Preparation and characterization of natural corn starch-based composite films reinforced by eggshell powder

The aim of this work is to study the effect of eggshell powder (ESP) on the properties of corn starch (CS) films. It was found that the addition of ESP significantly improved the tensile strength, elongation at break, water vapor and oxygen barrier properties compared to the control film. There was an inductive effect between the C–C bonds on cornstarch skeleton and the O–C–O bond on CaCO3 in the ESP and the number of hydrogen bands increased between starch molecules and ESP particles, which indicated a strong interaction and biocompatibility between the two components. In addition, the organic compounds on the surface of ESP increased the adhesion between CaCO3 particles and CS films matrix. In summary, the ESP, as an enhancement factor, is a good candidate for the development of green food packaging material.