A polypropylene molding composition having syndiotactic polymer chains is obtained in a high yield by the copolymerization of propylene with ethylene or a 1-olefin of the formula R.sup.a --CH.dbd.CH--R.sup.b in the presence of a catalyst comprising a metallocene of the formula I ##STR1## in which M.sup.1 is titanium, zirconium, hafnium, vanadium, riobium or tantalum, and an aluminoxane. This molding composition has a very high molecular weight, a very narrow molecular-weight distribution and very high syndiotaxy. Shaped articles produced from the molding composition are distinguished by high transparency, flexibility, bear strength and excellent surface luster.
通过
丙烯与
乙烯或式R.sup.a --CH.dbd.CH--R.sup.b的1-烯共聚合,在
咪唑烷配合物催化剂的存在下,与铝烷氧化物反应,可以获得含有顺反型聚合物链的聚
丙烯模压组合物,且收率高。该模压组合物具有非常高的分子量、非常窄的分子量分布和非常高的顺反型。由该模压组合物制成的成形品具有高透明度、柔韧性、承载力和优异的表面光泽。