PROCESSING OF THERMOSETS.

The cure behaviour of commercial grade TGDDM-DDS mixtures is analysed by means of differential scanning calorimetry (DSC), high performance liquid chromatography (HPLC) and steady shear and dynamic viscosity measurements. The kinetic analysis of the DSC thermal scans suggested that DDS primary amine and epoxide etherification dominate the cure reactions. The Flory approach has been used to describe the molecular characteristics of the non linear polymerization of the TGDDM-DDS systems. The gelation limits in isothermal tests, calculated by considering the copolymerization of a tetrafunctional TGDDM with a bifunctional DDS, were in good agreement with the values determined in the rheological tests. The gelation theory was successfully combined with the WLF theory to describe the viscosity profiles of the reacting melt during the cure.