BOOTSTRAP MODEL FOR THE COPOLYMERIZATION OF THE METHYL METHACRYLATE-STYRENE SYSTEM IN THE PRESENCE OF METHYL CYANOACETATE

The methyl methacrylate-styrene system in pure methyl cyanoacetate and in a methyl cyanoacetate/benzene mixture was examined by testing the theoretical calculations of the ''bootstrap model'' for the solvent ef fect in the copolymerization of the system. Methyl methacrylate center ed triads calculated according to the procedure given by Harwood plott ed against the methyl methacrylate ratio in copolymer showed that for the copolymer with the same composition, a different copolymer microst ructure was obtained. A similar but smaller effect can be observed for reexamined data in the literature for free-radical-initiated copolyme rization of the system in butyl alcohol and phenol. The inadequacy of the ''bootstrap model'' to describe exactly the solvent effects in the monomer-solvent systems investigated here is explained by the active H-atom in the solvents involved in the initiation and/or complexation reaction with methyl methacrylate.