Aspects of free radical polymerization of styrene and n-Butylmethacrylate in imidazolium tosylates

A series of 1-alkyl-3-methylimidazolium tosylates was explored as new solvents for the free radical polymerization of n-butylmethacrylate and styrene. The use of these ionic liquids results in high yields and high molecular weights of the polymers, often even exceeding the molecular weights achieved in bulk polymerization. The obtained molecular weights and their distributions are sensitive to the structure of the ionic liquids, namely to substituents of the imidazolium ring. The broad and bimodal molecular weight distributions of the polystyrene made in the 1-alkyl-3-methylimidazolium tosylates is caused by a heterophase polymerization.