Analysis of free volumes and light transmission in hydrogel and silicone-hydrogel polymer contact lenses
نویسندگان
چکیده
The free volume holes and light transmission of hydrogel and silicone-hydrogel polymer contact lenses were investigated. As the material, the Proclear family (omafilcon A) of hydrogel contact lenses and the Biofinity family (comfilcon A) of silicone-hydrogel contact lenses were used. Positron annihilation lifetime spectroscopy was used to characterize geometrical sizes and fractions of the free volume holes in the investigated samples. There was a clear difference in the size of free volume holes and the fractional free volume between silicone-hydrogel and hydrogel polymer contact lenses. These changes are shown by a thorough analysis of the long-lived component of lifetime of ortho-positronium. At the same time, UV-vis-NIR in the spectral range 200–1000 nm studies were performed on the same samples of contact lenses spectrometry.
منابع مشابه
Investigation of the Degree of Disorder of the Structure of Polymer Soft Contact Lenses Using Positron Annihilation Lifetime Spectroscopy PALS.
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