title: Studying functional properties of hydrogel and silicone-hydrogel contact lenses with PALS, MIR and Raman spectroscopy.
abstract: Determination of free volume holes of the hydrogel and silicone-hydrogel polymer contact lenses were investigated. Two types of polymer contact lenses were used as materials: the first is a hydrogel contact lenses Proclear family (Omafilcon A), while the second is a silicone-hydrogel contact lens of the family Biofinity (Comfilcon A). Positron annihilation lifetime spectroscopy PALS was used to characterize geometrical sizes and fraction of the free volume holes in the investigated samples. There is a clear difference in the free volume sizes and their fractions between silicone-hydrogel and polymer hydrogel contact lenses which in turn are connected with oxygen permeability in these lenses. Apart from that, spectroscopic (middle infrared) MIR and Raman examinations were carried out in order to demonstrate the differences of the water content in the test contact lenses.
authors.affiliation: Institute of Physics, Jan Dlugosz University, Al. Armii Krajowej 13/15, 42-200 Czestochowa, Poland. Electronic address: j.filipecki@ajd.czest.pl.
authors.forename: J
authors.initials: J
authors.lastname: Filipecki
authors.affiliation: AGH University of Science and Technology, Faculty of Materials Science and Ceramics, Al. Mickiewicza 30, 30-059 Cracow, Poland.
authors.forename: M
authors.initials: M
authors.lastname: Sitarz
authors.affiliation: Institute of Physics, Jan Dlugosz University, Al. Armii Krajowej 13/15, 42-200 Czestochowa, Poland.
authors.forename: A
authors.initials: A
authors.lastname: Kocela
authors.affiliation: AGH University of Science and Technology, Faculty of Materials Science and Ceramics, Al. Mickiewicza 30, 30-059 Cracow, Poland.
authors.forename: K
authors.initials: K
authors.lastname: Kotynia
authors.affiliation: AGH University of Science and Technology, Faculty of Materials Science and Ceramics, Al. Mickiewicza 30, 30-059 Cracow, Poland.
authors.forename: P
authors.initials: P
authors.lastname: Jelen
authors.affiliation: Institute of Physics, Czestochowa University of Technology, Al. Armii Krajowej 19, 42-200 Czestochowa, Poland.
authors.forename: K
authors.initials: K
authors.lastname: Filipecka
authors.affiliation: AGH University of Science and Technology, Faculty of Materials Science and Ceramics, Al. Mickiewicza 30, 30-059 Cracow, Poland.
authors.forename: M
authors.initials: M
authors.lastname: Gaweda
mesh_terms: D003261:Contact Lenses; D004583:Electrons; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000737:chemistry*; D008422:Materials Testing; D011108:Polymers / Q000737:chemistry; D016062:Porosity; D012828:Silicones / Q000737:chemistry*; D013055:Spectrophotometry, Infrared; D013059:Spectrum Analysis, Raman
chemical_list: D011108:Polymers; D012828:Silicones; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate
keywords: Contact lenses; Free volume; MIR; Polymers; Positron annihilation; Raman spectroscopy