疏水性有机-无机SiO_2复合薄膜的制备及性能研究

Preparation and Research of Organic-inorganic Hydrophobic SiO_2 Composite Films

以正硅酸乙酯为主要原料，用长链三甲氧基硅烷GH2n＋1Sit（OCH3）3（n=7～12）取代含氟有机硅烷，采用溶胶凝胶法制备了无氟疏水性纳米SiO2复合薄膜．利用差热热重分析研究胶体特性；利用分光光度计对胶体进行红外光谱分析；采用扫描电子显微镜检测了薄膜表面质量，利用划痕法和盐雾腐蚀对薄膜进行了附着力和腐蚀试验．结果表明，为避免疏水功能团—CH3被破坏，薄膜的热处理温度应低于300℃，热处理后薄膜中的SiO2含量增加．对基材采用多层涂覆及逐层热处理，可提高薄膜疏水性能，平均接触角达到110．2°．薄膜附着力达到GBl720—88相应一级，具有良好的防腐蚀性能．

Hydrophobic non-fluorine SiOe coextruded film was prepared from Si（OC2Hs5）4 and CnHe2n＋1 Si（OCH3）3 （n= 7-12） instead of Fluoro-organosilane using Sol-Gel method. The character of colloid was inferred from thermogravimetric analysis （TG） and differential thermal analysis （DTA）. IR transmittance of films heat-treated at different temperature was examined. The surface of film was characterized by SEM. Anticorrosion and cohesion properties were also discussed here. The results indicate that the heat treatment temperature of the composite thin film should be lower than 300℃ to avoid the burning of -CH3. After heat treatment, the content of SiO2 of film increases. The average contact angle of thin films increases with the increment of coating times, and the max value is 110. 2°. The films have better hydrophobicity, anticorrosion and cohesion, which amount to the best grade according to GB1720-88.