| 摘要 |
PROBLEM TO BE SOLVED: To obtain a red-phosphorus-containing flame-retardant resin composition which has improved mechanical strengths, flame retardance, moldability, and coatability and whose degradation in strengths due to the addition of red phosphorus is prevented by compounding a rubber-reinforced styrene resin with a phenol resin and a red phosphorus flame retardant. SOLUTION: This composition is prepared by compounding 100 pts.wt. rubber- reinforced styrene resin (A) with 1-30 pts.wt. sum of a phenol resin (B) and a red phosphorus flame retardant (C) in a ratio of C/B of 1-20. Ingredient A contains a graft polymer formed by grafting a vinyl compound onto a rubbery polymer which has a wt. average particle size of 200-1,500 nm and of which at least 20 wt.% is accounted for by rubber particles having particle sizes of 320-2,000 nm. The surface graft covering ratio defined by the formula of the vinyl compound grafted onto the rubber particles is 80% or higher; and the average thickness of the vinyl compound grafted onto the particle surface is 5-25 nm. In the formula, S is the surface area of the rubbery polymer; and (s) is the surface area of the vinyl compound covering the surface of the rubbery polymer. |
