Synthesis and characterization of superclean thermoreversible copolymer hydrogels

A series of hydrogels that show inverse thermo-response have been synthesiz ed by simultaneous radiation polymerization and crosslinking, Superclean ge ls were obtained by irradiating the monomers (hydroxyethylacrylate and hydr oxypropylacrylate) in bulk or in aqueous solutions without any additive. By variation of the monomer concentration, co-monomer ratio, irradiation temp erature and absorbed dose, hydrogels with various swelling charactheristics were obtained. By increasing the ratio of the more hydrophilic ethylacryla te, the critical temperature of the gel can be shifted to higher temperatur es, and by increasing the monomer concentration or the dose, gels with bett er mechanical characteristics albeit lower swelling degree could be obtaine d. (C) 1999 Elsevier Science Ltd. All rights reserved.