纤维毡种类对柔性SiO2气凝胶复合毡性能的影响

以甲基三乙氧基硅烷（MTES）为硅源，酸碱两步法制备溶液，以玻璃纤维毡、陶瓷纤维毡复合、玄武岩纤维毡为基材，制备柔性SiO2气凝胶复合毡。对SiO2柔性气凝胶复合毡进行微观形貌、机械强度、导热系数、疏水角表征，探究纤维毡种类对SiO2柔性气凝胶毡性能的影响。研究表明，在相同工艺条件下，玻璃纤维复合毡导热系数最低、密度最小、疏水性能最优、机械性能最好，常温下导热系数0.294W/（m·K），密度0.158g/cm3，疏水角149.9°，拉伸强度1.27MPa；陶瓷纤维复合毡体积收缩率最大、压缩强度最小，体积收缩率12.5%，压缩强度24N（20%ε）、44N（30%ε）；玄武岩纤维复合毡体积收缩率最小、压缩强度最大，体积收缩率7.8%，压缩强度91N（20%ε）、267N（30%ε）。

Effect of fiber felt types on the properties of flexible silica aerogel composite felt

With methyl triethoxysilane (MTES) as the silicon source, the solution is prepared by two-step acid-base method. And with glass fiber felt, ceramic fiber felt and basalt fiber felt as the substrate, the flexible SiO2 aerogel fiber composite felt is prepared. The micromorphology, mechanical strength, thermal conductivity and hydrophobic angle of SiO2 aerogel composite felt are characterized to explore the influence of fiber felt types on the properties of aerogel felt. The results show that under the same process, aerogel glass fiber composite felt has the lowest thermal conductivity, the smallest density, and the best hydrophobic and mechanical performance. Its thermal conductivity at room temperature is 0.294W/(m·K), the density is 0.158g/cm3, the hydrophobic angle is 149.9°, and the tensile strength is 1.27MPa. Aerogel ceramic fiber composite felt has the largest volume shrinkage rate and the smallest compressive strength, with volume shrinkage rate of 12.5% and compressive strength of 24N (20%ε) and 44N (30%ε). Aerogel basalt fiber composite felt has the smallest volume shrinkage rate and the largest compressive strength, with volume shrinkage rate of 7.8% and compressive strength of 91N（20%ε）and 267N（30%ε）.