The Study of Volume Electrical Resistivity and Mechanical Property of Double Continuous Phase PVDF/CBT Composite Containing Carbon Black and Graphite

Abstract

The Poly(vinylidene fluoride)(PVDF)/Cyclic Butylene Terephthalate (CBT)/carbon black (CB)/graphite (GR) composites were prepared by melting blend method and were studied by milliohmmeter and material testing machine. The results showed that due to the formation of CB and GR conductive network, the volume electrical resistivity of PVDF/CBT/CB/GR composites linearly decreased as graphite content increased at below 4 wt% of graphite, but it in turn increased when graphite content was higher than 4 wt%. Flexural strength showed an increase at below 1.6 wt% of GR and gradually decreased as GR content increased further. Differently, flexural modulus of composites declined as GR content increased. In all composites, the flexural strength was more than 25 MPa, which satisfied with the requirements of bipolar plates.