Controlled Cationic Polymerization of -Methylstyrene in Ionic Liquid and Its Mechanism.

Ionic liquid (IL) as a green solvent is entirely composed of ions; thus, it may be more than a simple solvent for ionic polymerization. Here, the cationic polymerization of -methylstyrene (-MeSt) initiated by 1-chloro-1-(4-methylphenyl)-ethane (-MeStCl)/tin tetrachloride (SnCl) was systematically studied in 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([Bmim][NTf]) IL at -25 °C. The results show that IL did not participate in cationic polymerization, but its ionic environment and high polarity were favorable for the polarization of initiator and monomer and facilitate the controllability.