EFFECT OF FLAME RETARDANT ADDITIVES IN FLAME RETARDANT GRADE OF ABS

EFFECT OF FLAME RETARDANT ADDITIVES IN FLAME RETARDANT
GRADE OF ABS
Thesis submitted to
COCHIN UNIVERSITY OF SCIENCE AND TECHNOLOGY
In partial fulfillment of the requirements
For the degree of
MASTER OF SCIENCE
IN
BIOPOLYMER SCIENCE
By
ARJUN K GOPI
(Reg.No. 93214004)
Under the guidance of
Mr. P.V Muralidhar, Assistant manager, QA,
Bhansali Engineering Polymers Limited, Abu Road
Centre for Bio-Polymer Science and Technology (CBPST)
(A unit of CIPET)
JNM Campus, Eloor,
Udyogamandal P.O., Kochi - 683 501.
August 2015

Page | 1
Letter Head
CERTIFICATE
It is certified that the work contained in the thesis titled “EFFECT OF FLAME
RETARDANT ADDITIVES IN FLAME RETARDANT GRADE OF ABS” by
ARJUN K GOPI, (Reg.No.93214004 ) student of Centre for Bio-Polymer Science and
Technology (CBPST), ( A unit of CIPET), Kochi has been carried out under my/our
supervision , in partial fulfillment of the requirements for the degree of Master of
Science in Biopolymer Science. No part of the work reported in this thesis has been
presented for the award of any degree from any other institution.
Signature of
Supervisor(s)
Name(s)
Designation (s)
Department(s)
Place
Date

Page | 2
CERTIFICATE
This is to certify that the project entitled “EFFECT OF FLAME RETARDANT
ADDITIVES IN FLAME RETARDANT GRADE OF ABS” is an authentic record of the
project work done by ARJUN K GOPI, (Reg No: 93214004) under the supervision
and guidance of Mr. P.V Muralidhar, Assistant manager, QA, Bhansali
Engineering Polymers Limited, In partial fulfilment of the requirements for the
Degree of MASTER OF SCIENCE IN BIOPOLYMER SCIENCE.
Place:
Date: Signature of Training In-Charge
Principal
Submitted to viva-voce examination held on…………………………… at C.B.P.S.T , Eloor
Examiners:
1.
2.

Page | 3
DECLARATION
I hereby declare that the work presented in this thesis entitled “EFFECT OF FLAME
RETARDANT ADDITIVES IN FLAME RETARDANT GRADE OF ABS” is based on the
original research work carried out by me under the guidance and supervision of
Mr. P.V Muralidhar, Assistant manager, QA, Bhansali Engineering Polymers
Limited and no part of the work reported in this thesis has been presented for the
award of any degree from any other institution.
Place
Date ARJUN K GOPI

Page | 4
Acknowledgements
Though only my name appears on the cover of this project thesis, a great many
people have contributed to its production. I owe my gratitude to all those people who
have made this thesis possible and because of whom my graduate experience has
been one that I will cherish forever.
Foremost, I would like to express my sincere
gratitude to Mr. K.A Rajesh, Seniour Lecturer, CBPST, Kochi for introducing this
study to me. His guidance helped me in all the time of research and writing of this
thesis. I could not have imagined having a better advisor and mentor for my project.
I am highly obliged to Mr. S. Ranghavendra Prasad, Seniour GM (HR), Bhansali
Engineering Polymers Limited for granting me permission to do my work in this
prestigious organization. I wish to express my deep sense of gratitude and sincere
thanks to Mr. Biren Kapadia, Seniour Vice president (Manufacturing), Bhansali
Engineering Polymers Limited, Abu Road, for providing me an in-commensurable
opportunity and facilities to do my project in the organization.
I also thank my internal guide Mr. P.V Muralidhar, Assistant manager,
QA, Bhansali Engineering Polymers Limited, who provided me an endless support,
encouragement and suggestions in various stages of the development of this project. I
wish to express profound gratitude towards Mr. Amit Singh, officer R&D Bhansali
Engineering Polymers Limited, who was extremely helpful and gave their valuable
advice, guidance, suggestions and then to interest to make this project success.
It is a great pleasure to express my sincere gratitude to Dr. T O Vargheese, Assistant
professor & in-charge HLC CBPST Kochi, (A Unit of Cipet) for granting me the
permission to do enabling me to complete the work.
Most importantly, none of this would have been possible without my course in-charge,
Dr. Syed Amanualla, I would like to express my heart-felt gratitude to my Course
in-charge.
Last but not least, I would like to thank god for providing me with the abilty to
complete the graduate program. My family, friends, especially Saneesh V.S, for all
their support and love, without them I would not be able to do anything.

Page | 5
Abstract
In this study the effect of flame retardants in flame retardant grade of abs is
compared with natural ABS grade. ABS is a flammable material. It is easily burn with
high flammability value. ABS materials without flame retardant are easily burned
with a luminous yellow flame, smoking strongly and continue to burn after removal
of the ignition source. So for some particular applications we are incorporating flame
retardants into ABS. But the addition of flame retardants may leads to variation in
properties. For that I have done several physical, thermal, and rheological tests to
investigate the properties of the respective ABS grades. The results obtained was
very interesting.
ABS is commonly used in electronic housings, auto parts, consumer products, pipe
fittings, waste pipes, computer housings (electroplated on the inside), and
automotive interior and exterior trim. ABS is considered superior for its hardness,
gloss, toughness, and electrical insulation properties. Although ABS plastics are used
primarily for their mechanical properties, they also have good electrical properties
that are fairly constant over a wide range of frequencies.

Page | 6
TABLE OF CONTENTS
List of Figures............................................................................................................................9
List of Tables……………………………………………..…………………….………………………………………….……..10
CERTIFICATE…………………………………………………………………………………………………………………………1
DECLARATION………………………………………………………………………………………………………………………3
ACKNOWLEDGEMENTS…………………………………………………………………………………………………...….4
ABSTRACT……………………………………………………………………………………………………………………….……5
CHAPTER 1
INTRODUCTION, SCOPE AND OBJECTIVE………………………………………………………………………11
1.1 INTRODUCTION………………………………..........................................................................11
1.1.1 Why it is used.................................................................................................11
1.2 SCOPE AND OBJECTIVE ………………………………………………….......................................12
CHAPTER-2
LITERATURE REVIEW…………………………………………………………………………………………………….13
2.1 Acrylonitrile Butadiene Styrene (ABS Polymers)…………………………………………………..13
2.1.1 General Introduction and Historical Background………………………………………..…13
2.1.2 Chemistry and Manufacturing………………………………………………………………………14
2.1.2.1 Chemistry…………………………………………………………………………………………........14
2.1.2.2 Manufacturing…………………………………………………………………………………………15
2.1.2.2.1 Emulsion Technology…………………………………………………………………………..15
2.1.2.2.2 The emulsion-mass procedure to prepare ABS polymer………………………15
2.1.3 Mechanical Properties………………………………………………………………………………….17
2.1.4 Thermal Properties……………………………………………………………………………………….17
2.1.5 Flammability…………………………………………………………………………………………………18
2.1.6 Processing…………………………………………………………………………………………………….18
2.1.6.1 Preheating and Predrying…………………………………………………………………………18
2.1.6.2 Extrusion………………………………………………………………………………………………….18

Page | 7
2.1.6.3 Injection Moulding…………………………………………………………………………………..19
2.1.6.4 Advantages and Disadvantages……………………………………………………………..…19
2.1.6.5 Applications…………………………………………………………………………………………..…20
2.2 Flame Retardant…………………………………………………………………………………………………..21
2.2.1 What are flame retardants?..............................................................................21
2.2.2 Why do we need flame retardants?..................................................................21
2.2.3 What are the benefits of flame retardants?.....................................................21
2.2.4 Does the presence of flame retardants increase the toxicity of smoke?.........22
2.2.5 How does a fire develop?.................................................................................23
2.2.6 Most effective chemical action of flame retardants………………………………………24
2.2.7 What are the main families of flame retardants?.............................................25
2.2.7.1 Brominated Flame Retardants (BFRs)……………………………………………………….26
2.2.7.2 Phosphorous flame retardants…………………………………………………………………26
2.2.7.3 Nitrogen flame retardant…………………………………………………………………………27
2.2.7.4 Intumescent coatings……………………………………………………………………………….27
2.2.7.5 Mineral flame retardants…………………………………………………………………………28
2.2.7.6 Halogen-free Flame Retardants……………………………………………………………..…28
2.2.7.7 Other Flame Retardants - Borates, & Stannates……………………………………….29
CHAPTER-3
METHODOLOGY……………………………………………………………………………………………………………32
3.1 Materials……………………………………………………………………………………………………………..32
3.2 Material Formulation…………………………………………………………………..………………………34
3.3 Preparation of material………………………………………………………………………………………..34
3.3.1 Dry blending………………………………………………………………………………………………….34
3.3.2 Extrusion…………………………………………………………………………………………………….…34
3.3.3 Injection Moulding………………………………………………………………………………………..35

Page | 8
CHAPTER-4
EXPERIMENTAL WORK………………………………………………………………………………………………….36
4.1 Testing and Analysis Procedure…………………………………………………………………………..36
4.1.1 Pendulum Impact Test………………………………………………………………………………….36
4.1.2 Flexural test………………………………………………………………………………………………….37
4.1.3 Flammability test………………………………………………………………………………………….37
4.1.4 Heat Deflection Temperature (HDT)……………………………………………………………..38
4.1.5 Melt Flow Index (MFI)………………………………………………………………………………….38
4.1.6 Specific gravity test………………………………………………………………………………………38
4.1.7 Tensile test…………………………………………………………………………………………………..39
4.1.8 Rockwell hardness test…………………………………………………………………………………39
CHAPTER-5
RESULT AND DISCUSSION……………………………………………………………………………………………..40
5.1 Comparison between ABSTRON IM11B & ABSTRON AN450M (FR)……………………..40
5.1.1 ABSTRON AN450M (FR grade)………………………………………………………………………40
5.1.2 ABSTRON IM11B (Normal grade)………………………………………………………………….41
5.1.3 Table description………………………………………………………………………………………….42
CHAPTER-6
CONCLUSIONS AND RECOMMENDATIONS……………………………………………………………………44
6.1 Overall conclusion………………………………………………………………………………….……………44
6.2 Recommendations………………………………………………………………………………………………44
REFERENCES……………………………………………………………………………………………………………………….45
APPENDIX…………………………………………………………………………………………………………………………..49

