The preparation of polypropylene alloy by 2-stage heterophase catalytic copolymerization of ethylene, propylene and 1-butene on spheric Ziegler-Natta catalyst had been studied.

• 采用球形Z-N催化剂,使用乙烯、丙烯和1-丁烯作为共聚单体,分步聚合催化合成了三元多相共聚聚丙烯。