Characterization of pore structure of PHEMA-based slabs

The texture of highly porous poly(2-hydroxyethyl methacrylate) (PHEMA) slabs prepared by bulk radical copolymerization of 2-hydroxyethyl methacrylate (HEMA) and ethylene dimethacrylate (EDMA) in the presence of porogens (cyclohexanol, dodecan-1-ol or saccharose) was studied by mercury porosimetry and solvent (water, cyclohexane) regain. Mercury porosimetry gave information on both the macroporosity (50 nm-1 μm) and superporosity (>1 μm) in dry state. The main part of pores in the prepared slabs was in the macroporous range. Low values of the apparent density of investigated polymers indicated the presence of closed pore structures. The effect of both the type of porogen and cross-linking degree on porous properties was discussed.