PERFLUOROPOLYETHER STRUCTURES AS SURFACE MODIFYING AGENTS OF UV-CURABLE SYSTEMS

New functionalised macromers containing perfluoropolyether (PFPE) stru ctures and methacrylic end groups were synthesised and used as modifyi ng additives for acrylic W-curable systems. Their chemical structure i s Rh-Rf-Rh, where [GRAPHICS] and Rf = -CF2O-(CF2-CF2-O)(p)(CF2-O)(q)CF 2- with p approximate to q. Notwithstanding their very low concentrati on, below 0.5 wt.-%, the fluorinated macromers cause a dramatic change of the surface properties of the films, without changing their curing conditions and their bull: properties. X-ray photoelectron spectrosco py (XPS) measurements showed that the macromers are able to concentrat e selectively at the surfaces of the films, depending on their chemica l structure and on the kind of substrate employed.