Abstract:Hydrophobic esterified starch-based films with different structures were prepared by using esterified starches with different ratios of amylose and amylopectin, and the inhibitory effect of these structures on migration of the plasticizer diethyl phthalate (DEP) during microwave treatment was investigated. The results indicated that the waxy esterified starch-based film (waxy ES) with an amylose and amylopectin ratio of zero exhibited a strong molecular interaction, a large ordered aggregation region, and the strongest inhibitory effect on DEP migration. For the esterified starch-based film (G50 ES) with an amylose and amylopectin ratio of 50%, despite weak molecular interaction, the large ordered aggregation region and the compact internal structure impeded the movement of DEP molecules effectively. For the esterified starch-based film (G80 ES) with an amylose and amylopectin ratio of 80%, despite the presence of microcrystals, the molecular interaction was weak, the size of ordered aggregation region was small, and the highest amount of DEP migrated. Therefore, plasticizer migration can be reduced by controlling the amylose/amylopectin ratio in esterified starch-based film. These results provide the basic data and theoretical basis for a more reasonable design and safe application of starch-based film as packaging materials.
