| abstract |
This flame-retardant polyorganosiloxane includes (A) a straight-chain polyorganosiloxane having two or more alkenyl groups in one molecule and whose viscosity (25°C) is 10,000 to 1,000,000 mPa·s; (B) 30 to 80 mass% of a resinoid polyorganosiloxane which includes Q unit and has 1.5 or more alkenyl groups on average, and in which a molar ratio of alkoxy groups to alkyl groups is 0.030 or less; (C) an amount of a polyorganohydrogensiloxane, whose average degree of polymerization is 10 or more, and in which a Si-H content is 5.0 mmol/g or more, in which Si-H/(a total of alkenyl groups) is 1.0 to 3.0 mol; and (D) a hydrosilylation reaction catalyst. A flame-retardant polyorganosiloxane composition capable of reducing an amount of a platinum-based metal compound is provided. |