Synergistic effect on crystalline structure of polyvinylidene fluoride nanocomposites with multiwalled carbon nanotube loading by a twin screw extruder

Abstract

Polyvinylidene fluoride (PVDF)/multiwalled carbon nanotube (MWCNT) composites were prepared by using twin screw extruder at various (0-5 wt %) MWCNT loadings. Field Emission Scanning Electron Microscope (FESEM) micrographs showed a relatively good dispersion and random distribution of MWCNT in PVDF matrix. The physical and dielectric properties increased gradually with the increase in MWCNT content but the thermal stability decreased. The DSC result revealed the increase in crystallinity of the PVDF matrix. Wide angle X-Ray diffraction (WAXD) result showed a large shoulder at 2y of 20.78 with increasing in MWCNT content. The experimental percolation threshold for the surface resistance of PVDF/MWCNT composites were estimated and clearly observed at 4 wt % of MWCNT loading. V C 2011 Wiley Periodicals, Inc. J Appl Polym Sci 121: 226-233, 2011

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