Synthesis of PVDF/CNT and their functionalized composites for studying their electrical properties to analyze their applicability in actuation & sensing

The actuation properties of piezo-electric polyvinyl di fluoride (PVDF) can be improved by mixing electro-resistive carbon nano tubes (CNT's) and various mechanisms have been highlighted recently. Herewith, we proposed a simple route for the synthesis of PVDF/CNT composite by mixing a proper concentration of PVDF with CNT in N-Methyl-2-pyrrolidone (NMP) by using solution phase co-precipitation techniques. We observed that at a certain concentration ratio of PVDF and CNT, it formed well crystalline morphology with specific structures. After optimizing their concentrations, we mixed carbonic and sulphonic acid functionalized CNT, with PVDF at a certain ratio and prepared the acid functionalized PVDF/CNT composites. The composite materials were characterized by various spectroscopic and microscopic techniques such as XRD, FTIR, thermal and FE-SEM analyses. From the FE-SEM analysis, the sheikh kabab morphology was observed in PVDF while more pronounced and oriented structure was found in case of CNT as well as their carbonic acid functionalized product. As an application, the synthesized materials are studied for actuation purposes by investigating their properties using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) analysis. It was observed that the actuation properties of PVDF was enhanced while mixed with CNT and carbonic acid functionalized CNT although it remained unchanged in case of sulfonic acid functionalized CNT. In case of PVDF and carbonic acid functionalized CNT, a higher saturation current of 2.7 mA was observed while for bare PVDF in NMP, a reduced value of 0.0087 mA was observed. The present synthesis route and the application process is simple, less time consuming and could be extended for the fabrication of other composite materials for their potential application as actuator and in other technologically important energy related fields. (C) 2016 Elsevier B.V. All rights reserved.