Page | 9
List of Figures
CHAPTER 2
Figure 2.1: Engineered plastics demand, 2001 (Freedonia Industry Study, 2002)……………….13
Figure 2.2 : Emulsion ABS polymerization process………………………………………………………………15
Figure 2.3 : Major property trade-offs for ABS with increasing rubber level………………………16
Figure: 2.4 Fire Triangle………………………………………………………………………………………………………23
Figure 2.5: the fire cycle……………………………………………………………………………………………………..25
CHAPTER 3
Figure 3.1 : Mould for Injection moulding specimen…………………………………………………………..35
CHAPTER 4
Figure 4.1 : Impact tester……………………………………………………………………………………………………36
Figure 4.2: Dimension measurement for Izod type test specimen………………………………………37
Figure 4.3: Flexural tester……………………………………………………………………………………………………37
Figure 4.4: Flammability……………………………………………………………………………………………………..37
Figure 4.5: HDT…………………………………………………………………………………………………………………..38
Figure 4.6: MFI……………………………………………………………………………………………………………………38
Figure 4.7: Specific Gravity………………………………………………………………………………………………….38
Figure 4.8 : UTM…………………………………………………………………………………………………………………39
Figure 4.9: Hardness tester…………………………………………………………………………………………………39
APPENDIX
Figure A1: Global consumption of Flame retardants..............................................................49
Figure A2: Future Trends and Innovation................................................................................50

Page | 10
List of Tables
CHAPTER 2
Table 2.1: Effect of molecular characteristics of the elastomer phase and SAN copolymer
forming the matrix……………………………………………………………………………………………………………..16
CHAPTER 3
Table 3.1: Typical properties of ABS (injection moulding grade)…………………………………………32
Table 3.2: Types, trade name, manufacturer and purpose of material for ABS…………………..32
Table 3.3: Types, trade name, manufacturer and purpose of materials for additives………….33
Table 3.4: Material Formulation…………………………………………………………………………………………34
Table 3.5: Injection moulding operation condition……………………………………………………………..35
CHAPTER 5
Table 5.1: properties of ABSTRON AN450M (FR grade)………………………………………………..…... 40
Table 5.2: Properties of ABSTRON IM11B (Normal grade)…………………………………………………..41
CHAPTER 6
Table 6.1: Recommended Fire retardants…………………………………………………………………………..44
APPENDIX
Table A1: Material testing data...............................................................................................51

Page | 11
CHAPTER-1
INTRODUCTION, SCOPE AND OBJECTIVE
1.1 INTRODUCTION
Flame retardants are chemicals which are added to combustible materials to render them
more resistant to ignition. They are designed to minimise the risk of a fire starting in case of
contact with a small heat source such as a cigarette, candle or an electrical fault. If the flame
retarded material or an adjacent material has ignited, the flame retardant will slow down
combustion and often prevent the fire from spreading to other items.
Since the term “flame retardant” describes a function and not a
chemical class, there is a wide range of different chemicals which are used for this purpose.
Often they are applied in combinations. This variety of products is necessary, because the
materials and products which are to be rendered fire safe are very different in nature and
composition. For example, plastics have a wide range of mechanical and chemical properties
and differ in combustion behaviour. Therefore, they need to be matched to the appropriate
flame retardants in order to retain key material functionalities.
1.1.1 Why it is used?
Plastics are synthetic organic materials with high carbon and high hydrogen content, they
are combustible. Flame retardants are added to polyolefins, polycarbonate, polyamides,
polyester, and other polymers to increase resistance to ignition, reduce flame spread,
suppress smoke formation, and prevent a polymer from dripping. A combustible plastic
material does not become non-combustible by incorporation of a flame retardant additive.
However, the flame retardant polymer resists ignition for a longer time, takes more time to
burn, and generates less heat compared to the unmodified plastic. The primary goal is to
delay the ignition and burning of materials, allowing people more time to escape the
affected area.
A significant change in flame retarding standards regarding the evolution of smoke as an
additional requirement is emerging and is being addressed by new materials and
formulations. Many traditional flame retardants increase smoke evolution as they suppress
flame propagation. New materials are being developed to balance flame retarding efficacy
and smoke generation. Nano clays are currently mostly used in combination with already
existing flame retardant chemistries to meet commercial flame retardant specifications and
pass tests. However, it is clear that the opportunity exists for such a technology to change
the landscape of flame retardant products in the near future.

Page | 12
1.2 SCOPE AND OBJECTIVE
 The purpose of this project was to study the function of flame retardants in polymer.
 Flame retardant systems are intended to inhibit or to stop the polymer combustion
process.
 In function of their nature, flame retardant systems can either act physically (by
cooling, formation of a protective layer or fuel dilution) or chemically (reaction in the
condensed or gas phase).
 They can interfere with the various processes involved in polymer combustion
(heating, pyrolysis, ignition, propagation of thermal degradation).
 A mixer, single screw extruder and injection moulding were used for sample
preparation. The types of the testing and analysis are as follows:
(a) Mechanical Properties
Two types of mechanical properties were conducted, that is Pendulum Izod impact
and flexural test. Pendulum Izod impact was used to determine the impact strength
of ABS sample. Flexural test was also carried out to determine the stiffness of the
ABS specimen.
(b) Flammability
Oxygen Index Test was used to determine the flammability properties of the
polymer.
(c) Thermal Properties
Heat defection temperature (HDT) was used to determine the temperature at which
it loss the rigidity.
(d) Material Characterization Test
MFI (Melt Flow Index) test was conducted to obtain the melt flow rate and to
determine the processibility of the ABS material.

Page | 13
CHAPTER-2
LITERATURE REVIEW
2.1 Acrylonitrile Butadiene Styrene (ABS Polymers)
2.1.1 General Introduction and Historical Background
The name ABS polymer is derived from the initial letters of three main monomers –
acrylonitrile, butadiene and styrene, used in its preparation. ABS is not a random terpolymer
of acrylonitrile, butadiene and styrene. Industrially important ABS polymers are two-phase
polymer systems that consist of dispersed polybutadiene (or a butadiene copolymer) rubber
particles and a matrix of styrene- acrylonitrile copolymer (SAN). The rubber particle is
grafted with styrene and acrylonitrile to enhance their compatibility with the matrix.
The fraction of rubber content in ABS is varies from 10-25% for common commercial grades
and special grades, e.g. for blending with poly(vinyl chloride) can even contain over 45%
rubber. The higher rubber content and the different type of polymer forming the continuous
phase result in the ABS polymers having a number of properties better than common grades
of high-impact polystyrenes.
Introduced commercially in the 1940s, ABS is a polymer whose sales have grown over the
years to become the largest engineering thermoplastic in the world. In 1982, the
consumption of ABS polymer in the individual Western countries varied from 0.3 to1.5kg
per person. In the U.S. alone, sales in 1989 exceeded 1.2 billion pounds. Demand in the U.S.
for engineered plastic is projected to advance four percent per year through 2006 to 1.6
billion pounds, valued at $3.11 billion. The demand for engineering thermoplastics in the
year of 2001 is shown at Figure 2.1, with ABS has the largest consumption rate (28.8%)
compare with the others.
Figure 2.1: Engineered plastics demand, 2001 (Freedonia Industry Study, 2002)

Page | 14
2.1.2 Chemistry and Manufacturing
ABS consists of two phases, a continuous phase of styrene-acrylonitrile (SAN) copolymer,
and a dispersed phase of grafted polybutadiene particles. Each of these phases contributes
unique characteristics to the polymer.
2.1.2.1 Chemistry
Each of the three monomers, acrylonitrile, butadiene, and styrene, is important component
of ABS. The fundamental repeating unit of the ABS chain is:
Common types of ABS polymers have an average composition of 21 to 27% acrylonitrile, 12
to 25% butadiene and 54 to 63% styrene. Acrylonitrile primarily offers chemical resistance
and heat stability; butadiene delivers toughness and impact strength; and the styrene
component provides ABS with balance of clarity, rigidity, and ease of processing.
Styrene and acrylonitrile can be copolymerized to form SAN copolymers, typically at a 70/30
ratio of S/AN. Like polystyrene, SAN is a clear copolymer, but with the additional
characteristics of higher chemical resistance, better surface hardness, and improved
toughness. This copolymer is a commercially significant product, with major applications in
markets such as battery cases, disposable cigarette lighters, and house wares.
ABS polymer systems typically contain between 70 and 90% SAN. In forming the continuous
phases of the ABS, the SAN contributes its characteristics of easy processing, high strength,
and rigidity, chemical resistance, and good surface hardness and appearance. The second
phase of the two-phase ABS system is composed of dispersed polybutadiene (rubber)
particles, which are grafted on their surface with a layer of SAN. The layer of SAN at the
interface forms a strong bond between the two phases, which allows the polybutadiene
rubber to add toughness to the ABS system, forming a rigid, impact resistant product. The
rubber phase is typically present in the range of 10-30%.
Manipulations of the two phases produce the range of polymer characteristics seen in the
different ABS products. The major variables of the SAN phase are the acrylonitrile level and
molecular weight. The rubber level can be varied to adjust the impact strength of the
polymer. Resin properties are also strongly affected by the rubber particle size distribution,
the molecular weight, and cross-link density of the rubber as well as by the molecular
weight, composition, and level of the SAN graft on the rubber particle surface. Normally,
ABS with high rigidity has higher styrene content. Super high impact ABS possesses higher
composition of butadiene if compare to medium impact ABS.

Page | 15
2.1.2.2 Manufacturing
ABS polymers can be prepared by mechanical blending of the individual components or by
grafted polymerization of a mixture of styrene with acrylonitrile in the presence of suitable
rubber component. There are three commercial polymerization processes for
manufacturing ABS: emulsion, suspension and bulk. The most common technique for
producing the grafted polybutadiene phase is emulsion polymerization.
2.1.2.2.1 Emulsion Technology
It is possible to produce the final product in a single step by grafting in emulsion. A typical
commercial emulsion process is shown in Figure 2.2. It involves five steps: rubber
polymerization, agglomeration, grafted polymerization, polymer recovery and
compounding.
Figure 2.2: Emulsion ABS polymerization process
2.1.2.2.2 The emulsion-mass procedure to prepare ABS polymer:-
First, part of the styrene and acrylonitrile are grafted onto the polybutadiene in emulsion.
The latex particles are then extracted into a newly added monomer mixture in the presence
of a coagulant. After separation of the aqueous phase, the partially grafted polybutadiene
forms a stable dispersion in the styrene- acrylonitrile mixture. Further polymerization is a
continuous mass process; the first stage (up to conversion of 40 to 70%) is carried out in a
stirred autoclave and the next stage in a tower plug-flow reactor. The heat of reaction is
removed by a cooling jacket. The polymerization is maintained at the boiling point. The
unreacted monomers are removed in the evacuated zone of the extruder.
The properties of ABS polymers are strongly affected by the molecular characteristics of
both the elastomers phase and the SAN copolymer forming the matrix.

