SOLUTION COPOLYMERIZATION OF D-LACTOSE-O-(P-VINYLBENZYL)-HYDROXIME WITH ACRYLONITRILE

Copolymerization of D-lactose-O-(p-vinylbenzyl)-hydroxime (LVH), a new vinyl monomer, with acrylonitrile (AN) was performed in DMSO with AIB N as the initiator. The conversion of LVH is much faster than that of AN and reaches 100% in 2 h. The reactivity ratios of LVH and AN, as de termined by the extended Kelen-Tudos method, are 1.0975 and 0.0554, re spectively. Increasing the proportion of LVH in the monomer mixture si gnificantly increases the LVH content in the copolymer. The conversion of monomers and the AN content in the copolymer rise gradually with i ncreasing reaction time and initiator concentration. The number averag e molecular weights of the copolymers are independent of the monomer f eed ratios. The LVH-co-AN copolymers exhibit lower glass transition te mperatures than PLVH homopolymer. The presence of small amounts of LVH in the copolymer chain reduce the cyclization of nitrile groups in AN segments of the copolymer. Complete disappearance of nitrile cyclizat ion is observed when the contents of LVH reaches and exceeds 16.9%. (C ) 1998 Elsevier Science Ltd. All rights reserved.