Anderson W Curtis, Long Brian K
Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States.
ACS Macro Lett. 2016 Sep 20;5(9):1029-1033. doi: 10.1021/acsmacrolett.6b00528. Epub 2016 Aug 16.
The ability to precisely modulate polymer architecture and composition is a long-standing goal within the field of polymer synthesis. Herein, we demonstrate that redox-active olefin polymerization catalysts may be used to predictably tailor polyolefin comonomer incorporation levels for the copolymerization of ethylene and higher α-olefins. This ability is facilitated via the utilization of a redox-active olefin polymerization catalyst that once reduced via addition of a chemical reductant results in a notable drop in α-olefin incorporation. We attribute this behavior to the reduced catalyst's increased electron density and its concomitant decreased rate of α-olefin consumption. These results are supported by investigations into propylene and 1-hexene homopolymerizations as well as detailed GPC, DSC, GC, and NMR analyses.
精确调控聚合物结构和组成的能力是聚合物合成领域长期以来的目标。在此，我们证明氧化还原活性烯烃聚合催化剂可用于可预测地调整乙烯与高级α-烯烃共聚时聚烯烃共聚单体的掺入水平。通过使用氧化还原活性烯烃聚合催化剂促进了这种能力，该催化剂一旦通过添加化学还原剂而被还原，α-烯烃的掺入量就会显著下降。我们将这种行为归因于还原态催化剂增加的电子密度及其随之降低的α-烯烃消耗速率。对丙烯和1-己烯均聚反应的研究以及详细的凝胶渗透色谱（GPC）、差示扫描量热法（DSC）、气相色谱（GC）和核磁共振（NMR）分析支持了这些结果。
