SiO_2/环氧树脂基纳米复合材料的室温和低温力学性能

MECHANICAL PROPERTIES OF EPOXY COMPOSITES FILLED WITH SiO_2 NANO-PARTICLES AT ROOM AND CRYOGENIC TEMPERATURES

利用溶胶-凝胶法制备了SiO2/环氧树脂基复合材料,研究了材料的室温与低温(77K)下的力学性能。结果表明,适量SiO2的引入提高了室温与低温下材料的拉伸强度、断裂伸长率和冲击强度,即SiO2含量在2%时可同时起到增强、增韧作用。采用扫描电镜(SEM)和透射电镜(TEM)分别对复合材料的断口形貌和高温焚烧后残留物纳米颗粒进行了观察。还利用动态力学分析(DMA)研究了二氧化硅的引入对复合材料的影响。

Nanometer silica particles were added to epoxy resin by the sol-gel method. The mechanical properties such as impact strength, tensile strength and elongation at the break point of the materials were studied at room and cryogenic temperatures. The fracture surfaces were examined by scanning electron microscopy (SEM). The ashes of the composites were collected after burning off the nanocomposites and the silica nano-particles were observed by transmission electron microscope (TEM). At room temperature, the tensile strength and elongation at break attain a peak at approximately 2% silica content where the impact strength reaches the maxium. However, at cryogenic temperature, the tensile strength increases with the increasing silica content. DMA (dynamic mechanical analysis) reveals that the glass transition temperature and storage modulus are increased.