Nanomaterials are often introduced to improve the properties of polymers. In this article, the effects of SiO2 nanoparticles
with lager specific areas and special microstructural characters on the properties of starch films were investigated. Firstly,
the ultrasonic mixing was used to disperse the SiO2 nanoparticles under different dispersion times, and then the dispersed SiO2nanoparticles with various ratios were added into starch size. The effects of the dispersion time and the SiO2 content on the mechanical properties of the SiO2/starch composite size were analysed. It was found that the dispersion time and the SiO2 content had significant effects on the tensile and abrasion behaviour of the nanocomposite films. The mechanism of the enhanced mechanical properties of the composite films was examined by analysing the size of the dispersed SiO2 nanoparticles in the dispersion, the surface characters of the films and the structures of the fractured surfaces. And the morphology of the abraded surface was analysed by atomic force microscopy, scanning electron microscope and video zoom microscope.