摘要
制备了SiCl4、PPh3促进的MgCl2 -SiO2 -ZnCl2 为载体 ,TiCl4/Ni(acac) 2 为主催化剂的A、B型乙烯聚合高效催化剂。研究了SiCl4、PPh3对乙烯气相聚合的影响 ,发现SiCl4能大幅度提高催化效率 ,PPh3使催化效率出现峰值。用DSC、IR、1 3CNMR对聚合产物进行结构性能的分析和表征。结果表明 ,TiCl4/Ni(acac) 2 组成的复合催化剂较单一Ti系催化剂的聚合产物熔点、结晶度、密度、相对分子质量明显降低。添加PPh3的B型催化剂获得了支化度为 3～ 5的支化聚乙烯 ,表明B型催化剂具有一定的低聚和原位共聚功能。
High efficiency supported ethylene polymerization catalysts of TiCl 4 -Ni(acac) 2/MgCl 2 SiO 2 ZnCl 2/AlR 3 promoted with SiCl 4(A) and PPh 3(B) were prepared.The effect of SiCl 4 and PPh 3 on gasphase polymerization of ethylene were studied.It is found that SiCl 4 and PPh 3 can enhance catalyst efficiency of ethylene polymerization.The structure and properties of polymerized products wrer characterized by DSC,IR and 13 C NMR.The results indicate that melting point,crystillinity,density and moleculer weight of polyethylene from Ti-Ni catalysts are lower than single Ti catalyst,and branching polyethylene can be obtained with B catalyst.Thus the B catalyst has the function of carrying out oligomerization and in situ copolymerization. [
出处
《石油化工》
CAS
CSCD
北大核心
2001年第6期448-452,共5页
Petrochemical Technology
基金
国家自然科学基金! ( 2 98740 3 9)
广东省自然科学基金!( 980 3 19)资助项目
