1 highlighted correspondence to packaging material. The level 2 became aware of material recycle. And the level 3 stressed reuse. Further, every 1 -- 2 years, the design policy is upgraded in correspondence to feedback from inner and outer functions and social trend such as WEEE.
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8
Material rates in PPC(wt.)
Copper
5%
Plastics (exterior)
Others
10%
10%
Plastics (others)
10%
Alminum
6%
Steel 59% 9
So that Ricoh's products and recycling are further known to
you in detail, please examine material constitution, ~ by
weight of dry copier(PPC), Ricoh's main product. Metals
share 70% by weight. Recyclability of plastics of 20% is key
to improvement of recycle ratio.
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Closed loop material recycle of plastics
This slide shows life cycle of plastic. The life used to be 'Starting from Production of oil and ending with Disposal. • At Ricoh. simple shredding in product recycling is entirely abandoned. Instead. we combine manual dismantling and machinery shredding and conduct dismantle and separation. As the result of adoption of this system. plastic recycle has become feasible. Collected plastics are reborn in 'Compounding' process.
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Conditions to realize closed loop material recycle of plastics eTo secure the quantity of materials to be utilized eTo secure the usage of reutilized materials eTo assure quality of reutilized materials .To secure economics 11
In order to conduct plastic recycle, we consider 4 items written here important. *To *To * To * To
secure secure assure secure
the quantity of materials to be utilized,
the usage of reutilized materials,
quality of reutilized materials, economics.
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Plastics part with grade number displayed
12
Plastic Jm1;s used far ruter cover IIBterial are decided to be displayed with IIBterial rare grade IlCIre of resin 1IBker. To krow wOO what of the ca.nteqmt is the first entrarx:e of IIBterial recycle.
cm
am
38
r.
Inserted Decal
I
This is an example of recyclable product design. To remove different object or different material attached to the plastic parts is an important process of recycle. In this picture, simply detachable operation instruction part is devised in the design stage.
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Pulverizing and Metal detecting process Pulverizer
Belt conveyer
Metal detector
This picture shows a part of recycle process we are using experimentally. We have learnt a lot from this equipment. In February, 1999, our unique devices have also been developed to realize energy-saving, low noise and little dust. These devices will, in the near future, operate in all recycle centers associated with Ricoh. The devices are named '" COP S "', meaning Comet-Circle of Plastic System.
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Amount of energy consumption
Reoyelin, T o t a l _
of ,.00".,.4 m.t.n.1 inc/Sortina/Puverizin,
t
IiiII
T.... port of oo.r
•• •o e CL
NOII-l'eC)'cliD& TocaI
~
D •• po ••'
T,.,aport of copier
l~af"""l
,
... ~~
Production of poiyme Production of 01
o
,
~
10
20
30
40
50
eo
70
IS
From this slide. I will introduce the life cycle assessment of our study. Until "'Non-recycling Total * from the bottom. the "'Energy Consumption'" from conventional oil extraction to landfill after shredding is shown. Up above it, we have "'Recycling Total", showing the "'Energy Consumption" required for the recycle of our system.
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Amount of C02 emission
Reoyo",Tot.1 Tf'8n..,-t. of reooverM mete';.' Di..... mbin&/Sortin&lPuv.rizin •
••
1
Di.po..'
T,..,..iIPO"t .t copier
Prooduotion
IIII!I• • • • • • • • • • • • • • • • • • • •
Ofpotvm.,. . .
Prooduotion~~I~==~~==~~~~===7.~==~~==~~==~====~====~ o 500 1000 1500 2000 2500 3000 3500 4000 4500
• 16
This slide shows wC02 emission w under the same idea.
42
Po
Effect of recycling Energy consumption
....
MJ
1• .000
_
... ...
E...,., ••".w......._
,
10Cla
H .O
4100
....
-+-oR._atl... ,.te
...
C02 emission
•
11
_
.....
11
....
....
C02 ."II..lon
-.-R .duclto" rat•
4000
lI.'
1100
It .•
H .O
JOOO
I'.'
" .0
.100
••••
ao.OH
....
'O.DOI
I • .'
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a•.•
H .O
1000
I • .•
'I.'
lOO
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-
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..
.
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JO,
..,
,oot
•.
.... ,1ItN ., , ......." • • • ri..
....
1000
0
0.
,0.
JOI
101
100'
17
This slide shows "Energy Consumption" required for making plastics and also shows plastic recycle for each mixture ratio. 0% is when 100% pure virgin material is used. 100% is when only plastics collected from the market are reutilized. Practically, due to other concerns, it should be reasonable to mix 20.......30% collected plastics. When 30% is mixed, we obtain about 30% energy consumption. In the case of C02, we get about the same trend. From the standpoint of life cycle assessment, we get such conclusion. Further, what we should remember is that we get resource saving, too.
43
...
Test report on the horizontal material recycle -From outer packqinl materials to outer packqinl materials
LI1it
CD
Specific Gravity Kgl0n2 CID Tensile Strength @ Tensile 801'lption Kglan2 @ Aexural Strength Kglan2 @ lzod IrrplCt Kg-anlan CC ® I-DT(heat distortion TerJl)Eftture)
(J) M=1 ® UL..94
gl10nin
Virgin(100) 1.17 370 ffiO 24,:m 17 ffi
V[lO): C(~ 1.17 370 ffiO 24,200 17 ffi
V(O) : C(100) 1.17 300 640 23,200 18 ffi
36
39
45
22Onm5VB
22Onm5VB
22Onm5VB
l.00nmv-o l.00nmv-o l.00nmv-o >ABS-FR
YES
+
YES
(YfrPI ".IMIOI CoIoo....
_->
IIo_
3 . R-..I .....IIo(Other _YES 4. R - - ' ..... YES
YES YES
YES
YES
YES
5mm
YES
YES
YES
5mm
YES YES
YES YES
YES YES
5mm 5mm
cood
pade and color..,.. IInihd
In d.al", and production ata,.a, the r.cycl. coat much hllher than purchu. prlc. would be Incurr.d at recycll"- at.p.
Reuon: The condltiona of relativ.ly
.fflcl.nt mat.rlal recycl. would not be met. and the r.ault la coatly poor
incineration or IandfiIL
In this slide, I will report on our activities for realization of recycle we are conducting now. Detailed explanation is omitted.
46
Conclusion: Aiming cyclic economics society,
Consensus should be formed for -Methods of usage and treatment of plastics
Safety in use
1 . Flame retardation 2. Endocrine disrupter
[ Development of safe raw materials 1 •Dioxin and others
J
/
~LASTIC0
I'
"
Easi~~ recycle
1. Minimization of types of
used materials
2. Devolopment of th.
design for easier dismantlinl '- and separation
./
Construction of international recycle network 1 . Cross industry recycle facilities
2. Database for plastic reutilization
21
The above explanation is on plastic recycle activities in Japanese market. It must be difficult task to extend it to the world markets. In closing my speech, however, I will point out 4 items which every participant should tackle with, right from now.
1. Development of safe raw materials Dioxin is a big issue. Flame retardant industry has developed non-decabrOllinated type instead of Such effort is desired. Possible maxilllUll infol'll8tion disclosure is also decabrominated type. desired. 2. Safety during use For our products, the maximum flame retardation is required. It is 5V, VO class of UL94. This is an absolute necessity in introducing our products to the market. It cannot be omitted. On top of it, endocrine disrupter should never be emitted from heat during use. Further study will be required. 3. Easier recycle It is the responsibility which we, equipment manufacturers should assume. Design for easier recycle is a must in product manufacturing in the future. Though I did not mention this tilDe, it is the best method to achieve compatibility of economics and environment in recycle. 4. International recycle network I wanted to speak about networking in various meanings; but I do not have time. I think the contents of my speech today are the first step toward networking for the future. Lastly, people tend to journalistically combine ·plastics, dioxin and endocrine disrupter·. But I am inforated that steady studies are being carried out on hazardousness and on the means not to generate ·hazardous substances· (Material recycle is considered one of those means.) in each step of 1) Production stage, 2) Use stage, 3) Recycle and Disposal stage. I hope such infol'll8tion will positively be disclosed from the people gathering here and that such efforts are made continuously in the future, too. Ricoh will also continue such research and development. I would like to express my sincere appreciation for being given today's opportunity of speech and for your listening to me. Thank you!
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TOXICITY STUDIES CONCERNING ANTIMONY OXIDE LITERATURE REVIEW ON THE HAzARDS TO MAN AND THE
ENVIRONMENT OF ANTIMONY OXIDES USED IN FLAME RETARDANTS
AND OTHER ANTIMONY COMPOUNDS
Dr. Agna P.A.G. Francis
Campine
I. INTRODUCTION In recent years the public has perceived a broader concept of product fire safety. This new understanding has led to reconsideration of the overall fire safety of commercial buildings and furnishing materials. In this context fire retardants are most frequently being used and added mainly to plastics in order to reduce their burning rate. For fire retardant products in particular, the question has been raised as to (a) whether the additives effect a trade-off between decreased burning and increased emission of toxic gas species (smoke), (b) whether there is a net safety benefit from the use of fire retardant. Most often synergists of which antimony trioxide (SbzO) is the most effective and widely-used, are added to halogenated flame retarded polymer formulations in order to decrease the use ofhalogenated compounds. Recently the use of antimony oxides as a synergist to halogenated flame retardants in plastics, textiles and other products have been questioned since antimony compounds are being suspected to contain environmental and human health risks. In order to identify, compile and sometimes clarify misinterpreted information existing on the subject of antimony oxides the University of Ghent in collaboration with ET&C was approached by Campine to evaluate critically the existing literature on the hazard of antimony oxides. This literature review, based on 148 references and completed in July 1998, is intended to characterise the risks to man and environment associated with the use of antimony compounds and antimony oxides in particular. This report contains updated information on health effects of antimony oxides in animals and humans following inhalation, dermal and oral exposure. The different topics discussed are toxicokinetics, general toxicity, genotoxicity, carcinogenicity, reproduction effects, SIDS and combustion. It also covers the possible environmental impact which antimony oxides can have after release in the environment. Apart from this review the results based on studies concerning general toxicity and genotoxicity performed by APME in 1998 were included in this lecture. 11. ECOTOXICOLOGICAL ASPECTS In general the information on the effects of antimony oxides on both aquatic and terrestrial organisms is scarce and characterised by a large variability in concentrations-effect relationships. Because of the low solubility of antimony trioxide most toxicity data were generated with antimony chlorides. The generated toxicity data for antimony oxides could not lead to the introduction of threshold values. No ecotoxicity data were found for terrestrial organisms while the acute toxicity (=LCso) of antimony (III) to several freshwater 49
species did not occur below the limits of solubility of the antimony salts. From the available data concerning the chronic toxicity of antimony (ID) to aquatic animals it can be concluded that the most sensitive effect was seen for the growth of juveniles, but no significant reduction in survival or growth was observed at 1130 ~gIl. Based on the available aquatic toxicity data an indicative maximum permissible
concentration for antimony in water, expressed as Sb2C13, could be established at
5 ~gIl. Considering the antimony concentration in (Dutch) surface waters between 1 to 3 ~g/l, one can conclude that it is unlikely that antimony causes any harmful effect on the aquatic ecosystem. In addition several studies have demonstrated that antimony has a low to moderate potential for bioaccumulation in both freshwater and marine species. In literature average bioconcentration factors (BCF) for antimony are known for various species. Based on these data it can be concluded that the bioaccumulation potential, describing the transfer of contaminants from the external environment to an organism, is only moderate. Moreover, since the data concerning the occurrence of antimony in the environment suggest that antimony is only present in low concentrations, it can be concluded that biomagnification, expressing the transfer of contaminants through the food chain in higher organisms, will not occur.
