25 KB231 KB19 KB200020242011Vesel, Alenkaštevilka:3letnik:45str. 217-220ISSN:1580-2949COBISSID:858794URN:URN:NBN:SI:doc-KZH9TZTAenInštitut za kovinske materiale in tehnologijeMateriali in tehnologijefluorinacijahidrofobizacijaplazmapolistirenpovršinska funkcionalizacijarentgenska fotoelektronska spektroskopijaHydrophobization of polymer polystyrene in fluorine plasma| Hidrofobizacija polimera polistiren s fluorovo plazmo|Modification of surface properties of polymers by plasma fluorination was studied by X-ray Photoelectron Spectroscopy (XPS). Samples of polystyrene (PS) were exposed to weakly ionized reactive gaseous plasma created in tetrafluormethane (CF4) gas. Reactive plasma particles rapidly interacted with the samples forming a surface film rich with CFx functional groups. The appearance of these groups was monitored by high-resolution XPS, while the resultant modification of surface properties was monitored by water drop contact angle technique. Survey XPS spectra showed a substantial concentration of over mole fraction 50 % of fluorine, while high resolution C1s spectra revealed the appearance of different functional groups. The CF2 group was predominant as approximately a third of carbon atoms was found in this group. The contact angle measurement revealed simultaneous modification of the surface free energy from moderately hydrophobic original material to highly hydrophobic state, as the water contact angle increased from original 85° to 111°. Plasma fluorination is therefore a suitable method for improving of surface properties of polymers for biomedical applicationsZ metodo rentgenske fotoelektronske spektroskopije (XPS) smo preiskovali spremembe v površinski sestavi polimerov pri plazemski fluorinaciji. Vzorce polistirena (PS) smo izpostavili šibko ionizirani reaktivni plinski plazmi, ustvarjeni v fluorometanu (CF4). Reaktivni delci iz plazme so izredno hitro reagirali s površino vzorca, zaradi česar je nastala tanka površinska plast, bogata s CFx-skupinami, kar je povzročilo spremembo omočljivosti vzorca. Nastanek teh skupin smo dokazali z metodo XPS, medtem ko smo spremembo omočljivosti določali s kontaktnim kotom vodne kapljice. Iz preglednih XPS spektrov je razvidna znatna koncentracija fluora na površini vzorca z molskim deležem večjim od 50 %. Iz visoko ločljivih spektrov ogljika smo določili različne fluorove funkcionalne skupine, med katerimi je največji delež, skoraj eno tretjino, zavzemala skupina CF2. Z merjenjem kontaktnega kota smo ugotovili porast hidrofobnosti površine, saj je kontaktni kot narasel iz začetnih 85° na 111°. Rezultati so pokazali, da je plazemska fluorinacija primerna metoda za izboljšanje površinskih lastnosti polimerov za biomedicinske aplikacije, kjer želimo imeti čim bolj inertno površinoTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaInštitut za kovinske materiale in tehnologije