Shu Dongxu, Mouat Aidan R, Stephenson Casey J, Invergo Anna M, Delferro Massimiliano, Marks Tobin J
Department of Chemistry, Northwestern University, Evanston, Illinois 60208-3113, United States.
ACS Macro Lett. 2015 Nov 17;4(11):1297-1301. doi: 10.1021/acsmacrolett.5b00781. Epub 2015 Nov 6.
An unsymmetrical bimetallic catalyst, (/), having a CF-functionalized phenoxyiminato Ni(II) center, which produces linear high- polyolefin () joined to an adjacent SO-functionalized phenoxyiminato Ni(II) center, which produces highly branched low- polyolefin (), was synthesized and fully characterized. In ethylene homopolymerizations, (/) affords monomodal ( = 1.7), highly, long-chain branched (69 branches/1000 C) polyethylenes with = 24 kg/mol. In contrast, bimetallic () and () produce high- (25 kg/mol) exclusively methyl-branched (40 branches/1000 C) and low- (4.5 kg/mol) highly branched (105 branches/1000 C) polyethylenes, respectively, while tandem monometallic () + () catalyst mixtures yield a bimodal polyolefin mixture ( = 6.4).
合成并全面表征了一种不对称双金属催化剂（/），其具有一个CF官能化苯氧基亚氨基镍（II）中心，可生成与相邻的SO官能化苯氧基亚氨基镍（II）中心相连的线性高聚烯烃（），该中心可生成高度支化的低聚烯烃（）。在乙烯均聚反应中，（/）可提供单峰（= 1.7）、高度长链支化（69个支链/1000个C）的聚乙烯，其 = 24 kg/mol。相比之下，双金属（）和（）分别生成高（25 kg/mol）的仅含甲基支化（40个支链/1000个C）的聚乙烯和低（4.5 kg/mol）的高度支化（105个支链/1000个C）的聚乙烯，而串联单金属（）+（）催化剂混合物则产生双峰聚烯烃混合物（= 6.4）。