m. TOXICOKINETICS Toxicokinetical studies follow the route of absorption, distribution, biotransformation and elimination/excretion of a product both in animals and humans. The toxicokinetics database dealing with the disposition of antimony and antimony compounds in animals and humans is patchy. Dermal, inhalation and oral exposure in ANIMALS: For animals no data are available concerning the uptake of antimony following dermal exposure. Via inhalation Sb20 3 is poorly absorbed in function of particle size, with most antimony being retained in the lung. The bigger particles were deposited in the upper respiratory tract and they were cleared after several hours via the mucociliary system. The smaller particles, which were deposited in the deeper parts of the lung were absorbed slowly after several weeks. Once absorbed a retention of Sb(III) in red blood cells and a wide spread distribution in different parts with following decreasing Sb content is observed: spleen> liver> kidney> brain> femur. Sb excretion occurs mainly via the urine and faeces, depending on the chemical form: Sb(III) is mainly excreted via faeces while Sb(V) is mainly excreted via urine. Absorption of antimony metal, Sb20 3, Sb2S3 and SbCl3 by the oral route has been demonstrated but no significant accumulation seems to occur. Once absorbed it undergoes a wide spread distribution over liver > spleen > kidney > heart > lungs > muscle. There was an important retention of Sb in the thyroid following exposure to Sb20 3, while retention of Sb in red blood cells was observed following SbCl3 exposure. Antimony absorbed from the gastrointestinal tract appears also to be excreted in the urine and faeces to a variable degree as explained before. Dermal, inhalation and oral exposure in HUMANS: As for animals there are no data available on absorption, distribution or elimination caused by dermal exposure in humans. Toxicokinetic data from studies in humans are in general very limited and mostly related to inhalation exposure in an occupational setting. Antimony is retained in the lung for a long period of several years. Absorption of antimony by this route has been demonstrated for Sb metal, Sb20 3, Sb2S3 and SbCI3, but little is known about the distribution of the absorbed fraction. In case of intravenous (IV) injections with antimony preparations, the 50
highest levels were found in the liver, heart, kidneys and thyroid. Elimination of absorbed antimony occurs mainly via the urine or the bile, depending on the valence state. Other potential routes of elimination have not been investigated. There is no data available on the oral exposure of humans to antimony oxides. Biliary excretion of Sb was observed following ingestion of Sb2Sl . Also in this case it was concluded that Sb(III) is mainly excreted in the faeces and to a lesser extent in the urine. As opposed to As, methylated Sb could not be detected in the urine after ingestion of Sb2Sl · IV. GENERAL TOXICITY The general toxicity of antimony and antimony compounds following single or repeated (continuous) exposure has been reviewed extensively in this study both for animals and humans. General toxicity in ANIMALS: Concerning the effects of single exposure of animals to antimony oxides, it could be concluded that Sb20 l is of low acute toxicity by the oral, dermal and intraperitoneal route. No data were available for inhalation exposure. Antimony oxides did not cause skin irritation in animal studies. However, they were severely irritating to the eye. Antimony oxides showed a response in poorly conducted sensitisation studies, but no conclusions could be drawn from the results obtained due to co-exposure to a known skin sensitiser. No evidence of sensitisation was seen in adequate studies. The effects of repeated or continuous exposure of animals to antimony oxides have been in general poorly conducted. Following inhalation exposures the principal effects of repeated inhalation exposure of Sb20 l have been seen in the lungs. Interstitial fibrosis has been found with varying degrees of severity in rats, rabbits and swine following exposure for 12-14.5 months to Sb20 l at levels ranging between 1.6 and 104 mg Sb/ml. As known the maximum accepted level on the workfloor is 0.5 mg Sb/ml. Based on oral exposure to Sb20 l the following details can be reported based on the study performed by APME. After an oral feed during 28 days the pathological no-effect level was 5000 ppm Sb20 l . Another study reports no deaths after a 30 days exposure to a level of 0-1070 mglkg/day, only an increase in red blood cells. After 90 days with dosing from 0 to 20000 ppm Sb20 l no adverse effects on body weight, food consumption, histology or heamatologicallclinical observation parameters were observed. Conclusion was that Sb20 l has an extremely low toxicity, the LDso is much higher than the maximum achievable dosing level of 28 glkg. General toxicity in HUMANS: Concerning the effects of single exposure of humans to antimony oxides, it could be concluded that no information is available on the systemic effects arising from single inhalation or dermal exposures. The results of irritation and sensitisation studies in humans show that antimony trioxide can cause skin lesions known as 'antimony spots'. However, it is not clear if many of the skin lesions reported among antimony workers were attributable to an irritant or sensitisation reaction. What the effects of repeated or continuous exposure of humans to antimony oxides is concerned most studies are inadequate and difficult to interpret because of mixed exposures and the absence of control groups. Other than the skin lesions found in workers handling Sb20 l , there is no information on the effects of repeated dermal exposure. Nor were data found on effects of repeated oral exposure. However, consistent effects likely to be caused by antimony or antimony compounds were seen 51
across several studies involving effects on the respiratory tract. Symptoms relating to respiratory tract inflammation were commonly reported. Other symptoms, reported less frequently, in exposed workers were conjunctivitis and gastro-intestinal disturbances. Only one study showed alterations in ECG.
v. GENOTOXICITY Genotoxicity is defined as the ability to damage DNA and to change DNA sequence. DNA sequence changes can be single nucleotide changes that result in point mutations, or multiple nucleotide changes that result in visible chromosomal aberrations. The adverse effect of a mutation is dependent on the gene and the tissue affected. Literature has been screened to look for the genotoxic potential of antimony and antimony compounds. On the basis of the positive results obtained in bone marrow cytogenetics studies, both Sb20 l and SbCIl could be regarded as genotoxic in vivo. Supportive positive data have also been obtained for these compounds in vitro, although this area has not been well studied and contradicting results have been obtained. With Sb20 l no increases in reverent numbers in Salmonella typhimurium and Escherichia coli tester strains were seen, while in the rec assay with Bacillus subtilis a clear DNA damaging activity was observed. According to the authors this could be explained by the fact that the cell wall of S. typhimurium (Gram-negative bacteria) is less permeable to Sb20 l than that of B. subtilis (Gram-positive bacteria). However, SCE (Sister Chromatid Exchange) tests with human lymphocytes in vitro indicated that Sb20 3 showed a slightly higher genotoxicity than SbCI3• The APME study performed in 1998 indicated that although Sb20 l shows in vitro clastogenic activity, it is not an in vivo genotoxic and therefore does not pose any genotoxic hazard to man.
VI. CARCINOGENICITY In this part the information gathered on carcinogenicity, meaning the ability to induce or enhance neoplastic diseases, is summarised. Carcinogenicity in ANIMALS: About the carcinogenicity of antimony in animals it can be concluded that there are no bioassays conducted to modem regulatory standards available for any antimony compound. Both Sb20 l and Sb2Sl or concentrate have produced tumours in rat lungs after a one-year exposure period by the inhalation route. The study of Groth (1986) showed the presence of lung neoplasms in 27% of females exposed to Sb20 l • Watt (1983) induced lung tumours in rats with lower concentrations and a NOAEL (No Observed Adverse Effect Level) of 4 mg Sb/ml has been identified for Sb20 3• However, it is not clear if tumours would have developed at the lower dose levels tested had rats been exposed for the two years required for modem regulatory bioassays, a reason why this NOAEL may not accurately reflect the true activity of Sb20 3 • Other studies such as the Bio/dynamics study (1990) did not observe lung tumours, notwithstanding the fact that similar concentrations had been used as in the study performed by Watt. A possible explanation for these conflicting results could be the differences in the amount of antimony that was deposited in the lungs. This hypothesis is based on the histopathology examination perfonned on the slides from the both studies. It was clear that the degree of pigmentation in the lungs was greater in the lungs of rats from the Watt study compared to those from the Bio/dynamics 52
study. The mechanism for induction of the lung tumours is unclear. The carcinogenicity of inhaled antimony is probably related to its deposition in the respiratory tract and the resulting reactive processes induced by its presence in the lung tissue. This deposition and clearance of antimony depends on particle size. Antimony with small particle sizes comes into contact with the lung tissue for a longer period of time which may influence the carcinogenicity. The positive results from the Watt and Groth study can also be explained because of a higher lung burden. It was demonstrated that, at excessive lung burdens, clearance rate of insoluble particles from rat lungs is reduced. Thus, there could be a 'foreign body' neoplastic effect in overloaded rat lungs resulting from the prolonged contact with the non cleared particles. Concerning carcinogenicity data for oral or dermal exposures to Sb20 3 are Sb2S3, no data are available. Carcinogenicity in HUMANS: All data following exposure of antimony and antimony compounds in humans are inconclusive. The three studies available, in which some evidence of an increased incidence of lung cancer was obtained, were entirely inconclusive as in all cases, workers were also exposed to arsenic, a known human carcinogen.
VII. REPRODUCTION AND DEVELOPMENT EFFECTS Concerning reproduction no toxicity studies of acceptable quality are available. Therefore it can be concluded that the reproductive toxicity of antimony and antimony compounds has been inadequately investigated. About developmental effects, it is not possible to draw any conclusions from the poorly conducted and reported studies available.
VIII. SIDS In the past the relation of antimony compounds to Sudden Infant Death Syndrome (SIDS) has been a point of discussion based on the study from B.A. Richardson. The LGCIIMI study found no evidence to substantiate the claim from Richardson that micro organisms present on cot mattresses and covers produce toxic gases from antimony compounds present on the mattresses and covers. No evidence could be found for the production, in culture, of methylated antimony compounds from water-insoluble or soluble antimony derivatives by the aerobes S. brevicaulis or Bacillus sp., or by anaerobes associated with cot mattress materials. Therefore the Expert Working Group came to the following statement. In view of the lack of any independent supporting data, together with concerns about the suitability of B.A. Richardson's detection techniques and laboratory conditions, and the lack of any significant changes in the rate of SIDS over time, it can be concluded that the hypothesis relating SIDS with microbial infestation and gas generation from antimony and phosphorus based additives, such as fire retardants, present in cot furnishings is unfounded.
IX. COMBUSTION The possible environmental effects and/or human health risks when consumer products enriched with antimony oxides are involved in fires, were looked at based on
the available combustion studies. No conclusions can be drawn as no antimony 53
concentrations were measured in the gaseous phase or the soot/char residues. Elevated concentrations of antimony were measured in the soot deposits originating from people who perished in fires, indicating that exposure to antimony following inhalation can occur during fires. The possible toxicological consequences associated with the formation of antimony oxyhalides or the finally obtained antimony chlorides
and/or bromides during the fires should be further investigated. It is not possible to
draw any conclusions with regard to long-term hazards for survivors of a fire in which antimony based fire retardants were involved. No adequate studies dealing with the toxicity towards the environment elicited by the release of antimony compounds from fire retarded plastics, are available. X. CONCLUSIONS From this literature search it can be concluded that it is unlikely that antimony trioxide causes harmful effects on the aquatic ecosystem. Bioaccumulation in both freshwater and marine species is low to moderate while biomagnification is unlikely to occur. Sb20 3 appears to have a low acute toxicity and the most important route of exposure is inhalation. Based on good laboratory practise Sb20 3 is not genotoxic in vivo and does not pose genotoxic hazard to humans. No conclusive data are available for the effects of human exposure to antimony or its compounds, with the exception of some toxicokinetic data. However, there is limited comparative information on the absorption, distribution and excretion ofdifferent Sb compounds. Only limited data are available relating to carcinogenicity for any form of antimony. What the carcinogenicity of inhaled antimony in animals is concerned, conflicting results were obtained. Tumours were only observed in female rats iflungs were overloaded. For all forms of antimony, data relating to reproductive and development effects are inconclusive or of poor quality. About occupational dermatitis ('antimony spots') following exposure to fumes of antimony metal and antimony oxide, it is not clear if the reaction is due to irritation or sensitisation.
ACKNOWLEDGEMENTS The author would like to thank the following organisations and persons for their invaluable contributions: Prof. Dr. M. Van den Heede from Centre for Environmental Sanitation - University of Ghent, ir. P. Van Sprang and ing. M. Vangheluwe from Ecotoxicity Testing and Consulting, Lic. W. De Coen from Laboratory for Biological Research of Aquatic Pollution - University of Ghent, and the APME for the possibility of using the results obtained in recent studies.
54
01 01
FRCA Code Consultant
ROBERTS.STRENGTH
IMPLICATIONS FOR FLAME RETARDANTS IN THE
DEVELOPMENT OF A SINGLE SOURCE CODE IN
THE U.S.
~
• EXISTING CODES TO BE THE MODELS
• BOCA, ICBO AND SBCC FORM ICC TO WRITE A SINGLE SET OF CODES FOR THE U.S.
DEVELOPMENT OF A SINGLE SOURCE CODE ·
~
• TO SATISFY THE FEDERAL GOVERNMENT'S DESIRE FOR ONE CODE - For International Trade. Home Rule, ie., Keep the Feds out of local regulations
• ELIMINATE DIFFERENCES IN CODE REQUIREMENTS BECAUSE OF LOCAL REGULATIONS
• To SIMPLIFY CODE DEVELOPMENT AND COMPLIANCE
WHY DID THEY FEEL THE NEED FOR A SINGLE
SOURCE OF CODES?
01 CD
• ELEMINATE DIFFERENCES IN CODE REQUIREMENTS BECAUSE OF GEOGRAPHICAL PREFERENCES.
WHY DID THEY FEEL THE NEED FOR A SINGLE SOURCE OF CODES con't
01
CD
• FIRST DRAFT OF IBC PUBLISHED OCTOBER 1997
• PRELIMINARY DRAFT OF BUILDING CODE - OUT SPRING 1997 - HEARINGS AUGUST 1997
• PLUMBING AND MECHANICAL CODES DRAFTED AND PUBLISHED IN 1995 AND 1996
STATUS OF DEVELOPMENT OF SINGLE SOURCE
OF CODES
~
• PROPOSED CHANGES TO FINAL DRAFT DUE IN OCTOBER 1998
• FINAL DRAFT PUBLISHED IN JULY 1998
• HEARINGS ON FIRST DRAFT HELD IN APRIL 1998
• PROPOSED CHANGES TO FIRST DRAFT WERE DUE BY JANUARY 1998
STATUS con't - IBC
......
0)
• CHALLENGES DUE JUNE/JULY 1999 • JOINT MEETING BOCA, ICBO, SBCC (ICC) SEPTEMBER 1999, ST. LOUIS
• HEARINGS ON PROPOSALS TO FINAL DRAFT MARCH 15 - 24,1999 IN COSTA MESA, CALIFORNIA • COMMITTEE RECOMMENDATIONS ON FINAL DRAFT IBC 2000 DUE MAY 1999
• PROPOSED CHANGES TO FINAL DRAFT PUBLISHED IN FEBRUARY 1999
STATUS con't
0) I\)
• PUBLICATIONS FINAL DRAFT AND PROPOSED CHANGES TO FINAL DRAFT ON SAME HEARING SCHEDULE AS IBC
• EARLY 1998 NFPA PULLS OUT OF JOINT EFFORT • FIRST DRAFT OF IFC REVIEWED AT APRIL 1998 HEARINGS
• BOCA, IFCI, SBCC AGREE TO PUBLISH IFC 1996 • ICC AND NFPA AGREE TO DEVELOP SINGLE FIRE PREVENTION CODE 1997
STATUS con't - IFC
~
• DIVORCE OF NFPA1ICC IN FIRE CODE DEVELOPMENT --- NFPA COURTS ANSI
• ADVANCEMENT OF NEW TECHNOLOGY IN BUILDING CONSTRUCTION DESIGN, MATERIALS OF CONSTRUCTION, AND FIRE SAFETY CONCEPTS
• FIRE SAFETY ENGINEERING CONCEPTS EMERGE
• FURTHER DEVELOPMENT OF PERFORMANCE BASED CODES
EVENTS RESULTING FROM DEVELOPMENT OF
SINGLE SOURCE OF CODES IN U.S.
