Crosslinking reaction in the cationic polymerization of 1, 3-pentadiene

The eationic polymerization of 1, 3-pentadiene (PD) initiated by A1C13 inn-hexane was carried out. Effects of arenes, alkyl halides and ethers on the gel formation resulting from crosslinking reaction were investigated. The crosslinking was reduced by various arenes through a chain transfer mechanism. Alkyl halides such asrert-butyl chloride and allyl chloride could complex with AlCl3 to generate an initiating system giving rise to a gel-free polymerization, while benzyl chloride reduced the formation of gel by chain transfer. Ethers exerted two effects on the polymerization system: giving a complex initiating system with AlCl3 to produce a relatively high molecular weight polymer, or reducing crosslinking by lowering activity of carbocations.

The cationic polymerization of 1,3-pentadiene （PD） initiated by AlCl3 in n-hexane was carried out. Effects of arenes, alkyl halides and ethers on the gel formation resulting from crosslinking reaction were investigated. The erosslinking was reduced by various arenes through a chain transfer mechanism. Alkyl halides such as tert-butyl chloride and allyl chloride could complex with AlCl3 to generate an initiating system giving rise to a gel-free polymerization, while benzyl chloride reduced the formation of gel by chain transfer. Ethers exerted two effects on the polymerization system: giving a complex initiating system with AlCl3 to produce a relatively high molecular weight polymer, or reducing crosslinking by lowering activity of carbocations.