The effect of mixed diluent on the porous structure of crosslinked PMMA beads

In this work copolymer beads, based on MMA (methyl methacrylate) and EGDM ( ethylene glycol dimethacrylate), were prepared by suspension polymerization . A mixed solvent, composed of two different solvents, namely toluene and c yclohexane, was used as the diluent in the polymerization medium. The porou s structure of the beads was found to be affected by the solvent compositio n used to dissolve the monomers initially. It was observed that the porosit y and pore size increased gradually with the increase of cyclohexane conten t of the solvent composition. It was also detected that the pore radii chan ged from 2-10 nm to 700-1000 nm as the cyclohexane content of the diluent c hanged from nil to 100 % (v/v) respectively. These results indicate that po re size of the copolymer beads is a function of solvent composition.