US 4,954,587 AGranted

Dimethylacrylamide-copolymer hydrogels with high oxygen permeability

AssigneeCiba-Geigy Corporation

InventorKarl F. Mueller

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Abstract

This invention describes polymers which are obtained by copolymerization of 15-85 wt % N,N-dimethylacrylamide with about 15-85% of a fluorinated monomer such as perfluoroalkyl-alkylene acrylate or methacrylate with from 3 to 25 fluorine atoms and optionally, 0-50 wt % other acrylates or methacrylates and 0-20 wt %, but not more than 5 mol % of a polyvinyl functional crosslinking agent. These polymers are machinable in the dry state and form clear hydrogels with about 25-75 wt % water content and which possess oxygen-permeabilities 3-7 times higher than conventional hydrogels of similar water content. In the absence of crosslinking, the novel polymers are plasticized by water, forming clear hydroplastics with 30-70 wt % water content. The crosslinked polymers are especially useful for fabricating contact lenses for extended wear by either cutting and polishing a xerogel button, or by spin casting or direct molding in bulk or in solution.

Claims12

Dependent claims

A copolymer, having the characteristics of high clarity, high hydrophilicity, and high oxygen permeability and which is, in the water swollen hydrated state, soft and flexible, which copolymer comprises the polymerization product of, with weight percent based on the total weight of monomers (a), (b), (c) and (d), of

(a) 24.9 to 70 percent by weight of N,N-dimethylacrylamide,
(b) 65 to 19.9 percent by weight of a vinyl monomer selected from the group consisting of the acrylate or methacrylate esters of formula B1 ##STR5## wherein R.sub.1 is hydrogen or methyl,
n is an integer from 1-4,
m is an integer from 0-11,
X is hydrogen or fluorine, with the proviso that, when m is 0, X is fluorine;
and hexafluoroisopropyl methacrylate,
(c) 10 to 40 percent by weight of a C.sub.2 -C.sub.4 -hydroxyalkyl acrylate or methacrylate, a C.sub.2 -C.sub.4 -alkoxy-alkyl acrylate or methacrylate or an oligosiloxanyl-silylalkyl acrylate or methacrylate containing 2 to 10 silicon atoms, or mixture thereof, and
(d) 0.1 to 3 percent by weight of a crosslinking agent having at least two copolymerizable vinyl groups.

5 more elements

Dependencies are inferred from the claim text.

Facts

Application: 07/356,801Filed 23 May 1989 · continuation in part
Priority: 5 Jul 1988
Granted: 4 Sep 1990
Term ends: Not estimatedThe source records don’t support an estimate.

Classification10 codes

C08F 220/54
Amides or imides: amides , e.g. N,N-dimethylacrylamide or N-isopropylacrylamide
A61L 26/0014
Containing macromolecular materials: obtained by reactions only involving carbon-to-carbon unsaturated bonds
A61L 26/008
Use of materials characterised by their function or physical properties: hydrogels or hydrocolloids
A61L 27/16
Macromolecular materials: obtained by reactions only involving carbon-to-carbon unsaturated bonds