SiOC sol-gel slurry was prepared by co-hydrolysis and mixture using methyl trimethoxysilane (MTMS) and vinyl triethoxysilane (VETS) as raw materials and adding SiO2 aerogel powder.3D printing and ambient pressure drying were used to prepare SiOC-based aerogel,and the microscopic morphology,thermal insulation and mechanical properties of the samples were explored.The results showed that this aerogel had low density and shrinkage rate,with a thermal conductivity of 0.03665W·m-1·K-1.After the 3D-printed SiOC-based aerogel was modified by filling with TEOS sol-gel,its thermal conductivity effectively reduced to as low as 0.017W·m-1·K-1,and the compressive strength increased to 1.87MPa.The SiO2 aerogel formed by TEOS filling filled the macro pores and micro size macropore structure of 3D-printed SiOC-based aerogel,thus effectively reducing the gas phase heat transfer paths and improving the thermal insulation performance.
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基金资助
国家自然基金项目(51972222)
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