机构地区: 中山大学化学与化学工程学院高分子研究所
出 处: 《高等学校化学学报》 1994年第3期454-460,共7页
摘 要: 研究了新型高活性乙烯气相聚合催化剂TiCl_4/MgCl_2/ZnCl_2/SiCl_4/醇/Al(i-Bu)_3体系中钛和醇组分含量对聚合反应和产物颗粒形态的影响。测定了乙烯气相聚合反应动力学曲线,确定了聚合动力学方程。用SEM、DSC、WAXD、 ̄(13)CNMR对催化剂及聚合物的形态、结构和性能进行了分析和表征。 The gaseous phase homo-and copolymerization of ethylene has been studied in the presence of TiCl_4/MgCl_2/ZnCl2/SiCl_4/alcohol/Al(i-Bu )_3 highly active catalyst which was prepared by comilling-reaction procedure. It was found that the catalytic efficiency and bulk density of PE decreased with increase in content of titanium compound.The added i-C_3H_7OH raises the catalytic performance and improves the morphology as well as particle distribution of the PE with a optimum dosage of i-C_3H_7OH/MgCl_2=1.0-1.5. The kinetics of gaseous phase ethylene polymerization has been investigated. The polymerization rate equation in good agreement with experimental evidence is expressed as:v_t-v_s=(v_0-vs)e ̄(-βt).The morphologies of the catalyst before and after prepolymerization as well as PE and LLDPE were examined by SEM.The structures and properties of the PE with LLDPE were studied by WAXD,DSC and ̄(13)C NMR.