Abstract: Nano scale SiO2 is prepared by sol-gel process using phenol as solvent and TEOS as silica source,and then is added into phenolic resin.Ultimately,the modified phenolic foam materials are prepared.The foam materials prepared are characterized by Fourier transform infrared spectroscopy,scanning electron microscopy (SEM) and electronic universal testing machine.The test results show that the nano scale SiO2 reacts with phenolic resin successfully to form covalent bonds.SEM shows that when the mass concentration of TEOS is 5%,the foam materials prepared have the most regular morphology and the best mechanical properties,and the compressive strength and bending strength are 50% and 95% higher respectively than pure phenolic resins.
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