IONIC LIQUIDS AS CATALYSTS FOR THE IMINE BASE/ISOCYANATE-MEDIATED (IBI) RADICAL POLYMERIZATION: MECHANISTIC STUDIES AND POLYMERIZATION KINETICS CONTROL

摘要

Room temperature Ionic Liquids (ILs) have received high interest in academia within the last decades due to their use as catalysts or co-reactants in various organic and inorganic syntheses as well as in polymer and material science. Based on the inert nature of the Ionic Liquids, in most of the reactions ILs undergo no measurable conversion and, hence, become attractive even for industry. In especially, systems that require solely catalytic IL amounts are potential candidates for further investigations on the industrial sector. Subject of this chapter is to show the use of Ionic Liquids as catalysts for the recently reported imine base/isocyanate (IBI) mediated radical polymerization of methyl methacrylate (MMA). Investigations on this quaternary reactive system allowed both an enhancement of the polymerization properties of the IBI mixtures and the gain of deeper insights to the reaction mechanism of this novel radical polymerization type. Typical IBI mixtures initiate the radical polymerization at slightly elevated temperatures or by adding high molar amounts of the imine base and the iscyanate compared to the monomer equivalent; the addition of Ionic Liquid traces to the polymerization mixture gives polymerization of the monomer even at room temperature for all IBI mixtures and an enormous increase in the brutto reaction rate.