纤维增强二氧化硅气凝胶复合材料的制备和低温性能  

Preparation and Low-temperature Properties of Fiber Reinforced SiO_2 Aerogel Composites

作　　者：马佳[1] 沈晓冬[1] 崔升[1] 孔勇[1] 邵高峰[1] 吴晓栋[1] 

机构地区：[1]南京工业大学材料科学与工程学院,材料化学国家重点实验室,南京210009

出　　处：《材料导报》2015年第20期43-46,63,共5页Materials Reports

基　　金：长江学者和创新团队发展计划(IRT1146);江苏高校优势学科建设工程;江苏先进无机功能复合材料协同创新中心;江苏省科技支撑计划(工业)项目(BE2014128);宿迁市科技基础设施项目(2013-39)

摘　　要：以正硅酸四乙酯(TEOS)为前驱体制备SiO2溶胶,并分别与玄武岩纤维和玻璃纤维复合,经超临界干燥工艺制备了疏水耐低温SiO2气凝胶复合材料。利用傅里叶红外光谱仪、接触角分析仪、激光法导热仪、万能试验机、氮气吸附法对SiO2气凝胶复合材料的结构和性能进行了表征。结果表明:两种纤维增强SiO2气凝胶复合材料在常温及低温下均具有良好的疏水性能和隔热性能,玄武岩纤维增强SiO2气凝胶复合材料和玻璃纤维增强SiO2气凝胶复合材料的接触角分别为148°和142°,常温热导率分别为0.030 W·m-1·K-1和0.026 W·m-1·K-1,-50℃时的热导率分别为0.027 W·m-1·K-1和0.024 W·m-1·K-1,在低温条件下,体积无明显收缩。纤维的加入提供了力学支撑,两种材料不仅在常温下具有良好的力学性能,而且在低温下的力学性能有所增强。Hydrophobic silica aerogel composites were prepared by using basalt fibers or glass fibers as reinforcement,TEOS as raw material via supercritical drying process.Its structure and properties were characterized by Fourier transform infrared spectroscopy,contact angle analyzer,laser flash apparatus,universal testing machineand pore size distribution.The aerogel composites exhibit excellent hydrophobic property andthermal insulation properties at ambient temperature and even low temperature.The thermal conductivities of basalt fiber reinforced SiO2 aerogel composites and glass fiber reinforced SiO2 aerogel composites at 25 ℃ are only 0.030 W·m^-1·K^-1 and 0.026 W·m^-1·K^-1,respectively,and the thermal conductivities at-50 ℃ are only 0.027 W · m^-1·K^-1 and 0.024W·m^-1·K^-1,respectively.Volume does not shrink obviously under cryogenic conditions.With the reinforcement of fibers,themechanical propertyof materials at low temperatureis better than that at ambient temperature.

关 键 词：SIO2气凝胶 纤维 疏水 热导率 保冷材料 

分 类 号：O611.62[理学—无机化学]