苯基修饰的疏水微孔二氧化硅膜的制备与表征

采用苯基三乙氧基硅烷(PTES)和正硅酸乙酯(TEOS)作为前驱体,通过溶胶-凝胶法制备了苯基修饰的SiO2膜材料。利用扫描电镜、N2吸附、视频光学接触角测量仪、热重分析、红外光谱等测试手段对膜的孔结构以及疏水性能进行了表征,最后还研究了修饰后膜材料在室温条件下的单组份气体渗透和分离性能。结果表明,随着PTES加入量的增大,膜材料的疏水性逐渐增强,当PTES/TEOS和H2O/TEOS的化学计量比分别达到0.6和9.6时,膜材料对水的接触角达到115±0.5°,仍保持良好的微孔结构,其孔体积为0.17cm3/g,孔径为0.4-0.5nm。室温下氢气在修饰后SiO2膜的输运既遵循发生在微孔孔道的表面扩散机理也遵循发生在较大孔道或者微缺陷的努森扩散机理,膜材料的H2渗透率达到1.49×10-6mol?m-2?Pa-1?s-1,H2/CO2 和H2/SF6的理想分离系数分别达到4.64和365.59

Preparation and Characterization of Hydrophobic Microporous Silica Membranes Modified by Phenyl Groups

Silica membranes modified with phenyl groups were synthesized through the acid-catalyzed co-hydrolysis and condensation reaction of tetraethyl orthosilicate(TEOS) and phenyltriethoxysilane(PTES).The pore structure and hydrophobic properties of the modified silica membranes were characterized by means of SEM,nitrogen adsorption,water contact angle measurement,TG and FTIR.The single gas permeation and permselectivity of the hydrophobic silica membranes were also investigated at room temperature.The results sh...