In this study, cardanol-based epoxidized novolac resins and methacrylic acid were used to produce cardanol-based epoxidised novolac vinyl ester resins. The reactions were conducted under nonstoichiometric condition using triphenylphosphine as catalyst in the temperature range of 80-100 degrees C with an interval of 5 degrees C. The first-order rate equation and mechanism based rate equation were examined. Parameters were evaluated by least square method. A comparison of mechnism based rate equation and experimental data showed an excellent agreement. Finally, Arrhenius equation and activation energy were presented. The specific rate constants, based on linear regression analysis, were found to obey Arrhenius equation. The values of activation energy, frequency factor, enthalpy, entropy, and free energy of the reaction revealed that the reaction was spontaneous and irreversible and produced a highly activated complex. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 118: 1979-1989, 2010