【Abstract】 The silica/polymer nanocomposites were obtained via in situ ultraviolet light irra diation of the dispersion system containing epoxylacrylate, aminoacrylate, 1,6 hexanediol diacry late , sensitizer 1173 and 20 nm silica particles. The results showed that the hardness, tensile strength and modulus of the nanocomposites were increased with increasing silica content. The silica nanocomposite with 2 5%(wt) of silica had pencil hardness of grade 6, tensile strength of 50 MPa and modulus of 1640 MPa. The initial thermal decomposition temperature of the nanocomposite was increased considerably at <400 K and decreased at >600 K . The thermal decomposition loss was 83 4% at near 800 K. The nanocomposites showed a strong ultraviolet absorbency in region of 200~400 nm and the absorbency at 400~ 800 nm increased with increasing silica content. the transmittance at 400 nm was 25% and fluorescence at 700 nm was observed when the composite was excited with 365 nm wave.更多还原