改进的溶胶/凝胶法制备包覆型铝颜料

Aluminum pigments encapsulated by modified sol/gel method

为提高铝颜料的耐酸及耐碱性,同时保持铝颜料特有的金属光泽,采用改进的溶胶/凝胶法对铝颜料进行了表面包覆,结合FTIR、SEM、TEM、XPS等方法对包覆型铝颜料的微观形貌及包覆层成分进行了分析,并与传统溶胶/凝胶法制备的SiO2包覆的铝颜料的性能进行了对比.结果表明,采用改进的溶胶/凝胶法可以在铝颜料表面形成致密的网状包覆层,从而使其在pH=1的酸性介质及pH=11的碱性介质中的腐蚀保护因子分别达到99.8%和99.9%;与未包覆的铝颜料相比,采用改进的溶胶/凝胶法制备的包覆型铝颜料的光泽度仅下降3.2%,较好地保持了其本身的金属光泽.

Aluminum pigments were encapsulated by modified sol/gel method in order to improve their stability in acid and alkaline media.FTIR,SEM,EM and XPS were adopted to characterize the morphology and components of the encapsulation.Performances of aluminum pigments prepared by modified sol/gel method were compared with those prepared by traditional sol/gel method.It is found that compact netlike layers are formed on the surface of aluminum pigments encapsulated by modified sol/gel method,resulting that corrosion protection factors of aluminum pigments reach 99.8% in acid medium of pH=1 and 99.9% in alkaline medium of pH=11.Typically,gloss of aluminum pigments prepared by modified sol/gel method is only decreased by 3.2% compared with that of unencapsulated aluminum pigments,indicating that the gloss of aluminum pigments can be well kept with modified sol/gel method.