BLOCK AND GRAFT-COPOLYMERS OF 2-OXAZOLINES

The cationic ring-opening polymerization of 2-oxazolines is known to b e initiated by alkyl halides, Lewis acids and esters of strong acids. The polymerization proceeds by a living mechanism. Numerous block and graft copolymers have already been described. Recently it was found th at chloroformates (R-O-CO-Cl) are also useful initiators. The mechanis m of the initiation and propagation is discussed. This type of initiat ors allows the synthesis of different novel two-block and three-block copolymers, star-shape polymers, and a graft copolymer with a polyviny lacetate backbone.