A series of glycidyl methacrylate (GMA)-ethylene dimethacrylate (EGDM) copolymers of varying compositions were synthesized by free-radically triggered thermal frontal polymerization (FP) as well as by suspension polymerization (SP) using azobisisobutyronitrile [AIBN] as initiator. The two sets of copolymers were characterized by IR spectroscopy and mercury intrusion porosimetry, for determination of epoxy number and specific surface area. Frontal polymerization was more efficient, yielding greater conversions at much shorter reaction times. The self-propagating frontal polymerization also generates microporous material with narrow pore size distribution. It yields higher internal pore volume and surface area than suspension polymerization, surface morphologies are, however, inferior.

Frontal polymerization of 2-hydroxyethyl methacrylate was investigated to study the effect of type and concentration of initiator, solvent and diluent on the existence of a front, on front velocity as well as front temperature. A significant effect of the type of initiator and its concentration was recorded. Poly(2-hydroxyethyl methacrylate) (PHEMA) was obtained predominantly as a gel. The different gels were evaluated for water and cyclohexane gain and porosity, and the mechanism of gel formation is discussed. Amongst the three diluents used (silica gel, β-cyclodextrin and silica sol), gel formation was highest in the presence of silica sol (≈ 42%). Pore dimensions were less than 15 nm and pore size distribution was narrow. PHEMA networks showed significantly higher water regain due to swelling than attributed to the pore volume as estimated by mercury porosimetry or cyclohexane regain. Kinetics of the equilibrium swelling ratio was studied.