Polymerization of methyl methacrylate and styrene in the presence of phthalides

The free-radical polymerization of methyl methacrylate and styrene in the p resence of phthalides of varying structure was studied. It was shown that t he halogen-containing phthalides act as the chain-transfer agents; the rate constants of chain transfer to these compounds were determined, It was dem onstrated that the presence of chlorine atoms directly linked to the carbon of a phthalide cycle leads to an appreciable increase in the rate constant of chain transfer. It was found that phthalides containing mobile hydrogen s can be involved in the reactions of chain transfer and formation of initi ating species with initiator. The mechanism for the participation of phthal ides in the polymerization process is discussed. It was established that th e PMMA blocks fluoresce, some of them phosphoresce in the visible spectral range upon UV irradiation, and PMMA solutions in the concentrated sulfuric acid are intensively colored.