文献类型：期刊文献

中文题名：双(水杨醛亚胺)镍配合物催化乙烯-甲基丙烯酸甲酯共聚

英文题名：Copolymerization of Ethylene and Methyl Methacrylate by Bis-(salicylaldiminato)Nickel(Ⅱ)Complexes

作者：居卫[1];于栋萍[1];徐晨斐[1];韩亦钦[1];高宜健[1];李冬亚[1];张丹枫[1]

机构：[1]华东理工大学材料科学与工程学院,上海市先进聚合物材料重点实验室,上海200237

年份：2018

卷号：44

期号：3

起止页码：340

中文期刊名：华东理工大学学报(自然科学版)

外文期刊名：Journal of East China University of Science and Technology

收录：CSTPCD;;Scopus;北大核心:【北大核心2017】；CSCD:【CSCD_E2017_2018】；

基金：上海市重点学科和重点实验室项目(WD1014050-4)

语种：中文

中文关键词：水杨醛亚胺配体;镍配合物;乙烯;甲基丙烯酸甲酯;共聚

外文关键词：salicylaldiminato ligand;nickel complex;ethylene;methyl methacrylate;copolymerization

摘要：研究了3个在苯胺基邻位含有不同位阻效应的双(水杨醛亚胺)镍配合物C1~C3的合成及其结构的分析与表征。在助催化剂甲基铝氧烷(MAO)作用下,以C3为主催化剂,考察了Al与Ni物质的量之比(n_(Al)/n_(Ni))、催化剂用量、反应温度、压力、甲基丙烯酸甲酯(MMA)浓度、时间等对乙烯与甲基丙烯酸甲酯共聚的影响,得到最佳聚合条件为:n_(Al)/n_(Ni)为150,温度25℃,压力2MPa,反应时间2h。在此条件下评价了C1、C2和C3催化剂结构对聚合反应的影响,发现在苯胺基邻位的取代基位阻较小时,催化活性较好,但所得聚合物分子量较低,并对共聚物结构进行了^(1)H-NMR、^(13)C-NMR、FT-IR等分析和表征。
Three bis-(salicylaldiminato)nickel(Ⅱ)complexes with different steric hindrances on the adjacent position of aniline group,[O-(3,5-I_(2))C_(6)H_(3)-σ-C(H)N-2,6-C_(6)H_(3)(Me)_(2)]_(2)Ni(C1),[O-(3,5-I2)C_(6)H_(3)-o-C(H)-N-2,6-C_(6)H_(3)(Et)_(2)]_(2)Ni(C_(2))and[O-(3,5-I_(2))C_(6)H_(3)-o-C(H)-N-2,6-C_(6)H_(3)(i-Pr)_(2)]_(2)Ni(C_(3)),were successfully synthesized based on the reaction of Ni(CH_(3)COO)_(2)·4 H_(2)O with ligands L1—L3,HO-(3,5-I_(2))C_(6)H_(2)-o-C(H)N-2,6-C_(6)H_(3)(Me)_(2)(L1),HO-(3,5-I_(2))C_(6)H_(2)-o-C(H)N-2,6-C_(6)H_(3)(Et)_(2)(L2)and HO-(3,5-I_(2))C_(6)H_(2)-o-C(H)N-2,6-C_(6)H_(3)(i-Pr)_(2)(L3).The ligands were characterized by^(1)H-NMR and FT-IR,and the formed complexes were characterized by^(1)H-NMR,FT-IR,element analysis(EA)and mass spectrometry(MS).The complexes were applied for copolymerization of ethylene and methyl methacrylate(MMA)in the presence of methylaluminoxane(MAO).The effects of different polymerization factors,such as Al、Ni molar ratio(n_(Al)/n_(Ni)),catalyst dosage,polymerization reaction temperature and ethylene pressure,the concentration of MMA and polymerization reaction time were investigated systematically.The optimum polymerization conditions were as follows:n_(Al)/n_(Ni)150,25℃,ethylene pressure of 2 MPa and 2 hpolymerization.With the increase of nAl/nNi,the catalyst activity first increased and then decreased.The more catalyst dosage uses,the higher molecule mass was obtained.The activity increased with the increasing of polymerization pressure.The increases of polymerization time led to an increase followed by a decrease of catalyst activity.The complexes C1—C3 were evaluated for the copolymerization under the optimum polymerization conditions.The complex C1 with small substituents on the adjacent position of aniline group displayed higher catalytic activity of 12.2 kg/(mol·h),but lower molecular mass of 5.97×10^(5).While C2 and C3 with bulky substituents on the adjacent position of aniline group showed low catalytic activity,6.8 kg/(mol·h)and C35.4 kg/(mol·h)respectively,and high molecular mass with 8.06×10^(5)for C2 and 9.85×10^(5)for C3.The microstructures of the obtained polymers were characterized by^(1)H-NMR,^(13)C-NMR and FT-IR spectra,demonstrating that the polymers were the copolymers of ethylene and MMA.