~
• PARTICIPATION ON SUBCOMMITTEES, TASK GROUPS AND WITH ICC STAFF. PATH NOT CLEAR
• CHANGES TO THE CODE DEVELOPMENT PROCESS, VOTING, ETC.
• SIGNIFICANT CHANGES FROM EXISTING TO NEW CODES
• A SINGLE EVALUATION SERVICES SYSTEM?
EVENTS con't
m
• AVOIDING FEDERAL GOVERNMENT
INTERVENTION
Federal government code development restricts open communication between regulator and regulatee
SIMPLIFIED CODE DEVELOPMENT AND COMPLIANCE FR producers must research code areas for opportunities
IMPLICATIONS FOR FLAME RETARDANTS
m
- Cheap imports can be a downside
- Lower FR requirements could result in market loss
• SIMPLIFICATION OF TRADE BARRIERS RESULTS IN INCREASED IMPORTS AND EXPORTS
IMPLICATIONS FOR FLAME RETARDANTS con't
~
- New concepts and products could obsolete existing FR systems
- Fire safe products emerge as viable alternatives in performance based codes
• PERFORMANCE BASED CODES
IMPLICATION FOR FLAME RETARDANTS con't
~
considerations - designers will find other ways to achieve desired fire safety
- If FRs are not fundamental elements in building design
- FR producers need to educate Fire Safety Engineers about advantages ofFR additives
• DEVELOPMENT OF FIRE SAFETY ENGINEERING CONCEPTS
IMPLICATIONS FOR FLAME RETARDANTS con't
co
m
-
-
FR Producers should monitor and influence competing agencies to minimize conjlict and to stabilize the code and regulatory process.
Efforts to minimize these events exist now.
• ICCINFPA SPLIT - Complications result in code and test duplication, conjliction, competition, and compliance.
IMPLICATIONS FOR FLAME RETARDANTS con't
~
• EVALUATION SERVICES - Single application to ICC vs. application to all 3 code groups = Simplification - Downside - If one body rejects application - you lose. Can change to suit descentor and resubmit. - FR Producer's customers and their customers are the applicants. HELPING YOUR CUSTOMERS IN PURSUIT OF ES EVALUATION REPORT IS GOOD FOR YOUR BUSINESS.
IMPLICATIONS FOR FLAME RETARDANTS con't
:1
• CHANGES IN THE NEW CODE FROM THE OLD
- A lot of changes have been and are being made. - Your customers code complying product may no longer comply because of changes made in the development of the IBe or IFC. - Know the status ofyour customers product. - Know the changes to the code. - Challenge code committees action if appropriate by the end ofJune 1999.
IMPLICATIONS FOR FLAME RETARDANTS con't
~
THANK YOU
• IBCIIFC 2000 JUST ANOTHER Y2K EXPECTED RESULT-ARE YOU PREPARED?
Harmonisation of the Testing of European Construction Products: The Final Quarter David L.Buszard FMC Corporation Tenax Road Trafford Park Manchester M 17 1WT
UK. Background The problems posed by the differences in the fire tests used in the various Member States in Europe was highlighted as long ago as 1984 when it was demonstrated that there was no correlation at all between the test methods in the different countries. Correlation was a major problem since there are around 30 different national fire test methods for construction products with an additional 20 more ISO standards. Manufacturers of building products are therefore obliged to carry out many expensive tests if they wish to sell their products throughout Europe. There have been several attempts to solve this problem: • correlation of test methods • ''three sisters approach" based on the German DIN 4102 B2, the French epiradiateur and the UK. spread of flame test • the "robust solution" - heat release/oxygen depletion using large scale and cone calorimeters Finally in 1993 the Group of National Fire Regulators was formed and the concept of Euroclasses was born. This resulted from the identification of the common key features of fire control which were believed to be important to each of the Member States. A series of six classes of fire performance was identified and the performance of each was set. After much deliberation two series of test requirements were derived; one for flooring and the other for wall and ceiling products. Six test methods were identified as being necessary to measure the reaction to fire performance. Five of these methods were standard tests (ISO bomb calorimeter, ISO small furnace, the small flame test, the radiant panel test and the methanine pill test. This latter test has recently been dropped. No suitable candidate could be found for the sixth test which was needed to represent the thermal attack of a burning waste paper basket or a small item of furniture. Consequently the concept of the "Single Burning Item" or SBI test was formulated and a work programme agreed in May 1995. The basic concept ofthis new initiative was to produce a set of harmonised test methods by consensus and not to further the development of fire science or safety. Moreover it was the intention that this initiative should not upset the 'status quo' of the existing use of traditional construction materials.
73
The responsibility for the development of the SBI test was given to the Official Laboratories Group, (OLG). It has required considerable effort to develop it to the point where it could be used as the basis for regulatory classification. The programme is now nearing the end.
The SDI Test The design of the SBI test and the construction and testing of prototypes was completed by mid 1997. It is basically a corner situation which is mounted in a test rig with a high air flow. This was followed by a 'round robin' involving 20 laboratories and 30 building products. The plastics industry was surprised by the decision to include a number of 'linear products' in the round robin such as cable pipes and conduit. However the testing of these products raised issues of mounting, relevance of testing scenario and reproducibility for these products and so work on these types ofproducts has been shelved for the time being. The round robin was completed in just 11 weeks. Many problems were identified and quite a few were solved 'on the run' as development and testing proceeded. The test method in its final form has therefore only been around for about one year and manufacturers are only just now building up experience on the performance of their products. Having developed the test method the next problem was what to measure and how to classify products and performance. The Scandinavian Laboratories who had extensive experience in developing the ISO room-corner test were instrumental in devising the FIGRA (Eire Qrowth Rate) index using oxygen depletion as the basis for measuring heat release. The other parameters are recorded and now only considered as a 'safety net' for products showing exceptional behaviour. Smoke and burning droplet classifications are independent of the fire behaviour classification and the subject of additional declarations on the test certificate. The favoured means of assessing the smoke is by SMOGRA (SMQke Qrowth RAte) The SBI test was validated by reference to the Room Corner test and a good correlation seems to have been achieved through FIGRA. However plastics manufacturers in Europe are concerned by the data available which suggests the SMOGRA index is less satisfactory since it shows reverses in performance between wood and typical plastics material between the room corner and the SBI test.
Current Situation The responsibility for the development of the SBI test has now been passed to the European Standards Committee responsible for the fire performance of construction products, CEN TC127. They have already been working on developing the Euronorms or Standards (ENs) for the other five reaction to fire tests as well as fire resistance. The SBI test is therefore essentially complete apart from some minor modifications/improvements. However there is still ongoing debate on the exact classification criteria for the various classes. Besides the scientific debate there is also a number of 'political debates' occurring. These are typified by the debate as to whether the highest classes should be Al and A2 or whether they should be combined into a single A class with a 'superclass' for non-combustible materials which should be outside the classification table. These debates
74
are as a result of considerable lobbying by the manufacturers of various classes of building products. It is expected that this debate will be finalised at the next Regulators Group and Standing Committee meetings in March. There has also been much debate and lobbying around the classification of floor coverings which is likely to result in last minute changes to the performance requirements in the classification table. Along side the work currently being done by CEN TC127 other CEN TCs are meeting for each of the different product groups to develop performance standards covering all other aspects ofperformance. These standards will utilise the CEN TC127 standards for fire performance and will form the basis for the Euroclassification system. This will enable building products to be marked with the CE symbol together with a fire performance classification which will include the additional declarations relating to smoke and flaming droplets where appropriate.
The Next Steps The plan is to have the standardisation process and the Euroclassification in place by 2000. This is still an ambitious timescale but pace has gathered from the slow start and it may well be possible for the majority of 'easy' building products. This is the end-point the European Commission has been focusing on for the last five years. However it is not the end of the process by any means - Europe will have a harmonised series of test methods and a classification system BUT there will be no harmonisation ofthe building codes in the different Member States. These will remain the responsibility ofthe individual countries. There are therefore two further important steps which have to take place before this round of harmonisation is achieved: 1. Member States have to decide how to replace their current national test classifications in their current building codes by the new tests and classification system. 2. There will have to be a well arranged transition period between the current system and the new classification. !) will take place in each ofthe individual States and will no doubt involve much lobbying by local manufacturers to ensure their products are not disadvantaged by the new test classifications. 2) is almost certainly going to be decided by the Standing Committee within the European Commission - periods ranging from 6 months to five years or even 10 years in the case of fire resistance are being considered.
Conclusions
75
The final shape of the harmonised European classification of fire performance of building products is still not agreed. Building product manufacturers are hurriedly trying to come to tenns with the new classifications for their products but it is likely to be several years before the whole system stabilises. In the meantime Flame Retardant manufacturers need to be aware of the developments and vigilant in looking for the new opportunities which
may arise as products are modified to meet the new classifications.
76
Paper for FRCA '99 Conference Th. Uhlenbroich Zinc-sulfide-based flame-retardant systems Abstract The fact that zinc sulfide is capable of achieving a significant flame-retardant effect in a most diverse range of polymer systems has been know for many years. It is possible in many systems to replace antimony trioxide partially, or even
completely. The zinc sulfide used as a flame retardant up to now, however,
possessed optimized white-pigment properties and not optimized flame-retardation
. properties. Zinc sulfide has now been optimized for use as a flame retardant, both alone and in combination with organic and inorganic synergistic components. In addition, an attempt has been made to clarify zinc sulfide's mechanism of action. One system in which complete replacement of antimony trioxide with zinc sulfide is possible is, for example, rigid PVC. The mechanism of action of zinc sulfide in flame retardation has been explained in more detail using model substances based on rigid PVC with and without the incorporation of zinc sulfide. Although it has not yet been possible to completely explain the precise mechanism, clear indications were obtained that the flame retardant action of ZnS can largely be attributed to the formation of a non-combustible layer of carbon (char). This formation of char results in a significantly lower supply of combustible gases for the flame and for the continued combustion of the plastic, and thus in extinguishment of the flame. A further advantage can be found in the fact that the generation of undesirable combustion gases and combustion-gas particles is drastically reduced. In addition to these directly demonstrable and beneficial flame-retardant actions, zinc sulfide also has other properties which significantly improve the plastic system. Particularly worthy of mention in this context are improved thermal stability, resistance to ageing, pigmentation properties, improved processing characteristics, dry lubrication properties, and several others. The conclusion drawn from the totality of all these properties is the fact that the zinc sulfide-based flame-retardant systems presented here may well be the ideal flame retardants for a large range of polymer systems.
n
Experiments
An attempt is made below to illustrate in more detail the flame-retardant mechanism of zinc sulfide. The lOI test and a test analogous to that specified in Ul-94 were used for determination of f1ame-retardation properties. The following rigid-PVC-based model substances were prepared and examined for their f1ame-retardation performance: 1) 2) 3) 4)
Rigid PVC Rigid PVC + 10 % Sbz.03 Rigid PVC + 10 % Zn~ Rigid PVC + 5 % Sb20 3 + 5 % ZnS
These mixtures were prepared without any other additions in a Ca/Zn-stabilized rigid PVC mixture on a laboratory roller-mixer (manufacturer: Schwabenthan) at a temperature of 1650 C and a rolling time of five minutes. The rolled sheets were then compressed for a compression time of seven minutes (4 min. without pressure and 3 min. at 300 bar) at a temperature of 1700 C to form tiles of 3 mm thickness. Test sticks for performance of the lOI (limiting Oxygen Index) test and for classification in accordance with Ul-94 V were sawed from these tiles. The Sb20 3 and Zns concentrations were deliberately selected slightly above the strictly necessary concentrations, in order to permit better analysis of the effects occurring. Thermal, mechanical and other analytical methods were used in addition to flame retardation indices in order to characterize the model systems. Results and discussion
The f1ame-retardation indices (lOI) for the model substances examined are shown in Figure 1. It is apparent that zinc sulfide produces a significant increase in the lOI value compared both to pure PVC and also to PVC extended with antimony oxide. The best flame retardation indices are obtained with a combination of zinc sulfide and antimony trioxide. Thermal-analytical tests (TGIDTA) were performed on all the model substances. Dehydrochlorination of the PVC starts at around 240 0 C (Figure 2). In the presence of antimony trioxide, the starting temperature for dehydrochlorination remains constant, but a fine structure, which is probably associated with the formation of antimony oxychlorides up to and including antimony trichloride, occurs in the temperature range around 500 0 C (see Figure 3). The model substance containinQ 10 % ZnS exhibits a starting point for dehydrochlorination which is shifted Significantly toward lower temperatures (Figure 4). Unlike the case with PVC and PVC containing antimony trioxide, however, this dehydrochlorination process remains incomplete.
