The thermal stability of some semi-interpenetrated polymer networks based on epoxy resin and aromatic polyurethane

Thermal stability of some semi-interpenetrating polymer networks based on aromatic polyurethane and a crosslinked epoxy resin were investigated by a simultaneous thermal analysis coupling of thermogravimetry–dynamic scanning calorimetry–Fourier transform infrared spectroscopy–mass spectroscopy. The samples were heated at four different heating rates (5, 10, 15 and 20 K min−1) and the kinetic parameters were determined by isoconversional methods of Friedman and Flynn–Wall–Ozawa. The form of the kinetic model which best described the global decomposition process was calculated by multiple linear regressions. The gases evolved were identified by Fourier transform infrared spectroscopy and mass spectroscopy.