Preparation of Graphene-Modified PLA/PBAT Composite Monofilaments and Its Degradation Behavior

The graphene-modified composite poly(lactic acid) (PLA)/poly(butylene adipate-co-terephthalate) (PBAT) monofilaments were prepared by melt spinning. The effects of graphene (GR) contents on the microstructural, thermal, dynamic mechanical, and mechanical properties and the degradation behavior of the graphene-modified composite PLA/PBAT monofilaments were studied. Scanning electron microscopy (SEM) confirmed the improved compatibility of the PLA particles in the PBAT matrix, while the transmission electron microscopy (TEM) demonstrated the size and morphology of the GR distribution in the polymer. As the GR content increased, dynamic mechanical analysis (DMA) clarified a decrease of the difference of glass transition temperature (Tg) between PLA and PBAT. In addition, the mechanical properties of the composite monofilaments were significantly enhanced at a GR content of 0.2 wt%. Weight loss rate of the composite monofilaments under soil and sea degradation conditions were obviously related to the GR content.