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FLAME RETARDANTS
Flame retardants in an evolving regulatory & geopolitical landscape
Cameron Day of William Blythe explores the flame retardant market and trends shaping the future of the industry
Flame retardants( FRs) are a key component in many plastic items you encounter in daily life. Electronic devices, furniture, engine components, workwear and electric cables all contain chemical additives that inhibit ignition, provide self-extinguishing properties and slow down flame spread. The global market for these additives is estimated at $ 7-8 billion / year, with 85 % used in plastics and the remainder in textiles, rubber and wood. 1
Despite improvements in global fire safety standards, there has been a steady rise in fire-related deaths since 2018 across the US, Europe and China. On average between 2017-2021 there were seven fire deaths, 37 injuries and 800 fires / million population. 2 In the US alone, the reported cost of property losses to fire was $ 23 billion from 1.39 million fires in 2023.3 The Geneva Association, bringing together nearly 100 insurance companies worldwide, estimated that the cost of fire in 2017 was 1 % of GDP worldwide.
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Emerging technologies also pose new challenges for FRs. The batteries used to power electric vehicles( EV) have high energy densities and contain very flammable components, an explosive combination in the presence of an ignition source. As such, EV materials are subject to stringent FR requirements, including a minimum escape time in case of thermal runaway. Growing demand for 5G communications, wearable electronics and an increase in data centres for AI technology will all have their own unique FR challenges.
FRs in action
FRs act to decrease the flammability of a material and slow down the spread of the flame. This is achieved by a combination of chemical and physical
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Figure 1- Global consumption of FR additives by volume & examples of common commercial additives in each class
Source: Flame Retardants Online
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processes that occur in the gas and condensed phase.
In the gas phase, FR degradation products act as scavengers of the reactive OH · and H · radicals that cause fire generation. This limits chain radical propagation and reduces fire spread. FRs can also release noncombustible gases like nitrogen and water vapour, diluting the fire gas and quenching the flame in the case of water.
In the condensed phase, endothermic degradation of the FR absorbs heat generated by the burning material, taking energy away from the system. A char or protective intumescent layer can also form on the surface of the burning material, either through catalytic cross-linking mechanisms or via FR degradation
78 SPECIALITY CHEMICALS MAGAZINE ESTABLISHED 1981