posted on 2016-10-04, 00:00authored byGopi Krishna Tummala, Thomas Joffre, Viviana
R. Lopes, Aneta Liszka, Oleksiy Buznyk, Natalia Ferraz, Cecilia Persson, May Griffith, Albert Mihranyan
A nanocellulose-reinforced
poly(vinyl alcohol) hydrogel material
of exceptionally high water content for ophthalmic applications is
presented (>90 wt %), which also features a hitherto unprecedented
combination of optical, mechanical, viscoelastic, oxygen permeability,
and biocompatibility properties. The hydrogel combines the desired
softness with remarkable strain-dependent mechanical strength and
thereby demonstrates hyperelastic, rubber-like mechanical properties.
The observed unusual mechanical behavior is due to both high water
content and the combination of relatively stiff cellulose nanowhiskers
entangled in a soft polymer matrix of poly(vinyl alcohol) (PVA), thus
mimicking the structural characteristics of the cornea’s main
constituents, i.e., water and collagen.