This rather scientific information describes the roots of how Hydron Skin Care was created: Polyhydroxyethylmethacrylate From Wikipedia ( View original Wikipedia Article ) Last modified on 3 March 2013 at 15:10. "PHEMA" redirects here. For the Greek goddess, see Pheme. Polyhydroxyethylmethacrylate IUPAC name Poly(2-hydroxyethyl methacrylate) Other names PHEMA, Hydron Identifiers CAS number 25249-16-5 PubChem 24898472 Properties Molecular formula (C6H10O3)n Molar mass variable Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox references Poly(2-hydroxyethyl methacrylate) (pHEMA) is a polymer that forms a hydrogel in water. It was invented by Drahoslav Lim for use in soft contact lenses. Copolymers of pHEMA are still widely used today. Applications pHEMA functions as a hydrogel by rotating around its central carbon. In air, the non-polar methyl side turns outward, making the material brittle and easy to grind into the correct lens shape. In water, the polar hydroxyethyl side turns outward and the material becomes flexible. Pure pHEMA yields lenses that are too thick for sufficient oxygen to diffuse through, so all contact lenses that are pHEMA based are manufactured with copolymers that make the gel thinner and increase its water of hydration.[1] These copolymer hydrogel lenses are often suffixed "-filcon", such as Methafilcon, which is a copolymer of hydroxyethyl methacrylate and methyl methacrylate. References ^ Ratner, Buddy D. (2004). Biomaterials Science, An Introduction to Materials in Medicine. Elsevier Academic Press. ISBN 0-12-582463-7.
Posted on: Sat, 27 Jul 2013 09:10:16 +0000
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