화학공학소재연구정보센터
Thin Solid Films, Vol.338, No.1-2, 291-299, 1999
Effects of photo-excitation and organic vapor treatment on vapor sorption behavior of sputtered fluoropolymer films
Investigation of sorption capacities for volatile organic compounds of radio-frequency-sputtered fluoropolymer films has revealed that they are affected by the applied voltage and by supplemental photo-excitation using ultraviolet light irradiation during sputtering. The photoassisted effects of producing unsaturated carbons on the sputtered tetrafluoroethylene film are revealed by infrared, electron spin resonance, and X-ray photoelectron spectroscopies. Measurements of sorption capacities and computational chemical calculation for six-membered cyclic hydrocarbons revealed that the pi-character of the solute molecule is a decisive molecular descriptor for sorption behavior of the sputtered fluoropolymers. The pi-character of the sputtered fluoropolymer films can be enhanced by a photo-assisted effect, which can also increase the affinities for pi-characterized solutes by pi-pi interaction. This is further clarified by the fact that the photo-assisted fluoropolymer film has a larger sorption capacity for highly pi-conjugated double aromatic ring systems (C10H8): naphthalene than for slightly pi-conjugated, but polar, isomer: azulene. It was also found that saturated organic vapor (p-xylene and 2-butanone) sorption can enhance the sorption capacities of the sputtered fluoropolymer by restructuring induced by solvation and radical reaction.