文献类型：期刊文献

英文题名：Influence of Modified Ziegler-Natta Catalyst on the Entanglement Behavior and Properties of Ultrahigh-Molecular-Weight Polyethylene (UHMWPE)

作者：Zhou, Jian[1];Zhang, Xian[1];Zhao, Shicheng[1];Zhang, Zhenfei[2];Ye, Chunlin[1,2];Xin, Zhong[1]

机构：[1]East China Univ Sci & Technol, Dept Prod Engn, Shanghai Key Lab Multiphase Mat Chem Engn, Shanghai 200237, Peoples R China;[2]Shanghai Res Inst Chem Ind, Shanghai Key Lab Catalysis Technol Polyolefins, State Key Lab Polyolefins & Catalysis, Shanghai 200062, Peoples R China

年份：2022

卷号：61

期号：48

起止页码：17512

外文期刊名：INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH

收录：;EI(收录号：20225013232060);WOS:【SCI-EXPANDED(收录号:WOS:000891351900001)】；

基金：ACKNOWLEDGMENTS This work was financially supported by National Natural Science Foundation of China (Grant No. 22178108) .

语种：英文

外文关键词：Catalyst activity - Chlorine compounds - Crystallization - Ethylene - Magnesium compounds - Oligomers - Quantum entanglement - Ultrahigh molecular weight polyethylenes

摘要：Different dealcoholizing methods and polyhedral oligomeric silsesquioxanes (POSS) were utilized for the modification of Ziegler-Natta catalysts. Their effects on the properties of the catalysts and the synthesized ultrahigh-molecular-weight poly-ethylene (UHMWPE) were thoroughly studied. It was found that physical dealcoholization of the magnesium chloride-ethanol adducts increased the specific surface area (SSA) of the catalysts more effectively than chemical dealcoholization, expanding the contact area between active centers and ethylene. Thus, better catalytic activity was induced. The sufficient distance between growing chains is the key point in the entanglement degree of UHMWPE. With the load of TiCl4, physical dealcoholized catalysts always provide greater spacing between growing chains, decreasing the potential of segment tangling, and that matches the less-entangled state of the synthesized UHMWPE determined by the initial storage modulus by a rotary rheometer. The modification of the catalysts by polyhedral oligomeric silsesquioxanes (POSS) was also studied, and it was discovered that POSS shows little effect on catalytic activity. However, POSS-modified catalysts limited the active centers to a closer range. Coupled with the strong interaction between UHMWPE and POSS particles, UHMWPE with a higher entanglement state were produced. The crystallization behavior and mechanical properties of the obtained UHMWPE were also studied.