炭气凝胶的溶胶-凝胶合成工艺及其相关结构研究进展  

Progress on Sol-gel Synthesis and Related Structures of Carbon Aerogels

作　　者：门静 冯军宗[1] 姜勇刚[1] 李良军 胡艺洁 冯坚[1] MEN Jing;FENG Junzong;JIANG Yonggang;LI Liangjun;HU Yijie;FENG Jian(Science and Technology on Advanced Ceramic Fibers and Composites Laboratory,College of Aerospace and Engineering,National University of Defense Technology,Changsha 410073,China)

机构地区：[1]国防科技大学空天科学学院新型陶瓷纤维及其复合材料重点实验室,长沙410073

出　　处：《硅酸盐学报》2024年第8期2709-2721,共13页Journal of The Chinese Ceramic Society

基　　金：湖南省自然科学基金(2023JJ30632);国家重点研发计划(2022YFC2204403);湖南省重点研发计划(2022GK2027)。

摘　　要：具有耐高温和低热导率特性的炭气凝胶是惰性气氛下的理想高温隔热材料。炭气凝胶优异的隔热性能与其特殊的纳米孔隙和骨架结构密不可分,因此,实现纳米结构的可控制备是进一步优化炭气凝胶隔热性能并拓展其实际应用的关键。本文首先基于气凝胶热传导理论讨论了气凝胶结构与隔热性能的关系,而后综述了炭气凝胶隔热材料的溶胶–凝胶制备工艺对其结构影响的研究进展,最后,对炭气凝胶隔热材料的制备工艺研究方向进行了展望。Carbon aerogels are one of the most promising materials for high-temperature thermal insulators under inert atmosphere owing to their properties of low density,low thermal conductivity,ultra-high temperature resistance in inert atmospheres,and high infrared specific extinction coefficient.At present,there have been some studies on carbon aerogel thermal insulations at home and abroad,but most of them focus on the improvement of mechanical,antioxidant and ablation resistance properties,the simplification and low cost of the preparation process,as well as the ultralight and superelastic properties of carbon aerogel.There are fewer studies on how to further optimize the high-temperature thermal insulation performance of carbon aerogel thermal insulations.The excellent thermal insulation properties of carbon aerogels are inseparable from their special nanopore and skeleton structures,therefore,realizing the controllable preparation of the structures of carbon aerogels is the key to further optimizing their thermal insulation properties and expanding their practical applications.This paper introduces the relationship between the structure and thermal insulation property of aerogel,summarizes the research progress on the effect of sol-gel preparation process on the structure of carbon aerogel thermal insulation,and provides an appropriate outlook on the research direction of the preparation process.The thermal conductivity of carbon aerogel represents its thermal insulation performance to a certain extent,and can be used as an indicator for the initial screening of carbon aerogel thermal insulation.Generally,the lower the thermal conductivity of the material,the better its thermal insulation performance.Based on heat transfer theory,the thermal conductivity of carbon aerogel is represented as the sum of contributions from solid thermal conductivity,gaseous thermal conductivity,radiative thermal conductivity and coupling thermal conductivity.Under certain environmental conditions,the thermal conductivity is mainly close

关 键 词：炭气凝胶 隔热材料 溶胶–凝胶法 

分 类 号：TQ427.26[化学工程]