Xu Rong, Ibrahim Suhaina M, Kanezashi Masakoto, Yoshioka Tomohisa, Ito Kenji, Ohshita Joji, Tsuru Toshinori
Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, School of Petrochemical Engineering, Changzhou University , Changzhou 213164, China.
ACS Appl Mater Interfaces. 2014 Jun 25;6(12):9357-64. doi: 10.1021/am501731d. Epub 2014 Jun 9.
Microporous organosilica membranes with ethane, ethylene, and acetylene bridges have been developed and the extensive microstructural characterization has been discussed in relation with separation properties of the membrane. The organosilica network structure and the membrane performances can be controlled by adjusting the flexibility, size, and electronic structure of the bridging groups. A relatively narrow size distribution was obtained for the novel acetylene-bridged sol by optimizing the sol synthesis. Incorporation of larger rigid bridges into organosilica networks resulted in a looser microstructure of the membrane, which was quantitatively evaluated by N2 sorption and positron annihilation lifetime (PAL) measurements. Molecular weight cutoff (MWCO) measurements indicated that the acetylene-bridged membrane had a larger effective separation pore size than ethane- and ethylene-bridged membranes, leading to a relatively low NaCl rejection in reverse osmosis. In quantum chemical calculations, a more open pore structure and increased polarization was observed for the acetylene-bridged networks, which led to a significant improvement in water permeability. The present study will offer new insight into design of high-performance molecular separation membranes.
已开发出具有乙烷、乙烯和乙炔桥联的微孔有机硅膜，并结合膜的分离性能对其广泛的微观结构表征进行了讨论。有机硅网络结构和膜性能可通过调节桥联基团的柔韧性、尺寸和电子结构来控制。通过优化溶胶合成，新型乙炔桥联溶胶获得了相对较窄的尺寸分布。将较大的刚性桥联基团引入有机硅网络会导致膜的微观结构更疏松，这通过N2吸附和正电子湮没寿命（PAL）测量进行了定量评估。截留分子量（MWCO）测量表明，乙炔桥联膜的有效分离孔径比乙烷和乙烯桥联膜大，导致反渗透中NaCl截留率相对较低。在量子化学计算中，观察到乙炔桥联网络具有更开放的孔结构和增强的极化，这导致水渗透性显著提高。本研究将为高性能分子分离膜的设计提供新的见解。
