Photo-polymerization behaviors of bisphenol-A epoxy diacrylate (EPA) and six kinds of EPA-derived resins containing different amounts of carboxylic acid, urethane, amide, and imide groups were studied by a photo differential scanning calorimetry. The dark polymerization was performed and pseudo-steady state assumption of growing radicals was made to obtain the kinetic constants for propagation, bimolecular termination, monomolecular termination, and the concentration of growing radicals of different resins as a function of extent of reaction. Compared with EPA, it was found that the rate of polymerization and kinetic constants of the six resins were relatively small because the mobility of reacting species in resins was restricted by carboxylic acid, urethane, amide, and imide groups. Finally, three different photo-initiators were used to initiate the polymerization, and their kinetic behaviors were compared. The effect of tertiary amine group of photo-initiator on the rate of polymerization of resins having carboxylic acid group and the initiator efficiency were discussed.
Relation:
Journal of Applied Polymer Science 115(4), pp.1982-1994
