FLAME RETARDANT POLYMER COMPOSITION

摘要

A flame retardant polymer composition consists of a) 20 - 60 percent by weight of a thermoplastic and/or cross-linked or cross-linkable elastomer and b) as a flame retardant agent 40 - 80 percent by weight either of an aluminium hydroxide with the material values - specific surface according to BET 3 - 5 mg2/g - mean grain size d50 1.0 - 1.5 .mu.m - residual moisture 0.1 - 0.4 % - oil absorption 19 - 23% - water absorption 0.4 - 0.6 ml/g or of an aluminium hydroxide with the material values - specific surface according to BET 5 - 8 m2/g - mean grain size d50 0.8 - 1.3 .mu.m residual moisture 0.1 - 0.6 % - oil absorption 21 - 25 % - water absorption 0.6 - 0.8 ml/g. A process of producing the flame retardant agent is characterised in that a filter-moist aluminium hydroxide obtained by precipitation and filtration with a mean grain size of 0.8 to 1.5 .mu.m is subjected to mill drying in a turbulent hot air stream in such a way that, while the grain distribution is largely retained, the BET surface is increased by at least 20 %.