Abstract
Copolymerization of styrene with 2.5 mol% of bis(4-vinylbenzyl)disulfide (1) under radical suspension polymerization conditions gave an insoluble cross-linked polystyrene (2) in 72% yield. Polystyrene 2 was treated with tributylphosphine (TBP) and water in THF to give soluble copolymer 3 possessing free thiol groups,which were successively protected by acetylation to give soluble copolymer (4). To regenerate an insoluble cross-linked polystyrene, the thiol groups were deprotected by NaBH4 and the generated thiols were oxidized to disulfide again by iodine to obtain the insoluble polymer with spherical shapes.
