Fluorocarbon Barriers on Starch Foam Tray Surfaces Through SF6 Cold Plasma Treatment

Starch foam trays were produced using a laboratory model-baking machine. Surfaces of the trays were treated with SF₆ plasma to create fluorine-rich layers on the surfaces. RF power, gas pressure and reaction time were varied to evaluate the effects of each parameter on fluorination of surfaces. The fluorine concentrations of treated sample surfaces ranged from 43.6% to 57.9%. For reaction time dependence, the ratio of oxygen to carbon was decreased since hydroxyl groups might be replaced by fluoro-compounds. Gas pressure and RF power affected fluorination mechanism, which resulted in different shapes of carbon and fluorine ESCA high resolution spectra. Plasma-treated samples have higher contact angles and less uptakes of liquid and vapor water. AFM showed different morphology of untreated and SF₆ plasma-treated surfaces.