反应详情

A thermoplastic resin composition was produced in the same manner as in Example 40, except that in place of MS-PP-2 and MS-EPM-2, a co-grafting product of the starting polypropylene for MS-PP-2 and the starting ethylene-propylene copolymer rubber for MS-EPM-2 was used. In a Hensachel mixer, 100 parts by weight of a blend of powder of the starting polypropylene for MS-PP-2 and pellets of the starting ethylene-propylene copolymer rubber for MS-EPM-2 in the ratio of 55:23 was uniformly mixed with 1.5 parts by weight of maleic anhydride, 0.5 part by weight of styrene, 0.6 part by weight of the propylene homopolymer containing as free-radical initiator 8% by weight of 1,3-bis(t-butylperoxyisopropyl)benzene (Sanperox®-TY1.3, mfd. by Sanken Kako Co., Ltd.) supported thereon, and 0.1 part by weight of 1010 (mfd. by Ciba-Geigy Ltd.) as stabilizer. The resulting mixture was melt-kneaded by means of a TEX 44 SS-30BW-2V type twin screw extruder mfd. by JAPAN STEEL WORKS, LTD., at a temperature of 220° C. for an average residence time of 1.5 minutes to obtain a (maleic anhydride-styrene)-co-grafted polypropylene/ethylene-propylene copolymer rubber having an amount of maleic anhydride added of 0.24% by weight, an amount of styrene added of 0.23% by weight and a melt flow rate of 15 g/10 min. This co-grafting product is hereinafter abbreviated as MS-(PP-2/EPM-2).