CONTROLLED RADICAL POLYMERIZATION BY DEGENERATIVE TRANSFER - EFFECT OF THE STRUCTURE OF THE TRANSFER AGENT

Control of the radical polymerization of styrene and acrylates has been achieved by using alkyl iodides in a degenerative transfer process. Various transfer agents of the type R-I were explored. Of those examined, 1-phenylethyl iodide, iodoacetonitrile, and iodoform were found to be effective in controlling molecular weights and for providing polymers with relatively low polydispersities, M(w)/M(n) less than or equal to 1.5. Relatively good control has been also achieved with perfluoroalkyl iodides, whereas most alkyl and aryl iodides have been ineffective transfer agents. Also explored were the effects of initiator structure and reaction temperature on the polymerization systems.