To provide a propylene based block copolymer that, when used as a molding material, exhibits an extremely good stiffness-impact resistance balance and has good heat. resistance and excellent moldability, and therefore, in molding, good appearance is revealed. That is, the invention provides a propylene based block copolymer obtained through a preceding stage step of producing a propylene polymer component (PP) and a subsequent stage step of producing a propylene-ethylene copolymer component (EP) using a metallocene catalyst, wherein the block copolymer satisfies specific requisites.
提供一种
丙烯基嵌段共聚物,在用作模塑材料时,该嵌段共聚物具有极佳的刚度-抗冲击平衡性,并且具有良好的耐热性和优异的可模塑性,因此在模塑过程中可显示出良好的外观。也就是说,本发明提供了一种
丙烯基嵌段共聚物,该嵌段共聚物通过使用茂
金属催化剂生产
丙烯聚合物组分(PP)的前一阶段步骤和生产
丙烯-
乙烯共聚物组分(EP)的后一阶段步骤获得,其中嵌段共聚物满足特定的要求。