摘要
采用反应法，将ＮｉＣｌ_２与ＴｉＣｌ_４负载于复合载体ＭｇＣｌ_２－ＳＯｆ_２上，制得新型双过渡金属催化体系ＴｉＣｌ_４－ＮｉＣｌ_２／ＭｇＣｌ_２－ＳｉＯ_２／Ａｌ（ｉ－Ｂｕ）_３．该催化剂用于乙烯气相聚合，当ｘ（Ｎｉ）为１２．５％时，催化剂效率最高，聚合动力学属衰减型．催化剂因含有镍化合物具有齐聚及原位共聚性能，得到的聚乙烯具有支化度为３．６～７．２支化数／１０００Ｃ的中密度聚乙烯，且产物相对分子质量增大。
A new binary transition-metal catalyst system TiCl_4 - NiCl_2/MgCl_2-SiO_2/AlR_3 was pared by precipitating reactions and was used for the gas phase homopolymerization of ethylene. The kinetics curves of gas phase polymerization showed a decline mode. It was found that both the catalystic efficiency and polymerization reaction rate have an optimum values when Ni content is 12.5%. The structures and properties of polymerization products were chararterized by FTIR and DSC.The branching degree of the polymerization products is between 3. 6 to 7. 2 branches/1000 C and the density is in the range of 0.940 to 0.948 g/cm^3.
出处
《中山大学学报（自然科学版）》
CAS
CSCD
北大核心
2000年第2期37-40,共4页
Acta Scientiarum Naturalium Universitatis Sunyatseni
基金
国家自然科学基金
燕山石化研究院联合资助项目!(29874039)
广东省自然科学基金资助项目!(980319)
关键词
气相聚合
氯化镍
催化剂
活性中心
gas phase polymerization
NiC1_2
catalyst
active centre
