Structure and properties of starch/α-zirconium phosphate nanocomposite films

Glycerol-plasticized pea starch/α-zirconium phosphate (PS/ZrP) nanocomposite films with different loading levels of α-zirconium phosphate (α-ZrP) were prepared by a casting and solvent evaporation method. The effects of the α-ZrP on the structure and properties of the PS/ZrP films were characterized by Fourier transform infrared (FT-IR) spectroscopy, wide-angle X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and tensile testing. The results indicated that hydrogen bonds formed between pea starch (PS) and α-ZrP, which improved the compatibility between PS and α-ZrP. Compared with the neat PS, the tensile strength (σb) and elongation at break (εb) of the PS/ZrP nanocomposite films were significantly enhanced with an increase in α-ZrP content. The maximum values of σb and εb reached 9.44 MPa and 47.5%, respectively, at 0.3% α-ZrP and 25% glycerol as plasticizer. The moisture uptake of the nanocomposite films, measured in an environment with 92% relative humidity, was reduced by the addition of α-ZrP. The structure and properties of pea starch-based films were modified and improved by the incorporation of α-ZrP.