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%,，透氧率為5.8×10-6 cm3/(m2?d?Pa)。The film forming solution based on corn anionic starch was treated with ultrasonic and the tensile strength, elongation and oxygen permeability were analyzed. Ultrasonic treatment could destroy the structure of the starch grain, shorten the molecule chain, and increase the amylase content. It could also expose out more polar groups, break hydrogen bonds and hydrophobic combining poles inside liquid, and make macromolecule to recombine into non-polar bonds. Under the appropriate treatment power and time, the film could get better mechanical and barrier properties, that is, at 80 W and 50 min, tensile strength of the film is 25.53 MPa, elongation is 29.07%, and oxygen permeability is 5.8×10-6 cm3/(m2?d?Pa), the surface homogeneity has been improved. 