机构地区: 中国石油化工集团公司北京化工研究院
出 处: 《石油化工》 2005年第8期734-738,共5页
摘 要: 以S iO2和M gC l2为复合载体,制备了T iC l4/S iO2-M gC l2复合载体催化剂,并将该催化体系用于丙烯聚合,研究了催化剂及聚合物的形态及孔特征,考察了助催化剂浓度、外给电子体浓度、氢气加入量及聚合温度等对催化剂性能的影响。实验结果表明,该催化剂的粒径分布窄,具有较大的孔体积和孔径,制得的聚丙烯也具有孔隙率高、孔径大等特点;铝钛摩尔比为600、铝硅摩尔比为20时,该催化剂具有获得较高的催化活性,同时聚丙烯具有较高的等规度;该催化剂具有较好的氢调敏感性,在较高的熔体流动指数下聚丙烯仍具有较高的等规度;随聚合温度的升高,该催化剂的催化活性以及聚丙烯的等规度均增加,聚丙烯的熔体流动指数则先减小后增加。 A novel TiCl4/SiO2 -MgCl2 supported catalyst was prepared and bulk polymerization of propylene on this catalyst was investigated. Morphologies and pore characteristics of the catalyst and polymer were investigated by means of SEM, N2 adsorption and mercury injection method. Effects of n (A1) : n ( Ti), n (A1) :n ( Si), H2 dosage and polymerization temperature on catalyst performance were discussed. Catalyst featured by its narrow particle diameter distribution, big pore volume and pore size. The produced polypropylene also had high porosity and good pore structure. High catalyst activity and PP isotacticity could be obtained when n (A1) :n (Ti) = 600 and n (A1) : n (Si) = 20. Catalyst showed good sensitivity to hydrogen. To be noticed, polypropylene with high melt index was still high in isotacticity. With increasing of polymerization temperature, catalytic activity and PP isotacticity increased, while melt index of PP firstly increased and then decreased.
关 键 词: 二氧化硅 氯化镁 复合载体 催化剂 聚合 聚丙烯
领 域: [化学工程]