Preparation and Characterisation of High-Density Polyethylene/Tannic Acid Composites.

This research paper highlights the preparation and characterisation of high-density polyethylene (HDPE)/tannic acid (TA) composites, designed to confer antioxidant properties to HDPE, valorising a biobased filler. Indeed, tannic acid is a natural polyphenol, demonstrating, among others, strong antioxidation properties. Using a melt-mixing process, HDPE/TA composites containing various amounts of TA, ranging between 1 and 20 wt%, were prepared, and analyses on their structural, thermal, mechanical, as well as antioxidant properties were conducted. Infrared spectroscopy, differential scanning calorimetry, and X-ray diffraction showed that TA was successfully incorporated into the HDPE matrix. Thermogravimetric analysis evidenced that the onset of thermal degradation decreased, but overall satisfactory stability was observed. The composites exhibited exceptional antioxidant properties, especially the ones with the highest TA content, although it was observed that a high amount of TA had adverse effects on the mechanical performance of the composites.