1.School of Civil Engineering & Architecture,Northeast Petroleum University,Daqing 163318;
2.School of Energy Science and Engineering,Harbin Institute of Technology,Harbin 150001
Abstract: SiO2 aerogel particles are mostly hydrophobic modified by modifying organic functional groups on the surface.However,this method has the problem that the hydrophobic functional group breaks and the hydrophobicity decreases after heating.At present,the variation of number of functional groups and hydrophobicity with temperature and heating time is not clear,and the relationship between the number of functional groups and the contact angle has not yet been clarified.SiO2 was hydrophobic modified by trimethylchlorosilane.The change of methyl functional groups number and the hydrophobicity of aerogel with temperature and heating time was analyzed by using fourier transform infrared spectroscopy and contact angle test.Then,the relationship between the contact angle and the number of functional groups was clarified.The results showed that increasing the heating temperature and heating time can reduce the amount of methyl groups on the surface of aerogel particles,which reduced the static contact angle of material.When the temperature reached 600℃,the methyl functional groups completely disappeared and the material losed its hydrophobicity.The contact angle of material was approximately inversely proportional to the loss of surface methyl groups.
赵海谦, 刘城昊, 韩瑞, 王忠华, 刘立君, 刘晓燕, 高继慧. 温度对SiO2气凝胶表面疏水官能团数量及疏水性的影响[J]. 化工新型材料, 2019, 47(3): 207-210.
Zhao Haiqian, Liu Chenghao, Han Rui, Wang Zhonghua, Liu Lijun, Liu Xiaoyan, Gao Jihui. Influence of temperature on hydrophobic functional group and hydrophobicity of silica aerogel. New Chemical Materials, 2019, 47(3): 207-210.
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