Submitted to: Journal of Applied Polymer Science
Publication Type: Peer reviewed journal
Publication Acceptance Date: 10/17/2007
Publication Date: 6/2/2008
Citation: Patil, D.R., Fanta, G.F., Felker, F.C., Salch, J. 2008. Application of Hydrophilic Starch-based Coatings to Polyethylene Surfaces. Journal of Applied Polymer Science. 108(5):2749-2755. Interpretive Summary: Water-compatible coatings on plastic film surfaces helps to reduce static buildup, alters friction and adhesion properties, improves the absorption of water-based dyes and inks, and enhances the compatibility of the film with body fluids. Formulations that could be easily sprayed onto plastic surfaces were prepared by combining jet cooked dispersions of starch with water-based epoxy resin, wax emulsion and surfactant. Heating the coated film produced a coating that became uniformly wet when the film was placed in water and did not separate from the film surface. Improved adhesion of the coating was observed when a resin was added to react with starch to make it less dispersible in water.
Technical Abstract: Coatings were applied to polyethylene film surfaces by spraying formulations prepared from a jet cooked dispersion of waxy cornstarch, a water-based epoxy resin, a wax emulsion, and a surfactant. Although the starch component separated rapidly from the coating when the film was placed in water at room temperature, heating the coated film for 24 h at 80 deg C increased the adhesion of starch and produced a surface coating that remained uniformly wet when the film was placed in water. Most of the starch, however, could still be removed by gently rubbing the wet surface. If melamine-formaldehyde resin was added to the formulation to crosslink the starch, and the coated film was then heated for 24 h at 80 deg C, most of the starch remained bonded to the wet coating, even after the surface was gently rubbed.