Flame-retardant resin composition

摘要

The invention provides a flame-retardant thermoplastic resin composition compounded with a flame-retardant powder which, in addition to the excellent dispersibility in resins and excellent flame retardancy imparted to the resin, can reduce the amount of low molecular weight siloxanes emitted from the resin to 10 ppm or smaller, along with a flame-retardant resin composition by compounding with this flame-retardant powder. This flame-retardant powder is prepared by treating the surface of an inorganic flame-retardant powder under pressurization with an organopolysiloxane represented by the average structural formula given below and having a mass-average molecular weight of 100,000 to 3,500,000, wherein said organopolysiloxane contains not more than 2,000 ppm of low molecular weight siloxanes having from 2 to 10 silicon atoms per molecule, as determined by extraction with acetone and wherein the amount of said organopolysiloxane is 0.1 to 30 mass % relative to the mass of the inorganic flame-retardant powder: (in formula (1), each R¹ is a substituent independently selected from C₁ to C₁₀ monovalent hydrocarbon groups and hydroxyl group and n is a number that provides the organopolysiloxane with a mass-average molecular weight of 100,000 to 3,500,000).