Abstract: UV curable inorganicorganic composite coatings containing SiO2 nanoparticles based on the epoxy acrylate (EA) were prepared by the blending method. The structure， thermal stability and physical properties of the composite coatings were investigated. The results indicated that Si—O—Si crosslinked network structures are generated in the coatings due to the incorporation of SiO2 nanoparticles， which contributed to improve the thermal stability of the coatings. The composite coating with 5% mass fraction of SiO2 nanoparticles exhibits the most excellent thermal stability. With the increase of the content of SiO2， the gloss of the coatings decreases. Moreover， the reasonable amounts of SiO2 addition can improve the hardness of the coatings. When the mass fraction of SiO2 is 3%~5%， the composite coating exhibits 3H pencil hardness.

Key words: UV curable coating, composite coating, epoxy acrylate, silica nanoparticles, thermal stability