Thermal, chemical and mechanical property evaluation of recycled-reprocessed high density polyethylene

Plastic recycling was carried out on the virgin HDPE, collected recycled HDPE material, and the mixture of both. Processing aids in terms of certain percentages of anti-oxidants and slipping agents were added to virgin HDPE and the 50/50 mixture of fresh HDPE and recycled HDPE material. The specific emphasis was placed on the thermooxidative degradation of material during processing cycle. The performance of resulting reprocessed plastics was monitored using Fourier transform infra-red (FTIR), differential scanning calorimeter (DSC), and study of mechanical properties. The results clearly reveal the rapid thermooxidative degradation of the 50/50 mixture of fresh and recycled HDPE material, which can be attributed to the antagonistic mixing effect of two materials and the early loss of added anti-oxidants and processing stabilizers. The better processing stability can be achieved by incorporating appropriate percentages of processing stabilizers in the polymer resin.