INLUENCE OF REPROCESSING CYCLES BY INJECTION ON THE PHYSICAL CHARACTERISTICS OF WASTE FROM OXYBIODEGRADABLE AND CONVENTIONAL BAGS

Abstract

Plastic bags, typically made of high-density polyethylene (HDPE), are items that are still widely used in everyday life and unfortunately have a short useful life and end up generating large amounts of waste. The scenario worsens when there is no collection and proper disposal of this waste. Pro-degrading additives composed of transition metal salts appear as an alternative to reduce the impact caused by the inappropriate disposal of plastic bags. However, the use of these additives facilitates the degradation of the polymer, which can be a negative factor for the recycling chain. The present study evaluated the influence of pro-degrading additives in the process of recycling bags by injection, comparing the optical and mechanical characteristics of the sample produced. A darkening of both samples was noticed, however the samples derived from the bags containing the additive showed loss of brightness and a slight yellowing, indicating the possible initiation of degradation. Typical behaviors of HDPE recycling were evident, such as increased impact resistance and traction due to crosslinking of the polymeric matrix. Finally, it was not possible to observe negative effects of the presence of pro-degrading additives on the mechanical characteristics and in the process of recycling HDPE by injection.