The hindered curing behavior of epoxy-phenol mixtures with the presence of 18MMT (modified by acidic primary octadecylamine) using triphenephosphine (TPP) as a catalyst was investigated by DSC. The mechanism proposed is based on the analysis of these obtained curing behaviors with DSC experiments by changing the components in the epoxy-phenol/18MMT blends. Due to the reaction between TPP and the active H in 18MMT, the catalytic effect of TPP is reduced greatly, which pushed the epoxy resin cured by 18MMT at higher temperature. Such mechanism can depict the delayed curing reaction with incorporation of different amounts of 18MMT correctly. By changing TPIP contents and the type of organic modifier bearing no active H. the subsequent resulted curing reaction is quit in good agreement with those predicted by the proposed mechanism, which supports our hypothesis in further. (c) 2006 Elsevier Ltd. All rights reserved.