Thermal curing behavior of benzoxazine functional polysilsesquioxane nanospheres

Abstract Benzoxazine functional polysilsesquioxane (Bz-PSQ) nanoparticles were synthesized using a simple sol-gel method in this work, which is characterized by scanning electron microscopy (SEM) and show a uniform spherical morphology. The benzoxazine functional structure of nanospheres was studied by Fourier transform infrared spectroscopy (FTIR) and water contact angle measurement. The curing kinetics and curing behavior of benzoxazine structure in nanoshperes were investigated by differential scanning calorimeter (DSC) and In situ FTIR. The activation energy of the curing reaction is 148.0 ± 14.1 kJ mol −1 for Kissinger and 149.4 ± 13.4 kJ mol −1 for Ozawa method, respectively. Differential FTIR spectra and 2D correlation analysis were utilized to discern the sequence of molecular variations during the curing process and the possible polymerization mechanism of benzoxazine structure was proposed as well.