均相金属茂催化剂烯烃聚合的研究──Ⅱ．乙烯－己烯、乙烯－丙烯共聚的研究

HOMOGENEOUS METALLOCENE CATALYST FOR POLYMERIZATION Ⅱ. Study on Ethylene/1-hexene and Ethylene/propylene Copolymerization

研究了不同单体配比下，均相金属茂催化剂Ｃｐ２ＺｒＣｌ２／ＭＡＯ和Ｅｔ（Ｉｎｄ）２ＺｒＣｌ２／ＭＡＯ对乙烯－己烯、乙烯－丙烯的共聚性能，对共聚物性能进行了测试讨论。利用１３ＣＮＭＲ计算了乙丙共聚物的链段组成及竞聚率，发现竞聚率积γＥ·γＰ随己丙共聚的乙烯／丙烯单体配比而变化，从γＥ·γＰ＜１（嵌段共聚物）变向γＥ·γＰ＞１（交替共聚物）。选择适当的乙烯／丙烯配比可获得无规共聚物（γＥ·γＰ＝１）。

Copoiymerization of ethylene/1-hexene as well as ethylene/propylene with the homogeneous metallocene catalysts CP2ZrC12/MAO and Et(Ind),ZrCl2/MAO were studied. The properties ofthe copolymers were discussed and the structures of the copolymers were analyzed by 13C NMR. Thecomposition of the ethylene/propylene copolymers and the comonomer reactivity ratios were calculated. Itwas found that γE·γP changed with the ratio of ethylene and propylene in the ethylene/propylene copolymerization from γE·γP<1 (alternating copolymer) to γE·γP>1 (block copolymer). The random copolymers (γE·γP= 1) can be obtained by choosing the proper ratio of ethylene and propylene.