Ricerc@Sapienza

High-density polyethylene (HDPE) and poly(lactic) acid (PLA) blends with different ratios of both polymers, namely, 30:70, 50:50, and 70:30, were produced. Polyethylene-grafted maleic anhydride and a random copolymer of ethylene and glycidyl methacrylate were also considered as compatibilizers to modify HDPE/PLA optimal blends and were added in the amounts of 1, 3, and 5 wt.%. Different properties of the blends were evaluated by performing tensile tests and scanning electron microscopy to analyze blend and interfaces morphology.

Oil-based/bio-derived blends have been produced with high-density polyethylene (HDPE) and Soy Protein Isolate (SPI). In order to be processed, SPI is plasticized with glycerol. In order to overcome different hydrophilicity between natural and oil-based polymers, a compatibilizer has been introduced. Polyethylene-graft-glycidyl methacrylate (PE-g-GMA) has been selected to act on HDPE-SPI interface. Good effect of PE-g-GMA has been displayed, increasing tensile strength, keeping almost the same elastic modulus and elongation at break.

Blends based on high density polyethylene (HDPE) and poly(lactic) acid (PLA) with different ratios of both polymers were produced: a blend with equal amounts of HDPE and PLA, hence 50 wt.% each, proved to be a useful compromise, allowing a high amount of bio-derived charge without this being too detrimental for mechanical properties and considering its possibility to biodegradation behaviour in outdoor application.