| 摘要 |
<p>Hydrophilic, crosslinked modified organopolysiloxanes are obtained from the polymerization of hydroxyalkylmethacrylate and/or hydroxyalkylacrylate in the presence of an organopolysiloxane which is soluble in the polymerizable monomer and has a molecular weight of at least 1,000, in which the organic groups of the organopolysiloxane are selected from the group consisting of hydrocarbon radicals, halogenated hydrocarbon radicals and mixtures thereof, said organopolysiloxane is crosslinked by condensation or by the addition of Si-bonded hydrogen to Si-bonded alkenyl groups, and containing at least 40 mol percent of monoorganosiloxane units. The amount and type of condensation catalyst and/or catalytic system, including the inhibitor for the polymerization of the hydroxyalkylmethacrylate and or hydroxyalkylacrylate in the polymerization process, is selected so that the crosslinking of the organopolysiloxane, which is substantially uniformly distributed in the hydroxyalkylmethacrylate and/or hydroxyalkylacylate, is initiated and preferably completed before the polymerization of the hydroxyalkylmethacrylate and/ or hydroxyalkylacrylate is complet ed. The modified organopolysiloxanes are more rigid than prior organopolysiloxanes. Thus, contact lenses made therefrom or containing such modified organopolysiloxanes enhance the correction of visual deficiencies which are attributable to a deformation of the cornea, for example, astigmatism.</p> |
