以苯酚为溶剂,正硅酸四乙酯(TEOS)为硅源,采用溶胶-凝胶法制备了纳米SiO_2,将其引入到酚醛树脂中,最终制得改性酚醛泡沫。利用傅里叶变换红外光谱、扫描电镜、电子万能试验机等方法对泡沫材料进行表征。测试结果表明,纳米SiO_2与酚醛树脂成功发生反应形成共价键。扫描电镜显示,硅酯质量分数为5%时,泡沫具有最规整的形貌结构;同时,此添加量下的酚醛泡沫力学性能最优,压缩强度和弯曲强度较纯泡沫提高50%和95%。 Using phenol as solvent and tetraethylorthosilicate (TEOS) as silicon source, nano-SiO 2 was prepared by sol-gel method and introduced into phenolic resin to finally produce modified phenolic foam. The foam was characterized by Fourier transform infrared spectroscopy, scanning electron microscopy and electronic universal testing machine. The test results show that nano-SiO_2 and phenolic resin react successfully to form covalent bond. Scanning electron microscopy showed that the foam had the most regular morphology with the mass fraction of silicone ester being 5%. Meanwhile, the mechanical properties of the phenolic foam were the best at this amount of addition, the compressive strength and flexural strength increased by 50% and 95% .