Structure and Properties of Electrospun Poly(vinylidene fluoride)/Polycarbonate Membranes After Hot-Press

Poly(vinylidene fluoride) (PVDF)/polycarbonate (PC) dispersed solutions were electrospun into ultrafine core/shell fibers and modified by hot-press. Morphology, tensile properties, porosity, and liquid absorption of the electrospun membranes as well as the crystallinity of PVDF were examined before and after hot-press. Results showed that the tensile strength and tensile modulus of the electrospun membranes increased after hot-press, especially when poly(methyl methacrylate) (PMMA) or benzyl triethylammonium chloride (BTEAC) was introduced for the formation of distinct core/shell fiber structure. The elongation of the hot-pressed electrospun PVDF/PC membrane with addition of BTEAC was also significantly enhanced by reason of the clearest core/shell structure. The crystallinity of PVDF did not change too much before and after hot-press, however the porosity and liquid absorption of the hot-pressed electrospun membranes decreased to about 58% and around 75-90%, respectively, with no significant differences between PVDF/PC, PVDF/PC/PMMA, and PVDF/PC with BTEAC membranes. This study could be an example of electrospun membranes in multi-polymer components and it could be extended to other systems of electrospinning for applications in filtration and so on. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 122: 774-781, 2011