SiO2气凝胶具有成本低、制造工艺简单、化学性质稳定、密度小、超高比表面积等优点,是应用最广泛的高温保温隔热材料。以Si28和Si40为Si源,仲丁醇铝为Al源,乙醇为溶剂,采用酸碱催化、CO2超临界干燥法制备了Al掺杂SiO2气凝胶。结果表明:所得产品高温热处理后均为非晶态无定型结构,无掺杂SiO2气凝胶线收缩率为24.34%,Al掺杂SiO2气凝胶线收缩为14.05%,且在高温热处理后有较大的比表面积和孔体积,说明Al掺杂SiO2气凝胶具有较好的耐高温性能和高温下的绝热性能,这是因为Al元素的掺入使气凝胶在形成过程中产生了很多细小的纳米空洞,热处理过程中Al-Si-O发生化学反应形成双金属氧化物,使气凝胶的氧化物骨架支撑力更强。
SiO2 aerogel has the advantages of low cost,simple manufacturing process,stable chemical properties,small density,and ultra-high specific surface area,etc.It is the most widely used high-temperature thermal insulation material.Al doped SiO2 aerogels were prepared by acid-base catalysis and CO2 supercritical drying method using Si28 and Si40 as Si sources,aluminium tri-sec-butoxide as Al source and ethanol as solvent.The results showed that the products obtained after high temperature heat treatment exhibited amorphous and non-crystalline structures.The linear shrinkage of undoped SiO2 aerogel was 24.34%,while that of Al-doped SiO2 aerogel was 14.05%,with a larger specific surface area and pore volume after high-temperature heat treatment,indicating that Al-doped SiO2 aerogel had a better high-temperature resistance and insulation performance at high temperatures.This was because the incorporation of Al element caused many fine nano cavities in the formation of aerogels.Furthermore,Al-Si-O reacted chemically to form bimetallic oxides during heat treatment,which made the support of oxide skeleton of the aerogels stronger.
[1] 方赟,李斌.气凝胶材料的研究进展[J].上海塑料,2022,50(6):14-20.
[2] 丁勇花.SiO2气凝胶隔热材料的制备及其导热性能研究[J].功能材料,2022,53(9):9122-9126.
[3] 张忠伦,孙沈涵,徐长伟,等.不同硅源制备二氧化硅气凝胶研究进展[J].中国建材科技,2023,32(1):52-61.
[4] 王飞,刘朝辉,丁逸栋,等.SiO2气凝胶的制备方法及其应用研究进展[J].装备环境工程,2015,12(6):84-92.
[5] 张宁.SiO2气凝胶复合保温材料的制备工艺及性能研究[J].新型建筑材料,2022,49(10):85-87,113.
[6] 杜翠凤,李利军,王远常,等.SiO2气凝胶纤维隔热复合材料的常压制备及性能表征[J].硅酸盐通报,2022,41(12):4406-4411,4418.
[7] Peng F,Jiang Y,Feng J,et al.A facile method to fabricate monolithic alumina-silica aerogels with high surface areas and good mechanical properties[J].Journal of the European Ceramic Society,2020,40(6):2480-2488.
[8] 李艳华,吴一凡,韩琦.SiO2气凝胶材料增强技术研究进展[J].复合材料科学与工程,2022(8):117-128.
[9] 吴佳臻,徐长伟,张忠伦,等.Al2O3-SiO2复合纳米气凝胶材料耐高温性能研究[J/OL].复合材料科学与工程,https://kns.cnki.net/kcms/detail/10.1683.tu.20230306.1802.002.html.
[10] Shafi S,Navik R,Ding X,et al.Improved heat insulation and mechanical properties of silica aerogel/glass fiber composite by impregnating silica gel[J].Journal of Non-Crystalline Solids,2019,503-504:78-83.
[11] 张路佳,姜勇刚,冯军宗,等.纤维增强Al2O3-SiO2气凝胶隔热复合材料研究进展[J].硅酸盐通报,2022,41(12):4397-4405.
[12] Li L,Feng J,Cai H,et al.Research progress on alumina aerogel composites for high-temperature thermal insulation[J].Journal of Inorganic Materials,2021,36(7):673-684.
[13] Rezaei S,Zolali A M,Jalali A,et al.Novel and simple design of nanostructured,super-insulative and flexible hybrid silica aerogel with a new macromolecular polyether-based precursor[J].Journal of Colloid and Interface Science,2020,561:890-901.
[14] 范虹霞,冯新星,金万慧,等.ZrO2/SiO2改性隔热纤维素微纤维气凝胶复合织物的制备及其性能[J].现代纺织技术,2023,31(1):185-193.
[15] 张凤梅,李振杰,唐石云,等.不同金属离子掺杂TiO2-SiO2气凝胶光催化降解啶虫脒的研究[J].云南大学学报(自然科学版),2022,44(6):1241-1248.
[16] 张勇,高相东,姚佳祺,等.SiO2-Al2O3气凝胶及纤维增强复合材料制备技术研究进展[J].材料导报,2022,36(23):57-65.
