吡啶脒基镍配合物/MAO催化降冰片烯聚合研究

Study on the polymerization of norbornene catalyzed by pyridyl nickel complex/MAO

吡啶脒基镍配合物在助催化剂甲基铝氧烷(MAO)作用下催化降冰片烯聚合。考察了催化剂结构中电子效应与位阻效应对聚合反应的影响,研究表明具有吸电子取代基的催化剂能提高催化活性,而吡啶环邻位上引入甲基取代则能同时提高催化活性和聚降冰片烯的分子量。所制备的聚降冰片烯的分子量分布受聚合温度影响,总体呈现分子量分布随温度升高而增大的趋势。聚合物的红外和核磁分析表明,聚合反应机理为乙烯基加成聚合方式。

Catalytic polymerization of norbornene catalyzed by pyridyl nickel complex in the presence of cocatalyst MAO.This paper examines the electronic and steric effect of catalyst structure on polymerization reaction. The results show that the catalyst with electron withdrawing substituent can increase catalytic activity,the catalytic activity and the molecular weight of norbornene can be improved by introducing methyl substitution on the vicinal ring of pyridine.The molecular weight distribution of the prepared poly （norbornene） is affected by the polymerization temperature, and the overall molecular weight distribution increases with the increase of temperature.The IR and NMR analysis of the polymer shows that the polymerization mechanism is vinyl addition polymerization.