Abstract
Polymeric composites based on a combination of polyolefins such as ultra-high-molecular-weight poly(ethylene), high-density poly(ethylene) and poly(propylene) with various disperse and fibre phases, including electrically-conducting polyaniline have been prepared. These composites were characterized by their conductivities as well as by employing optical and electron-scanning microscopy methods.
Composites based on a combination of ultra-high-molecular-weight poly(ethylene) with copper and graphite as secondary phases were found to possess conductivities below 10−7 S/m even at degrees of filling of 20 mass%. Composites containing up to 5 mass% carbon fibres or an equivalent combination with graphite had similar conductivity values. However, when the filler content exceeded the above-mentioned values there was a gradual increase in this parameter. Significantly better results were obtained when the polyaniline complex with dodecylbenzene sulfonic acid was introduced as the electrically conducting component. For example, the antistatic properties of composites based on ultra-high-molecular-weight poly(ethylene) or other polyolefins can be achieved at degrees of filling of 1.5 to 2 mass% with respect to the polyaniline component. Moreover, the conductivity values of the materials obtained in the molten state were, approximately, one to two orders of magnitude lower than those prepared by employing the in situ and wet paste methods. The results obtained from optical and electron-scanning microscopy indicate that, for polyaniline contents of ca. 2 mass%, fine particles of the conducting component were uniformly distributed within the thermoplastic polymer matrix. This contributed to the formation of a more sophisticated polymer network with a higher conductivity.