Thermal behavior of poly(2-hydroxyethyl methacrylate-maleic acid) networks

Poly(2-hydroxyethyl methacrylate-maleic acid) [P(HEMA/MA)] networks were prepared by radiation-induced polymerization of 2-hydroxyethyl methacrylate and maleic acid in aqueous solution. The thermal properties of the P(HEMA/MA) networks were investigated with differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The thermal behavior of these networks was also compared with PHEMA homopolymer. The glass transition temperature (T-g) of PHEMA homopolymer was found as 87 degreesC. On the other hand, T-g of the P(HEMA/MA) networks decreased from 118 degreesC to 113 degreesC with increasing amount of MA in the network. It was observed that the initial thermal degradation temperature of P(HEMA/MA) networks did not change much with the MA content. However, the thermal degradation reaction mechanism of these copolymeric networks was different from PHEMA homopolymer. (C) 2003 Elsevier Science Ltd. All rights reserved.