申请人:Yamazaki Hiroyuki
公开号:US20050038196A1
公开(公告)日:2005-02-17
A styrene resin composition is provided which has a high molecular weight enabling a molded product obtained therefrom to have satisfactory strength, has a high melt mass-flow rate, high melt tension, and hence excellent moldability, and is less apt to gel during production, and a process for producing such a styrene resin composition. The styrene resin composition comprises a linear polystyrene having a weight average molecular weight of 200,000 to 350,000 and a multibranched polystyrene having a weight average molecular weight of 1,000,000 to 10,000,000, has an average molecular weight of 250,000 to 700,000, and a melt mass-flow rate (MFR) and melt tension (MT) which satisfy the following formulas (1) and (2) respectively:
MFR
≧45×exp(−0.1×
Mw
×10
−4
) (1)
MT
≧0.07
Mw
×10
−4
+1.8 (2).
本发明提供了一种苯乙烯树脂组合物,它具有高分子量,使由此获得的模塑产品具有令人满意的强度,具有高熔体质量流动速率和高熔体张力,因而具有优异的模塑性,并且在生产过程中不易凝胶化。苯乙烯树脂组合物包括重量平均分子量为 200,000 至 350,000 的线型聚苯乙烯和重量平均分子量为 1,000,000 至 10,000,000 的多支链聚苯乙烯(平均分子量为 250,000 至 700,000),以及分别满足以下公式 (1) 和 (2) 的熔体质量流动速率 (MFR) 和熔体张力 (MT):
MFR
≧45×exp(-0.1× Mw
Mw
×10
-4
) (1)
MT
≧0.07
Mw
×10
-4
+1.8 (2).