Cardanol-based novolac resins were separately prepared with different mole ratios of cardanol-to-formaldehyde with different acid catalysts. These resins were epoxidized with epichlorohydrin, in basic medium, at 120 degrees C. The resins were, separately, blended with different weight percentages of carboxyl-terminated butadiene acrylonotrile copolymer and cured with polyamine. Structural changes during blending were studied by FTIR spectroscopic analysis. Coats-Redfern equation was utilized to calculate the kinetic parameters, viz., order of decomposition reaction (n), activation energy (E), pre-exponential factor (Z), and rate decomposition constant (k), for the decomposition of the samples. It was found that the degradation of the epoxies and their blend samples proceeded in two steps. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 114:1694-1701, 2009