78
In the case of the combination of ZnS and Sb20 3 , dehydrochlorination is dominated by ZnS. The fine structure in the OTA signal, on the other hand, can be attributed to the antimony trioxide (Figure 5). In addition, pyrolysis tests were performed at various temperatures (see Figure 6) on the model substances. In this case, it became apparent that the pyrolysis residue is reduced in the case of PVC when antimony trioxide is present. Zinc sulfide, on the other hand, causes a significant increase in pyrolysis residue. The combination of S~03 and ZnS is also dominated in terms of pyrolysis residue by ZnS. Further pyrolysis tests were performed at 670 0 C using the test apparatus shown in Figure 7. Quantitative evaluation of the pyrolysis residue is shown in Figure 8. The residues of the rigid PVC specimen and the specimen containing Sb20 amount to around 5 % and are identical within the limits of measuring accuracy. Tfiis means that antimony trioxide has no significant influence on the amount of remaining carbonization residue at the pyrolysis temperature selected. As indicated in the relevant literature, antimony trioxide's manner of action can be found virtually completely in the gas phase. The rigid PVC specimen containing zinc sulfide, on the other hand, produced an approximately threefold greater amount of pyrolysis residue. A carbonization residue of still no less than approx. 2.5 times the amount compared to rigid PVC alone is also found in the case of the combination of zinc sulfide and antimony trioxide. This also explain the synergistic effect in the combination of antimony trioxide and zinc sulfide, i.e., a gas-phase mechanism combined with the formation of a protective layer. One disadvantage of antimony trioxide can be clearly found in the increased production of combustion gas (see Figure 9). Compared to pure rigid PVC, the rigid PVC specimen containing antimony trioxide emits an amount of combustion-gas particles around three times greater, despite the fact that the amount of pyrolysis residue is approximately the same. In the presence of zinc sulfide, the amount of combustion-gas particles is reduced by around two thirds compared to PVC containing Sb20 3: The gas phase was also analyzed by means of pyrolysis/gas chromatography/mass spectrometry (see Figure 10). The main substances found, in addition to hydrogen chloride (not shown here), were benzene, methyl benzene and naphthalene. It is clearly apparent that the amount of combustible gases generated in the presence of zinc sulfide is greatly reduced.
Non-PVC polymers In non-PVC polymers (containing 10 % decabromide diphenyl ether, however), the antimony trioxide content required in standard formulations was partially and completely replaced with zinc sulfide. The corresponding formulations were submitted to the LOI test and (analogously) to the UL-94 test.
79
The corresponding test results are shown in Figure 11 . It is apparent that 50 % replacement of antimony trioxide is possible in virtually all polymer syste(Tls.
Polyamide Excellent flame retardation can be achieved in polyamide and glass-fibber-reinforced PA with a suitable combination of zinc sulfide and melamine cyanurate, i.e., with no halogens and no antimony trioxide. The LOI results for corresponding synergistic combinations (Flameblock FB) are shown in Figure 12. It is apparent that LOI figures of up to 40 % O2 can be achieved for polyamide with a suitable combination. It is possible to achieve classification analogous to UL-94 VO for polyamide and classification to UL-94 V2 in the case of PA-GF.
Thermal stability and mechanical properties In addition to the above-mentioned beneficial effects of the use of zinc-sulfide containing flame-retardation additives on the flame-retardation properties of a large range of polymer systems, there are also benefits in terms of thermal stability, resistance to ageing and mechanical properties. The thermal stability of rigid PVC containing various zinc compounds is shown in Figure 13. It is apparent that the system's thermal stability is improved significantly only in combination with zinc sulfide.
Conclusions It was possible to confirm the gas-phase mechanism of action of antimony trioxide. Zinc sulfide, on the other hand, acts largely in the condensed phase. Zinc sulfide promotes the formation of a non-combustible protective layer (char). The escape of combustible gases is minimized by this protective layer. In particular, combustlon-gas density is drastically reduced compared to antimony-trioxide-containing PVC. In polyamides, excellent flame retardation can be achieved without halogens and without antimony trioxide. In addition to their flame-retardation properties, zinc-sulfide-containing flame retardation additives also have a beneficial influence on thermal stability, resistance to ageing and the mechanical performance of the various polymer systems.
80
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11 550°C
I
• .1
°specimen
- ---1
1-1
50
60
70
80 1- - -
1
1[. 350°C 40
300°C
c.J
a
~ 90
~:§
~100
---...
10% ZnS
10% Si>203
--------=~----=_
5% Sa ZnSI 5% Si>20 3
Calcining Iou at various calcining temperatures (Calcining time 2h in each ca. .)
Zinc suHide as a flame retardant
~
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20%
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1
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,~- I
PVC + 10% Sb203
PVC + lO%ZnS
PVC + 5% Sb + 10% Zns
Combustion gas partlcl•• In %
Zinc sulfide as a flame retardant
i* ~
....
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SACHTLEIEN
~
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0
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IIIIO%ZnS
__ lO%Sb
Rigid PVC
5
10
15
20
25
30
Benzene
Methylbenzene
Zinc suHide as a flame retardant
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ASTM 02671
cable
Category C
(3)Corrosion test
burn to top of the
part 2 : Bunched wire and cable 1. 5 1/ain,20ain flue application
cable test , not
cable
test pass
IEEE 383
(ASTM 662NF)
part 1 : Single vertical insulated I Vertical group
IEC332
TLI. 70>
(IEC-I034)
6)Saoke eaission
2863)
Om 400>
2)Saoke eaission
350.g)
I)HCL gases
apply to sheath
Vertical group cable
LOGA test pass
~
5)Teaperature Index Test(ASTM D-
4)0. I (ASTM,D-2863) ain 27
3)Jeighted Conductivity 10
2)PH Values 4. 3
o.l part
Al(OH)s
Red phosphorous
l)Carbonic acid
Mg(OH)%
D-2Owt%
2)Acid anhydrite
lOOwt%
JP-179675(1995)
3)Epoxy group
4) Hydroxyl ~up
Ethylene- a olefin copolymers
Surface treated
Fatty acid metal
Mg(OH)2
salts(8-2Ocarbon)
D-2Owt%
Zinc Stannate
JP-90134(1995)
Mg stearate O.6-3wt% Polyolefine
Al(OH)s
Zinc Borate
Mg(OH)2
1-5Owt%
5D-20Owt%
siloxan modified
JP-41611 (1995)
acryl polymer O.l-lOwt% Polyolefine
EVA or polyolefine
Al(OH)s
Silicone oligomer
Mg(OH)2
O.5-2Owt%
Al(OH)s
Heat expansionable
Mg(OH)2
graphite and red
JP-304891(1995)
JP-I 13662(1996)
phosphorous 5-lOOwt% Polyolefine
Mg(OH)2
Ni compound
JP-50810(1996)
50-30Owt% EVA
Al(OH)s
APP 5-10Owt%
JP-48870(1997)
Zinc compound
JP-3659 1(1998)
Mg(OH)2 EP copolymer
Mg(OH)2
lOD-25Opart Mineral process oil 20-5Opart
106
In spite of this situation we already developed the nonhalogen flame retardant materials and applied to commercial products. Table-2 shows the flame retardant level of practical nonhalogen materials for wire and cables. In these few years the basic study of metal hydroxide , the effect of assistant agent to improve the flame retardant efficiency of metal hydroxide, and the char stability during combustion have been studied to reduce the volume of metal hydroxide. Some example of Japanese patent about effect of assistant agent and polymer polarity controls will be shown in Table 3. We studied the flame retardant effect of four kind of metal hydroxide, the effect of assistant agent and surface treatment of metal hydroxide. We would like to present next three subjects. (l)four kind of metal hydroxides .a.;, Al(OH)s, lL. Mg(OH)2,~: oxalic acid modified Al(OH)s is m- Al(OH)s ~ Ni compound coated Mg(OH)2 is m-Mg(OH)2 (2)assistant agent ofm-Mg(OH)2 (3)the effect of surface treatment .a.;, normal aliphatic surface structure surface treatment b.: branched structure aliphatic surface treatment
2.Experimetal 2-1 Tested Samples 1) Base polymer ethylene-propylene copolymer 2) Flame retardant additives (15Ophr) Al(OH)s , Mg(OH)2, m-Mg(OH)2 ,m-Al(OH)s 3) Flame retardant assistant agent for metal hydroxide(5phr), m-Mg(OH)2(120phr) , Silicon polymer powder, zinc stannate , carbon black ,phosphoric ester 4)Surface treatment surface treated Mg(OH)2(150phr) Branched alkyl aliphatic acid ,normal alkyl aliphatic acid ,no additive
107
2-2 Experimental Method
Experimental method were shown as Table 4.
T able 4 E.ixpenmental Mthd e 0
characteristic standard No. of test Tensile Strength(TB) JIS K6301 I)Mechanical properties Elongation (EB) 2)Heat aging properties Retention of TB JIS K6301 121'C X 168hr Retention of EB p(Q-cm) 3)Electrical properties JIS K 6911 tan ~ 4)Oxygen Index JIS K 7201 HRR 5)Combustion behavior by ASTME 1354 TotalHRR cone calorimeter Smoke emission CO,C02 emission Combustion residue Thermal analysis by DTA,DSC 3. Experimental Results and Discussion Experimental results were shown in Fig.l....Fig.9 and Table 5....Table 7. Table 5: Electric, Mechanical properties and Flame Retardant properties (1) (Z) (3) (4) Items
unit
te.t of . t a n No.
Bootriool_rli..
p
tan 6
A.......rdont
01
_rtleo
TotoItflR TotoI""ol. .nioaion A....... oni_onofCO A....... oni_onofCO.
Re.....
Ma 3000c • Heat Sink: Endothermlc decomposition to M and CA • Inert Gas Source: CM): Dilution of oxygen and fuel gases • Non-burning dripping (CA): Decrease of exposure to flame
13 L] tnelapu~C
Compound Properties • Halogenfree • Low smoke density • Low 10000ing levels
• Excellent electrical properties • Colorabllity • High effttctivity 14 0
Flame Retardancy and Processing • Degree of dispersion • Temperature control problems
• Kneading Capacity
Inconsistent Processing
FR
Inconsistent
FRand
processing
problems
1~
I:l ma6tpur-MC
126
Compound properties in PA • PA 6.66 unrelnforced: Ul94 V-Q at 6 -10 wt.% • PA 6. 66 mineralfilled: UL 94 V-o at 13 - 15 wt.% • PA 6, 66 glassrelnforced: UL 94 V-2. Glow wire 960 OC, CTI > 500 Volt 115 ~
NIP Systems for PBT UF/GF FR - Mechanism Intumescent Systems • P - caused degradation • Char forming - role of additives • Blowing agents • Gas banier
17 c::J mBl.pu~C
& P-synergist Compound properties in PBT • PBTunreinforced: UL 94 V..o: 5-15 % MC. 50 10 %Phosphatee
• PBTglassreinforced: UL 94 V-2, Glow wire 960 DC. 10-15 % MC, 5 - 10% Phosphonates
• PBTglassreinforced: UL 94 V-O: Under development
18 c:J mslapu'-200
FR - Mechanism in PA 66
19 c:J
Intumescent Systems • P - caused degradation • Char forming - role of polyamide • Blowing agents • Insulation and gas barrier mfllaptl,.200
Material Properties • High thermal stability TGA isotherm 3000C TGA Isatt(-rm 3250C
(weIght 101& ,.):
0.20 - 0.40 0.40 - 0.70
• Very low solubility in water: < 0.01g/100m1
• NIP ratio
approx. 4/1
127
20 [al melapunOO 21 ~
22
0
Thennal Stability - TGA mlllllpunoo
Pa rtlcle size
melllPu'-200 Compound sta~s PA 66
Formulation: 25GF, 25FR. 50 PAB6
UL. ~ , ,8mm
V~
2.1 - 2.3
11.2
[Mpa) 160 Elongation at break Charpy unnotched [kJIm2] 48
eT! Glow WIre
23
[Gpa]
E-modulu8 TenaMe s1rength
M
350
re)
960
Cl trIfI/IIpu~200
Compounding conditions Extruder: ZSK 30.33 W+P. twin screw, synchronous Screw apeed 100 • 150 Rpm Output 10 -12 kglh (torque 85%) - 0,8 bar Vacuum: PA66: < 0.10 wt.% H20
24
0
25 ~
26
0
mel.pu,.200 Compounding conditions Corrosion Patent situation. DSM
Status
Type
Applied
Patent of MBtter. Mela"*l8 PoIyphoaphate
Application in PA, GF In PETGF
Granted
Apptied
21 l:) Patent situation, Overview
128
(%]
FRCA - March 1999 New Developments with Phosphorus-Based Flame Retardants for Engineering Plastics, Polypropylene, and Thermoset Resins AUTHORS: Sebastion Hoerold, Wolfgang Wanzke (both of Clariant GmbH), and *Dan Scharf (Clariant USA) - Speaker ABSTRACT: In recent years Phosphorus-containing compounds have seen use as flame retardants (FR's) in plastic applications. Developments are continuing to expand this technology for broader polymer coverage. This paper will present some new phosphorus-based product developments that have promising commercial potential for ETP's, polypropylene, and thermosetting resins. ETP's: A new class of organo-phosphorus derivatives have been found effective as a tool for flame retardancy in several engineering resins. Combinations with synergistic compounds result in tailor made formulations that work best in ABS, thermoplastic polyesters (PBT/PET) and polyamides. Polypropylene: Intumescent FR's for polypropylene have been improved as well and offer new opportunities for FR PP to compete with ETP's. Examples will be shown of electrical and building applications under demanding conditions. Thermoset Resins: Ammonium polyphosphate and red phosphorus when combined with aluminum trihydrate in thermoset resins exhibit new options in transport applications. These synergistic combinations yield materials of lower density and reduced viscosity for easier processing. The resulting polyester and epoxy resins have outstanding FR properties with low smoke and corrosive off-gas behavior.
129
_ ...
