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SynopsisDifferent isolated or competitive mechanisms have been experimentally observed in order to predict the kinetics of an epoxy-amine reaction in terms of various mathematical models based on different possibilities of reaction. Impurities such as water, glycols, and in general all donors of active hydrogen even at low concentrations significantly change the course of the reaction. We therefore decided to study the curing reaction of the epoxy resin, first as a commercial product and later purified, with m-xylylenediamine of known purity. The extent of cure has been followed and determined by differential scanning calorimetry (DSC) and infrared spectroscopy (FT-IR) . Purity. epoxy content and OH content were measured by liquid chromatography HPLC and wet analysis.A2 + E + (HX), 5 A3 + ( H X ) , A~ + E + (HX), 2 A~ + (HX),

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The kinetics of the reaction between trimethylolpropane (TMP) and epichlorohydrin (ECH) were studied. A mechanism is proposed which involves the synthesis of chlorohydrins, a previous stage which then leads to epoxy resin formation. From this mechanism a set of three coupled non-linear differential equations, (each equation corresponds to each chlorohydrin) was derived and numerical solutions were obtained using a Monte-Carlo method. The concentrations of chlorohydrins determined by this method (41.7, 35.7, and 22.5%) compare well with the experimental GPC results (42.7, 34.7, and 22.6%). The corresponding rate constants for the formation of the chlorohydrins were obtained. POLYMER €NG/N€€R/