Synthesis and quaternization of nitroxide-terminated poly(4-vinylpyridine-co-acrylonitrile) macroinitiators and related diblock copolymers

摘要

Nitroxide-terminated 4VP AN copolymers have been synthesized at 125 oC using an alkoxyamine (MAMA-SG1) as a unimolecular initiator. Their compositions were compared with those published for the conventional radical 4VP-AN copolymerization. To verify the initiation potential of the copolymers containing nitroxyl end groups, they were employed in chain extension with styrene (S). Both the prepared statistic copolymer macroinitiators and related diblock copolymers, poly(4VP-co-AN) and poly(4VP-co-AN)-block-poly(S), respectively, were quaternized with methyl iodide in N,N-dimethylformamide or methanol at ambient temperature. The size-exclusion chromatography and NMR were used for the characterization of the polymers; the completeness of the quaternization was checked by the IR spectrometry.