ISSN:
0021-8995
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
Methacrylate end-capped diethylene glycol propyl methyl ether, 5-hexyl-1,2-diol, and 3-propyloxy-1,2-propane diol side-chain siloxanes were evaluated for potential use as hydrogels for contact lens application. The preparation of the methacrylate end-capped ether, hexane diol, and propane diol side-chain siloxanes was accomplished in two relatively simple synthetic steps: The first step consisted of the acid-catalyzed co-ring opening polymerization of octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, and 1-3-bis-methacryloyl-butyltetramethyldisiloxane, followed by a platinum-catalyzed hydrosilation with (in separate experiments) diethylene glycol allyl methyl ether, trimethylsilyl protected 3-allyloxy-1,2-propane diol, and trimethylsilyl protected 5-hexene-1,2-diol. The trimethylsilyl protecting groups was removed using a 10% 0.1N HCl solution in 2-propanol. Radical polymerization of the methacrylate end-capped ether, hexane, and propane diol side-chain siloxanes with hydrophilic monomers, such as dimethylacrylamide, and a strengthening agent, isobornylmethacrylate, resulted in transparent hydrogels possessing a wide range of water contents, high oxygen permeability, and a low modulus of elasticity and, for the propane diol side-chain siloxanes, excellent hydrolytic stability. The ether side-chain siloxane-based hydrogels exhibited poor hydrolytic stability. © 1995 John Wiley & Sons, Inc.
Additional Material:
2 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/app.1995.070550408
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