Vinyl polymerization. 410. Polymerizations of vinyl monomers initiated by poly(styrene‐co‐sodium acrylate) or poly(methyl methacrylate‐co‐sodium methacrylate). A verification of the concept of hard and soft hydrophobic areas and monomers

Abstract

It was found that the copolymers of sodium acrylate (AA‐Na) with styrene (St) and of sodium methacrylate (MAA‐Na) with methyl methacrylate (MMA) could polymerize vinyl monomers in an aqueous phase without the usual initiator. Interestingly, there was a definite composition of the copolymer for the polymerization of a given monomer; for example, when poly(St‐co‐AA‐Na) was used, St, MMA, vinyl acetate, ethyl acrylate, methyl acrylate, and acrylonitrile were polymerized by the copolymer having mole ratios of AA‐Na:St of 0.61:0.29, 0.47:0.53, 0.38:0.62, 0.30:0.70, 0.24:0.76, and 1.00:0, respectively. The copolymers of various compositions can form hydrophobic areas (HAs) in the water phase. As has been repeatedly reported, the polymerization proceeds in the HAs, and the following new hypothesis was recently proposed that the hard (the less hydrophilic) HA prefers to incorporate the hard monomer and the soft (the less hydrophobic or the more hydrophilic) HA prefers to incorporate the soft monomer. The results mentioned above support this hypothesis.