Polymerization of methyl methacrylate and styrene in presence of phthalides

The radical polymerization of vinyl monomers (methyl methacrylate, styrene) has been investigated in the presence of phthalides of different structure , It is shown that the phthalides containing halogen atoms are, first of all, chain-transfer agents. The values of chain-transfer constants to them have been determined. It was found that the presence of chlorine atom bounded d irectly with carbon of phthalide cycle in a phthalide molecule results in c onsiderable growth of chain-transfer constant value to phthalide. If the ha logen is connected with aromatic group of phthalide, phthalide is a weak ch ain-transfer agent and the phthalide cycle is not included in polymer molec ule. It is shown that the phthalides containing mobile atoms of hydrogen ca n take part both in chain-transfer and in initiating system formation with the initiator. The function of phthalide is determined by structure of phth alide, monomer and initiator. The mechanism of phthalide participation in p olymerization has been discussed. The solutions of poly-MMA containing phth alide groups in macromolecules in concentrated sulfuric acid are intensivel y colored. This fact was used for quantitative determination of phthalide c ycles in a polymer chain, It has been found that when UV irradiated the bul ks of poly-MMA fluoresce and phosphoresce in a visible part of spectrum. (C ) 2001 Elsevier Science Ltd. All rights reserved.