Surface Hardness Improvement of PMMA by Low-Energy Ion Irradiation and Electron Irradiation

摘要

Surface modification of PMMA (polymethyl-methacrylate) was carried out by irradiation with low-energy ions and/or electrons, which is expected to improve the surface hardness by introduction of a thin modified layer. The surface hardness was measured by the nanoin-dentation test. To clarify the structure and the properties of the modified layer, depth profiles of composition and chemical bonds were analyzed using XPS (X-ray photo-electron spectroscopy). The formation of a cross-linking structure that contributed to the surface hardness was analyzed by the dyeing method. From these results, it was confirmed that the surface hardness increased and a cross-linking structure was present. It is suggested that the existence of the structure brought about the increase of surface hardness, showing the utility of the dyeing method.