Initial stages in surface functionalization of polymers by plasma radicals (J2-1728)

Project leader: Prof. Dr Manja Kurečič (University of Maribor, Faculty of Electrical Engineering and Computer Science)

Investigator: Prof. Dr Janez Kovač (Jozef Stefan Institute)

Initial stages of polymer functionalization with different functional groups will be determined experimentally. Results will represent a breakthrough in understanding the complex mechanism involved at interaction of reactive gaseous species with polymer surfaces. For the first time, the polymer surfaces will be exposed to variable fluences or reactive plasma radicals and the evolution of various functional groups with increasing fluences will be determined without breaking vacuum conditions using our high-resolution XPS instrument. The fluences will be measured precisely using specially adopted laser-driven catalytic probes. The evolution of functional groups versus fluences will be determined separately for oxygen and fluorine atoms as well as NHx radicals. The sources of these species will be microwave-driven discharges at variable powers. Three sources will be mounted onto the treatment chamber employing oxygen, ammonia and tetrafluoromethane as working gases. Gases will be introduced into the discharge chambers through flow controllers and will dissociate to radicals upon plasma conditions. The radicals will then enter the processing chamber which will be pumped continuously to assure for a rapid transfer of radicals from the plasma region to the samples with reasonable loss due to recombination or association to parent molecules. The entire experimental setup will be UHV compatible so the concentration of gaseous impurities will be marginal. The project will employ experts in polymer and plasma science as well as experts in construction of custom-designed plasma systems, high-frequency plasma sources and surface characterization. The results will be published in reputable topical journals and we shall also write a monography on initial stages of polymer functionalization. Such a monography is currently not available since no group worldwide has performed experiments foreseen within this project. The dissemination will be through scientific meetings and media.