Precision Control in Radical Polymerization.-Control of Molecular Weight, Stereochemistry, and Monomer Sequence.

Abstract

This review article describes precision control of molecular weight, stereochemistry, and monomer sequence in radical polymerization. For molecular weight control, metal-catalyzed living radical polymerization, which is originated from metal-catalyzed Kharasch addition reaction, has been developed by designing the catalysts and has become applicable for a wide variety of vinyl monomers including methacrylates, acrylates, styrenes, acrylamides, vinyl acetate, etc. While the control of stereochemistry cannot be achieved by these metal catalysts, the stereochemical control based on the interaction of solvents or added Lewis acids has been combined with various living radical polymerizations for the simultaneous control of molecular weight and tacticity . A possibility of monomer sequence control has now been suggested by developing metal-catalyzed radical addition reaction to metal-catalyzed radical polyaddition of designed monomers for sequence-regulated vinyl polymers.