Page | 16
Table 2.1 summarized the effects, which will occur under some situations. The properties of
this multi-phase system are also affected by conditions at the interface between the rubber
and the thermoplastic matrix. The effect of rubber level is extremely important, and the
major trade-offs from increased rubber level are shown in Figure 2.3. ABS polymer has low
density (1020 to 1060 kgm-3) and the bulk density of the pellets is also low, usually 500 to
600 kgm-3. The material is opaque as a result of the different refractive indices of the two
phases. The presence of the polar nitrile group results in certain affinity of the ABS polymer
for water or water vapour. An increase in the humidity content will lead to complications in
processing and to deterioration in some properties.
Table 2.1: Effect of molecular characteristics of the elastomer phase and SAN copolymer forming the
matrix
Figure 2.3: Major property trade-offs for ABS with increasing rubber level.

Page | 17
2.1.3 Mechanical Properties
The overall toughness offered by ABS materials is the prime mechanical property that
prompts most users to select ABS for their applications. The standard measure of impact
strength used for ABS is notched Izod impact strength, as measured by ASTM D256 A.
Depending on its impact strength, material is classified as very high, high or medium impact
polymer. As pointed out previously, its value determines in which class of standard product
a material belongs. Although ABS is notch sensitive, it is much less so than many other
polymers, including polycarbonate and nylon. In addition to good impact strength at room
temperature, ABS retains significant impact strength at very low temperatures. This has led
to the use of ABS in critical low temperature applications. ABS materials can deform in a
ductile manner over a broad temperature range and at high strain rates. This deformation is
accompanied by a significant whitening of the specimen resulting from craze formation and
separation of the rubber phase from the matrix polymer.
Another important characteristic of engineering thermoplastics is their stress- strain
behaviour in flexure. Such measurements are usually made using a simple supported beam
test specimen loaded at mid span according to ASTM D790. As with tensile properties, the
flexural strength at yield and flexural modulus can be used to determine the resistance of a
product to short-term loadings. They are also useful in comparing the strength and rigidity
of the many ABS products.
For many applications, multiaxial impact strength, typically measured using a falling or
driven dart, is as important as Izod impact strength. Reporting of multiaxial impact strength
is not yet common practice; however, data is now available from manufacturers for many
products. Although the two types of tests do not directly correlate, products demonstrating
high Izod impact strength in general demonstrate high multiaxial impact strength. Neither of
these impact tests produce information that is mathematically applicable to design. The
anticipated level of abuse a product will see in a particular application, combined with the
designer's experience, will determine the impact class selected.
The Rockwell hardness (RH) of products is useful in comparing the ability of the surface of a
part molded from different products to resist becoming blemished by intermittent loads.
The specific gravity of different standard ABS products does not very much. However, it
does vary significantly for many of the specialty grades and alloys.
2.1.4 Thermal Properties
The critical thermal properties for ABS are heat distortion, coefficient of linear thermal
expansion, thermal endurance, thermal conductivity, and specific heat. The most common
measure of heat distortion is the deflection temperature under load as measured by ASTM
D648. High-heat ABS, ABS/polycarbonate (PC) alloys, and ABS/styrene-maleic anhydride
(SMA) alloys all extend applications of ABS into the temperature up to 110oC at 1.8 MPa for
short-term exposures.
In general, plastics have significantly higher thermal expansion co-efficient than metals.
Consequently, in applications where parts are constrained, thermal stresses must be

Page | 18
accommodated in part design or expansion may induce failure in the part. This property is
especially important in ABS products designed for electroplating.
The thermal properties of ABS polymers are characterized mainly by the glass transition
temperature, Tg. An increase in temperature of the material leads to a decrease in the
tensile strength and an increase in the ductility and toughness. However the modulus of
elasticity in tension decreases.
2.1.5 Flammability
Basically, ABS has a low LOI index with a range of 17-18 %. ABS materials without flame
retardant are easily burned with a luminous yellow flame, smoking strongly and continue to
burn after removal of the ignition source. The high impact ABS will has a smell of burnt
rubber.
ABS grades that meet various standards for flammability performance are available. The
non-flame retardant (FR) general-purpose grades are generally classified as UL 94 HB
according to Underwriters' Laboratories Test Method UL94, and also meet Motor Vehicle
Safety Standard 302. These grades are used in applications having a reduced fire risk. For
applications requiring higher degrees of flame retardancy, ABS grades have been developed
based on alloys with PVC or through an additive approach using halogen in combination
with antimony oxide. Included among the FR grades are materials that meet the
Underwriters' UL94 V0 requirements beginning at a minimum thickness of 1.47 mm.
2.1.6 Processing
ABS material can be processed by injection molding, extrusion, blow molding or calendaring.
However, injection molding and extrusion account for more than 93 % of all ABS material
usage. ABS polymers process very easily and can be fabricated into very complex parts. ABS
requires significantly lower processing temperatures and is less sensitive to processing
conditions.
2.1.6.1 Preheating and Predrying
ABS materials are hygroscopic, and have an equilibrium moisture content of 0.3-0.4 % at
23°C and 50 % relative humidity. While mechanical properties in the finished part are not
greatly affected by this moisture, its presence during processing can affect the part
appearance greatly. Maximum moisture levels of 0.2 % are suitable for injection molding
and maximum levels of 0.03 % are suitable for extrusion of ABS materials. These moisture
levels can be reached by drying the material prior to processing in a dehumidified air drier
for 2 to 3 hours.
2.1.6.2 Extrusion
An extruder with a minimum L/D ratio of 24:1 is recommended to ensure a uniform mixing
and melt temperature over the die. A screen pack consisting of a 20- 40 mesh combination
is recommended. Single or two-stage screws are suitable. However, the latter part is
preferred since it also aids in devolatilization and results in an improved extrudate quality.

Page | 19
2.1.6.3 Injection Moulding
ABS polymers can be processed in all types of injection molding equipment, but optimum
results are obtained with reciprocating screw machines since it provides more uniform melt
and higher available pressure. Processing temperatures range from 177 to 288°C, depending
on the specific grade. Injection pressure of 69- 138 MPa and clamp pressure of 281-422
kg/cm2 of projected part surface are usually sufficient. Screw having a length to diameter
(L/D) ratio of 20:1 are recommended.
2.1.6.4 Advantages and Disadvantages
ABS, being copolymerized from three different monomers, has high impact strength and
competes well with polypropylene, although it is more expensive. Its dimensional stability is
good; it replaces die-cast metal components and can be electroplated. ABS is excellent for
vacuum forming and blow moulding for the production of articles such as fire extinguishers,
bus wheel arches, industrial containers, refrigerator shells and protective helmets. Basically,
ABS is preferred for its favorable balance of strength, toughness, high gloss, colorability,
processability and price. The balances of properties which are exhibited by ABS are not
found in any other plastics material. Specialist applications can be tailor made by
adjustment of the proportions and arrangement of the three parts of the copolymer, thus
emphasizing the character of the components. Besides the advantages, the material has
also a number of limitations. The disadvantages are as follows:
1) Limited chemical resistance to hydrocarbon and concentrated acids and alkalis.
2) It is mostly opaque.
3) Electrical properties are not outstanding; however, they are adequate for most purpose.
4) It is easily burn with high flammability value.
Specialty Grades
High Heat Grades: High-heat grades of ABS are produced by increasing the molecular
weight, and the acrylonitrile content, while reducing the total rubber present. Most recent
work has employed an additive approach.
These products have property balances similar to those of standard ABS except for
significantly improved heat resistance. They are somewhat more difficult to process because
of the higher melt viscosity, and they are relatively expensive. Alloys of ABS with styrene-
maleic anhydride (ABS/SMA) offer similar property balances with a lower melt viscosity at a
similar cost.
Chemical Resistance: One of the advantages of ABS relative to reinforced polyolefins and
high impact polystyrene is its chemical resistance. The polar nitrite groups make ABS quite
resistant to a variety of solvents and uptake of water is relatively low (<1 %). This chemical

Page | 20
resistance has allowed ABS entry into a wide variety of home appliances and some
automotive areas.
Flame Retardant Grades: Standard grades of ABS are considered slow burning polymers,
and most meet Underwriters Laboratories requirements for a UL94 HB rating. ABS can be
modified using halogenated additives to meet more stringent flammability requirements.
These flame retardant grades offer a balance of properties similar to medium-impact
standard ABS grades. Grades with high flexural modulus or with improved light stability are
also offered. Many ABS/PVC alloys also meet these flammability requirements. These grades
are important for electrical housing applications and contribute to a significant fraction of
ABS usage. Halogenated and phosphorus additives are generally used as flame retardants,
though halogenated styrene can be copolymerised into the ABS.
Clear ABS: Clear ABS is a transparent ABS material, which the basis is the matching of the
refractive indices of each of the rubber core, graft and matrix phases. Clear ABS grades use
methyl methacrylate as a fourth monomer to match the refractive indices of the other
monomers. The process is complicated by the fact that the refractive indices have to match
over the temperature range of use, so that the change in refractive index with temperature
must also match. Properties are similar to those of medium-impact standard ABS grades.
Plating Grades: ABS can be electroplated in the same process used for metals after being
prepared via a preplate system, which etches the surface using chromic acid and deposits an
electroless layer of copper or nickel, rendering the surface conductive. ABS also lends itself
to plating. Such grades are commonly used in car mirrors, headlight bezels and faucets
(taps). Chrome plated ABS faucets can be made in styles that cannot be made in metal.
These products also offer a relatively low coefficient of linear thermal expansion which
reduces stresses between the metal plate and the ABS during exposure to extremes in
temperature.
Filled ABS: A filled ABS has a higher strength, rigidity, modulus and high temperature
dimensional stability by adding glass fiber and is suitable for stressed structural applications.
This filled ABS is commonly used is in skis and applications in the automotive industry such
as car dashboard supports. Stainless steel filled ABS can be used when more effective
shielding from electromagnetic interference is required.
2.1.6.5 Applications
ABS's light weight and ability to be injection molded and extruded make it useful in
manufacturing products such as drain-waste-vent (DWV) pipe systems, musical instruments
(recorders, plastic clarinets, and piano movements), golf club heads (because of its
good shock absorbance), automotive trim components, automotive bumper bars, medical
devices for blood access, enclosures for electrical and electronic assemblies,
protective headgear, whitewater canoes, buffer edging for furniture and joinery panels,
luggage and protective carrying cases, small kitchen appliances, and toys,
including Lego and Kre-O bricks. Household and consumer goods are the major applications
of ABS. Keyboard keycaps are commonly made out of ABS. ABS plastic ground down to an