_IIU
~. Clariant
21 .10._. _
Phosphorus-Containing Flame Retardants organic
inorganic
O-o,j!.J)
TPP
6
RP
(!riQhenyl Qhosphate,
(Bed Qhosphorus)
NHi+ NH~+ NH:
--o-~- o-~- o-~=o-d
RDP
8
n
6
APP
(Be.orcinol-tetraphenyl JfiQhosphate)
(Ammonium QoIwhosphate)
Chart 1
I. Introduction Phosphorus-containing substances, especially phosphates, have been used for some time as flame retardants, e.g. in textiles and coatings, and are employed increasingly in plastics. Chart 1 shows some industrial phosphorus products that have been used by the plastics industry for many years. A rough distinction can be made between purely organically and inorganically substituted phosphorus compounds, depending on their chemical structure. The property profiles differ correspondingly during the plastics processing, from filler type (in RP and APP) through to plasticizing (in TPP and RDP). This paper covers new developments in phosphorus products that are significant above all in the engineering polymers sector, i.e. design materials. Here there are two attractive paths toward solving problems. First, the search for completely new active ingredients and second, the formulation of customized flame retardants based on established materials. Both paths have been successfully followed, as the following examples show.
130
--ou_
~.
10.10.'1.0. W.
'.
~' Clariant
New Active Ingredient Class: Organophosphinates
• Chemical basis for effective flame retardation of engineering polymers without halogen-containing substances
• efficient synthesis
• synergistic formulations for ABS. PA. PBT. PET
• -customizing- of individual plastics Ch..t2
11. Organo-Phosphorus compounds as a new alternative Let us take a look at a new active ingredient class that was synthesized some years ago in the laboratory and whose good flame retardaney properties were noticed at the time. Efficient syntheses have now been worked out for production and special formulations have been developed so that these new organophophorus flame retardants will soon be market-tested. These are salts of organophosphinic acids. The generic structure is shown in schematic form above (Chart 2). These salts form an interesting new basis for the halogen-free flame retardancy of engineering polymers. A whole range of synergies has been found with other FR components which permits the development of customized formulations for various engineering polymers, e.g. ADS, polyamide and polyester.
131
. --
~.
~' Clariant
10.'0.. . .. . . .
Organophosphinates: Properties
• white powders • non-fusible during processing • non-hygroscopic • non-toxic. not requiring special labeling
Ch.n3
The new organophosphinate compounds are white, finely crystalline solids that do not melt during plastics processing (Chart 3). They therefore have a filler character and correspondingly change the property profile of the polymer. However, until now there have been no halogen-free name retardants that are as efTective in terms of % load factor in ADS or polyesten, and so the filler character has much less of an effect than e.g. metal hydroxides, relative to the same name retardaney standards, such as UL 94 V-O. The phosphinates have so far proved to be non-toxic and have been classified as "non-mandatory labeling." As they are new substances under the Eu and TSCA directives, registration is necessary. Part of this process has already been carried out.
132
--
~.
ao.1a.8!1iDr.w.
~ ' Clariant ®
28
Exolit OP 11 00 (TP) - Flame Retardation in ABS
.... ........................................... .. ... ....... ... ....................... .. ..... ....... ....... .
26
...... ............. ............. ... ....... .. ......... ... ........... ..... .
22
..........••........•...••...•...•.....•........•.......•.........
20
.. ......... ......................... .......... .. ....... .. ......... ...... ... ............... ... ... .. ... ... . .
18+------.-------r------,-------r-----~------~
o
5
10
15
20
Exolit OP 1100 (TP) [-AI by weig~l
25
30
Cbart4
Chart 4 above shows an example of the effectiveness of such formulations. In a commercially available ADS blend, the LOI rises in an almost linear manner upon addition of the new test product ~Iolit OP 1100 and achieves, with 30% flame retardant content, a value of 28.5. For use in electrical engineering however, classification to UL 94 is much more significant. The frequently specified v-o class is achieved with 25% EIolit OP 1100 (TP). Historically, this was not possible with other halogen-free flame retardants. The V-2 class is reliably obtained above 10% addition, although the minimum quantity for this classification has not yet been determined. EIolit OP 1100 (TP) is a formulation based on an organophosphinate, as shown on page 2. This product additionally includes synergistic, nitrogen-containing components that permit a UL 94 V-O classification. In fact, out of hundreds of formulations only a few proved to be effective enough to achieve a V-O in ADS @ 25 wt % loading. In addition to flame retardancy, other criteria to be met include mechanical and electrical properties as well as aging resistance. In addition, special effects can be achieved with the new formulations, e.g. UV stability.
133
--
.~ . :::::,; , ClaTiant
11 .'0....,... .,...
®Exolit OP 1100 (TP) - Light Stability 120 ..... .. ... ................. ... .......................................... ........... ...... .... .. ............ ............. .. 100 Surf_ embrlttlement
= I
aft.85OOh
I
80
~
40 i ..........~-...-~ ········ · · · ·······
• •om.whet ., .om.whet • mongly
80 ~ ABS
*
nIItLnI + 25" Exolt OP 1100 (TP)
-.-wIIh 20 .................... ................................ '--_ _bromi1e2500
2000
1000
....... .... .... ............ 800 · .. ····················································•
500 60 ®ExolltAP 750
ChIor. Cyclo..,hdc
Brom. Phlhalimide
Chart 12
Obstacles relating to high-quality light stabilization have already been discussed. Halogen-containing flame retardants impair in particular the function of sterically hindered amines (HALS), as a result of which the production of long-life articles for external use with halogen-containing flame retardants is only possible to a limited extent. As with the organophosphinates, intumescent systems are non-interactive with light stabilizers of the HALS type. FR-PP based on an intumescent system in combination with a HALS produces a significantly higher resistance to discoloration and surface embrittlement compared to a HALS stabilized FR-PP based on a halogen FR. Chart 12 illustrates (FR formulations containing 0.3 wt % HALS - Hostavin® N20).
142
_ ...
AJAditI...
)O.10.MIDr . . . .
Water Immersion (100 Days) o
20
eo
80
100 Oeys
-1
j ~ -1.5
~ -2.5
.....................................................................................................................
11 llExolit AP 750
o FR3
pp copolymer with 30% fleme r.terdent (UL 94 V-OI
Cbart 13
For external applications, the question of water resistance of the flame retardant in the pp compound is relevant. In water immersion tests the long-term effect of rainwater on the material can be simulated over a reduced period of time. Chart 13 shows a comparison of two formulations in pp over 100 days. The weight loss of the two materials over time is relatively similar and after 100 days amounts to approx. 2%. If the flame resistance of the samples are considered over specific periods of time, then it becomes evident that in the case of the FR 3 system (ref.4) the V-O classification is lost after 20 days, while with the same quantity of ®Exolit AP 750 the V-O still applies even after 100 days. Since the intumescent flame retardants are generally multi-component systems, there is a risk that a component with higher solubility is selectively dissolved and thus the synergy is lost. Overall, intumescent flame retardants based on ammonium polyphosphate are good examples of problem solvers for PP. Through new formulations, these products can frequently be adapted to the needs of various applications.
143
-.
.
~. ~··Clanant
Flame Retardants for Thermosets - Requirements • Ughtweight high-performance plastics are increasingly used in the transport sector • Thermosets (UP. EP. phenolic and polyurethane resins' play an important part here • Until now. flame retardants. smoke requirements. weight and procassability could not be harmonized
New flame retardant combinations based on phosphorus are the solution Chart 14
IV. Flame retardants for thermoset resins Depending on the area of application, different demands in terms of mechanical, electrical and fire-protection properties are placed on thermoset resins (Chart 14). Especially in the area of rail vehicles, the fire protection requirements have recently been tightened. Halogenated UP resins can be used to make glass fibre reinforced compo nents. These are produced in such a way that during condensation bromine or chlorine-containing carboxylic acids and/or alcohol components are used. Examples include hexachloroendomethylene tetrahydrophthalic acid (HET acid), tetra-bromophthalic acid or dibromoneopentyl glycol. As a synergist, antimony trioxide is frequently used. The disadvantage of bromine and chlorine-containing resins is that in a fire corrosive gases are given off that can cause considerable damage to electronic components, e.g. relays in rail vehicles. Under unfavorable conditions polychlorinated and brominated dibenzodioxins and furans can result.
144
-...-
~ ~ ·· Clariant
Flame Retardants for Thermosets - Fire Tests Application
Test
Description
Classifications
Construction
DIN ..102
Chimney test
81>82
NFP 92-501
Eplradlateur
M1>M2>M3
8S ..76
Flame propagation
1>2>3
DIN 5510
Afterbum time and smoke density
NFF 16-101
Eplradlateur + smoke
SbS3 SR1 &SR2 ST1 &ST2 M & F-class
UL9..
Afterbum times
V-4>V-1>V-2
Transport
Electrical Industry
Cbartl~
Aluminum hydroxide can be used to impart flame retardant properties to UP resins. The effect of the aluminum hydroxide is based mainly on water separation at elevated temperatures. To attain high flame retardant requirements (Chart 15), very highly filled grades (up to 400 parts 1100 parts UP resin) are necessary. The resulting rise in viscosity of the UP resin blend can at least be pardy compensated for by using viscosity reducers. UP resin laminates are processed in different ways. Components are produced in large numbers by the SMC (sheet molding compound) process. Here high filling levels are possible, so that even with aluminum hydroxide high flame retardant requirements can be met. The high specific weight is a disadvantage with such systems. Attempts are made to reduce it e.g. by adding hollow glass beads. High filling levels are also possible with the BMC (bulk molding compound) process. In hand I.y up and resin transfer molding (RTM) however, the filler proportion is limited for process reasons. High name retardant requirements have so far been achieved only with halogenated UP resins, sometimes with the addition of aluminum hydroxide.
145
.. -
Flame Retardants for Thermosets
- Unsaturated Polyester Resins, Transport Sector Synergies with Ammonium Polyphosphate and Red Phoshorus Fonnul.tio.,. for Bundaeb.hn ohlmnay teat DIN &&10.201... S4 SR2 8T2 FR oontent [phr) 200
• Exolh RP 664 [] Exolh AP 422
150
-ATH
100
- low filler oontent
50
o
- 30% Iow.r denelty (oa. 1.S glom'"' 1
2
3
Chartt6
By using ~xolit ammonium polyphosphate and red phosphorus products
in combination with aluminum hydroxide, formulations can be developed that meet halogen-free requirements, the highest flame retardant demands, and at the same time, because of the low filler proportion, are suitable for hand lay-up and RTM. The UP resin blends are characterized by low viscosity and can be both hot- and cold-cured (with cobalt .cceleraton). Where UP resin laminates are used in rail vehides for passenger transport, fire protection requirements must comply with DIN 5510. Depending on use of the components, fire dasses S3 or S4 can be met, and also the smoke development dass SRl can be attained. Chart 16 shows FR loading requirements of Exolit products (refs. 5/6) in combination with ATH compared with pure ATB in fire tests according to DIN 5510.
146
. --
~ ..
Flame rRetardancy for Thermosets
- Unsaturated Polyester Resins, Transport Sector -
Processsbility Fonnul.tione for Bundeabehn chimney teat DIN 5510,201••• S4 SR2 ST2
Dynamlo vlaooelty (Brookf".Id, 25°C, 100 rpm, 0.85% Byk W 985)
• Exolit RP Cl Exollt AP .ATH
- aIgn.....tly low. vfaooalty
of the formulation 2
3
Chartt7
By combining ATB with phosphorus-containing flame retardants the processing viscosity of the resin blends can be considerably reduced (Chart 17). This is an important factor particularly in hand lay-up and injection processes. Moreover, components with high glass content (30 50%) can also be made flame retardant.
147
-..-
~ ' Clariant
Flame Retardancy for Thermosets
- Unsaturated Polyester Resins, Transport Sector
Smoke Properties Measurement of the smoke development NBS Smoke Chamber I ASTM E-662, flaming conditions Smok. deneity 0.
800r-----------------------------,
500 400
- low emok. deneity
300
- Import....t for:
ra •• aircraft, ...Ipe
200
- ABO and FAR fulfilled
1
2
3
4
6
TIm. (mini
8
Cbar118
Where glass fibre reinforced components are used in public transport vehicles the smoke density of the materials is of great importance, because smoke reduces visibility and can thus considerably lengthen escape times. Chart 18 shows the optical smoke density of UP resin laminates (30~. glass) with halogen-containing and halogen-free ~xolit AP 422 + ATB) name retardants (test requirement: NBS Smoke Box). When Exolit AP 422 (ammonium polyphosphate) is combined with aluminum trihydrate the optical smoke density in the early phases of the fire is very low.
148
.. --
~' ~" Clariant
Flame Retardancy for Thermosets
- Unsaturated Polyester Resins. Transport Sector Smoke Properties Measurement of the smoke toxicity to ABO 0031
NBS Smoke Chamber 4 min. flaming conditions
Concentration [ppm) 1.500
B halogenated ruin • bollt AP 422/ATH
- no corrosive smoke
co
NOx
HCI
Cbart19
Chart 19 shows a smoke analysis of UP resin laminates (30% glass) after 4-min. combustion, flame retarded with ~xolit AP 422 + ATB (test requirement: ASTM E-662INBS Smoke Box). The materials that are flame retarded with Exolit AP 422 and aluminum trihydrate do not give off any corrosive hydrogen halides and produce only traces of nitrous oxides fumes (NOx). The limits demanded by Airbus Industrie are easily complied with.
149
-. -
~·Clariant
Flame Retardancy for Thermosets
- Unsaturated Polyester Resins, Construction Sector Flame retardancy properties under various test conditions Formulations according to Epiradiateur Test NF-P 92-501 Class M2 @ 3.0 mm (118·' FR content [phr] 250
- Exolit RP Exolit AP
Cl
200
-ATH
150 100 50
o --.
