Kinetics of epoxy resins formation from bisphenol‐A, bisphenol‐S, and epichlorohydrin

Abstract The kinetics of formation of epoxy resins derived from bisphenol‐A, bisphenol‐S, and epichlorohydrin under stoichiometric conditions was considered. The kinetics of reaction was studied by taking into account the consumption of the added alkali and epoxide value of epoxide oligomers. The obtained results satisfactorily explained that the reactivity of bisphenol‐A with epichlorohydrin is higher than that of bisphenol‐S, the rate of dehydrochlorination of chlorohydrin ether in the presence of alkali and water is much higher than that of the rate of condensation of phenolic hydroxyl group with epichlorohydrin. The apparent reaction order of phenolic groups with epichlorohydrin and terminal epoxide group in the oligomer are all second order. The rate constants and activation energy were determined. The results are discussed. © 1993 John Wiley & Sons, Inc.