Page | 21
average diameter of less than 1 micrometre is used as the colorant in some tattoo inks.
Tattoo inks that use ABS are extremely vivid.
2.2 Flame Retardant
2.2.1 What are flame retardants?
Flame retardants are chemicals which are added to combustible materials to render them
more resistant to ignition. They are designed to minimise the risk of a fire starting in case of
contact with a small heat source such as a cigarette, candle or an electrical fault. If the flame
retarded material or an adjacent material has ignited, the flame retardant will slow down
combustion and often prevent the fire from spreading to other items. Since the term “flame
retardant” describes a function and not a chemical class, there is a wide range of different
chemicals which are used for this purpose. Often they are applied in combinations. This
variety of products is necessary, because the materials and products which are to be
rendered fire safe are very different in nature and composition. For example, plastics have a
wide range of mechanical and chemical properties and differ in combustion behaviour.
Therefore, they need to be matched to the appropriate flame retardants in order to retain
key material functionalities. Flame retardants are thus necessary to ensure the fire safety of
a wide range of materials including plastics, foam and fibre insulation materials, and foams
in furniture, mattresses, and wood products, natural and man-made textiles. These
materials are e.g. used in parts of electrical equipment, cars, airplanes and building
components.
2.2.2 Why do we need flame retardants?
Both our homes and offices contain an increasing potential "fire load" of flammable
materials because of the development of electrical and electronic equipment, and of rising
levels of comfort (furniture, carpets, toys, magazines and papers ...). The potential causes of
fires also tend to increase, especially in electronic equipment where the accelerating
processor power, electronic sophistication but at the same time miniaturisation, result in a
concentration of energy and an increase in risks of local overheating or other electrical fire
risks. Flame retardants can prevent an increase in fire risk from the growing number of
consumer and electronic goods in homes and offices. Flame retardants protect modern
materials such as technical plastics, building insulation, circuit boards and cables from
igniting and from spreading a fire.
2.2.3 What are the benefits of flame retardants?
Most people do not realise that their television set, sofa, mattress and computer are all
made essentially from plastics (originally made from crude oil), and without the inclusion of
flame retardants many of these products can be set alight by just a short circuit or cigarette

Page | 22
and become a burning mass in just a few minutes. Did you know for example, that a regular
TV set contains in its combustible plastics an energy content which is equivalent to several
litres of petrol? Flame retardants can be applied to many different flammable materials to
prevent a fire or to delay its start and propagation by interrupting or hindering the
combustion process. They thus protect lives, property and the environment. Flame
retardants contribute to meeting high fire safety requirements for combustible materials
and finished products prescribed in regulations and tests. Although fire safety can be
achieved by using non-combustible materials in some cases or by design and engineering
approaches, the use of flame retarded materials often meets the functionality and aesthetic
requirements of the consumer as well as offering the most economical approach.
2.2.4 Does the presence of flame retardants increase the toxicity of smoke?
This is a concern which is often raised. It is based on the fact that some flame retardants act
by impeding the combustion reactions in the gas phase and therefore lead to incomplete
combustion which in turn means a smoky fire. However, large scale studies have
demonstrated that the toxic hazards from a fire are more dependent on how much is
burning under which conditions of temperature and ventilation rather than what is burning.
Two cases can be considered:
1. The flame retarded (FR) material is subject to the primary ignition source: if this is a small
flame or other low energy source like a cigarette butt, the presence of flame retardants in
the material may cause it to smoulder and smoke somewhat, but will severely impede
ignition and in most cases no fire will develop. If burning is sustained, the release of heat
and the spread of flames will be severely hindered by flame retardants allowing people
more time to escape from the fire. The most significant reduction in toxic gases from fires is
achieved by actually preventing the fire, or preventing it from spreading from one item to a
whole room.
2. The flame retarded material is not the first item ignited but is involved in a fire that is
already developing: In this case flame retardants cannot prevent the ignition of the material
and it will eventually be thermally degraded or burn. However, flame retardants will reduce
the rate of flame spread and heat release. The impact of flame retardants on smoke or fire
gases also depends on the proportion of flame retarded material to the total fire load. Room
fire tests which compared a room with non-flame retarded materials to a room with flame
retarded items (TV cabinet, business machine housing, upholstered chair, electrical cables,
and electrical circuit board) revealed: The total quantities of toxic gases released by the FR
products was one third that for the non FR. Total smoke production was not significantly
different. "Because the total quantities of material consumed in the full room tests with FR
products are much lower than with non FR products, the total carbon monoxide [the
dominant toxic fire gas] emissions are thus around half with the flame retarded products,
significantly reducing the fire hazard."

Page | 23
Figure 2.4: Fire Triangle
2.2.5 How does a fire develop?
A fire can basically be split into three phases, the initiating fire, the fully developed fire and
the decreasing fire. The fire starts with an ignition source (for example a match) setting
combustible material (for example an upholstered armchair) on fire. The fire spreads, heats
up the surroundings and once the materials in the room have formed enough flammable
gases and are sufficiently hot, flashover takes place and the whole room is engulfed in the
fire. This is the start of the fully developed fire, where temperatures up to 1 200 °C can be
reached. The fire will later decrease as the available fire load is consumed by the fire or if
the fire occurs in a totally closed room the fire can die because of oxygen deficiency.
The fire triangle indicates where flame retardants can interfere in the combustion process.
On the one hand, there are materials that are easily ignitable but have a relatively small
energy content like paper on the other hand, there are materials which are difficult to ignite

Page | 24
but once ignited will release a large amount of energy like diesel fuel or many plastics. In
addition, in all fires secondary effects occur. These do not primarily determine the course of
the fire, but cause most of the fire deaths or damage to materials. These effects are:
 Smoke development
 Fire gas toxicity
 Corrosivity and contamination by soot (more relevant to materials than to humans
and particularly sensitive for electronic equipment)
However, as we all know, even materials such as wood do in fact burn vigorously,
because once ignited the heat generated breaks down long-chain solid molecules into
smaller molecules which transpire as gases. The gas flame itself is maintained by the
action of high energy radicals (that is H. and OH. in the gas phase) which decompose
molecules to give free carbon which can react with oxygen in air to burn to CO2,
generating heat energy. By their chemical and/or physical action, flame retardants
prevent or even suppress the process of combustion during a particular phase of the
fire cycle. This can be either during heating, ignition, flame spread or decomposition
(pyrolysis).
2.2.6 Most effective chemical action of flame retardants
The reaction in the gas phase: where the flame retardant interrupts the radical gas phase
combustion process resulting in a cooling of the system, a reduction and suppression of the
supply of flammable gases.
The reaction in the condensed phase: where the flame retardant builds up a char layer,
smothering the material and inhibiting the oxygen supply, thereby providing a barrier
against the heat source or already ignited flame from another source.
Less effective physical action of Flame retardants can take place by
Cooling: where the additive or chemically induced release of water, cools the underlying
substance to a temperature that is unable to sustain the burning process.
Coating: where the substance is shielded with either a solid or gaseous layer, protecting it
against the heat and oxygen required for combustion to take place.
Dilution: Chemically inactive substances and additives turn into non-combustible gases
which dilute the fuel in the solid and gaseous phases of the fire cycle.

Page | 25
Figure 2.5: the fire cycle
The Fire Cycle
 Any energy source (heat, incandescent material or a small flame) can be the initial
ignition source (1). 
 Energy transmitted by the ignition source to the polymer creates a degradation
where pyrolysis takes place (2). 
 Which are emitted to the gas phase. In the condensed phase, the result is an inert
carbonized material, called char (3).
 Pyrolysis is a process that degrades the polymer’s long-chain molecules into smaller
hydrocarbon molecules, the flammable gases (4)
 In the gas phase, flammable gases are mixed with oxygen from the air. The proper
mix of oxygen and fuel is reached in the combustion zone (5), where hundreds of
exothermic chemical reactions take place involving high-energy free radicals (e.g. H.
and OH.), fuel and oxygen. 
 A perfect combustion would theoretically produce H2O and CO2. In real life,
incomplete combustion products are also emitted during a fire (CO, PAHs, HCN, etc)
(6).
 Energy (7) emitted during exothermic reactions is transmitted to the polymer and
reinforces pyrolysis.  This allowing the reaction to sustain itself.
2.2.7 What are the main families of flame retardants?
The main families of flame retardants are based on compounds containing:
 Halogens (Bromine and Chlorine)
 Phosphorus
 Nitrogen
 Intumescent Systems

Page | 26
 Minerals (based on aluminium and magnesium)
 Halogen Free Flame retardants
 Others (like Borax, Sb2O3, nanocomposites)
2.2.7.1 Brominated Flame Retardants (BFRs)
BFRs are commonly used to prevent fires in electronics and electrical equipment. This area
accounts for more than 50% of their applications for example in the outer housings of TV
sets and computer monitors. Indeed, the internal circuitry of such devices can heat up and,
over time, collect dust. Short circuits and electrical or electronic malfunctions can occur.
Printed circuit boards also require flame retardancy properties which are often provided by
a cross-linked brominated epoxy resin polymer manufactured from tetrabromobisphenol-A
(TBBPA). In addition, BFRs are used in wire and cable compounds, for example for use in
buildings and vehicles as well as other building materials, such as insulation foams.
Bromine, like chlorine, fluorine and iodine is one of the elements in the chemical group
known as halogens. The word halogen is derived from Greek meaning ‘salt-former’; because
these elements are commonly found in nature reacted with metals to form salts.
 The effectiveness of brominated flame retardants lies in their ability to release active
bromine atoms (called low-energy free radicals) into the gas phase before the
material reaches its ignition temperature
 These bromine atoms effectively quench the chemical reactions occurring in the
flame, reducing the heat generated and slowing (or even preventing) the burning
process; thus preventing the fire cycle being established or sustaining itself.
 Brominated flame retardants dehydrogenate polymers by virtue of abstracting
hydrogen atoms needed to produce hydrogen bromide. This process enhances
charring of the polymer on expense of volatile combustible products. This
contributes to the flame retardancy of the polymer.
Often and when permitted, the addition of metallic compounds such as zinc or antimony
oxides will enhance the efficiency of BFRs, by allowing the formation of transition species,
so called metal Oxo halides, which allow the deposit of a protective layer of metal oxides.
2.2.7.2 Phosphorous flame retardants
The class of Phosphorus-containing flame retardants covers a wide range of inorganic and
organic compounds and include both reactive (chemically bound into the material) and
additive (integrated into the material by physical misering only) compounds. They have a
broad application field, and a good fire safety performance.
The most important phosphorus-containing flame retardants are:
 Phosphate esters
 Phosphonates and phosphinates
 Red phosphorus and ammonium polyphosphate