1
2
3
Red Phosphorus is Much More Effective in the Epiradiateur Test than APP Chart 20
For rail vehicles different national regulations currently apply, but these are reciprocally accepted in some cases. Where UP resin laminates are used in passenger rail vehicles in Germany the fire protection requirements according to DIN 5510, Part 2 have to be satisfied. Small parts are tested with the pilot light test according to DIN 53438 Parts 1-3. Sheet, components and coatings are checked according to DIN 54837 with a gas burner with a slot nozzle ("Bundesbahn chimney test"). Depending on use of the components, the fire classes S3 or S4 have to be satisfied, and in most cases the smoke development class SRl also has to be complied with. For floor coverings the "Radiant Panel Test" procedure (DIN 4102 Part 14) is relevant and for seats the paper cushion test based on mc 564-2 is used. In France, the requirements according to NF F 16-101 apply to rail vehicles. The class division MO to M4 is carried out in line with the French tests for the construction industry based on NF P 92-501 (Chart 20). The test includes ignition, flame propagation and dripping behavior. For smoke development and toxicity the F classes FO to F5 apply on the basis of the tests NF X 70-100 and NF X 10-702. The French tests have been taken over by Belgium, Portugal and Spain.
150
.. -.. --
~'ClaTiant
~
Flame Retardancy for Thermosets - Epoxy Resins Effect of Phosphorus Compounds
260
FR content' phr • Exolit OP 910 116
UL 94 V-O 0 1'16"
200
• Exolit RP 650 113 rJ Exolit AP 422 115
• ATH
160
111
- Iowe, filler content
100 60
- high g.... oontent poeelble
0 2
3
4
6
11
- low vieooeity
Chart 11
Phosphorus compounds are very effective flame retardants for epoxy resins. The solid flame retardants ~xoHt AP 422 (ammonium polyphosphate) and Exolit RP 650 (based on red phosphorus) can be used in epoxy resins by themselves or in combination with alumina trihydrate (ATB). As shown in Chart 21 dramatic FR efficacies relative to highly loaded ATH contents can be achieved. FR resins meeting UL 94 V-O (@ 1/16") for the electrical/electronics mkt are available with these phosphorus based additives. Exolit AP 750 can be used for flame-resistant and intumescent gel coats based on epoxy resins. By adding ExoHt AP 750 to an EP gelcoat important fire dasses like DIN 5510 S4 SRl ST2 or DIN 4102 Bl can be attained with layer thicknesses above 500 pm. Exolit OP 910 can be used for filler-free formulations wherever a non homogeneous distribution of solid flame retardant is expected because of the reinforcement material. For example, DIN 5510 S4 can be achieved with ExoHt OP 910. Epoxy resins with reacted-in phosphorus and nitrogen compounds have been developed for use in printed circuit boards and for encasing electronic components. The disadvantage of these systems at present is their high price.
151
..--
~.
,=Co.
Clariant
Flame Retardancy for Thermosets - Epoxy Resins, Composites GIIISS fiber reinforced epoxy t'Bsin IlIminlltes:
Rail applications:
nvn'
DIN 5510 S4 5R2 (4 53 5R2 (4 mm'
30 parts Exolit AP 422 20 parts Exolit AP 422
NF-P 92-50 1
10 parts Exolit RP 650 50 parts Aluminum hydroxide
Electrical applications: UL 94 V-O (1.6 mm'
20 parts Exolit AP 422
UL 94 V-O (1.6 mm)
10 parts Exolit RP 650 (printed circuit boards) Chart 22
For high-performance composite materials, e.g. structural components, epoxy resins have become accepted as a material of construction. Brominated epoxy resins are used in the aerospace industry e.g. in interiors, for sidewalls and floor panels. The use of powder additives should remain at a minimum, in order not to impair the mechanical properties. Halogen-free formulations based on ammonium polyphosphate or red phosphorus are being developed (Chart 22). By adding 3-6% red phosphorus to epoxy resin, halogen-free flame resistant printed circuit boards un be produced.
For electro-casting compounds red phosphorus can be combined with aluminum hydroxide.
v.
Conclusions
1. Phosphorus-based products have excellent potential as "halogen-free" flame retardants for a broad range of polymeric applications. 2. Cost effective chemistries and formulation sophistication for engineering thermoplastics, polyolefins, and thermoset resins are available. 152
VI. References 1. ®Suntest - UV radiation test reflective of outdoor exposure. Radiation intensity: 70 - 80 W1m2 (290 - 400 nm). 2. FRl = Spinflam® MF82 from Montell. 2. FRl = Amgard® NP from Alhright & Wilson. 4. FRl = Budit 3077 from Budenheim.
153
FIRE RETARDANT CHEMICALS ASSOCIATION. SPRING CONFERENCE. NEW ORLEANS 1999.
Fires in the home. The Alliance for Consumer Fire Safety in Europe. Robert A. Graham MBE MIFireE Executive Director.
Preventing accidental fire in the home is a major and complex challenge. There exists a temptation to define it as a problem of careless behaviour and ignorance. To do so, however, is to over-simplify the matter and ignore reality. The wide range of possible causes of household fires, the householder's opportunity to intervene at varying stages of the process leading to an outbreak and the diverse backgrounds, abilities and knowledge of the householder, give an indication of the elements contributing to the complexity of determining an effective fire safety strategy. In considering the choice of preventative measures, the vulnerability of certain groups (e.g. children) and the likely acceptability and effectiveness of the proposed measures are important factors. In considering fire hazards, the possible fire causes, the susceptibility of some materials to ignition, and the speed of fire development are important factors to take into account when deciding protective measures. The Alliance for Consumer Fire Safety in Europe (ACFSE) strategy has four complementary strands to address this: • Education and publicity. • Consumer product safety. • Information gathering and monitoring. • Standard setting and Harmonisation. I would briefly like to elaborate on these :
The educational and pUblicity approach, is very effective with schoolchildren, providing
them with an understanding of fire dangers and basic skills in fire safety. With adults,
however, measures requiring frequent action on their part are likely to be less acceptable
and therefore less effective. Among the pressures of daily life. which in many at risk
households can be extreme, they can be easily forgotten or overlooked.
The failure to replace spent smoke alarm batteries is an example of this problem.
This approach has its limitations, but it is believed that a consistent long term campaign
can change behaviour and reduce fire deaths and injuries.
155
'.
Due to the sterling work of other agencies e.g. fire brigades, fire safety organisations and the Home Office taking place in the UK, we see no point in duplicating efforts planned or underway. But we work to support and enhance such efforts wherever possible.
In wider Europe however, there are few parallels to such initiatives, Therefore, a clear need exists for ACFSE to fill in sharing this knowledge and experience, and this is already underway. Public education is a key and our ability to facilitate it will be invaluable to our efforts to improve fire safety and reduce death and injury throughout Europe. ACFSE is based on the premise that a balance needs to be struck between efforts involving long term educational campaigns to modify peoples behaviour and those involving the safer design of consumer products, which is our second strand and in some instances might be easier, quicker and more effective in reducing fire deaths and injuries than any other course of action. The approach to fire safety through safer product design - the environmental approach has much to commend it. The impact is permanent, the benefits can be achieved in a relatively short time, and the improvements can affect all sections of the population including those least susceptible to the educational approach. There have been many examples of this. One that I have had a particular interest in and is particularly relevant is a comparison of furniture upholstered with the safer combustion modified foam and untreated upholstery materials.
In 1997 in the UK there were 3 fires where combustion modified foams were the materials mainly responsible for the development of fires. These fires resulted in 1 death and 5 injuries. Other foam upholstery was responsible for the development of 1398 fires and accounted for 40 deaths and 535 injuries. As we all know, in most accidental fires, it is the contents of the home (i.e. consumer products) that are the items first ignited and that provide the materials responsible for the development of the fire. The design, construction and use of consumer products has therefore a major influence on fire safety in the home. The education of consumers is vitally important, but equally so is the education of manufacturers on the consequences of fires involving their products, from whatever cause, The third strand of our strategy will be to monitor the cause and effect of domestic fires on an international basis. Those of us in the fire fighting business know what is happening out in the world, but we need the facts and figures to back up our hunches and help in determining the areas that should be the focus of our actions. We need information that is detailed, reliable and comparable. We intend to carry out a poll of Europe in the coming year. This information will be analysed and desseminated by various means and will assist in determining the emphasis of our actions.
156
The fourth area that we are focussing on is Standards. This is in tenns of setting, testing and hannonisation.
We decided that we need to be active in the standard setting processas it exists today.
This has been welcomed by many as ' a voice for the consumer'. We are reviewing
current standards and placing ourselves in a role in the development of new standards.
We need to examine the methods of test used in the standard setting process. We all
know for example that fire bums vertically, yet many standards call up horizontal tests.
Fire tests for materials must reflect these basic realities of fire.
Repoducibility may be important from a laboratory technicians point of view, but the
emphasis of fire tests for consumer products must be first to simulate conditions of use
and then to seek reproducibility.
Hannonisation of standards is a fact of life. We cannot expect or rely on manufacturers to
remember the reasons for effective fire safety standards in the past, or to recognise the
need for them in the future. To ensure that past lessons do not have to be re-learned, at
the cost of lives lost and people injured, a constant monitoring of consumer product fire
safety is necessary. Our aim is to make effective fire safety standards a prerequisite of
hannonisation, rather than a casualty of it.
In this respect the activities of the Alliance is different to other fire safety initiatives in
that having identified a problem we will prepare cogent arguments for improvements.
These will be presented at international level to manufacturers, regulators, standard
making bodies, enforcement agencies, fire brigades, retailers and rental suppliers,
insurance companies and of course consumers and consumer organisations.
So what have we achieved since our inaugural meeting in London on the 21 November
1998 ? We have finnly established the Alliance in the United Kingdom. We have raised awareness of both the ACFSE and fire safety issues and we are a long way down the road to completing the first stage of our continental roll-out. We now have a strong membership base in the UK. Moreover, we have received extremely positive feedback and numerous letters of endorsement from organisations representing a wide spectrum of interests. We have received support not only from fire officials, the fire industry and scientists, but also from consumer groups, manufacturers, standards making bodies, and most importantly, the British Government. Our list of core members includes BRKlFirst Alert, the Chief and Assistant Chief Fire Officers' Association, the Fire Protection Association, The Loss Prevention Council, The National Fire Safety Charity for Children, the Confederation of European Fire Protection Associations, the Bromine Science and Environmental Forum and the Consumer Policy Committee of the British Standards Institution. The British Fire Consortium and the National Association of State Fire Marshals are both advocate members. Several
157
internationally renowned scientists have agreed to act as scientific advisors to the Alliance, including Or Frederick Clarke, Dr Margaret Simonson, Dr Jurgen Troitzsch, Dr Don Christian, Dr David Purser, A G Smith, Dr Keith Paul and Arthur Monks. Having laid such strong foundations for the Alliance, our next step was to raise our profile among a wider audience. To this end, we created a website and initiated media relations activity. The web site has been designed to be a source of knowledge and practical information for those interested in consumer fire safety and the ACFSE. On-line information includes the ACFSE mission, an update of the latest news and fire stories from around Europe, and details of our membership. The web site is at present being developed to accommodate the Alliance's expansion into Europe. For those of you who wish to visit the site, the address of the site is ACFSE.com. Our media campaign has produced a great deal of coverage, so far reaching an estimated audience of 20 million people in the UK. We have created press packs and syndicated radio interviews and these have helped us to gain national newspaper coverage, approximately 20 regional press articles, 6 features in specialist press publications, and coverage on over 50 radio stations around the UK. So what has been the impact of this media activity? • We have established ourselves as a credible voice and we have highlighted the importance of consumer product fire safety among a wide audience. • We have generated debate and interest among the general public, the fire industry, consumer organisations, manufacturers and standard making bodies. • This in turn has led to a project partnership with the UK government focusing on the fire safety standards of televisions. We are also advising the Department of Trade and Industry on aspects of consumer fire safety. • As a direct result of our activity, the London Fire brigade has undertaken research into the impact differing international standards for consumer products We have begun the continental roll-out of the Alliance and are confident that the momentum of our success to date will be increased. Our focus for 1999 is on The Netherlands, Germany, Sweden and France. In the Netherlands, we have secured a number of key core memberships and are moving towards an official launch. Our cause is being advanced by our Country Director, Rene Hagen, the Assistant Fire Chief of the Amsterdam Municipal Fire Department. Mr Hagen is one of the most respected firemen and authors in his field. In Germany our launch is set for late February. We have captured the interest and commitment of the country's leading fire safety stakeholders, including fire chiefs of major brigades. To date, our mandate has met with universal international approval and I anticipate no difference in the reception that we will receive in both Sweden and France.
158
We realise that it is essential to build on the work that we have already carried out. To this end we will continue our efforts in the UK to raise consumer fire safety standards. Moreover, we need to firmly establish the Alliance on the Continent in major markets across the European Union. As European Institutions grow in importance, and more and more legislation is drafted at the EU level, there is a need for a body at this level to focus on the specific issue of consumer fire safety. By bringing together a wide range of interested parties from a number of EU countries, the Alliance will be able to learn how best to tackle the issues of concern by sharing knowledge, experience and best practice.
