PURPOSE: To obtain a flame-retardant resin composition which comprises a styrenic resin, red phosphorus, a blowing agent of high temperature decomposition type and a silane coupling agent, thus is useful in household appliances, OA appliances and automotive part items because it causes no generation of corrosive or toxic gas and has good balance between its fluidity and shock resistance.
CONSTITUTION: This resin composition comprises (A) 100 pts.wt. of a styrenic resin such as HI polystyrene, ABS resin, (B) 10 to 55, preferably 15 to 40 pts.wt. of red phosphorus or a phosphorus flame retardant, (C) 0.2 to 10 pts.wt. preferably 1 to 5 pts.wt. of a high-temperature decomposition type foaming agent, preferably decomposing above 200°C, for example, azodicarbon-amide, N,N'- dinitrosopentamethylenetetramine, 5,5'-bis-1H-tetrazole manganese salt and (D) 0.2 to 5 pts.wt., preferably 0.5 to 2 pts.wt. of a silane coupling agent (preferably having vinyl or methacryl groups, for example, vinyl trimethoxysilane, vinyl triethoxysilane, γ-methacryloxy propyl methoxy silane.
HIRATA MOTOYUKI
TAJIMA KOICHI
