Abstract: Starch nanocrystals (SN) was prepared by sulfuric acid hydrolysis with waxy maize starch as the starting material and polyvinyl alcohol (PVA)/SN nanocomposite films were prepared by solution casting method. The effect of SN on the structure and properties of the PVA/SN composite films was studied. The characterization results showed that SN was composed of nano particles as disk shape with an average diameter around 30~60 nm. With the increase of SN in the composite films, both mechanical properties and barrier performance firstly increased and then decreased. When the content of SN increased to 10 %, the tensile strength of the composite film reached 54 MPa from 47 MPa of neat PVA film. In addition, the gas permeability of the composite films also decreased 70 % compared with the neat film.

Key words: polyvinyl alcohol, starch nanocrystals, mechanical property , barrier property