Flame retardants (FR)are chemical compounds added with an objective to inhibit/retard the ignition/burning of the plastic. To prevent combustion, it becomes necessary to design a thermally stable polymer that has a lesser probability of decomposing into combustible gases under heat stress.
To increase the fire resistance of plastic products, people often use some compounds such as:
Mineral compounds such as aluminum and magnesium hydroxide can be used as flame retardants. This type of additive decomposes when subjected to high temperatures. This process removes heat from the plastic and cools the material. This flame retardant is usually additive and consists of compounds antimony oxide, zinc oxide…
The most common flame retardant additives for plastics are flame retardants Bromine – A halogen compound. Chlorine and bromine compounds undergo thermal decomposition releasing hydrogen chloride and hydrogen bromide. These react with H and OH radicals in a flame to produce chlorine and bromine radicals. Since halogen radicals are less reactive than H or OH radicals, they slow down the oxidation reactions of the flame.
Halogenated flame retardants are low cost and suitable for many polymers. However, due to its toxicity to humans, animals and the environment, it has been banned.
Phosphorus flame retardants – including phosphate compounds – esters, are compounds that, when burned, form phosphoric acid, forming a thick glassy carbon layer. This prevented pyrolysis and prevented the fire. This flame retardant is often used for porous materials, with large oxygen contact area, flammable such as polyurethane foam materials (mattresses), carpets, interior decoration products, indoor rubber products, etc.
Most flame retardants for plastics are incorporated to improve their overall effectiveness. For example, bromine compounds are often used in combination with antimony trioxide. This combination acts as a catalyst to accelerate the release of bromine and chlorine radicals during phase radical quenching.