Page | 27
When heated, the phosphorus reacts to give a polymeric form of phosphoric acid. This acid
causes the material to char, forming a glassy layer, and so inhibiting the “pyrolysis” process
(break down and release of flammable gases), which is necessary to feed flames. By this
mode of action the amount of fuel produced is significantly diminished, because char rather
than combustible gas is formed.
The intumescent char plays a specific role in the flame retardant process. It acts as a two-
way barrier, both hindering the passage of the combustible gases and molten polymer
towards the flame and shielding the polymer from the heat of the flame.
Phosphorous flame retardants are thus able to offer specific performance properties,
depending on the required fire performance, processing conditions and mechanical
properties of the material. Certain products contain both phosphorus and chlorine, bromine
or nitrogen, thus combining the different flame retarding mechanisms of these elements.
They are widely used in standard and engineering plastics, polyurethane foams, thermosets,
back coating and textiles.
2.2.7.3 Nitrogen flame retardant
Three chemical groups can be distinguished: pure melamine, melamine derivatives, i.e. salts
with organic or inorganic acids such as boric acid, cyanuric acid, phosphoric acid or
pyro/poly-phosphoric acid, and melamine homologues such as melam, melem and melon,
the latter finding only experimental use at this stage. Nitrogen flame retardants are believed
to act by several mechanisms: In the condensed phase, melamine is transformed into cross-
linked structures which promote char formation. Ammonia is released in these reactions. In
conjunction with phosphorus, the nitrogen appears to enhance the attachment of the
phosphorus to the polymer. A mechanism in the gas phase may be the release of molecular
nitrogen which dilutes the volatile polymer decomposition products.
2.2.7.4 Intumescent coatings
Intumescent coatings are fire protection systems which are used to protect materials such
as wood or plastic from fire (prevent burning), but also to protect steel and other materials
from the high temperatures of fires (thus preventing or retarding structural damage during
fires). The coatings are made of a combination of products, applied to the surface like a
paint, which are designed to expand to form an insulating and fire resistant covering when
subject to heat.
The products involved contain a number of essential interdependent components:
 spumific compounds, which (when heated) release large quantities of non-
flammable gas (such as nitrogen, ammonia, CO2)
 a binder, which (when heated) melts to give a thick liquid, thus trapping the released
gas in bubbles and producing a thick layer of froth
 An acid source and a carbon compound. On heating, the acid source releases
phosphoric, boric, or sulphuric acid, which chars the carbon compound (mechanism
described under phosphorus flame retardants above) causing the layer of bubbles to

Page | 28
harden and producing a fire resistant barrier. Often the binder can also serve as the
carbon compound.
2.2.7.5 Mineral flame retardants
Aluminium trihydroxide (ATH) is by far the most widely used flame retardant on a tonnage
basis. It is inexpensive, but usually requires higher loadings in polymers up to more than
60%, because the flame retardant mechanism is based on the release of water which cools
and dilutes the flame zone. Magnesium hydroxide (MDH) is used in polymers which have
higher processing temperatures, because it is stable up to temperatures of around 300°C
versus ATH which decomposes around 200 °C. Other inorganic fillers like talcum or chalk
(calcium carbonate) are not flame retardants in the common sense; however, simply by
diluting the combustible polymer they reduce its flammability and fire load. Fine
precipitated ATH and MDH (< 2 µm) are used in melt compounding and extrusion of
thermoplastics like cable PVC or polyolefins for cables. For use in cable, ATH and more often
MDH are coated with organic materials to improve their compatibility with the polymer.
Coarser ground and air separated grades can be used in liquid resin compounding of
thermosets for electrical applications, seats, panels and vehicle parts.
2.2.7.6 Halogen-free Flame Retardants
Most halogen-free flame retardants have an environmentally friendly profile, which means
that they pose no harm to the environment and do not bio-accumulate in biota. In addition
they have a low (eco) toxicity profile and will eventually mineralize in nature. Due to these
characteristics, none of the halogen-free flame retardants are considered to be PBT or vPvB.
Metal phosphinates: These are well suited for glass fibre reinforced
polyamides and polyesters and are added at levels of about 20 % –
often combined with N-synergists. Key aspects are a high
phosphorus content (> 23 %), no affinity to water and a good
thermal stability (up to 320 °C) which make them compatible with
lead free soldering operations.
Inorganic Metal phosphinates are an old known chemical class recently
introduced as active FR component in different proprietary synergistic
blends. Used in different polymers, especially Polypropylene homo and
copolymer for UL 94 V2 applications at some percent loading, gives very
high GWIT on thin items. They can be used in PC, PC/ABS, PS, TPU and
some engineering polymers like PBT and PA6 thanks to his very high
phosphorus content in the range 20 to 40 %, thermal stability, and non-
blooming characteristics.
Melamine Polyphosphate (MPP) is especially suited for glass fibre
reinforced polyamide 6,6, where it is added at ca. 25 % for UL 94 V0
performance. It has a good thermal stability (ca. 300 °C). MPP is
often used as synergist in combination with phosphorus FRs.

Page | 29
Melamine cyanurate (MC) is especially suited for unfilled and mineral
filled polyamides. UL 94 V0 can be achieved with 10 to 15 % in unfilled
PA and up to 20 % for UL 94 V2 in low glass filled PA 6. MC is often
used as synergist in combination with phosphorus FRs.
Red phosphorus is a polymeric form of elemental phosphorus. It is
used mainly in glass fibre reinforced PA 6,6 at 5 to 8 % addition
level, where its high efficiency at low loading guarantee to maintain
the excellent mechanical and electrical properties of the polymer
while obtaining the highest flame proofing characteristics. Due to its
inherent colour, compounds are limited to red or black colours. In
addition, precautions against degradation have to be taken.
Aryl phosphates and phosphonates: their main use is styrenic blends
at 10 to 20 % addition level for UL 94 V0. They are often used as co-
components in FR-formulation. Their limitations are possible
plastisicing effects and a certain volatility at high processing
temperatures. Blooming can have a negative influence on electrical
properties
Magnesium hydroxide (MDH, Mg(OH)2: high filler levels of about 45 to 50 % are necessary to
reach UL 94 V0. Because of its limited temperature stability, it is mainly used in low glass
fibre PA 6.
Ammonium polyphosphate in combination with nitrogen synergists
can be used in polyolefins at addition levels of ca. 20 to 30 %.
2.2.7.7 Other Flame Retardants - Borates, & Stannates.
Boron containing compounds: A major application of borates is the use of mixtures of boric
acids and borax as flame retardants for cellulose (cotton) and of zinc borate for PVC and
other plastics like polyolefins, elastomers, polyamides, or epoxy resins. In halogen-
containing systems, zinc borate is used in conjunction with antimony oxide, while in
halogen-free systems, it is normally used in conjunction with aluminium trihydroxide,
magnesium hydroxide, or red phosphorus. In some particular applications zinc borate can be
used alone. Boron containing compounds act by stepwise release of water and formation of
a glassy coating protecting the surface.
Zinc compounds were initially developed as smoke suppressants for PVC (Zinc hydroxyl
stannate). Later it was found that they also act as flame retardants in certain plastics mainly
by promoting char formation. Zinc sulphide shows synergistic effects in PVC and can partly
substitute antimony trioxide.

Page | 30
Main flame retardants that are used by industries:-
Antimony trioxide
Chemical formula: Sb2O3
Density: 502g/cm3
Melting point: 656° C
Boiling point: 1425° C
Antimony trioxide is the organic compound with formula Sb2 O3. It is the most important
commercial compound of antimony. It is found in nature as the minerals valentinite and
senarmontite. Like most polymeric oxides, Sb2 O3 dissolves in aqueous solution with
hydrolysis.
The structure of Sb2O3 depends on the temperature of the sample. Dimeric Sb4O6 is the high
temperature (1560) gas. Sb4O6 molecules are bicyclic cages, similar to the related oxide of
phosphorus(III), phosphorus trioxide. The cage structure is retained in solid that crystallizes
in a cubic habit. The most stable form is orthorhombic, consisting of Sb-o-Sb-o chains that
are linked by oxide bridges between the Sb centers. This form is exists as in nature as the
mineral valentinite.
The main application is as flame retardant synergist in
combination with halogenated materials. The combination of halides and the antimony
being the key to the flame retardant action for polymers, helping to from less flammable
chars. Such flame retardants are found in electrical apparatus, textiles, leather, and
coatings.
Tetra bromo bisphinol A (TBBA)
Chemical formula: C15H12Br4O2
Density: 2.12g/cm 3
Melting point: 178 O C
Boiling point: 250 O C

Page | 31
Tetra bromo bisphinol A is a brominated flame retardant. The compound is a colorless solid,
although commercial samples appear yellowish. It is one of the most common flame
retardants.
TBBA is mainly used as a reactive component of polymers, meaning that it is incorporated
into the polymer back bone. It is used to prepare fire resistant polycarbonate by replacing
some bisphenol A. A lower grade of TBBPA is used to prepare epoxy resins, used in printed
circuit boards.
Deca (decabromodiphenyl ether)
Chemical formula: C12Br10O
Density: 3.64g/cm3
Melting point: 294 to 296oC
Boiling point: 425oC
Decabromodiphenyl ether is a brominated flame
retardant which belongs to the group of polybrominated diphenyl ethers.
Deca is a flame retardant which is always used in conjunction.
Antimony trioxide in polymers. Mainly in high impact polystyrene which is used in the
television industry for cabinet backs.
Alamark-275(dibutyl tin maleate)
Chemical formula: C12H20O4Sn
Molecular weight: 346.99
Melting point: 135 to 140oC
Specific gravity (water) 1.36 to 1.42
Used as condensation catalyst, stabilizers for PVC resin.
Dibutyl maleate has been found to impart both flame retardant
synergism and uv stabilization, when used in conjunction with
organo bromine flame retardant.
1, 2-Bis (2,4,6-tribromophenoxy)ethane
One of the major "novel" brominated flame retardants
(NBFRs) from various polymer materials. An environmental
pollutant. Simple aromatic halogenated organic compounds,
such as 1, 2-Bis (2, 4, 6-tribromophenoxy) ethane, are very
unreactive. Reactivity generally decreases with increased
degree of substitution of halogen for hydrogen atoms.
Materials in this group may be incompatible with strong oxidizing and reducing agents. Also,
they are incompatible with many amines, nitrides, azo/diazo compounds, alkali metals, and
epoxides.

