Thermodynamic excluded volume effect on gelation in free-radical crosslinking copolymerization of allyl benzoate with diallyl terephthalate

In order to discuss further the significance of the thermodynamic excluded volume effect on gelation in free-radical monovinyl/divinyl crosslinking copolymerizations, allyl benzoate was copolymerized with diallyl terephthalate in the presence of poly(benzyl methacrylate) (poly(BzMA)) having different molecular weights. Thus, the deviation of actual gel point from theoretical one became smaller with an increase in the molecular weight of poly(BzMA) and, moreover, SEC-MALLS measurements clearly afforded supporting evidence for the increased occurrence of intermolecular crosslinking. These results are expected as a result of reduced contribution of the thermodynamic excluded volume effect on gelation.