Thermal degradation mechanisms of epoxy composites filled with tin particles

This article reports an evaluation study of the thermal degradation mechanisms of electrically insulating and conducting epoxy/Sn composites by using solid-state kinetic approaches and structural characterizations. Comparison of the thermoanalytical data of epoxy/Sn composites with pure epoxy shows that the addition of tin in epoxy catalyzes the thermal degradation of epoxy and the catalytic ability of tin depends upon its contents in epoxy. Kinetic modeling of the phenomena elaborates the thermal behaviors of epoxy/Sn composites in terms of the comparison of their activation parameters and reaction models. Friedman's differential and Arshad–Maaroufi's generalized linear integral isoconversional methods are used to obtain the variation in activation energies with the advancement of reaction. Advanced reaction model determination methodology is effectively employed to evaluate the reaction mechanisms of epoxy/Sn composites. Kinetic analysis suggests that tin increases the thermal degradation rate of epoxy by lowering the activation energy barrier of reaction. It is worth noticing that the parameters of the probable reaction model, i.e., Šesták Berggren have been found nearly the same for pure epoxy and epoxy/Sn composites, revealing weak epoxy–tin interactions in the composites. The mechanistic information obtained by kinetic analysis fairly agrees with the scanning electron microscopy and X-ray diffraction results. POLYM. COMPOS., 38:1529–1540, 2017. © 2015 Society of Plastics Engineers