The Effect of Carbon Black on Electrical, Thermal-Oxidative Stability, and Structural Properties of Polypropylene/Clay Nanocomposite

Abstract

An effort to improve electrical property of Polypropylene (PP)/Clay nanocomposite was conducted. Carbon black (CB) was introduced into PP/Clay to enhance that property as required for conductive polymer composites (CPCs) application. The compositions of CB on PP/Clay were varied at 3, 5, and 7 percent hundred resin (phr). In this research, all composites were prepared by melt mixing using an internal mixer at 222 °C, 83 rpm, and 10 minutes. A compatibilizer, PP-grafted-Maleic Anhydride (PP-g-MA), was used to facilitate dispersion of clay layers and CB particles on PP matrix. The electrical property of composite was evaluated from their surface resistivity using insulation tester. Meantime thermal-oxidative stability property was analyzed from oxidative induction time (OIT) data using Differential Scanning Calorimetry (DSC) instrument. The presence of CB dramatically decreased surface resistivity of PP/Clay from 6.98 x 1013 ohm to 7.35 x 106 ohm by adding CB 7 phr. OIT of PP/Clay dropped 155% compare with neat PP. On the other hand, the addition of CB 7 phr into PP/Clay improved OIT of PP/Clay up to 22 %. The interlayer structure of clay was investigated using X-ray Diffraction (XRD) to find out the synergistic effect between clay and CB. Actually, clay interlayer spacing did not change due to the addition of CB.