以正硅酸乙酯为原料，经溶胶-凝胶过程制备二氧化硅溶胶，再利用二甲基二乙氧基硅烷（DDS）对其进行改性，制备了疏水性二氧化硅凝胶。运用红外光谱，接触角，热重分析及原子力显微镜等测试方法对样品的结构，疏水性，热稳定性及形貌进行了分析。结果表明，改性后的样品是表面存在疏水基团-CH3的疏水凝胶；热稳定性较好，600℃之后没有明显的质量损失，热处理温度定于400℃可保证其疏水性；表面均一平整，孔隙率较高。

Hydrophobic silica gel was prepared by sol-gel process using tetraethoxy silicone(TEOS) as raw material, then the surface was chemically modified by diethoxydimethylsilane(DDS).The structure,hydrophobicity,thermal stability and surface morphology of the silica membrane were characterized by means of IR,angle of contact,TG-DTG and AFM.The results showed that the hydrophobic group—CH3 was on the surface of silica gel modified; the thermal stability was good, there was no significant mass loss after 600℃, sintered temperature set at 400℃，the silica membrane draw hydrophobic; The surface with large-porosity was regularly smooth.

[1] Pileni M P. Reverse micelles as microreactors [J].J.Phys Chem, 1993, 97(27):6961-6973.
[2] 艾翠玲, 贺延龄, 周孝德. 膜生物反应器在污水处理中的应用研究现状[J].长安大学学报(自然科学版), 2002, 22(4): 106-110.
[3] Wang Jue, Shen Jun, Zhou Bin, et al.Giant magnetoresistance in mechanically alloyed Ag-Cu-Fe alloys [J]. Nanostructured Materials, 1998, 10:893.
[4] 韦奇.微孔二氧化硅膜的制备、氢气分离以及水热稳定性研究[J].无机材料学报,2004,19(1):133-139.
[5] 郑文芝, 陈砺, 王红林,等. 疏水性二氧化硅气凝胶的合成及表征[J].硅酸盐通报,2008,27(6):1151-1155.
[6] 郭庆中，黄恒超，伍青，n(CH3)/n(Si)对甲基硅树脂防水性能的影响[J].有机硅材料，2006,20（1）：13~16
[7] 贾巧英，唐永兴，甲基化对多孔SiO2增透薄膜光化学稳定性能的影响[J].功能材料，2008,39（4）:580~583
[8] 张晔，吴东，孙予罕等，疏水增透SiO2膜的制备及其性能研究[J].物理化学学报，2002,18（4）：355~358
[9] Brinker C J, Schere G W. Sol-gel Science, the Physics and Chemistry of Sol-gel Processing [M]. San Diego: Academic Press, 1990.
[10] 曹冰, 朱从善, 胡耀铭. 色谱质谱联用技术研究30%二甲基二乙氧基硅烷/70%正硅酸乙酯复合醇盐的水解聚合行为[J].结构化学, 1998, 17(6): 439-443.
[11] 田辉，杨泰生，陈玉清. SiO2超疏水薄膜的制备和性能表征[J].化学进展，2008，27(9): 1435-1438.
[12] 王雪梅,刘燕,华志浩等.胞外聚合物对浸没式膜-生物反应器膜过滤性能的影响[J].环境科学学报,2005,25(12):1602-1607