Blends of poly(ethylene terephthalate) and low density polyethylene containing aluminium: A material obtained from packaging recycling



Composites of polyethylene and aluminium (PEAL) may be obtained from the recycling of postconsumed Tetra Pak aseptic packaging. The components of the composite are low density polyethylene (LDPE), aluminium and an ethylene-methacrylic acid random copolymer (EMAA). The presence of metallic filler and a functionalized copolymer, which may act as a compatibilizer, suggests that blending PEAL with other thermoplastic would be a way to obtain reinforced and compatibilized blends from recycled materials. Blends of PEAL and recycled poly(ethylene terephthalate) (PET) were prepared in the compositions of 30, 50, and 70 wt % of PET in a twin-screw extruder. Blends of PET/LDPE and PET/EMAA were also prepared for comparison. The morphological analysis showed that the PET/PEAL blends present an excellent interfacial adhesion, similar to the PET/EMAA blend. The improvement of adhesion in comparison with the PET/LDPE blend is a result of the interaction between polar groups of PET and EMAA. PET/PEAL blends presented lower elongation at break and impact strength than the other blends whereas Young modulus was higher. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007