Poly(butylene adipate-co-terephthalate)/Graphene Oxide Nanocomposite Films for Food Packaging Applications

Poly(butylene adipate-co-terephthalate) (PBAT) and graphene oxide (GO) nanocomposite films were prepared by extrusion to evaluate their potential as films for food packaging. The films were prepared with contents of 0.05, 0.1, and 0.25% in mass of GO by solid–solid deposition methodology. It was verified that GO did not modify the hydrophobicity and crystallinity degree of PBAT. The reduction of molecular weight due to GO incorporation was verified, and it could be the main reason for the observed decrease in tensile strength and increase in elongation. The nanofiller permitted ultraviolet blocking, thermal stability, and oxygen barrier improvements without compromising film visibility. Compared to the neat PBAT film, the oxygen permeability coefficient was reduced by 13.6% for PBAT/GO0.25. The elongation and tenacity were also improved by 90% and 33%, respectively, for the highest concentration of GO (0.25%). Besides, GO at 0.25% accelerated the mineralization rate of PBAT in soil, probably due to the lower molecular weight of nanocomposites in relation to the neat polymer. The preliminary information obtained in this work indicates that the level of PBAT hydrolytic degradation during the extrusion process was not high enough to avoid its application in food packaging because the obtained thermal, mechanical, and ultraviolet (UV) barriers still indicate an exciting balance of properties for this purpose, which can even be improved with future research.