Barrier and Biodegradable Properties of Poly(butylene adipate-co-terephthalate) Reinforced with ZnO-Decorated Graphene Rendering it Antibacterial

In this paper, ZnO-decorated graphene (ZnO-graphene) was added to poly(butylene adipate-co-terephthalate) (PBAT) and maleic anhydride-grafted poly(butylene adipate-co-terephthalate) (PBAT-g-MAH) to prepare antibacterial nanocomposites through melt blending. The effect of different amounts of ZnO-graphene on the properties of the nanocomposite materials was discussed. The results of Fourier transform infrared (FTIR) analysis showed that PBAT-g-MAH could form coordination reaction and hydrogen bond with ZnO-graphene, and this synergistically enhanced the tensile properties of the nanocomposites. With the introduction of functional groups, the mechanical properties of PBAT-g-MAH/ZnO-graphene nanocomposites were significantly improved. Compared with pure PBAT, the nanocomposites showed that the maximum tensile strength, yield strength, and elongation at break increased by 20.58, 17.04, and 7.51%, respectively. This work revealed for the first time through X-ray diffraction tests the probable mechanism of dispersion or compatibility in the nanocomposites. Water absorption properties and water contact angle data proved that the introduction of MAH, along with the optimal amount of nanofillers, could greatly improve the tightness of internal and surface structures of the nanocomposites. Relative to PBAT, the use of PBAT-g-MAH/ZnO-graphene containing 0.6% nanofillers significantly improved the water vapor and oxygen barrier efficiencies by 152.8 and 273.5%, respectively. It was shown from the results of antibacterial evaluation that ZnO-graphene could impart PBAT and PBAT-g-MAH with excellent antibacterial activity. Compared with pure PBAT, the nanocomposite films had better mechanical and barrier properties. Both PBAT and PBAT-g-MAH nanocomposites could decompose naturally in soil, indicating that they were environmentally friendly and would have great application prospect in the fields of packaging and medical industries.