Preparation, combustion and thermal behaviors of UV-cured coatings containing organically modified α-ZrP

The bisphenol A epoxy acrylate resin containing a small amount of organically modified alpha-zirconium phosphate (alpha-ZrP) was cured within seconds upon UV irradiation at ambient temperature. The UV-curing behavior was investigated by fourier transformedinfrared spectroscopy (FTIR). The microstructures were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The transparency and the combustion were examined by the UV-vis transmission spectra and Microscale Combustion Calorimeter (MCC), respectively. The ultraviolet-visible spectra of the cured films showed no obvious absorbance over a range of 400-800 nm, which revealed that the cured films were transparent. The results of MCC revealed that heat release rate (HRR) of the films decreased with the contents of organic alpha-ZrP (OZrP). Thermal behavior of the cured films was studied by thermogravimetric analysis (TGA), which indicated that with increasing the contents of OZrP, the char yields of UV-cured films were enhanced. Viscoelastic property of photocured nanocomposites was evaluated by dynamic-mechanical analysis. The effects of OZrP on the properties of UV curable films were critically evaluated in this paper.