PHOTOPOLYMERIZATION OF DI-FUNCTIONAL AND TETRAFUNCTIONAL METHACRYLIC MONOMERS IN A POLYMERIC MEDIUM - KINETICS AND EVIDENCE OF REACTION-DIFFUSION THROUGHOUT THE PHOTOPOLYMERIZATION REACTION

The photopolymerization behavior and reaction kinetics of ethylhexyl m ethacrylate (EHMA) and ethylene glycol dimethacrylate (EGDMA) monomers in styrene-butadiene-styrene block copolymer (SBS) were studied. For both monomers, di- and tetrafunctional, reaction diffusion was found t o be the only mechanism of termination when the polymerization is carr ied out in this polymeric medium, that is, reaction diffusion controls the termination reaction from the beginning of the reaction. The poly merization of EGDMA in polystyrene and polybutadiene showed similar be havior to that in SBS. Also, the relationship between the individual r ate constants k(t) and k(p) was studied, and a constant ratio of these kinetic constants was found.