| As a kind of thermoset resin, epoxy resin has excellent properties, such as good cohesive, mechanical and anti-corrosion properties, and also has the merits both easy processing and modeling. So it has been widely applied in plastics, paints, electrical materials and encapsulation materials. Along with the increasing demand for application, exploitation of advanced epoxy resin by sol-gel process is of current scientific interest. Because of increased interaction between phases in hybrid materials, where inorganic phase is often covalently bonded with the organic polymer, they offer superior properties compared to classical materials. But phase separation is often found in the SiO2/ Epoxy Resin hybrid material preparation, which will effect greatly on the hybrid materials' properties. The extensive applications of hybrid materials depend on improvement of morphology of the phase separation or the components of hybrid material disperse in molecular scale.In this paper, SiO2 Epoxy Resin hybrid materials are formed by the sol-gel process of tetraethyl orthosioate (TEOS) and [H2N(CH2)3Si(OC2H5)3] (KH-550). KH-550 is a functionalized silane (coupling agent), and can undergo both the sol-gel polymerization of the alkoxy groups as well as curing of the epoxy rings to form a hybrid network containing covalent bonds between organic and inorganic phases. Their preparation theories, chemical structure and characteristics were studied.It was found that different catalysts caused different effects on the reaction process and product's morphology during preparation of the SiO2 sol.①Hydrolysis reaction of TEOS was fast in the beginning of the reaction when acidic catalyst was used. On the contrary, it was slowly carried out when basic catalyst was adopted.② Different morphologies of SiO2 sol system were found via TEM when using different catalysts. It was homogeneous when acidic catalyst was used and was multiphase when basic catalyst was used.SiO2/ Epoxy Resin hybrid materials were prepared by one step or two steps. In the first one. The quantity of impregnant and TEOS influence on the properties of nanocomposites were examined, The decentralization of Silicon dioxide in the epoxy resin were examined by transmission electron microscopy (TEM), The fracture surfaces of hybrid materials were examined by scanning electron microscopy (SEM),The thermal properties of hybrid materials were examined by differential scanning calorimetry (DSC). The results reveal that the more quantity of impregnant are introduced the better of the transparence is, but the mechanical and thermal properties decline;The integrated properties of the materials attain a peak at approximately 3%TEOS content while none of impregnant. The SiC>2 particles were about 20nm, and distributing symmetrical. The crystal temperature of the compositions enhance over 30°C, and the thermal transmutation temperature was improved.In the two steps, the quantity of TEOS^ KH-550 and temperature influence on the properties of hybrid materials were studied. The results reveal that the properties of the materials attain a peak at approximately 3%TEOS content, 2%KH-550 content, react at 60 °C, the SiC>2 particles were about 20nm.The mechanical and thermal properties of the hybrid materials were improved greatly as compared with the pure epoxy resin.In a word, SiCV Epoxy Resin hybrid materials have been successfully prepared in this paper and these hybrid materials exhibited good mechanical and thermal properties.
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