Effect of Corona Discharge Treatment on the Dyeability of Low-Density Polyethylene Film.

The effect of corona discharge on low-density polyethylene (LDPE) film was studied in terms of surface functionality and surface energetics of the film surfaces, improving the dyeability. The introduction of a polar group (O=C-O, C=O, and C-O) to a corona-treated LDPE film with acrylic acid could be confirmed by ESCA. The Owens-Wendt and Wu models using geometric means were studied to analyze the surface free energy of corona-treated film. It was found that the corona-treated LDPE film did lead to an increase in surface free energy, mainly due to the increase of its specific (or polar) component as the corona discharge power increased. Also, the K/S values were increased as the concentrations of dye increased. From the acid-base interaction point of view, it was found that the graft polymerization of acrylic acid onto the corona-treated LDPE film plays an important role in growing the acidic character which is one of the specific components of surface free energy, resulting in improving the dyeability with basic dyeing agent. A direct linear relationship is shown between the O(1s)/C(1s) ratio and the resulting K/S value or the specific component for this work. Copyright 2001 Academic Press.