If a measure of success is the depth, width and strength of an organisation's membership, then we are heading in the right direction. Our members are the key to our future success. If a measure of success is acceptance by Government, then through our partnership with the DTI and the Home Office, we are on the right track. The objectives of the ACFSE are to raise fire safety standards across Europe, and at the same time, to educate the public about fire safety. Our measure of success will be an upward harmonisation of fire safety standards in consumer products throughout Europe and a reduction in deaths caused by fires in the home, particularly consumer product related fires. These are early days, but already we are progressing towards our goals. We rely on the support and membership of organisations such as those that you represent. Our fire safety goals and your marketing agendas are in accord. The development of a fire safety culture at all levels of society serves our common purpose. As the saying goes, "a rising tide raises all boats". We have set that tide rising in Europe.
159
The Alliance for Consumer Fire Safety in Europe Fighting Fire with Knowledge
MISSION
It has been estimated that each year in the European Union, 80,000 people will be injured in fires and of these, 4,000 will die. Because most life-threatening fires occur in the home, in one way or another they involve consumer products. The mission of the Alliance for Consumer Fire-Safety in Europe (ACFSE) is to reduce those numbers by bringing together parties that are dedicated to the goal of preventing accidents, injury and death resulting from fire.
FOCUS Given their all-pervasive nature, it is small wonder that consumer products have a major impact on the development of life-threatening fires. This can be as a result of misuse, design or just simply as a source of fuel for a fire. Indeed in the wrong context many consumer products can and do contribute detrimentally to the ignition, intensity and spread of a fire.
GOALS • Educate consumers as to the potential hazards of fire in the home, and highlight
practical steps that can be taken to minimise such fire risk;
• Raise awareness of fire safety in consumer products among retailers,
manufacturers and decision makers;
• Advocate effective fire prevention levels for consumer products; • Maintain an overview of the causes and effects of domestic fires, and promote the development of detailed and compatible fire statistics across Europe.
ACTIONS Bring together a wide range of interested parties from a number of EU countries to share knowledge, experience and best practice in dealing with fire risk and consumer products. This effort also involves working to establish more usable and comparable data on fire statistics involving consumer products. Work with fire brigades, voluntary code associations, manufacturers, governments and other agencies to enhance co-operation and integrate Alliance efforts with those of other agencies pursuing fire safety objectives. Raise consumer awareness of the importance of fire safety through specific campaigns targeting 'at risk' members of the community. For this reason, campaign efforts will include the support of fire safety educational initiatives for school children and those in assisted living situations. Efforts will also include supporting increased safety through better product designs where improvements can affect all sections of the popUlation including those least susceptible to the educational approach. Actively engage in the standard setting process to ensure that the interests of fire safety for consumers is adequately represented, to promote the adoption of high levels of fire safety, and to establish fire prevention as a priority in future discussions of harmonised product safety standards.
160
For more information on Alliance activities, opportunities to participate, membership or to receive a free copy of the Alliance Charter, please call (44) 171 4046047, or write to PO Box 21394, London WCIA 2TN (in the UK) or BP 89, B-I040 Brussels 4, Belgium or you can contact the web site at:
ALLIANCE MEMBERS Alliance is looking for membership from entities and individuals with the following backgrounds: • Fire brigades and professional fire organisations • Industries associated with fire prevention/the aftermath of fire The insurance industry Manufacturers of home fire fighting/detection equipment Manufacturers of fire prevention materials • Regulatory bodies associated with fire safety • Consumer organisations • Prominent Scientists with credentials in the causes and results of fires Initial Members Include: The Fire Protection Association UK (FPA),the :xxx (CFPA), The Loss Prevention Council, BRKlFirst Alert, The Chief and Assistant Chief Fire Officers' Association UK (CACFOA), the Fire Brigades Union UK (FBU), The Bromine Science and Environmental Forum (BSEF), The National Fire Safety Charity for Children UK, The National Association of State Fire Marshals USA (NASFM)
Robert A. Graham MBE M.I.Fire E.
ACFSE Executive Director
Bob Graham is the fonner Assistant County Fire Officer of the Greater Manchester (UK) Fire Service with 31 years of service and a wide degree of experience in all areas of fire service activities. For 13 years he was responsible for Fire Safety and Investigation as well as operational command of a fire brigade comprising 41 stations and over 2,000 professional fire-fighters protecting a population of2.5 million. • For over 10 years he was Secretary of the Chief Fire Officers Fire Safety Technical Committee and was their representative on Government and British Standards committees dealing with fire related issues. • He has held an appointment on the governments Building Regulations Advisory Committee and is a serving member of the Fire Advisory Panel.
• An experienced Fire Investigator, he was responsible for the investigation on behalf of Her Majesty's Coroners of almost 1,000 fire deaths including the major disasters of the F.W. Woolworth's fire, Manchester, 1979 and the Manchester Air
Disaster of 1985.
161
• He has been a lecturer on Fire Safety at the Fire Service College and is a frequent speaker at national and international conferences on domestic fires, Fire Safety codes and Standards and the application of fire Legislation. • He played a key role in helping the Chief and Assistant Chief Fire Officers' Association push for the successful adoption of higher flammability standards in upholstered furniture in the UK. In 1989, he was honoured by Her Majesty The Queen for his years of work in the Fire Service, and appointed a Member of the Order of the British Empire (MBE).
162
FIRE RETARDANT REAGENT IN THE COMPOSITE BOARD
INDUSTRY
David Galsworth y1 and Jan Voortmans 2 1) A.O.I. Technical Applications, 2) F-Stop.
SUMMARY
This paper presents information on a new product for imparting fIre resistance to panel products. The product, marketed under the trade name 'Siriono', is an aqueous based reagent, having a pH that is largely neutral. The product is considerably more 'user friendly' compared with other available reagents, and has signillcant advantages over other products when used in panel manufacturing processes. The product can tolerate higher platen temperatures compared with conventional frre retardant products, and therefore signillcant improvements in productivity can be realised. Panel products with Class 1 resistance to spread of flame can be produced at addition levels of 5 - 6%. For MDF, in common with all frre retardant products, higher resin levels are required in order to achieve acceptable physical board properties. However, at similar resin addition levels, Siriono has signifIcant advantages over other FR products on the market. Internal bond strength is similar to that of conventional products made without FR additives, and thickness swelling is much improved. There is also evidence that the free formaldehyde content of panels is reduced. As such, Siriono offers the panel products industry a real opportunity to meet the increasing demands for FR products without signifIcantly compromising profItability.
INTRODUCTION Fire resistant (FR) products have to date only fonned a small proportion of the total output of the panel products industry. Furthennore, the production of such products has been limited to relatively few manufacturers. Although FR products represent a potential added value market for panel producers, few have sought to enter this market. A key factor has been the reagents that have to date been available for imparting resistance to spread of flame to products. These have largely been comprised of ammonium sulphates and phosphates, or boron-based compounds. These compounds are commonly strongly acidic in nature, and as such they present both handling problems and difficulties in the manufacturing process. Typically platen temperatures have to be reduced, with subsequent reductions in output. In addition, for MDF in particular, significantly higher resin addition levels (in excess of 20%) need to be used in order to achieve acceptable strength properties of panels. Even at such resin addition levels, thickness swelling properties in particular can fall outside of accepted limits for standard products, and internal bond strengths, although above specified minima for standard products, are often also reduced. Technically this is not a problem, since FR products are currently only required to meet specifications related to resistance to spread of flame. However, manufacturers would prefer to maintain the physical properties of panels. Recent revisions to building and construction codes of practice have increased the requirement for construction materials to meet minimum specifications with respect to resistance to spread of flame. Consequently, panel producers have had to revise their attitudes towards the production of FR products. Many producers now recognise that they may either have to consider FR products as part of their product range, or expand existing production levels, even to maintain existing markets. It was evident therefore that the panel products industry was faced with increasing demand for FR products. However, the ability of the industry to respond effectively to this increasing demand was hampered by the limitations of the available FR additives. There was thus clearly 163
-
an FR product which addressed many of the key problems that have to date hindered expansion in the panel products industry. In developing a new product, the following issues were considered to be important: • The product should be available as an aqueous-based system. • The pH of the product should be near neutral. • The product should be capable of tolerating higher I near normal platen temperatures. • The required resin addition levels should be lower than those of other FR products in order to maintain panel physical properties. • The product should be able to give Class I resistance to spread of flame at competitive addition rates. This paper presents an overview of work that has been conducted to date to demonstrate the suitability of 'Siriono' as an effective, 'user-friendly' FR reagent for the panel products industry.
LABORATORY & PILOT PLANT STUDIES In order to convince the panel products industry to consider using Siriono, it was clear that some evidence of the potential benefits of Siriono would be required. Accordingly, a research programme was initiated. In the first instance the use and suitability of the product in particleboard was investigated. Subsequent studies were focused on MDF. Particleboard Studies Work on particleboard was conducted by the Wilhelm-Klauditz Institut. At an early stage it was clear that a key difficulty that needed to be overcome was the additional water added to the furnish with the retardant. The solution was a pre-impregnation step prior to drying of the furnish. This involved mixing chips in a blender whilst simultaneously spraying the aqueous FR solution onto the chips. Thereafter, the chips were treated as normal i.e. drying followed by blending with resin. In this way, furnish moisture contents prior to pressing were kept within acceptable limits. It was evident that the pre-impregnation step resulted in a uniform distribution of the FR product in the panel. Evaluation of test panels for resistance to spread of flame indicated that a Class I grade of product could easily be achieved at addition levels of 5% for the FR reagent. Importantly, at this FR addition level, increases in resin levels were not required in order to maintain the physical properties of panels.
MDF Studies Initial discussions with MDF manufacturers indicated that the blowline would be the preferred point of application for the FR product. However, manufacturers expressed concern about the possible interactions of the FR product with resin, which might ultimately result in blowline blockages or other problems in the process. Accordingly, pilot scale trials were undertaken at The BioComposites Centre to determine whether introduction of the FR reagent into the blow line might present problems. Additional studies were also undertaken to investigate the effect of the FR reagent on the gelling behaviour ofUF-based MDF resins.
164
Pilot scale trials The perfonnance of the FR reagent was investigated with two resin types: El and E2. Softwood chips, comprised predominantly of spruce, were used as the wood raw material for the trials. Resin was applied to the refined fibre at an addition level of 12%, wax emulsion at 0.8% and FR reagent at 6.25% (all addition levels expressed as 100% solids on oven dry mass of fibre). Resins were applied at 57% solids, wax at 60% solids, and the FR reagent at 38% solids. Resin and FR reagent were injected directly into the blowline through separate injection ports. Hot press platen temperatures were set to 180°C. Target sanded thickness and density of boards was 12mm and 750 kg/m 3 respectively.
Fire retardant solution was successfully injected into the blowline on a continuous basis. No blockages occurred during running, and inspection of both the blowline and drier after the trials revealed no abnonnal deposits. Boards containing the FR reagent and both the E 1 and E2 resin types were successfully manufactured. Evaluation of the boards for resistance to spread of flame indicated that both types comfortably met the requirements for Class 1 FR products. However, evaluation of the physical properties of panels clearly indicated that inclusion of the reagent impaired panel properties: • The internal bond strength of panels was approximately halved • The thickness swelling (after 24 hours immersion in water) of panels was increased by a factor of around seven. • The bending properties of panels were reduced by around 30%. The results suggested that the reduction in board properties was less marked with the E2 resin in comparison with the E 1 resin. It was evident therefore that, although the FR reagent did not cause significant problems in either the blowline or drier, its presence in the product did compromise physical properties. It was believed that the most likely explanation for the reduction in strength properties was that components within the fire retardant additive were promoting pre-cure of the resins during any or all of either the blow line blending, flash drying and hot pressing phases of the production process, and thereby reducing resin (bonding) efficiency. Accordingly, investigations were undertaken to shed further light on this. Resin gel time The potential interaction of the FR reagent with UF resins was investigated using methods commonly used to evaluate the perfonnance of conventional hardeners with resins. Four types ofUF-based resins were investigated: two types ofE1 resin, an E2 and an MR resin.
In the first instance the FR reagent (in the fonn of a 38% aqueous solution) was mixed with samples of each resin at addition levels between 0.5 and 2.5% (100% solids on resin solids). In each case the resin solids content of the sample was adjusted to 57% solids. The gel time of a 5g sample of each resin I FR mix was measured at 100°C. Gel times longer than 10 minutes (600s) were not recorded. For all resins the effect of the FR reagent on gel time was compared with that of the conventional resin hardeners ammonium sulphate and ammonium chloride.
Results are summarised in Figures la-d. It was evident that the FR reagent did have a catalytic effect on the cure characteristics of UF-based resins, though in general the effect was not as 165
strong as that of the conventional hardeners at similar addition levels. For one of the El resins investigated, the FR reagent appeared to have no effect on the gel time. E1 (1)
E1 (2)
600
600
--
..... SOO
.!!!.
Siriono
~Q) 300
...... AmChl ......
200
AmSul
G)4oo
E
(!)
--
..... soo
.!!!.
Siriono
~G) 300
...... AmChl ......
200
AmSul
G)4oo
E
(!)
100
100 0
0.5
1.5
2
0
2.5
Hardener Level (% on resin solids)
0.5
2.5
MR
E2
250
600
---
..... 200 .!!!. G) .~ 1SO
Siriono
...... AmChl ......
I-
100
AmSul
so 0
2
Figure 1b
Figure la
G) (!)
1.5
Hardener Level (% on resin solids)
-
SOO ~4oo G) ~ 300 G) 200 (!)
