Phase Morphology and Performance of Supertough PLA/EMA-GMA/ZrP Nanocomposites Prepared through Reactive Melt-Blending.

Nanofiller zirconium phosphate (ZrP) and ethylene-methyl acrylate-glycidyl methacrylate copolymer (EMA-GMA) were introduced into poly(lactic acid) (PLA) through reactive melt-blending method to improve its toughness. The impact strength of PLA/EMA-GMA/ZrP (82/15/3) nanocomposites was improved about 22 times that of pure PLA to 65.5 kJ/m. Fourier transform infrared spectroscopy (FTIR) analysis indicated there were compatibilization reactions between the components. The miscibility and thermal behavior of the blends were investigated by dynamic mechanical analysis (DMA), differential scanning calorimetric (DSC), and thermogravimetric analysis (TGA). Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were applied to observe the fractured surface and phase morphology to study the toughness mechanism. A typical core-shell morphology, ZrP wrapped by EMA-GMA phase, was observed in the nanocomposites, which can cause plastic deformations. The supertough effect of the compound was mainly confirmed by effective interfacial compatibilization and massive shear-yielding deformation achieved by the synergy of EMA-GMA with ZrP in the PLA matrix.