Physical properties of hydrogels of poly(2-hydroxyethyl methacrylate) and copolymers with mono-methyl itaconate synthesized by bulk and solution polymerization

The physical properties found during the swelling process of poly(2-hydroxy ethyl methacrylate) (PHEMA) and of copolymers of HEMA with mono-n-methyl it aconate, synthesized by solution and bulk polymerization, are reported. The swelling kinetics were followed at four different temperatures (295, 300, 305 and 310 K). Experimental data follow second-order swelling kinetics, fr om where the kinetic rate constant k(infinity) and the swelling capacity at equilibrium W-proportional to were calculated as a function of temperature . The kinetic rate constant obeys Arrhenius behaviour. The following networ k parameters were determined for the hydrogels: Young's moduli E, effective crosslinking density v(e), molar mass per crosslink M-C, volume fraction p hi(2) and polymer-liquid interaction parameter chi. (C) 2000 Society of Che mical Industry.