Abstract:The starch ester film was prepared by solvent-casting method using Diethyl phthalate (DEP) as plasticizer. The changes in structure of the starch ester film and the intermolecular interaction between the molecule of DEP and starch ester were investigated by scanning electron microscope (SEM), attenuated total reflectance-fourier transform infrared spectroscopy (ATR-FTIR), and small-wide angel X-ray scattering (SAXS/WAXS). The results indicated that with the increase of DEP amount in the film, the inter- and intra-molecule interaction among the molecules of the starch ester was weakened and a greater amount of ordered microcrystalline structures was formed in the amorphous regions which resulted in the formation of more ordered aggregation microstructures. But the Rg of the microstructure remained 37~38 nm. Thus, intermolecular interaction, the order of molecular arrangement and aggregation structures of the starch ester can be controlled by adjusting the DEP content in the starch ester film, which provides fundamental data for the design of the starch-based materials with restrained plasticizer migration.