Page | 32
CHAPTER-3
METHODOLOGY
3.1 Materials
ABSTRON AN450M (injection moulding FR grade) and ABSTRON IM118 (injection moulding,
medium flow, high impact, medium rigidity) ABS were used for this study. They were
supplied by Bhansali Engineering Polymers Limited, in the form of extruded pellets. Typical
ABS properties are summarized in below table 3.1. The manufacturer has the proprietary
right on the ratio of ABS monomer. Based on information given by the manufacturer, ABS
consists of 60% styrene, 25% acrylonitrile and 15% butadiene approximately. Types, trade
name, manufacturer and applications of materials for ABS is presented in table 3.2. Six types
of additives were used in this study. There are EBS (Ethylene bis(stearamide)), calcium
stearate, Silicon oil, TBBA(Tetra bromo bisphinol A) , ATO(Antimony trioxide), OTS(dibutyl
tin maleate) . The trade name, manufacturer and purpose of materials are stated in table
3.3 below.
Table 3.1: Typical properties of ABS (injection moulding grade)
Type Trade Name Manufacturer Applications
Heat resistant ABSTRON HR59 Bhansali Engineering
Polymers Limited
Remote Controller
Cases, Air Cleaner
Parts.
Injection Moluding ABSTRON IM11B Bhansali Engineering
Polymers Limited
Printer Parts,
Headphone Stereo
Body, Key Board.
Flame Retardant ABSTRON AN450M Bhansali Engineering
Polymers Limited
Interior Parts of
Refrigerator, Exterior
Parts of Room Air-
Conditioner.
Table 3.2: Types, trade name, manufacturer and purpose of material for ABS

Page | 33
Table 3.3: Types, trade name, manufacturer and purpose of materials for additives
Type Trade name Manufacturer Purpose
EBS HI-LUB CMS Chemical,
Indonesia.
Decreasing friction
and abrasion of the
polymer surface, and
to contribute colour
stability and polymer
degradation.
CS Calcium Stearate Sunshine organic
Pvt, Ltd. , India
It can act as an acid
scavenger or
neutralizer at
concentrations up to
1000ppm, a
lubricant and a
release agent.
Si-Oil FLUID 100 Wacker metroark
chemical Pvt. Ltd,
India
Primarily used as
lubricants.
TBBA FR-1524 ICL industrial
Products, Bromine
Compounds Ltd,
Israel
It is one of the most
common flame
retardants.
TBBA is mainly used
as a reactive
component of
polymers, meaning
that it is
incorporated into
the polymer back
bone.
ATO XN Chemico chemical
Pvt, Ltd, India
The combination of
halides and the
antimony being the
key to the flame
retardant action for
polymers, helping to
from less flammable
chars.
OTS STS 102 SV plastochem pvt
Ltd, India
Dibutyl maleate has
been found to
impart both flame
retardant synergism
and uv stabilization,
when used in
conjunction with
organo bromine
flame retardant.

Page | 34
3.2 Material Formulation
Ingredients Resin in % and additive in Phr recipe
HRG 30-33
SAN-LF 45-48
EBS(Ethylene bis(stearamide)) 0.4-0.8
CS(Calcium stearate) 0.2-0.4
Si-Oil 0.1-0.15
TBBA(Tetra bromo bisphinol A) 20-30
ATO(Antimony Trioxide) 3-7
OTS(dibutyl tin maleate) 0.2-0.6
Table 3.4: Material Formulation
3.3 Preparation of material
3.3.1 Dry blending
The correct proportion of the resin and the additives had to be weighed by using Electronic
Balance.
A Hopper Dryer Type: KET/166120, KABRA EXTRUSION TECHNIK, INDIA was used to dry the
ABS resins since ABS is a hygroscopic material which can absorb moisture up to 0.3% within
24 hours. The duration for dry blending process was 5 minutes.
3.3.2 Extrusion
The standard temperatures of the grade are set on the extruders and the attainment
of temperatures is monitored. Till attaining the temperature the functioning of the
downstream equipment’s are checked. The materials are taken from the premix silo
to the hopper of the extruder. The extruder is operated with the standard operating
guidelines. The mixed materials are extruded as per work instructions. As soon
as the materials comes out of the die holes, it goes through the water in the water
bath for quenching, passes through the air knife blower for drying, enters into the
pelletiser for cutting of the granules, passes through the double decker vibrator for
segregation of pellets as per the sizes.

Page | 35
3.3.3 Injection Moulding
Impact bars were injection moulded by using SP-80 Injection moulding machine. The
mould for injecting the test specimens is shown in Figure. The parameter of the
setting is shown in Table.
Table 3.5: Injection moulding operation condition
Figure 3.1 : Mould for Injection moulding specimen

Page | 36
CHAPTER-4
EXPERIMENTAL WORK
Flame retardants comprise a diverse group of chemicals which are widely used at relatively
high concentrations in many applications, including the manufacture of electronic
equipment, textiles, and plastic polymers and in the car industry, primarily to protect
materials against ignition and to prevent fire-related damage. More than 175 different types
of flame retardants exist, which are commonly divided into four major groups: halogenated
organic (usually brominated or chlorinated), inorganic, organophosphorus and nitrogen-
containing flame retardants. Depending on the mode of action, flame retardants can act at
any of the steps involved in the combustion process. Flame retardants are designed to
prevent the spread of fire and have thereby helped to save many lives while also
dramatically reducing the economic impact of fires.
There is need for fire resistant polymers in the construction of small, enclosed spaces such
as skyscrapers, boats, and airplane cabins. In these tight spaces, ability to escape in the
event of a fire is compromised, increasing fire risk. In fact, some studies report that about
20% of victims of airplane crashes are killed not by the crash itself but by ensuing fires. So it
is very important to test the plastic product before it reaches the market. Testing yields
basic information about a Plastic, its properties relative to another material and its quality in
reference to a standard. In this study I was conducted eight tests which are:-
 Pendulum Izod impact test
 Flexural test
 Flammability
 Heat defection temperature
 MFI (Melt Flow Index)
 Specific gravity
 Tensile strength
 Rockwell hardness
4.1 Testing and Analysis Procedure Figure 4.1 : Impact tester
4.1.1 Pendulum Impact Test
The impact test was done according to ASTM D 256A by using
Izod impact tester, pendulum type model (the maker is CEAST)
as shown in Figure. The test specimen obtained from the
injection moulding, was then notched using a notching
machine. The notching machine used is made by HEM. The
notch depth fixed at 3 ± 0.05 mm. The impact strength is
calculated by dividing the indicator reading (energy) by the
cross sectional area of the specimen. The results were
reported in kJ/m2 of notch for notched specimens. This test
was measured at room temperature (25 ± 2°C) and 50 ± 5%
relative humidity.

Page | 37
Figure 4.2: Dimension measurement for Izod type test specimen
4.1.2 Flexural test
Flexural test was carried out according to ASTM D 790. The test
procedure used is Test Method 1, Procedure A, i.e., three-point
loading utilizing center loading. Since the modulus was
determined between small initial deflections, to ensure good
accuracy, a low force load cell (100N) was used. Flexural test was
carried out a simple supported beam. The distance between the
spans was 100 mm and the strain rate (compression speed) was 5
mm/min. The flexural properties were measured at room
temperature (25 ± 2 oC) on a Universal Testing machine (make:
LLOYD instrument, Model: LRX 5K) as shown in Figure. Five
samples were tested and average values were recorded.
Figure 4.3: Flexural tester
4.1.3 Flammability test
 Test Method : UL-94
 Specimen size : 125 x 13 x 3 mm
 Conditioning : 23 ± 2ºC and 50 ± 5 R.H., 48 hrs.
 Methane gas flow : 105 ml/min. with back pressure
 Rate to burner : 10 mm water.
 Flame height : 20 ± 1 mm
 Flame calibration : 100ºC to 700ºC within 44 ± 2 sec. Figure 4.4: Flammability
Apply flame to the middle of the bottom edge for 10 sec. and
remove the burner. Measure after flame time in secs -
t1. Again apply the flame for another 10 secs. Measure after
flame time - t2 and afterglow time - t3. Check the dripping
particle ignited the cotton or not.

Page | 38
4.1.4 Heat Deflection Temperature (HDT)
Heat deflection temperature is defined as the
temperature at which a standard test bar (127 x 12.5 x 3
mm) deflects 0.25 mm. under a stated load of 1820 kPa.
This test can distinguish between those materials that
lose their rigidity over a narrow temperature range and
those that are able to sustain light at high temperature.
HDT test was carried out following ASTM D 648, with HDT
Tester 148HDD machine (Maker: Yasuda Seiki) as
illustrated in Figure 4.5. The apparatus for measuring HDT
consists of an enclose oil bath fitted with a heating
chamber and automatic heating control. A cooling system
is also incorporated. The specimens were supported on
steel supports that are 4 in. apart, with the load applied
on top of the specimen vertically and midway between
the supports. A dial indicator was used to measure
deflection. Figure 4.5: HDT
4.1.5 Melt Flow Index (MFI)
Melt flow index (MFI) of the polymer was determined according to
ASTM D1238 at 220 °C under a load of 10 kg. The equipment used
was Deven port Model: MF110. About 3 g of sample was introduced
into the barrel, at 220°C and was allowed to melt and achieve
thermal equilibrium for 5 minutes. Load of 10 kg was applied on the
melt and material was extruded through the die. The extrudates
were cut at regular interval, usually at 15 secs interval. The cut-off
extrudates were weighed and the value was converted to the unit of
g/10 min. Figure 4.6: MFI
4.1.6 Specific gravity test
Specific gravity is a measure of the ratio of mass of a given volume of material at 23°C to the
same volume of deionized water. There are two basic test procedures- Method A and
Method B. The more common being Method A, can
be used with sheet, rod, tube and molded articles.
For Method A, the specimen is weighed in air then
weighed when immersed in distilled water at 23°C
using a sinker and wire to hold the specimen
completely submerged as required. Density and
Specific Gravity are calculated.
Figure 4.7: Specific Gravity

Page | 39
4.1.7 Tensile test
Tensile strength is a measurement of the ability of a material to
withstand forces that tend to pull it apart and to determine to what
extent the material stretches before breaking. Specimens are
placed in the grips of the universal tester (Make: Instron, Model:
1011) at a specified grip separation and pulled until failure. For
ASTM D 638 the test speed is determined by the material
specification. An extensometer is used to determine elongation and
tensile modulus.
Tensile strength = Force (load)/area
Elongation = Change in length / Original length
Figure 4.8: UTM
4.1.8 Rockwell hardness test
A Rockwell hardness number is a number derived from a net increase in depth impression as
the load on an indenter is increased from a fixed minor load to a major load and then return
to minor load. Hardness test was carried out by ASTM D 785.Choose the correct scale for
the specimen under test. Rockwell hardness values are reported by a letter to indicate the
scale used and a number to indicate the reading. The Rockwell hardness scale used shall be
selected, unless otherwise noted in individual methods or specifications. Discard the first
reading after changing a ball indenter, as the indenter does not properly seat by hand
adjustment in the housing chuck. The full pressure of the major load is required to seat the
indenter shoulder into the chuck.
With the specimen in place on the anvil, turn the capstan
screw until the small pointer is at a zero position and the
large pointer is within ± 5 divisions of B 30 or the "set"
position on red scale. This adjustment applies without
shock a minor load of 10 kg, which is built into the
machine. Final adjustment of the gage to "set" is made by a
knurled ring located on some machines just below the
capstan hand wheel. If the operator should overshoot his
"set" adjustment, another trial shall be made in a different
test position of the specimen; under no circumstances
should a reading be taken when the capstan is turned
backward. Within 10 s after applying the minor load, and
immediately after the "set" position is obtained, apply the
major load by releasing the trip lever. Remove the major
load 15 (+ 1, -0) s after its application. Read the Rockwell
hardness on the red scale to the nearest full scale division
15 s after removing the major load. Record the readings.
Figure 4.9: Hardness tester

