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 directly with carbon of phthalide cycle in a phthalide molecule results in considerable growth of chain-transfer constant value to phthalide. If the halogen is connected with aromatic group of phthalide, phthalide is a weak chain-transfer agent and the phthalide cycle is not included in polymer molecule. It is shown that the phthalides containing mobile atoms of hydrogen can take part both in chain-transfer and in initiating system formation with the initiator. The function of phthalide is determined by structure of phthalide, monomer and initiator. The mechanism of phthalide participation in polymerization has been discussed. The solutions of poly-MMA containing phthalide groups in macromolecules in concentrated sulfuric acid are intensively colored. This fact was used for quantitative determination of phthalide cycles in a polymer chain. It has been found that when UV irradiated the bulks of poly-MMA fluoresce and phosphoresce in a visible part of spectrum.