Functionalized graphene sheet-Poly(vinylidene fluoride) conductive nanocomposites
KAUST Grant NumberKUS-C1-018-02
MetadataShow full item record
AbstractPVDF nanocomposites based on functionalized graphene sheets, FGS prepared from graphite oxide, and exfoliated graphite, EG, were prepared by solution processing and compression molding. FGS remains well dispersed in the PVDF composites as evidenced by the lack of the characteristic graphite reflection in the composites. Although the α-phase of PVDF is seen in the EG-based composites, a mixture of α- and β-phases is present in the FGS analogs. SEM and TEM imaging show smooth fractured surfaces with oriented platelets of graphite stacks and obvious debonding from the matrix in the EG-PVDF composites. In contrast, the FGS-PVDF composites show a wrinkled topography of relatively thin graphene sheets bonded well to the matrix. Storage modulus of the composites was increased with FGS and EG concentration. A lower percolation threshold (2 wt %) was obtained for FGSPVDF composites compared to EG-PVDF composites (above 5 wt %). Lastly, the FGS-PVDF composites show an unusual resistance/temperature behavior. The resistance decreases with temperature, indicating an NTC behavior, whereas EG-PVDF composites show a PTC behavior (e.g., the resistance increases with temperature). We attribute the NTC behavior of the FGS based composites to the higher aspect ratio of FGS which leads to contact resistance predominating over tunneling resistance. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 888-897, 2009.
CitationAnsari S, Giannelis EP (2009) Functionalized graphene sheet-Poly(vinylidene fluoride) conductive nanocomposites. Journal of Polymer Science Part B: Polymer Physics 47: 888–897. Available: http://dx.doi.org/10.1002/polb.21695.
SponsorsThe authors thank A. Tamashausky of Asbury Carbons for providing graphite and Scott Gilje of Northrop Grumman Space Technology for providing graphite oxide used. S. Ansari acknowledge the Department of Science and Technology, Govt. of India for providing a BOYSCAST Fellowship. E. R Giannelis acknowledges the support of Award No. KUS-C1-018-02, made by King Abdullah University of Science and Technology (KAUST).