Abstract
The oxygen permeability of several polymeric materials used for hard and soft contact lens applications was determined using a gas-to-water oxygen permeation technique. The technique measures oxygen permeation through polymeric films kept between a gaseous and an aqueous phase at 34°C, where the oxygen is dissolved and measured with an oxygen analyzer. Oxygen permeabilities were measured for poly(methyl methacrylate), cellulose acetate butyrate, a blend of PMMA and CAB with silicone networks, poly (hydroxyethyl methacrylate) hydrogels, and a series of amorphous and semicrystalline poly (vinyl alcohol) hydrogels. Dissolved oxygen permeabilities ranging from 0.155 x 10 −10 cm 3(STP)·cm/sec·cm 2·cmHg for PMMA to 78.95 x 10 −10 cm 3(STP)·cm/sec·cm 2·cmHg for an amorphous PVA membrane with degree of hydration of H = 0.866 were observed. For amorphous hydrogels, the oxygen permeability is a function of thickness and degree of hydration. Boundary layer effects and the effect of structural characteristics of the polymer on the permeability coefficients are discussed.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.