采用邻苯二甲酸酯类为内给电子体,制备了MgCl2/SiO2复合载体负载的Ziegler-Natta催化剂,考察了不同聚合条件、MgCl2和SiO2质量比、内给电子体结构对复合载体催化剂催化1-丁烯聚合的影响.结果表明,在三乙基铝(AlEt3)为助催化剂、铝钛物质的量比为200、聚合压力为0.10 M Pa、聚合温度为30℃ 、氢气4 m L、聚合时间为2 h时,催化剂活性较高,而外给电子体甲基环己基二甲氧基硅烷(CHMMS)加入聚合体系后,催化剂活性下降,但聚合产物等规度提高,当CHMMS与铝的物质的量比为0.033时,聚合产物的等规度最高为95.4%,复合载体催化剂中SiO 2比例增加,活性下降,邻苯二甲酸二异丁酯作为内给电子体更有利于聚丁烯-1等规度的提高.%MgCl2/SiO2 composites-supported Ziegler-Natta catalyst was prepared by using phthalate as internal electron donor . The effects of different polymerization conditions , the mass ratio of MgCl2 and SiO2 , and the structure of internal electron donor on the polymerization of 1-butene catalyzed by the supported catalyst were investigated . The results indicate that the maxi-mum activity of the catalyst for 1-butene polymerization is obtained under the following optimal conditions:triethyl aluminum as cocatalyst ,mole ratio of Al to Ti of 200 ,0 .10 MPa polymerization pressure ,30 ℃ polymerization temperature ,4mL hydrogen and 2 h reaction time .Although the ad-dition of cyclohexyl methyl dimethoxysilane (CHMMS ) into the polymerization system decreased the activity of the catalyst , the isotacticity of the polymer products increased . When the molar ra-tio of CHMMS and Al was 0 .033 ,the isotacticity of the polymer was 95 .4% .The ratio of SiO2 in the supported catalyst increased , the activity decreased , and diisobutyl phthalate as the internal electron donor was more favorable for the isotacticity of polybutene-1 .
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