Effects of α-zirconium phosphate aspect ratio on the properties of polyvinyl alcohol nanocomposites

To study the effect of the aspect ratio (ratio of platelet length to thickness) of α-zirconium phosphate (α-ZrP) on the mechanical and thermal properties of polymer nanocomposites, polyvinyl alcohol (PVA)/α-zirconium phosphate (α-ZrP) nanocomposites with three distinctive aspect ratios at ca. 300, 590 and 1300 were prepared and characterized. Wide-angle X-ray diffraction (XRD), scanning electron microscopy (SEM), thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), dynamic mechanical (DMA) and tensile testing were utilized to characterise the film properties. As expected, it was found that the storage modulus, tensile strength (σb), elongation at break (ɛb) and decomposition temperature increased as the α-ZrP aspect ratio increased from 300 to 590. However, when the aspect ratio reached 1300, the enormously enlarged specific surface area of α-ZrP resulted in strong aggregation of the nanolayers which resulted in severe deterioration of the film properties.