SYNTHESIS AND PROPERTIES OF HOMOPOLYMER AND COPOLYMERS OBTAINED FROM 1-OCTADECENE WITH ZIRCONOCENE CATALYSTS  

作　　者：Raul Quijada Juan L.Guevara Rene Rojas Franco M.Rabagliati 

机构地区：[1]Departamento de Ingenieria Quimica,Facultad de Ciencias Fisicasy Matematicas,Universidad de Chile,Casilla 2777,Santiago,Chile [2]Departamento Ciencias Quimicas,Facultad Quimicay Biologia,Universidad de Santiago de Chile,Casilla 40,Santiago,Chile

出　　处：《Chinese Journal of Polymer Science》2000年第3期249-254,共6页高分子科学(英文版)

基　　金：The authors wish to acknowledge the financial support of CONICYT(Projects:FONDECYT 2980060 and FONDEF 1025),Witco and Boulder Scientific Company for the supply of raw materials.

摘　　要：Studies related to the behavior of different metallocene catalysts for the homopolymerization of 1-octadecene andits copolymerization with ethylene will be presented.The metallocenes:rac-Et(Ind)_(2)ZrCl_(2),rac-Me_(2)Si(Ind)_(2)ZrCl_(2)andPh_(2)C(Flu)(Cp)ZrCl_(2)were chosen for the homopolymerization study.They show important differences in catalytic activity athigh temperatures(≥70℃),with rac-Et(Ind)_(2)ZrCl_(2)showing the highest activity.At lower temperatures(≤30℃)thedifferences are negligible.For the copolymerization of ethylene with 1-octadecene only the catalysts rac-Et(Ind)_(2)ZrCl_(2)andrac-Me_(2)Si(Ind)_(2)ZrCl_(2)were studied.The results show that their catalytic activity is just like that for the homopolymerizationof 1-octadecene,with higher activity for the metallocene with the Et-bridged catalyst.^(13)C-NMR analysis shows that thecomposition of the copolymerization products depends on the catalytic systems.Copolymers obtained with rac-Me_(2)Si(Ind)_(2)ZrCl_(2)have greater comonomer incorporation.Thermal analysis shows that poly-1-octadecene synthesized withthe catalyst rac-Et(Ind)_(2)ZrCl_(2)is very dependent on the polymerization temperature.The homopolymer obtained at 70℃presents two endothermal peaks at 41℃and 53℃,as compared with the one obtained at 30℃which presents one wider peakwith a maximum at 67℃.For the catalyst rac-Me_(2)Si(Ind)_(2)ZrCl_(2)this trend is not observed.The type of metallocene and thereaction time do not significantly change the intrinsic viscosity,but the polymerization temperature changes it drastically,giving higher values at lower temperature.Viscosity measurements on the copolymers show that an increase of comonomerconcentration in the feed reduces the molecular weight of the copolymer,and it was also found that for homopolymer,themolecular weight is independent of the catalytic systems.

关 键 词：HOMOPOLYMERIZATION COPOLYMERIZATION METALLOCENE Catalytic activity Poly-l-octadecene 

分 类 号：TQ317[化学工程—高聚物工业]