A novel route for the preparation of hybrid zwitterionic membranes containing both sulfortic and carboxylic acid groups

摘要

A novel route for the preparation of hybrid zwitterionic membranes containing both sulfonic and carboxylic acid groups is reported. Based on this synthetic methodology, a series of membranes were synthesized via sol-gel reaction, zwitterionization process, and the oxiclization of the -SH group. FTIR spectra confirmed the corresponding reactions. The properties of these prepared membranes were characterized by ion-exchange capacity (IEC), water content, and pure water flux, etc. The anion-exchange capacity (ATEC), total cation-exchange capacity (CIECtotal), and the CIEC of the sulfonic groups (CIECsulf) of the membranes coated for 1-3 times were in the range of 0.017-0.12, 0.1-0.53, and 0.029-0.14 mmol g(-1), respectively. The measurement of water content showed that it was independent of pH values whether for the membranes coated once or twice. Pure water flux revealed a downward trend with the increased coating times. The surface SEM images of the produced membranes exhibited that these membranes' textures could be affected highly by the curing temperature, and excessively higher curing temperature would lead the membranes to brittle and chasm. (c) 2007 Wiley Periodicals, Inc.