Classical and pseudoliving radical copolymerization of vinyl acetate and acrylic acid in methanol

The homogeneous free-radical copolymerization of vinyl acetate and acrylic acid is studied at 50 and 70°C in methanol with and without the reversible addition-fragmentation chain-transfer agent benzyl dithiobenzoate. It is shown that, under conditions of reversible addition-fragmentation chain-transfer copolymerization, the limiting conversion is 32% and the number-average molecular mass increases linearly with conversion. At the same time, in the absence of the reversible addition-fragmentation reversible chain-transfer agent, the conversion of the monomers amounts to 63% and the molecular mass of the copolymers decreases with conversion.