Electrical properties of recycled plastic nanocompsites produced by injection molding

Abstract

Plastic recycling is a recovery process of waste plastics to make new products into different forms. Plastics are usually sorted based on their resin identification codes before the recycling and melting processes. Although the recycling rate of plastics is significantly high, properties and economical value of the recycled plastics are fairly low, which in turn limits the use of recycled plastics in the market. In the present study, high density polyethylene (HDPE) in the form of pellets was dissolved in toluene, and then nanoscale graphene inclusions at different loadings (e.g., 0%, 0.25%, 0.5%, 1%, 2% and 4%) were added into the polymeric solutions. The remaining solvent was removed from the nanocomposite before the injection molding process. The injection molding process was conducted on the chopped recycled plastics associated with graphene loadings. The dielectric and electric properties of plastic nanocomposites were studied in detail. The test results showed that the dielectric properties were slightly improved by the addition of inclusions, which may be due to the non-polar nature of HDPE and/or residues in the recycled plastics. However, electrical conductivities of nanocomposites were significantly increased because of the improved electrical conduction, polarization and electron mobility at room temperature.