Homo- and copolymerization of vinyl phosphates and phosphonates

Abstract Phosphorus–containing monomers of general formulae magnified image homopolymerized, copolymerized with methyl methacrylate, vinyl acetate, and styrene under a variety of conditions, and the products were characterized. The results of homopolymerization show that yields and the degree of polymerization depend on the purity of the monomers, method of polymerization, and the initiator used. With the exception of monomers containing β‐chloroethoxy group attached to the phosphorus atom, polymers obtained from the dialkyl vinyl phosphates had higher molecular weights than the corresponding dialkyl vinyl phosphonates. Dialkyl isopropenyl phosphates polymerized less readily than the dialkyl vinyl phosphates and diethyl styryl phosphate did not polymerize at all. An attempt is made to explain these results in terms of steric hindrance, charge distribution, and chain transfer. Examination of the copolymerization products, with a number of techniques used, indicates that these consist of polymers with a wide range of compositions and molecular weights. The copolymers with methyl methacrylate appear to consist of a large block of poly(methyl methacrylate) at one end and a smaller block of polymer formed from the vinyl phosphate or phosphonate at the other. Similar conclusions are drawn about copolymers involving styrene. It is likely that the monomer units in copolymers with vinyl acetate are randomly distributed.