---
Siriono
...... AmChl ...... AmSul
100 0
0.5
1.5
2
2.5
0
Hardener Level (% on resin solids)
0.5
1.5
2
2.5
Hardener Level (% on resin solids)
Figure 1d
Figure 1c
Figure 1a-d: Comparison of the relative effects of 'Siriono' FR reagent and ammonium sulphate and chloride on the gel time offour UF-based resins, a) El resin, b) El resin, c) E2 resin, d) MR resin. Whilst indicative of the likely effects that the FR reagent could have on resin cure in the MDF process, it was believed that the conventional resin gel test might not give a true indication of the effect of the reagent on resin cure in the process. This was for two reasons. Firstly, in the production process the reagent is added in significant quantities i.e. as much as 50% of the resin solids. Secondly, once out of the blowline, the reagent is likely to be present in near solid phase during drying, forming and hot pressing. Given the above, a second set of gel tests were performed, this time aimed at investigating the effect of dried solid FR reagent on resin gel time. The FR reagent was added at a rate of 25% on resin solids. As before, the effect of the FR reagent on gel time was compared with that of the conventional resin hardeners ammonium sulphate and ammonium chloride (both added to the resins in solid phase at the same rate of addition). Results are summarised in Table 1. It is evident that the FR reagent had a significantly enhanced catalytic effect on resin cure when added to resins at higher rates and in the solid 166
phase. This contrasted with the behaviour of the conventional catalysts, which showed a reduction in their catalytic effect when added to resin in the solid phase, even at ten-fold higher addition levels. Table 1: Gel times (seconds) for four UF-based resins in the presence of 'Siriono' FR reagent, ammonium sulphate and ammonium chloride, all added in solid phase at a rate of
25%. Resin Type
'Siriono'
Ammonium chloride
Ammonium Sulphate
E2 MR El (1) E2 (2)
37 (98) 81 (iOOl 90 (i54l 600 (>600)
87 (72) 79 (91) 124 (115) 124 (134)
135 (84) 86 (87) 90 (109) 240 (177)
Figures In parentheses are the gel times obtained using the reagent / hardener In solution at an addition rate of 2.5% on resin solids.
The results thus suggested that the FR reagent did have a significant catalytic effect on resin cure, and that unlike conventional catalysts, the effect was more pronounced at addition levels greater than 3%, and when the reagent was in the solid phase. Given that in the partic1eboard studies no significant increase in resin levels were required in order to maintain panel properties, the results suggest that in the MDF process the bulk of the resin pre-cure initiated by the FR reagent probably occurs in the blowline and drier. MILL TRIALS Particleboard To date full scale production trials have been limited to MDI bonded partic1eboards. In these trials the pre-impregnation approach was not adopted. Instead, attempts were made to mix the resin and FR retardant prior to blending with the wood chip furnish. Initial results were not promising, as the reagent tended to promote pre-cure of the MDI resin. However, the FR reagent was reformulated, and trials were successfully conducted. Panels containing 5% FR reagent easily met Class 1 FR requirements, whilst other board properties were not significantly compromised. MDF Full scale production trials were conducted at two European MDF mills, one running a continuous press, the other a multi-daylight press. 'Siriono' FR reagent was injected into the blow line at 38% solids, at an addition level of 5.4% (solids on oven dry fibre mass). In the light of the results obtained from the pilot scale trials, resin addition levels were set to those typically used for other FR reagents.
For all trials it was evident that platen temperatures could be maintained at higher levels than those typically used for other FR reagents. As a consequence, production rates were increased by up to 50% in comparison with other FR reagents. Furthermore, the internal bond strength of panels was equivalent to that of conventional panels made without FR reagent. However, thickness swelling properties, whilst considered to be acceptable by the manufacturers, were higher than those typically found in FR-free panels.
167
Evaluation of the panels for resistance to spread of flame indicated that they easily met Class 1 FR requirements. One additional benefit arising from the use of the FR reagent appeared to be that the free formaldehyde content (determined by the perforator method) of the panels was reduced in comparison to conventional panels. CONCLUSIONS 'Siriono' FR reagent appears to offer a number of advantages to the panel products industry compared with conventional reagents. The fact that it can be applied in an aqueous state, and has a near neutral pH, means that the product can be handled and used in relative safety. The product can impart acceptable resistance to spread of flame to panel products at competitive rates of addition. Furthermore, the physical properties of panels are not compromised to the same extent as with other FR products. Perhaps most importantly, 'Siriono' has improved tolerance to high temperatures, such that significant productivity improvements can be realised compared with other FR products. Although 'Siriono' appears already to offer the panel products industry significant advantages, F-Stop continue to search for further improvements. Research is currently focused on investigating the suitability of the product for PF -bonded panel products, and on whether the product can be combined with resin types other than MDI, to give a single step addition option for the particleboard industry in particular. ACKNOWLEDGEMENTS The authors would like to thank the following organisations and persons for their invaluable contributions: Andy McLaughlin & Jamie Hague, The BioComposites Centre, University of Wales Bangor, UK. Professor Stevens, University of Ghent, Belgium. Wilhelm-Klauditz Institut, Braunsweig, Germany.
The above paper was entered as part of the proceedings to the 2"" European Panel Products Symposium at Llandudno 20 ch October 1998 and presented by David Galsworthy with Dr. Jeremy Tompkinson in the chair.
168
SYNTHESIS, THERMAL PROPERTIES AND APPLICATIONS TO POLYPROPYLENE OF TRIS (2,2-DIBROMOMETHYL-3-BROMOPROPYL) PHOSPHATE (TDBP) OU YUXIANG
PENG ZHIHAN
National Laboratory of Flame-retarded Materials Beijing Institute of Technology Beijing 100081 The People's Republic of China ABSTRACT The synthesis, thermal stability and applicationa to polypropylene(PP) of tris(2,2 dibromomethyl-3-bromopropyl) phosphate were studied. The initial decomposition tem perature of TPBP is 60'C and 80'C higher than those of unstabilized hexabromocy c1ododecane (HBCD) and tris (2, 3-dibromopropyl) isocyanurate (TBC) reapectively. There exist some aynergiatic effects between TDBP and SbaO, in flame-retarded PP at lower loadings of TDBP, but this synergism is deteriorated when the add-on of TDBP is increased. The experimental results demonstrated that TDBP has satisfactory thermal stability, high flame retardant efficiency, excellent proceasability, and moderate effects on physico-mechanical performances of flame-retarded PP. Key words I Tris(2,2-dibromomethyl-3-bromopropyl) phosphate Flame-retarded PP
Since J. W. Lyons described the superior efficiency of bromine-phosphorus flame retardants, they have drawn extensive attention of acientistaCl-tl. But there were not many literatures on their synthesis, properties and applications to polymers except polyurethanes and unsaturated polyeaters. The authors syntheaized a bromine-phoapho rus £lame retardant-TDBP and studied its thermal propertiea and applications to PP. In addition, the aynergistic effects between TDBP and SbaO. in PP were preliminary ex plored. The further work is still on progress. 1 Raw Materials and Apparatus
1. 1 MaiD Ra" Materials pp, PPH-M-IOSB, MFI-l.18g • min- I , produced by Yueyang Petroleum Chemi
169
cal Works. Sb,O., 0 grade, produced by Haikwangshan Mining Administration. TDBP, purity~95Y., synthesized at author's laboratory. Tribromoneopentyl alcohol (FR-513), provided by Dead Sea Bromine Corporation.
Other chemicals were all purchased from the market in China. 1. 2 Main Apparatus ZSK-30 twin-screw extruder, manufactured by WP Corporation in Germany. HC-2 LOI tester, manufactured by Jiangning Analytical Instrument Factory. TA 2000 Thermal Analyzer, manufactured by Dupont Corporation in USA. TA 5 Thermal Analyzer, manufactured by Perkin-Elmer Corporation. The mechanical performances of flame-retarded pp were determined by the Re search Institute of Yueyang Petroleum Chemicals Works and the used apparatus are not listed here. 2 Syntbesls
or TDBP
TDBP waas synthesized via the reaction of tribromoneopentyl alcohol with phos phorus oxychloride in the presence of Lewis acid (catalyst) and organic amines (acid trapping agent),and 1,1,2,2 ,-tetrachloroethane or dioxane was used as solvent. The optimized reaction conditions may be as follows I molar ratio of alcohollPOCl. = 3. 0 I 1.0, amount of catalyst reaction temperature
O.lmol/mol POeI,. amount of solvent
lOO'C, reaction time
500mi/mol alcohol.
(h. The obtained product was identified
by IR. IfINMR and elemental analysis. The yield of crude phosphate was greater than 9SYo and with a melting point of 180-182'C, purity>9SYo.
~H.ur
3 nrlllC-
I-TDBP,2-PP with 10Y. of TDBP/Sb.O••
3-PP with 10,", of TDBP,4-PP
J I
-= ..
i
• ..t.----~.•~--~~--~..~---_~----..~--.-..~---d"" ' ......, ..... l-a
Fi,.8
..... 1.., ••. _
U
1,..\ . . . .
DSC curve. of PP. PP with TDBP and pp with TDBP/Sb.O.(3/l)
I-PP with 5,", of TDBP/Sb.O•• 2-PP with 10,", TDBP.
3-PP with 10Y. of TDBP/Sb.O•• 4-PP with 20,", of TDBP/Sb,o•• 5-PP
176
Bromine-free flame retardant polycarbonate
AKIONODERA Idemitsu Petrochemical Co.,Ltd Polymer applications Development Laboratory
l.introduction Polycarbonate(pC) is the excellent resin of transparency, heat resistance, impact strength and self extinguishment properties and is widely utilized in variety of automobiles, office equipment and daily necessaries. Idemitsu Petrochemical Co., Ltd. has produced polycabonate resins (IDEMITSU POLYCABONATE~)
in original continuous process that is one of the three polycarbonate processes
in the world since 1969. IDEMITSU
POLYCABONATE ~
is integrated production from Crude Oil,
and Idemitsu Petrochemical has the approval of ISO 9002 and ISO 14001 to guarantee products quality and environment. In rise of the environmental consciousness in the recent years, it has raised an issue to generate very poisonous dioxins and furans in combustion of polymers. The brominated flame retardant additives that are contained to give noncombustibility on resin are thought one of the causes. The European environmental regulations such as Blue Angel(German) and TCO'95(Sweden) prohibit additions of halogenated organic compounds, and some large office machinery companies that came out with consideration of the environmental problems as the enterprise posture have voluntarily used halogen-free materials. We, Idemitsu Petrochemical have developed some bromine-free flame retardant polycarbonate resins targeted for business equipment and small appliances. These flame retardant resins are environmentally friendly and comply with stringent environmental regulations such as Blue Angel and TCO'95. We introduce the new bromine-free flame retardant resins and those applications, and suggest the flame retardant mechanism. 177
2. Flame retardant property of Polycarbonate Table 1 shows the limiting oxygen index (LOI) that is an index of plastic combustibility. PC's LOI is more than 22 ,then it has self-extinguishment property. But, PC in which flame-retardant additives are not added cannot meet UL94-5V and V-O at thinner wall that are required for business equipment and electrical appliances. There are many sorts of flame-retardant additives for resin, but it is difficult to select them for PC that is weak for alkalis and is molded at higher processing temperature. Now, there are bromine type, metal salt type, phosphate type and silicone type in the flame-retardant additives for PC.
T a ble 1
LOI of pOlymers LOI
Polymer Polypropylene Polystyrene Acrylonitrile-Butadiene-Styrene(ABS) Polycarbonate Polyphenylene oxide
17--18 18--19 18--19 25-27 28-30
i
3. Bron;ine-free flame retardant polycabonate
3-l.Flame retarding techniques for polycabonate, polycabonate alloy materials The metal salt flame-retardant additives(organic sulfonate etc.) have been used for PC, and the phosphate flame-retardant additives have been used for PC/ABS for decades. Bromine, Salt or Phosphate and Silicon flame retarding technique are each called the first, the second and the third generation in the developed chronological order (Table 2). We think that the third technique is the most environmentally friendly because phosphate flame-retardant additives might cause water and soil pollution also. Table 3 shows the main bromine-free flame retardant materials for housings of business equipment. Still, there is no bromine-free flame retardant ABS or PS because of the technical difficulty(noncombustibility, heat resistance etc.). Judging from all properties(fluidity, light endurance etc.), we think PC/ABS and PC/PS are leading in these materials.
178
-.,J
~
1.1 COl < 1.1
8
1) FRPP; 2) PVC; 3) PTFE; 4) PP;
5) PE; 6) PVOF; 7) PPO; 8) PEEK
o·
20 16 12 8 4
24
·COl = FPI x Cl
230
0
-c
j
0
2
4
0
6
a
10
10
30 Fire Retardant (0/0)
20
40
RIGID PVC: Corrosion Damage Index (CDI)
50
231
(J
-e
o~ 0
1.
2·
3·
4·
5·
10
30
Fire Retardant (0/0)
20
Damage Index (SDI) .
40
50
Corrosion
232
Criteria have been established for litnited fire, propagation and environtnental contantination. For example for clean rooms in the setni-conductor industry (FM4910 protocol): '\-~' '. Fire Propagation Index (FPI) ~ 6 ( (no fire
propagation beyond the ignition zone); Sll10ke DalDage Index (SDI) < 0.40 (smoke contatnination limited to the ignition zone); Corrosion Da11lage Index (COl) ~ 1.1
(corrosion contaInination lim.ited to the
233
Several low smoke non-halogenated cables satisfy the FM4910 criteriaf . Highly halogenated polymers, such as PTFE, ECTFE, PVC, CPVC, also satisfy the FM4910 criteria; '.' Several ordinary plastics, such as PP and PE have been modified by fire retardants to satisfy the FM4910 criteria;
234
1"
....
,
.....
The fire retardant technology has now
matured and is expected to find its
applications in various . advanced technology fields; The concepts for FPI, SDI; and CDI now
can be extended to other fields; Environmental contamination by toxic
compounds could also be assessed in
terms of FPI times the yield of the toxic
compounds.
/;'SUMMARY