Preparation and characterization of starch film accompanied with ZnO nanoparticles

Biodegradable starch-zinc oxide films were made by casting starch film paste accompanied with ZnO nanoparticles. There was found a dissolving temperature of 60 degrees C, time of 30 min and the use of different amounts of oils, plasticizers, lubricants and binders presented a homogenous starch paste suitable for film casting to be prepared. X-ray diffraction, scanning electron microscopy and mechanical tests of the films showed a successful incorporation of ZnO nanoparticles into the starch matrix, and indicated the interactions between ZnO and starch. The starch-ZnO films showed an increase in tensile strength about 9.8366 MPa and elongation at break about 94% with 0.7 g nano ZnO, 0.3 g carboxyl methyl cellulose, 0.2 g oil and 1.5 g lubricant with 3 g starch. Moreover, this modified film had the antibacterial properties about 92% and 98% against S. aureus and Escherichia coli bacterial, respectively. Practical applicationsStarch films had good barrier properties to oxygen, carbon dioxide and lipids; while, they limited mechanical properties and water vapor resistance. In the existing study, this problem was overcome by being blended with ZnO nanoparticles and mechanical properties and water resistance increased. The developed films were in hydrophilic character when compared to conventional synthetic films such as PE and PP. Therefore, the advanced films are quite suitable to be used as a carrier polymer matrix for active hydrophilic and compounds in active food packaging applications. An additional potential application of those films existing in this study was used as edible film layer where mechanical and permeability resistance needed.