Flame Retardants for Plastics and Composite Materials

Flame retardants for plastics and WPCs are completely different from those of wood materials. Wood is typically impregnated with solutions of flame retardants, commonly salts, such as monoanunonium and diammonium phosphate, ammonium sulfate, zinc chloride, sodium tetraborate, boric acid, and guanylurea phosphate. In 

PVC-based composites, nnlike many other thermoplastic-based composites, are natural fire-resistant materials (see Chapter 2). Their FSl is in the range of 25-60 (Table 14.4), in Class A-B range. However, PVC also often employs flame retardants, mainly ATH, for fnrther decrease in its flammability. 

Generally, all groups of plastics utilize flame retardants when needed for their performance and specific application. Below is a short chart showing flame retardants that are used the most in the respective plastics. 

ATH (almost ten times more than the second FR, chlorinated compounds) 

ATH (twice as much as compared with the second FR, organophosphorus componnds, nonhalogenated) Brominated compounds and antimony oxides 

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