高强度块状C-Al_2O_3复合气凝胶的制备  

Synthesis of monolithic C-Al_2O_3 composite aerogel with high strength

作　　者：仲亚[1] 孔勇[1] 沈晓冬[1] 崔升[1] 滕凯明[1] 林本兰[1,2] 张君君[1] 

机构地区：[1]南京工业大学材料科学与工程学院,江苏南京210009 [2]南京工业大学学报编辑部,江苏南京210009

出　　处：《南京工业大学学报（自然科学版）》2012年第5期26-29,88,共5页Journal of Nanjing Tech University(Natural Science Edition)

基　　金：国家自然科学基金资助项目(10976013);江苏省普通高校研究生科研创新计划(CXLX11_0344)

摘　　要：采用溶胶-凝胶法和CO2超临界干燥工艺,并经高温热处理过程得到C-Al2O3复合气凝胶。通过N2吸附-脱附实验研究热处理对气凝胶孔结构参数的影响;利用X线衍射技术表征气凝胶在热处理过程中的相结构变化;采用扫描电子显微镜观察气凝胶的微观形貌,并对气凝胶进行强度测试。结果表明:C-Al2O3复合气凝胶具有均匀的三维网络结构,而且成块性好,热处理后C-Al2O3复合气凝胶仍然具有高的比表面积。C-Al2O3复合气凝胶的最高压缩强度可达9.07 MPa,大大提高了气凝胶材料的力学性能。C-Al2O3 composite aerogel was prepared by sol-gel method combined CO2 supercritical fluid drying and high temperature thermal treatment process.The variation of pore structure and specific surface area was analyzed based on the nitrogen adsorption-desorption isotherm.The changes in phase structure during the heating process were characterized by X-ray diffraction.The micro-morphology was studied by scanning electron microscopy,and the strength was tested.Results showed that the C-Al2O3 composite aerogel had a uniform three-dimensional network without crack.C-Al2O3 composite aerogel was also had a high specific surface area and a super strength after thermal treatment.The strength of C-Al2O3 composite aerogel was up to 9.07 MPa,thus the mechanical property of aerogel material was improved.

关 键 词：溶胶-凝胶 CO2超临界干燥 C-Al2O3复合气凝胶 压缩强度 

分 类 号：TQ138.1[化学工程—无机化工]