无机材料学报 ›› 2018, Vol. 33 ›› Issue (9): 969-975.DOI: 10.15541/jim20170570

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遮光剂掺杂Al2O3-SiO2气凝胶/莫来石纤维毡复合材料的高温隔热性能研究

朱召贤1, 王飞2, 姚鸿俊1, 董金鑫1, 龙东辉1   

  1. 1. 华东理工大学 化学工程联合国家重点实验室, 上海 200237;
    2. 中国空间技术研究所, 北京 100074
  • 收稿日期:2017-11-27 修回日期:2018-02-07 出版日期:2018-09-20 发布日期:2018-08-14
  • 作者简介:朱召贤(1991–), 男, 博士研究生. E-mail: zxzhu1991@163.com

High-temperature Insulation Property of Opacifier-doped Al2O3-SiO2 Aerogel/Mullite Fiber Composites

ZHU Zhao-Xian1, WANG Fei2, YAO Hong-Jun1, DONG Jin-Xin1, LONG Dong-Hui1   

  1. 1. State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China;
    2. China Academy of Space Technology, Beijing 100074, China
  • Received:2017-11-27 Revised:2018-02-07 Online:2018-09-20 Published:2018-08-14
  • About author:ZHU Zhao-Xian. E-mail: zxzhu1991@163.com

摘要:

分别以TiCl4和ZrOCl2·8H2O作为钛源和锆源, 经过溶胶-凝胶和超临界CO2干燥过程, 将遮光剂粒子TiO2和ZrO2掺入到Al2O3-SiO2气凝胶, 并进一步以莫来石纤维毡为增强相制备出具有一定力学性能的耐高温气凝胶复合材料, 分别探究了两种遮光剂粒子对复合材料的微观结构、力学性能和热导率的影响。结果显示: 遮光剂粒子的引入可以有效阻止气凝胶在高温下的塌陷和团聚, 保持气凝胶高孔隙率的特性; 复合材料呈现典型的气凝胶填充纤维结构, 并且具有轻质(0.21~0.24 g·cm-1)和高强度(弯曲强度为0.98~1.26 MPa)的优异性能, 拓展了材料的实用性; 在 1050℃的高温下, 由于 TiO2 和 ZrO2 粒子对红外电磁波具有吸收和散射作用, 可以将复合材料的热导率由0.098 W·m-1·K-1分别降低至0.085 W·m-1·K-1和0.076 W·m-1·K-1, 从而有效提高材料的高温隔热性能。

 

关键词: Al2O3-SiO2气凝胶, 红外遮光剂, 热导率, 高温隔热性能

Abstract:

Infrared opacifier-doped Al2O3-SiO2 aerogel/mullite fiber composites were successfully prepared through a mixed Sol-Gel and supercritical drying process by using TiCl4 and ZrOCl2·8H2O as the source of TiO2 and ZrO2, respectively. Effects of two kinds of infrared opacifier on microstructure, mechanical property and thermal conductivity of composites were studied. The results show that introduction of infrared opacifier effectively prevent the aerogels from collapse and agglomeration when exposed to high temperature, leading to high-level retention of porosity. The aerogel/mullite fiber composites demonstrate a typical structure of aerogel filled fibrous fiber with marvelous properties—low density (0.21-0.24 g·cm-1) and high bending strength performance (0.98-1.26 MPa), which expands brilliant potential in many areas of application. When exposed to high temperature of 1050℃, the thermal conductivity of TiO2 and ZrO2 doped composites can be significantly reduced from 0.098 W·m-1·K-1 to 0.085 W·m-1·K-1 and 0.076 W·m-1·K-1, respectively, which could be attributed to outstanding scattering and absorbing ability of the infrared opacifiers to the infrared electromagnetic wave. All results indicate that the addition of infrared opacifiers is a promicsing approach to enhance high-temperature properties of aerogel materials.

Key words: Al2O3-SiO2 aerogels, infrared opacifier, thermal conductivity, high temperature insulation properties

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