A facile surface segregation method was utilized to fabricate poly（vinyl alcohol）-polyethersulfone （PVA-PES） composite membranes. PVA and PES were first dissolved in dimethyl sulfoxide （DMSO）, then casted on a g...A facile surface segregation method was utilized to fabricate poly（vinyl alcohol）-polyethersulfone （PVA-PES） composite membranes. PVA and PES were first dissolved in dimethyl sulfoxide （DMSO）, then casted on a glass plate and immersed in a coagulation bath. During the phase inversion process in coagulation bath, PVA spontaneously segregated to the polymer solution/coagulation bath interface. The enriched PVA on the surface was further crosslinked by glutaraldehyde. Scanning electron microscopy （SEM）, X-ray photoelectron spectroscopy （XPS） and energy dispersive spectrometer （EDS） confirmed the integral and asymmetric membrane structure with a dense PVA-enriched surface and a porous PES-enriched support, as well as the surface enrichment of PVA. The coverage fraction of the membrane surtace by PVA reacned up to 86.8% when me PVA content m me membrane recipe was 16.7% （by mass）. The water contact angle decreased with the increase of PVA content. The effect of coagulation bath type on membrane structure was analyzed. The membrane pervaporation performance was evaluated by varying the PVA content, the annealing temperature, feed concentration and operation temperature. The membrane exhibited a fairly good ethanol dehydration capacity and long-term operational stability.展开更多
基金Supported by the State Key Development Program for Basic Research of China (2009CB623404)Program for New Century Excellent Talents in University,the Programme of Introducing Talents of Discipline to Universities (B06006)State KeyLaboratory for Modification of Chemical Fibers and Polymer Materials (Dong Hua University)
文摘A facile surface segregation method was utilized to fabricate poly（vinyl alcohol）-polyethersulfone （PVA-PES） composite membranes. PVA and PES were first dissolved in dimethyl sulfoxide （DMSO）, then casted on a glass plate and immersed in a coagulation bath. During the phase inversion process in coagulation bath, PVA spontaneously segregated to the polymer solution/coagulation bath interface. The enriched PVA on the surface was further crosslinked by glutaraldehyde. Scanning electron microscopy （SEM）, X-ray photoelectron spectroscopy （XPS） and energy dispersive spectrometer （EDS） confirmed the integral and asymmetric membrane structure with a dense PVA-enriched surface and a porous PES-enriched support, as well as the surface enrichment of PVA. The coverage fraction of the membrane surtace by PVA reacned up to 86.8% when me PVA content m me membrane recipe was 16.7% （by mass）. The water contact angle decreased with the increase of PVA content. The effect of coagulation bath type on membrane structure was analyzed. The membrane pervaporation performance was evaluated by varying the PVA content, the annealing temperature, feed concentration and operation temperature. The membrane exhibited a fairly good ethanol dehydration capacity and long-term operational stability.
