Highly tunable catalyst supports for single-site ethylene polymerization

Abstract

© 2015 American Chemical Society. A new class of tunable crystalline solid supports for metal complexes has been synthesized and used for ethylene polymerization. We developed a family of high surface area, highly dispersible layered double hydroxides (AMO-LDHs) which, on treatment with alkyl aluminum activators, are able to support metallocene and nonmetallocene complexes to make active catalyst systems for the slurry polymerization of ethylene. We show that the chemical composition of the AMO-LDH support can dramatically affect catalyst activity, polymer morphology, and polymer microstructure. A Zr K-edge EXAFS study of these active catalysts has enabled us to observe a metallocene-derived single-center catalytic species in close proximity to the support.