聚合物支撑柔性有机二氧化硅杂化膜的制备与异丙醇脱水应用研究

Study of fabricating flexible organosilica membranes with high performance via flow-induced deposition method

以1,2-二(三乙氧基硅基)乙烷(BTESE)为硅源前驱体,通过溶胶-凝胶法在多孔聚合物基底上沉积桥联微孔有机二氧化硅活性分离层,制得高性能聚合物支撑的柔性有机二氧化硅"层杂化"膜.采用场发射扫描电子显微镜(SEM)、傅里叶变换衰减全反射红外光谱仪(ATR-FTIR)与X射线光电子能谱仪(XPS)等手段系统地考察了支撑体孔径大小以及有机二氧化硅溶胶含量对有机二氧化硅层的形貌以及杂化硅微孔网络的影响.随后,将该膜应用于异丙醇/水混合液(异丙醇质量分数90%)的蒸汽渗透脱水.研究发现,通过改变溶胶含量和基膜孔径,可有效调控柔性有机二氧化硅"层杂化"膜的结构与成膜质量,最终获得具有高性能的柔性有机二氧化硅杂化膜.结果表明,随着BTESE溶胶含量的增加,BTESE层厚度呈线性增加,溶胶质量分数为5%时,BTESE层厚约300 nm,膜BTESE 5%/NTR7430的分离因子最高可达1200,水通量约为1.77 kg/(m^(2)·h).此外,聚合物基膜的孔径尺寸也明显影响有机二氧化硅活性层的沉积量并最终影响膜的分离性能.

Using 1,2-bis(triethoxysilyl)ethane(BTESE)as a single precursor,an organosilica layer with high perm-selectivity was successfully deposited onto a porous polymer substrate via scalable sol-gel flow-induced deposition method.The effect of pore sizes of supports and concentrations of BTESE sol for the morphology of BTESE layer and nanoscale hybrid organosilica networks were examined using SEM,ATR-FTIR and XPS.In addition,the layered hybrid membranes were applied to the vapor permeation dehydration of isopropanol-water(90%/10%)solutions at 105℃.We investigated the influence of pore sizes of supports and concentrations of BTESE sol for the formation of the organosilica layer that covered the porous polymeric supports.We found that the thickness of BTESE layer increased linearly with an increase in concentration of BTESE sols.The layered membrane demonstrated a water flux of 1.77 kg/(m^(2)·h)and a separation factor of 1200 when using BTESE sol with concentration of 5%,whose thickness was 300 nm.Also,different pore sizes of polymeric supports exerted on the formation of the BTESE layer along with the effect on membrane performance.