Page | 40
CHAPTER-5
RESULT AND DISCUSSION
5.1 Comparison between ABSTRON AN450M (FR) & ABSTRON IM11B
5.1.1 ABSTRON AN450M (FR grade)
Table 5.1: properties of ABSTRON AN450M (FR grade)
Tests Test condition Test method unit Typical value
Rheological Test
Melt Flow Index At 220°C/10Kg ASTM D 1238 gm/10 min 43
Mechanical tests
Izod impact,
notched 3.2mm
23±2°C ASTM D 256,
Method A
Kgfcm/cm 23
Izod impact
notched 6.4mm
23±2°C ASTM D 256,
Method A
Kgfcm/cm 19
Tensile
strength, Type I,
3.2mm at yield
50mm/min ASTM D 638 K/sq.cm 445
Flexural
strength,
6.4mm at yield
5mm/min ASTM D 790 Kg/sq.cm 570
Flexural
modulus,
6.4mm at yield
Rockwell
hardness
ASTM D 785 R-scale 100
Thermal tests
Heat distortion
temperature,
6.4mm
At 18.5
Kg/sq.cm(
annealed at
75°C/2Hr)
ASTM D 648,
Method-A
°C 87
Flame class rating
Flammability,
3.0mm
UL-94 V0
Other tests
Specific gravity ASTM D 792 1.17
Mould
shrinkage
ASTM D 955 % 0.40-0.60

Page | 41
5.1.2 ABSTRON IM11B (Normal grade)
Table 5.2: Properties of ABSTRON IM11B (Normal grade)
Tests Test condition Test method unit Typical value
Rheological Test
Melt Flow Index At 220°C/10Kg ASTM D 1238 gm/10 min 32
Mechanical tests
Izod impact,
notched 3.2mm
23±2°C ASTM D 256,
Method A
Kgfcm/cm 29
Izod impact
notched 6.4mm
23±2°C ASTM D 256,
Method A
Kgfcm/cm 23
Tensile
strength, Type I,
3.2mm at yield
50mm/min ASTM D 638 K/sq.cm 470
Flexural
strength,
6.4mm at yield
Flexural
modulus,
6.4mm at yield
Rockwell
hardness
ASTM D 785 R-scale 106
Thermal tests
Heat distortion
temperature,
6.4mm
At 18.5
Kg/sq.cm(
annealed at
85°C/2Hr)
ASTM D 648,
Method-A
°C 94
Flame class rating
Flammability,
3.2mm
UL-94 HB
Other tests
Specific gravity ASTM D 792 1.045
Mould
shrinkage
ASTM D 955 % 0.40-0.60

Page | 42
5.1.3 Table description
The ability of a material to absorb the energy of a high-speed blow without breaking is a
property of great technological importance. Izod impact test is one of the empirical methods
of measuring impact strength in current use in the plastics industry. A pendulum striker hits
the specimen horizontally at a point above the notch. After the specimen has been
fractured, the pendulum continues on its and the energy remaining is measured by the
extent of the excess swing.
In this study I have conducted numerous tests to find out the izod impact strength. I have
done five tests for each. I have noticed that in both cases (notched 3.2mm and 6.4mm) a
lowering of impact strength from 29 to 23 Kgfcm/cm.
Tensile strength (TS) is the maximum stress that a material can withstand while being
stretched or pulled before failing or breaking. Some materials will break sharply, without
plastic deformation, in what is called a brittle failure. Others, which are more ductile,
including most metals, will experience some plastic deformation and possibly necking
before fracture. Tensile strength is defined as a stress, which is measured as force per unit
area. It is expressed in newtons per square metre (N/m²).
I have done five tests for each to find out the tensile value. There is reduction in tensile
strength from 470 to 445Kg/sq.cm
The flexural properties of materials are of considerable technical importance since
deformations involving flexure are most frequent. Usually a molded article must be
designed to maintain its shape under flexure. Therefore, flexural stiffness or modulus of
flexure is a property of considerable technical importance. Flexural strength is the ability of
the material to withstand bending forces applied perpendicular to its longitudinal axis. The
stresses induced by the flexural load are a combination of compressive and tensile stresses.
In this test also I have done five tests for each ABS grade. I came to know that both flexural
strength and flexural modulus are lowering from ABSTRON IM11B to ABSTRON AN450M.
The values are 630 & 21500 and 570 & 20500 respectively.
The Rockwell test determines the hardness by measuring the depth of penetration of an
indenter under a large load compared to the penetration made by a preload. There are
different scales, denoted by a single letter, that use different loads or indenters.
I have done the test on R-scale, I got the values of ABSTRON IM11B and ABSTRON AN450M,
which are 106 and 100 respectively.

Page | 43
The quality of material extruded through a standard orifice under specified temperature and
load, measured for 10 minutes. The test load conditions of MFI measurement is normally
expressed in kilograms rather than any other units. The method is described in the similar
standards ASTM D1238. Melt flow rate is an indirect measure of molecular weight, with high
melt flow rate corresponding to low molecular weight. At the same time, melt flow rate is a
measure of the ability of the material's melt to flow under pressure. Melt flow rate is
inversely proportional to viscosity of the melt at the conditions of the test, though it should
be borne in mind that the viscosity for any such material depends on the applied force.
Ratios between two melt flow rate values for one material at different gravimetric weights
are often used as a measure for the broadness of the molecular weight distribution.
Under 220°C temperature and 10Kg load I got two values of ABSTRON IM11B and ABSTRON
AN450M, which are 32 and 43 respectively.
Heat deflection temperature is defined as the temperature at which a standard test bar
deflects a specified distance under a load of 66psi and 264psi. It is used to determine short-
term heat resistance. It distinguishes between materials that are able to sustain light loads
at high temperatures and those that lose rigidity over a narrow temperature range. The test
specimen is loaded in three-point bending in the edgewise direction. The outer fiber stress
used for testing is either 0.455 MPa or 1.82 MPa, and the temperature is increased at
2°C/min until the specimen deflects 0.25 mm.
The values for heat distortion temperature test was 94 and 87 (under 18.56Kg/sq.cm) for
ABSTRON IM11B and ABSTRON AN450M respectively.
Flammability is the ability of a substance to burn or ignite, causing fire or combustion. The
degree of difficulty required to cause the combustion of a substance is quantified through
fire testing. Thermoplastic materials are more or less easily combustible. Efforts to develop
flame retarding plastic materials have been going along with the increasing use of
thermoplastics. As a result, flame retarding formulations are available today for all
thermoplastics which strongly reduce the probability of their burning in the initiating phase
of fire. The possibility to make plastic flame retardant secures the scope of utilization for
thermoplastics and, in fact increases their range of application.
I have conducted horizontal burning (HB) for ABSTRON IM11B at 3.2mm and vertical
burning (V0) for ABSTRON AN450M at 3.0mm
Specific gravity is the ratio of the density of a substance to the density (mass of the same
unit volume) of a reference substance.
The values for specific gravity of ABSTRON IM11B and ABSTRON AN450M are 1.045 and 1.17
respectively.

Page | 44
CHAPTER-6
CONCLUSIONS AND RECOMMENDATIONS
6.1 Overall conclusion
The main objective of this project is to study the effect of flame retardancy in a flame
retardant grade. For that I have selected two ABS grade which are ABSTRON IM11B (natural)
and ABSTRON AN450M (FR-grade). And I have conducted several tests to find out the
properties of ABS. A synergistic effect in which the impact strength of the ABSTRON IM11B
(natural) is found to be higher than ABSTRON AN450M (FR-grade). The data for ABS was
obtained from this study whereas the impact strength value of ABSTRON AN450M with
increasing content of flame retardants, the impact strength of the grade is decreased.
The HDT analysis shows that the temperature at which the materials loss rigidity decrease
slightly as the loading level of flame retardant into ABS increased. The flame retardancy of
ABS is relatively poor with natural detroite the most rapidly. The polybutadiene in ABS with
the double bond structure is a highly flammable material. From the result obtained, the
effect of flame retardant on ABSTRON AN450M shows the highest increment of flame
retardancy. The most optimum formulation in terms of cost and mechanical properties is
ABSTRON AN450M. From the properties obtained, it is proposed that this material is
suitable to produce suitcase and parts of miscellaneous goods such as computer monitor,
photocopier parts, fax machine parts, and parts of camera and printer.
6.2 Recommendations
The initial work on flammability properties has given interesting results. This method
can be further investigated by developed a correlation between LOI and smoke
density (smoke production). Char determination can also be carried out by using
DTA/TGA technique to record accurately heat and mass change. Incorporation of
flame retardant will reduce the mechanical properties of the material. In order to
minimize the reduction, compatibilizer should be added to study the effect of
coupling agents in flame retarded ABS material. Investigate the effects of
compatibilizer on flame retarded ABS material. Use higher content of flame
retardant. Incorporation of different types of flame retardant (not more than 10 phr)
into ABS such as:
Iron compounds Brominated materials
FeOOH – Bayferrox yellow 3905 (Bayer) Octabromodiphenyl oxide
Fe3O4 – ferrosoferric black iron oxide 1,2 – bistribromophenoxy ethane
FeOCl – iron (III) oxychloride Poly-dibromostyrene
Iron (III0 molybdate decabromodiphenyl ether
Table 6.1: Recommended Fire retardants

Page | 45
REFERENCES
1. Adams, M. E., Buckley, D. J., Colborn, R. E., England, W. P., and Schissel, D. N. (1993).
Acrylonitrile-Butadiene-Styrene Polymers. United Kingdom: Rapra Preview Reports.
3-4.
2. Alexander H. T. (2000). Plastics Additives’ Steady Evolution. Business. 78: 21- 31.
3. Bach, H. C. and Knorr, R. S. (1989). Encyclopedia of Polymer Science and Engineering
Volume 1. John Wiley & Sons. 388-423.
4. Bair, H. E., Boyle, D. J. and Kelleher, P. G. (1980). The Effect of Light and Heat on the
Rubber Content and Impact Strength of ABS. Polymer Engineering and Science.
20(15): 995-1001.
5. Billmeyer, F. W. JR. (1984). Textbook of Polymer Science 3rd Edition. Toronto: John
Wiley& Sons. 301-345.
6. Brisimitzakis, A. C. (1994). Styrenic Resins. In Modern Plastic Magazine ed.
Encyclopedia Handbook. United States of America : McGraw-Hill, Inc. 52- 53.
7. Broutman, L. J. and Kobayashi, T. (1971). AMMRC CR 71-14, Army. Material
Mechanical Res. Ctr. Watertown, Massachussetts. In Sridharan, N. S. and Broutman,
L. J. (1982). Fracture Analysis of Acrylonitrile-Butadiene-Styrene Resins. Polymer
Engineering and Science. 22(12): 760-765.
8. Brydson, J. A. (1995). Plastics Materials Sixth Edition. Oxford : Butterworth-
Heinemann Ltd. 77.
9. Bucknall, C. B. (1977). Toughened Plastics. England: Applied Science Publishers Ltd.
90-94.
10. Bucknall, C. B. and Smith, R. R. (1965). Stress-Whitening in High-Impact Polystyrene.
Journal of Polymer. 6. 437-446.
11. Chanda. M., and Roy. S. K. (1993). Plastic Technology Handbook. New York: Marcel
Dekker, Inc. 561-566.
12. Codgell, J. F. and Hardesty, R. M. (1958). SPE Journal. 14. 25. In Norbert, M. B. ed.
(1971). Mechanical Properties of Polymers. New Jersey: Wiley Interscience. 175-222.
13. Frank, L. F. (1991). Combustibility of Plastics. New York: Van Nostrand Reinhold. 122-
179.

