Water plasticized high refractive index polymer for ophthalmic applications
A high refractive index, foldable polymer suitable for use in ophthalmic devices, such as intraocular lenses, is provided. The polymer may be produced from a polymerization reaction of first, second and third monomeric components and a crosslinking agent. The first monomeric component includes an aryl acrylate or an aryl methacrylate. The second monomeric component, which is not an acrylate, includes a monomer having an aromatic ring with a substituent having at least one site of ethylenic unsaturation. The third monomeric component includes a high water content hydrogel-forming monomer. The resulting high refractive index copolymer is durable enough to be cut and polished when dry, and becomes soft and foldable when hydrated.
1. A method of manufacturing an intraocular lens, the method comprising:
a) a first monomeric component which comprises an aryl acrylate or an aryl methacrylate;
a second monomeric component which comprises a monomer having an aromatic ring with a substituent having at least one site of ethylenic unsaturation, wherein the second monomeric component is other than an acrylate; and,
a third monomeric component which comprises a high water content hydrogel-forming monomer, wherein:
the copolymer has a glass transition temperature greater than about normal room temperature;
b) forming a rigid intraocular lens having the desired dimensions from the copolymer; and
c) hydrating the copolymer to from a foldable, hydrated intraocular lens; wherein:
hydrating the copolymer comprises
placing the copolymer in an aqueous solution;
gradually increasing the temperature of the aqueous solution to about 40° C.,
holding the temperature of the aqueous solution at about 40° C. for at least about 10 minutes;
gradually increasing the temperature of the aqueous solution to about 60° C.;
holding the temperature of the aqueous solution at about 60° C. for at least about an hour; and,
gradually decreasing the temperature of the aqueous solution to about room temperature.