A continuous process for preparation of highly rigid propylene-ethylene block copolymers
申请人:CHISSO CORPORATION
公开号:EP0739917A1
公开(公告)日:1996-10-30
A continuous process for preparation of propylene-ethylene block copolymer suitable for moldings with high rigidity and high impact resistance are provided, which process is a continuous process for preparation of highly rigid propylene-ethylene block copolymers, wherein propylene and ethylene are polymerized in the specified 2 steps with use of a catalyst system comprising (A) a solid catalyst component containing Ti, Mg, halogen and polyvalent carboxylic ester, (B) an organic aluminium compound, as well as (C) an organic silicon compound expressed by the general formula R4xR5ySi(OR6)z (wherein, x+y+z=4), and wherein the ratio between the maximum value and the minimum value of MFR(1)) is0.1 ≦ Log(MFR(h)/MFR(l)) ≦ 1, and the ratio between the average MFR(i) and MFR(ii) in the subsequent polymerization procedure (II) containing ethylene in a relatively large amount which is carried out by adding the glycol type compound is3 ≦ Log(MFR(i)/MFR(ii)) ≦ 7.
The product having less fish eye and high impact resistant value was obtained from the copolymer according to the invention.
提供了一种制备丙烯-乙烯嵌段共聚物的连续工艺,该工艺适用于具有高刚性和高抗冲击性的模塑件,该工艺是制备高刚性丙烯-乙烯嵌段共聚物的连续工艺,其中丙烯和乙烯在指定的 2 个步骤中聚合,使用的催化剂体系包括(A)固体催化剂组分,其中含有钛、镁、卤素和多价羧酸酯;(B)有机铝化合物;以及(C)由通式 R4xR5ySi(OR6) 表示的有机硅化合物、镁、卤素和多价羧酸酯的固体催化剂组分,(B) 有机铝化合物,以及(C) 由通式 R4xR5ySi(OR6)z 表示的有机硅化合物(其中,x+y+z=4),其中 MFR(1) 的最大值和最小值之间的比率为 0.1 ≦ Log(MFR(h)/MFR(l)) ≦ 1,通过添加乙二醇型化合物进行的含有相对大量乙烯的后续聚合程序(II)中的平均 MFR(i) 和 MFR(ii) 之间的比率为3 ≦ Log(MFR(i)/MFR(ii)) ≦ 7。
根据本发明的共聚物可获得鱼眼少、抗冲击值高的产品。