申请人:Hoechst Aktiengesellschaft
公开号:US05132381A1
公开(公告)日:1992-07-21
A syndiotactic polyolefin is obtained in a high yield by polymerization or copolymerization of an olefin of the formula R.sup.a --CH.dbd.CH--R.sup.b in the presence of a catalyst consisting of a metallocene of the formula I ##STR1## and an aluminoxane. This polyolefin has a very high syndiotactic index. At a low polymerization temperature, a polyolefin having a low average molecular weight and narrow molecular weight distribution is obtained, and at a high polymerization temperature a polymer having a high average molecular weight and a wide molecular weight distribution is obtained. Shaped articles produced from the polymers are distinguished by a high transparency, flexibility, tear strength and excellent surface gloss.
通过在存在铝氧烷催化剂的情况下聚合或共聚式聚合公式为R.sup.a --CH.dbd.CH--R.sup.b的烯烃,可高产得到一个高度对称的聚烯烃。该聚烯烃具有非常高的对称指数。在低聚合温度下,得到平均分子量低且分子量分布窄的聚烯烃,而在高聚合温度下,得到平均分子量高且分子量分布宽的聚合物。由这些聚合物制成的成型制品具有高透明度、柔韧性、撕裂强度和优良的表面光泽。