Synthesis and characterization of hydrophilic copolymers

Abstract

Two composition ratios of poly[N-isopropylacrylamide (NIPAAm)-co-2-hedroxy ethyl acrylate (2-HEA)] were prepared in ethanol/water mixtures (v/v, 1/1) using ammonium persulfate (APS) as initiator. The hydrophilic copolymers were characterized by DSC, TGA, GPC and SEM. The results showed that molecular weight, Tg, thermal stability increase with increase of NIPAAm in the copolymers. The increase of molecular weight is interpreted in terms of increasing the formation of primary radicals in high ratio of NIPAAm in the copolymer. SEM showed that the polymer became more hydrophilic with increasing the ratio of NIPAAm in the copolymer.