Comparison of some effects of modification of a polylactide surface layer by chemical, plasma, and laser methods

Abstract

The article presents the results of studies and comparison of selected properties of the modified PLA surface layer. The modification was carried out with three methods. In the chemical method, a 0.25M solution of sodium hydroxide in water and ethanol was utilized. In the plasma method, a 50W generator was used, which produced plasma in the air atmosphere under reduced pressure. In the laser method, a pulsed ArF excimer laser with fluency of 60mJ/cm2 was applied. Polylactide samples were examined by using the following techniques: scanning electron microscopy (SEM), atomic force microscopy (AFM), goniometry and X-ray photoelectron spectroscopy (XPS). Images of surfaces of the modified samples were recorded, contact angles were measured, and surface free energy was calculated. Qualitative and quantitative analyses of chemical composition of the PLA surface layer were performed as well. Based on the survey it was found that the best modification results are obtained using the plasma method.