| 摘要 |
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. |