Page | 46
14. Freedonia Industry Study. (2002). Engineered Plastics. U.S.A: CEH Marketing
Research Report. 2-3.
15. Fried, J. R. (1995). Polymer Science and Technology. USA: Prentice Hall, Inc. 251-263.
16. GAM Report. (2000). Moulding News. World Plastic Technology 2000. 41.
17. Gao, J. G., Li, D. L., Wang, D. Y. and Yang, L. T. (2000). Rheological behaviour and
Mechanical Properties of Blends of Chlorinated Polyethylene with Poly(Acrylonitrile-
Styrene-Methyl Methacrylate). European Polymer Journal. 36: 2517-2522.
18. Glenn, B., Hilton and Cathleen, A. J. (1985). Acrylonitrile –Butadiene-Styrene. In
James, M. Margolis. ed. Engineering Thermoplastics Properties and Applications.
New York : Marcel Dekker Inc. 335-371.
19. Green, J. (1989). Flame Retardant and Smoke Suppressants. In John T. Lutz, Jr.
Thermoplastic Polymer Additives. New York: Marcel Dekker, Inc. 93-204.
20. Jenkner, H. and Köln. (1983). Flame retardants for Thermoplastics. In Gächter, R and
Müller, H. Plastics Additives Handbook. New York: Hanser Publishers. 537-540.
21. Kuryla, W. C. and Papa, A. J. ed. (1973). Flame Retardancy of Polymeric Materials
Volume 3. New York: Marcel Dekker. In Chanda. M., and Roy. S. K. (1993). Plastic
Technology Handbook. New York: Marcel Dekker, Inc. 61.
22. Landrock, A. H. (1983). Handbook of Plastics Flammability and Combustion
Toxicology. New Jerseyy: Noyes Publications. 18-26, 36-41.
23. Mitsuru, Y, Shinichi, S and Yasuji, K. (1983). Comparison of Poly(styrene,
polystyrene/Acrylonitrile), High Impact Polystyrene and
Poly(acrylonitrile/Butadiene/Styrene) with Respect to Tensile and Impact Properties.
Journal of Applied Polymer Science. 28: 2209-2216.
24. Modern Plastic Magazine. ed. (1994). Encyclopedia Handbook. USA: McGraw- Hill,
Inc. 5-6.
25. Moh Ching Oliver Chang, Benny, D., Trishna Ray-chaudhuri, Liqing L. Sun, and Russell
P. Wong. (1997). Acrylonitrile-Butadiene-Styrene (ABS) Polymers. In Olagoke Olabisi.
Handbook of Thermoplastics. New York: Marcel Dekker, Inc. 135-160.
26. Molinaro, H. ed. (1999a). Lounging Aboard Coextruded Polymers. Society of Plastic
Engineers. 55(7): 6.

Page | 47
27. Moore, E. R. ed. (1989). Encyclopedia of Polymer Science and Engineering. John
Wiley & Sons. 319-321.
28. Nelson, G. L. (1995). Fire and Polymers: An Overview. In Fire and Polymers II.
Materials and Tests for Hazard Prevention. Washington: American Chemical Society.
1-25, 65-75.
29. Owen, S. R. and Harper, J. F. (1998). Mechanical, Microscopical and Fire Retardant
Studies of ABS Polymers. Polymer Degradation and Stability. 64: 449-455.
30. Troitzsch, J. (1980). International Plastics Flammability Handbook. New York: Hanser
Publisher. 17-61.
31. Uhlmann, J. G. Oelberg, J. D., Sikkema, K. D. and Nelb, R. G. (1993). Effect of Flame
Retardant Structure and Properties on ABS Performance. Plastic Compounding. 3:
38-46.
32. U.S. Environmental Protection Agency (2005). Environmental Profiles of Chemical
Flame retardant Alternatives for Low-Density Polyurethane Foam (Report). EPA 742-
R-05-002A. Retrieved 4 April 2013.
33. "Market Study Flame Retardants 3rd ed.". Ceresana Research. Retrieved 2015-02-03.
34. Market Study Flame Retardants 2nd ed., Ceresana, 07/11
35. Hollingbery, LA; Hull TR (2010). "The Thermal Decomposition of Huntite and
Hydromagnesite". Thermochimica Acta 509 (1–2): 1–11.
doi:10.1016/j.tca.2010.06.012.
36. Hollingbery, LA; Hull TR (2010). "The Fire Retardant Behaviour of Huntite and
Hydromagnesite - A Review". Polymer Degradation and Stability 95 (12): 2213–2225.
doi:10.1016/j.polymdegradstab.2010.08.019.
37. Hollingbery, LA; Hull TR (2012). "The Fire Retardant Effects of Huntite in Natural
Mixtures with Hydromagnesite". Polymer Degradation and Stability 97 (4): 504–512.
38. Hollingbery, LA; Hull TR (2012). "The Thermal Decomposition of Natural Mixtures of
Huntite and Hydromagnesite". Thermochimica Acta 528: 45–52.
doi:10.1016/j.tca.2011.11.002.
39. Hull, TR; Witkowski A; Hollingbery LA (2011). "Fire Retardant Action of Mineral
Fillers". Polymer Degradation and Stability 96 (8): 1462–1469.

Page | 48
40. van der Veen, I; de Boer, J (2012). "Phosphorus flame retardants: Properties,
production, environmental occurrence, toxicity and analysis". Chemosphere 88 (10):
1119–1153. doi:10.1016/j.chemosphere.2012.03.067. PMID 22537891.
41. Weil, ED; Levchik, SV (2009). Flame Retardants for Plastics and Textiles: Practical
Applications. Munich: Carl Hanser Verlag. p. 97. ISBN 978-1-56990-454-1.
42. Shaw, S.; Blum, A.; Weber, R.; Kannan, K.; Rich, D.; Lucas, D.; Koshland, C.; Dobraca,
D.; Hanson, S.; Birnbaum, L. (2010). "Halogenated flame retardants: do the fire
safety benefits justify the risks?". Reviews on Environmental Health 25 (4): 261–305.
doi:10.1515/REVEH.2010.25.4.261. PMID 21268442.
43. California Department of Consumer Affairs, Bureau of Home Furnishings (2000).
Technical Bulletin 117: Requirements, test procedure and apparatus for testing the
flame retardance of resilient filling (PDF) (Report). p. 1-8.
44. "Notice of Proposed New Flammability Standards for Upholstered Furniture/Articles
Exempt from Flammability Standards". Department of Consumer Affairs, Bureau of
Electronic and Appliance Repair, Home Furnishings and Thermal Insulation.
45. "Calif. law change sparks debate over use of flame retardants in furniture". PBS
Newshour. January 1, 2014. Retrieved November 1, 2014.
46. "Low VOC Cal TB 117 Using Bio-Renewable Technologies - Rowlands, J. Polyurethane
Foam Association Conference St Petersburg, Florida USA.- May 2013".
47. "Future-Proof Natural Foams for the USDA BioPreferred Program - Rowlands, J.
Utech Conference and Exhibition, Charlotte USA. June 4th and 5th 2014".
48. Guillame, E.; Chivas, C.; Sainrat, E. (2000). Regulatory issues and flame retardant
usage in upholstered furniture in Europe (PDF) (Report). Fire Behaviour Division. p.
38-48.
49. Greenstreet Berman Ltd., "A statistical report to investigate the effectiveness of the
Furniture and Furnishings (Fire) (Safety) Regulations 1988", (December 2009). The
study was carried out for the UK Department of Business and Innovation skills (BIS).
http://www.bis.gov.uk/files/file54041.pdf
50. Babrauskas, V.; Harris, R.; Gann, R.; Levin, B.; Lee, B.; Peacock, R.; Paabo, M.; Twilley,
W.; Yoklavich, M.; Clark, H. (1988). NBS Special Publication 749: Fire hazard
comparison of fire-retarded and non-fire-retarded products (Report). National
Bureau of Standards, Center for Fire Research, Fire Measurement and Research
Division. p. 1-86.

Page | 49
APPENDIX
The global market for flame retardant chemicals was worth $4.1 billion in 2008 and a
projected $4.3 billion in 2009. It reached $6.1 billion by 2014, for a compound annual
growth rate (CAGR) of 7.0%. The global flame retardant chemicals industry used 3.2 billion
pounds of materials in 2008. This is increased to 3.4 billion pounds in 2009, and 4.3 billion
pounds in 2014, for a CAGR of 5.0%. Studies have shown that a burning room containing
flame retardant products releases 75% less heat and 33% fewer toxic gases than a room that
lacks the products.
In 2006 Pentabromodiphenyl ether and Octabromodiphenyl ether were voluntarily
withdrawn by the last major manufacturer of these chemicals (Great Lakes Chemical
Corporation, now part of Chemtura) and regulated heavily in the US by the Environmental
Protection Agency (EPA), thus ensuring that there would be no new major use of these
chemicals.
In 2012, all brominated diphenyl ethers have been voluntarily withdrawn by the main flame
retardant manufacturers and also placed under EPA regulatory control for phase-out and
banning of import or use in the US. These rules effectively eliminate the use of these flame
retardant additives in any new product sold in the US, but this flame retardant may be
present in many existing products that already contains that flame retardant. HBCD, used
mostly for expanded polystyrene foam insulation, has also been selected for phase out in
the USA and Canada.
In one year, two widely used classes of flame retardants have been voluntarily withdrawn by
the manufacturers and put under regulatory ban. This has had two major effects, one
political, and one technical. It has given companies the impetus to develop viable safer
commercial alternatives and it has emboldened non-governmental organizations (NGO) to
push for further bans.
Figure A1: Global consumption of Flame retardants

EFFECT OF FLAME RETARDANT ADDITIVES IN FLAME RETARDANT GRADE OF ABS

EFFECT OF FLAME RETARDANT ADDITIVES IN FLAME RETARDANT GRADE OF ABS

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Similar to EFFECT OF FLAME RETARDANT ADDITIVES IN FLAME RETARDANT GRADE OF ABS

Similar to EFFECT OF FLAME RETARDANT ADDITIVES IN FLAME RETARDANT GRADE OF ABS (20)

More from Arjun K Gopi

More from Arjun K Gopi (20)

Recently uploaded

Recently uploaded (20)

EFFECT OF FLAME RETARDANT ADDITIVES IN FLAME RETARDANT GRADE OF ABS