| This paper is concerned with UV-curable nano-hybrid coating. Instead of simply blending nano-particle with matrix resin, the coating were prepared by so call sol-gel process using tetrathoxysilan(TEOS) as precursor in the precence of UV curable epoxy acrylic resin. The effect of content of TEOS on gel time, silica size, and coatings' morphology were studied. Changes in pencil hardness, adhesion, impact strength and gloss of the films with the content of SiO2 were investigated. The effect of curing conditions on curing rate were also studied.The silica sizes of coatings were about 100nm and increased with the content of TEOS, observed by TEM. The effect of EA resin on the sol-gel process was studied. It was found that when EA content is higher than 85%, the so-gel system became turbid while EA content is lower than 85%, the system was transparent and homogeneous.It was showen that incorporation nano-particles of SiO2 into EA coating could much enhance hardness, adhesion, impact strength, and wear resistance of the EA coating. But there is an optimum content of SiO2, beyond which these mechanic performance would reduce.The results indicated that formulation of the coatings would affect the curing rate and mechanic properties of the films. Improving the content of multifunctional monomer could accelerate the curing rate. Furthermore, we found that there is also optimum content of photoinitiator where curing rate is the highest.EA resin was modified by grafting with maleic anhydride. The mechanic properties of these modified EA films were better than EA coatings before modifying.
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