Block and graft copolymers of 2-oxazolines

This paper describes our recent developments of block and graft copolymers prepared by the cationic ringopening polymerization of 2-oxazolines. First, the mechanistic aspects of polymerization are mentioned, in which terms of "electrophilic and nucleophilic polymerizations" are proposed. Then, preparations and properties of poly(N-acylethylenimine) chains from 2-oxazoline monomers are described. They are (i) AB and BAB type block copolymers of 2-oxazolines for nonionic polymer surfactants, (ii) poly[(N-acetylethylenimine)-b-(oxyethylene)] for anti-electrostatic agents, (iii) cellulose diacetate having poly(N-acylethylenimine) graft chain for "compatibilizer" with commodity polymers, and (iv) polyethylene/vinyl acetate copolymer having poly(N-acylethylenimine) graft chain for blood-compatible polymeric materials.