文献类型：期刊文献

英文题名：Fabrication of SiCN(O) Aerogel Composites with Low Thermal Conductivity by Wrapping Mesoporous Aerogel Structures over Mullite Fibers

作者：Wang, Wei[1];Pang, Le[2];Jiang, Ming[2];Zhu, Yaping[1];Wang, Fan[1];Sun, Jingwen[2];Qi, Huimin[1]

机构：[1]East China Univ Sci & Technol, Sch Mat Sci & Engn, Key Lab Specially Funct Polymer Mat & Related Tech, Minist Educ, Shanghai 200237, Peoples R China;[2]Shanghai Inst Space Equipment, Lab Aerosp Thermal Control Prod Adv Mfg Technol, Shanghai 201109, Peoples R China

年份：2022

卷号：15

期号：24

外文期刊名：MATERIALS

收录：;EI(收录号：20225313323689);WOS:【SCI-EXPANDED(收录号:WOS:000902766800001)】；

基金：This research was funded by Key Laboratory of Specially Functional Polymeric Materials and Related Technology of Ministry of Education, East China University of Science & Technology, the Fundamental Research Funds for the Central Universities (Grant No. 50321041918013 and 50321041917001), and the Innovation Foundation of Shanghai Aerospace Science and Technology, China (NO. SAST2019-068).

语种：英文

外文关键词：SiCN(O) ceramic aerogel; composite; pore structure; thermal conductivity; ambient pressure impregnation; thermal insulation optimization

摘要：Silicon-based ceramic aerogels obtained by the polymer pyrolysis route possess excellent thermophysical properties, but their poor mechanical properties limit their broader applicability in thermal insulation materials. Herein, SiCN(O) ceramic aerogels were prepared under the toughening effect of a crosslinker (hexamethylene diisocyanate, HDI), which maintains the structural integrity of the aerogel during the wet gel-to-aerogel conversion. The aerogel maintained a high surface area (88.6 m(2) g(-1)) and large pore volume (0.21 cm(3) g(-1)) after pyrolysis. Based on this, mullite-fiber-reinforced SiCN(O) aerogels composites with outstanding thermal insulation properties and better mechanical performance were synthesized via ambient pressure impregnation. Furthermore, the effect of the impregnation concentration on the mechanical and insulation properties of the composites was investigated. The results revealed that the composite prepared with a solution ratio of 95 wt.% exhibited a low density (0.11 g cm(-3)) and a low thermal conductivity (0.035 W m(-1) K-1), indicating an similar to 30% enhancement in its thermal insulation performance compared to the mullite fiber; the mesoporous aerogel structures wrapped on the mullite fibers inhibited the gas thermal conduction inside the composites.