Industrial Adaptability of the Ziegler-Natta Catalyst-Friendly Synthesis of Long-Chain-Branched Polypropylene Based on ω-Alkenylmethyldichlorosilane-Assisted Propylene Polymerization

omega-Alkenylmethyldichlorosilane-assisted propylene polymerization for the synthesis of long-chain-branched polypropylene (LCB-PP) was applied in a liquid bulk polymerization process to verify its industrial adaptability. The select omega-alkenylmethyldichlorosilane, 5-hexenylmethyldichlorosilane (hex-DCS), was introduced into propylene bulk polymerization conducted with a commercial Ziegler-Natta catalyst in the presence of hydrogen (H-2). A general validity is revealed. LCB-PPs of varied LCB degrees and tunable chain characteristics (homopolymer, random copolymer, and different molecular weights) were achieved using several hundred parts per million of hex-DCS with a largely stable catalyst performance. The LCB-PPs revealed correspondent melt properties including increased melt strength, enhanced shear-thinning behavior, and significant strain hardening effect as well as increased melt crystallization temperatures resulting from nucleation by the LCB structure.

Automated summary

The study applied omega-Alkenylmethyldichlorosilane-assisted propylene polymerization for the synthesis of long-chain-branched polypropylene (LCB-PP) in a liquid bulk polymerization process to verify its industrial adaptability. By introducing small amounts of hex-DCS, LCB-PPs with varied chain characteristics were successfully achieved, exhibiting corresponding melt properties.