Synthesis of vinyl‐terminated isotactic poly(propylene) using the coupling reaction between Zn‐terminated polymer and allyl halides

Propene was polymerized with the TiCl 3 /Al(C 2 H 5 ) 2 Cl catalyst system using Zn(C 2 H 5 ) 2 as a chain transfer reagent. The resulting Zn‐terminated poly(propylene) (PP) was then brought into contact with allyl halides (chloride, bromide and iodide) in the presence of N ‐methylimidazole to obtain vinyl‐terminated PP. Allyl bromide gave the highest conversion among these allyl halides. When the coupling reaction was conducted with allyl bromide at 40°C for 24 h, the conversion to the terminal vinyl groups was over 90% for atactic PP and approximately 60% for isotactic PP. The Zn‐polymer bonds of both atactic and isotactic PP were almost quantitatively converted into terminal vinyl groups at 130°C for 3 h.