Flame Retardants

1. Higher Technological Institute-10TH of Ramadan City
Department of Chemical Engineering
FLAME RETARDANTS (FRs)
Presented by students
AbdAl-Rhman Magdy Abdullah Youssef
20160517
AbdAl-Rhman Ali Basheer
20160476
Amr Ahmed Saeed
20160629
Mohamed Mostafa Khalil
20140924
Mohamed Soliman Hassan
20141318
Supervisors
Prof. Maher Gamal Soliman
Professor of Chemical Engineering
Department of Chemical Engineering
Higher Technological Institute-10th of Ramadan City
Eng. Aya Abdelfattah
Assistant Teacher
Department of Chemical Engineering
Higher Technological Institute-10th of Ramadan City
April | 2019

2. Contents
oIntroduction.
oFire Triangle.
oTypes of Flame Retardants.
oFlammability Testing.
oPolymer Combustion Mechanism.
oFlame Retardance Mechanism.
oApplications.
oFlame Retardants Suppliers.
oReferences.

3. Introduction
❑Flame retardants refer to a variety of substances that are added to combustible
materials to prevent fires from starting or to slow the spread of fire and provide
additional escape time.
❑It refers to a function, not a family of chemicals. A variety of different chemistries, with
different properties and molecular structures, act as flame retardants and these
chemicals are often combined for effectiveness.
❑It has different types such as; Additives & Reactives & Intumescents.
❑ Several Methods used by FRs to prevent flame propagation.
❑Applications; Connectors, Communication Cables, Thermal Insolation, Kitchen Applications

4. Fire Triangle
❑For combustion to take place three components are necessary and these
form the fire triangle, removing any one of the components will prevent or
extinguish a fire, these components are:
✓Fuel.
✓Air.
✓Ignition source

6. Flame Retardants Types
Additive
Filler Semi
plasticizer Plasticizer
Reactive Intumescents
Non-Flame
Retardant
systems

8. Burning Behavior
oLimiting Oxygen Index (LOI)
oUnderwriters Laboratory (UL94)
oHorizontal Burning Test (94HB)
oVertical Burning Test (94V)

9. Limiting Oxygen Index (LOI)
o LOI is a measure of the percentage of oxygen that has to be present to support
combustion of the plastic
o The higher the LOI the lower the flammability.
o In the LOI test, a candle like sample is supported in a vertical glass column and
a slow stream of oxygen/nitrogen mix is fed into the glass column.
o The sample is ignited with a flame and burns downward into unheated
material.
o The oxygen/nitrogen ratio can be varied and the test records the minimum
concentration of oxygen (as a percentage) that will just support combustion.
Material LOI
PMMA 17
PP 17
PE 17
PS 18
PVC 45
PC 26
PTFE >95

10. Underwriters Laboratory (UL94)
o UL testing is a method of classifying a material’s tendency to either extinguish or spread a flame once
it has been ignited.
o The testing involves applying a flame to a sample in various orientations and assessing the response of
the material after the flame is removed.
o Materials that burn slowly or self extinguish and do not drip flaming material will rank highest

11. Horizontal Burning Test (94HB)
o This is the easiest test to pass.
o The test involves applying a flame to one end of a horizontal bar of the plastic for
30 seconds or until the flame front reaches the specified mark.
o If burning continues then the time taken to reach the second mark is measured.
If burning stops then the time of burning and the damaged length are measured.
o A material will be classified 94HB if the time taken to reach the second mark is
greater than the specified minimum or if burning stops before the second mark.
HB Test

12. Vertical Burning Test (94V)
o This is a more hard test than the HB test because the specimen is tested in the vertical
orientation.
o At which the material burning at the lower end of the sample preheats the material in
the upper areas of the specimen.
VB Test

14. Stages of Polymer Combustion Process

16. Major Factors in Reducing the Flammability of Materials
oElimination of volatile fuel.
oQuenching the chain reactions in the flame.
oProduction of a thermal barrier.

17. I. Heat Absorbing
❑ Heat absorbing mean using flame heat in some reaction to reduce or prevent
combustibility
❑ Metal hydrates; such as aluminum tri-hydrate (ATH) Or magnesium
Hydroxide are typically suitable for this purpose.
❑ This type of compounds simply absorb heat of flame for evaporating water in
its structure.
Methods of Flame Retardance

18. Methods of Flame Retardance (Cont.)
II. Flame Quenching
❑ Flame quenching mean stopping the chain reaction of flame propagation.
❑ Halogenated compounds; such as boric acid are typically suitable materials for this purpose.
❑ They act in the flame zone by forming a blanket of halogen vapor that interferes with the propagation of
the flame by interrupting the generation of highly reactive free radicals
❑ Synergists; such as antimony trioxide and antimony pentoxide, are used for enhancing flame quenchers
performance.

19. Brominated Epoxy

20. Methods of Flame Retardance (Cont.)
III. Char Forming
❑ Char forming mean stopping flame propagation by production a charred layer.
❑ Phosphorus Compounds; such as phosphate ester are typically suitable materials for this purpose.
❑ It provide protective layer reduce the energy of fire that material objected to it.
Chemical structure of
Phosphate esters

21. Fig. (): Difference of using and non-using char layer

23. Electrical Parts & Electronics
(a)Paper machine (b) Connectors & Switches (d) Junctions boxes(c) T.V & Computers monitors

24. Cables & Appliances
(a) Usual wires (c) Automotive Cables (d) Electrical Appliances(b) Marine Cables

25. Building & Construction
(a) Water tubes and its fittings (b) Construction tools (c) Thermal Insulations

26. & AutomotiveTransportation
(a) Upholstery For Cars Seating (b) Thermal Insulation For Storage Box In Trucks

28. Harwick Chemical
Dover Chemical
Ferro Corporation
Great Lakes Chemical

29. References
❑CRC Press LLC, Robert O. Ebewele, "Polymer Science and Technology“, 2000,
CH.9.
❑JOHN WILEY & SONS, INC, Charles A. Harper, Edward M. Petrie, "PLASTICS
MATERIALSAND PROCESSES A Concise Encyclopedia”, 2003, Page 199, 200, 201,
and 202.

30. Thanks For Attention
Any Questions ???