Effect of polymer-filler interactions on PTC behaviors of LDPE/EPDM blends filled with carbon blacks

The dependence of electrical resistivities on the temperature of different polymer systems (including rubbers and plastic/rubber blends) loaded with carbon blacks (including oxidized and normal carbon blacks) were studied. We found that polymer-carbon black interactions could greatly influence the electrical resistivity and temperature relations of the polymer composites. The polymer blends filled with oxidized carbon black, or the elastomer which has polar functional groups filled with carbon black, have a very weak negative temperature coefficient (NTC) effect, which is due to the strong polymer-filler interactions. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 1885–1890, 1997