摘要
以陶瓷纤维为增强相,正硅酸乙酯(TEOS)为普通前驱体、甲基三甲氧基硅烷(MTMS)为改性前驱体,乙醇(EtOH)为助溶剂,采用溶胶凝胶-常压分级干燥法制备了CF/SiO2轻质多孔气凝胶复合材料。采用正交试验法优化了原料配比,当原料TEOS、MTMS、EtOH、H2O、HCl、NH3·H2O的摩尔比为0.4∶0.6∶6∶5∶2×10^-3∶3×10^-3,凝胶反应温度为30℃时,制备的复合隔热材料孔隙率最高。通过单因素实验探索了陶瓷纤维长度及加入的体积质量对CF/SiO2气凝胶密度、孔隙率、收缩率及压缩强度的影响,结果表明添加0.8wt%长度为1 mm的陶瓷纤维效果最好。CF/SiO2气凝胶复合材料密度为0.1206 g·cm^-3,孔隙率为90.4%,收缩率为4.06%,抗压强度(10%应变)为118 KPa。
CF/SiO2 lightweight porous aerogel composites were prepared by sol-gel and atmospheric pressure fractionation drying method using ceramic fibers as reinforcing phase and tetraethyl orthosilicate(TEOS)as precursors,methyltrimethoxysilane(MTMS)as modified precursor and ethanol(EtOH)as solvent.Orthogonal test was used to optimize the ratio of raw materials.The results showed that the porosity of the composite insulation material was highest when the molar ratio of TEOS,MTMS,EtOH,H2O,HCl,NH3·H2O was 0.4∶0.6∶6∶5∶2×10^-3∶3×10^-3,and the gel reaction temperature was 30℃.The effects of ceramic fiber length and volume quality on the density,porosity,shrinkage and compressive strength of CF/SiO2 aerogels were investigated by single factor experiments.The results show that the ceramic fiber with 0.8 wt%and length of 1 mm is the best.The density of CF/SiO2 aerogel composites is 0.1206 g·cm^-3,porosity is 90.4%,shrinkage rate is 4.06%,and compressive strength is 118 KPa at 10%strain.
作者
李小玉
徐春涛
陈平清
肖丽凤
Li Xiaoyu;Xu Chuntao;Chen Pingqing;Xiao Lifeng(Zhongshan Torch Polytechnic, Guangdong Zhongshan 528436;Zhongshan Tolytechnic, Guangdong Zhongshan528400;Maoming Vocational Technical College, Guangdong Maoming 525000.)
出处
《化工时刊》
CAS
2020年第5期20-24,共5页
Chemical Industry Times
基金
广东省科技厅项目(2015A010105003)。
