Redox‐initiated radical polymerization of 2‐hydroxyethyl methacrylate, 3. Copolymerization with nine monomers, effect of structure and media on the reactivity of monomers

Abstract

AbstractCopolymerization of 2‐hydroxyethyl methacrylate (HEMA) with eight acrylic monomers and vinyl acetate using redox initiators was carried out in DMF and in aqueous medium. Reactivity ratios were calculated according to the general copolymerization equation using Fineman‐Ross, Kelen‐Tüdős and the YBR methods. The results indicate that reactivity of the methacrylates towards growing HEMA radicals decreased in the order, methyl methacrylate > 2‐dimethylaminoethyl methacrylate > 2,3‐epoxypropyl methacrylate. Reactivity of the acrylates decreased in the order butyl acrylate > ethyl acrylate > methyl acrylate. In the HEMA‐acrylate systems, the intrinsic viscosity of the copolymers decreased with increasing content of the acrylates in the copolymer. On the other hand, the intrinsic viscosity of the copolymers of HEMA‐MMA showed an increasing trend with increasing content of MMA in the copolymer. Changing the polymerization medium from DMF to water resulted in copolymers having a higher HEMA content.