Conductive Carbon Black/ Carbon Fiber/ Polyolefin Composites: Conductivity and Mechanical Properties

The effect of carbon black and carbon fibers on the conductivity and mechanical properties of HDPE/EPDM blend was investigated. It was found that HDPE/EPDM (70/30 wt %) has lower percolation threshold and volume resistivity than individually carbon blackfilled HDPE and EPDM due to double percolation effect. Carbon fibers were added to the polymer/carbon black composites to enhance the conductivity and mechanical properties. The electrical conductivity of composites with different ratios of carbon black (CB) content to carbon fiber (CF) content was studied. Mechanical properties, including tensile strength, elongation at break and impact strength of the conductive composites were evaluated. The results showed that incorporation of CB and CF in the composites enhances tensile strength, but decreases elongation at break and impact strength of the composites. In mechanical properties, CF content plays a more important role than does CB content. Also, it is concluded that using CF to replace some parts of the CB in CBfilled composites can enhance electrical and mechanical properties simultaneously.