Biocompatible polyurea-urethane hydrated polymers
AssigneeW. R. Grace & Co.-Conn.
InventorsJames A. Braatz, Clifton L. Kehr
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Abstract
A class of hydrophilic prepolymers and hydrated polymer gels are disclosed which are characterized by their transparency, biocompatibility and resistance to nonspecific protein adsorption. At least 75%, preferably at least 90%, of the prepolymers are isocyanate-capped oxyethylene-based diols or polyols having molecular weight of about 7000-30,000. Essentially all of the hydroxyl groups of the diols or polyols are capped with polyisocyanate prior to formation of the hydrated polymer.
Claims31
A hydrophilic, biocompatible hydrated polyurea-urethane polymer gel derived from prepolymer units having an isocyanate concentration of no more than 0.46 meq/gm and at least 75% of which are oxyethylene-based diols or polyols having an average molecular weight of about 7000 to about 30,000, said diols or polyols having essentially all of the hydroxyl groups capped with polyisocyanate, said hydrated polymer gel characterized by transparency and by a surface which resists nonspecific protein adsorption and formed by reacting said prepolymer units with water;
- said polyisocyanate being an aliphatic or cycloaliphatic isocyanate.
A crosslinked hydrophilic, biocompatible hydrated polymer gel prepared by reacting together water and a prepolymer in a prepolymer-to-water ratio of about 1:1 to about 1:20, said prepolymer prepared by:
- (a) selecting diols or polyols, at least 75% of which are oxyethylene-based diols or polyols having an average molecular weight of about 7000 to about 30,000, and
- (b) reacting said diols or polyols with an aliphatic or cycloaliphatic polyisocyanate at an isocyanate-to-hydroxyl ratio of about 1.8 to about 2.2 so that essentially all of the hydroxyl groups of said diols or polyols are capped with polyisocyanate and the resulting prepolymer has an isocyanate concentration of no more than 0.46 milliequivalents per gram.
A prepolymer for preparing a hydrophilic, biocompatible polymer gel characterized by transparency and by resistance to nonspecific protein adsorption, said prepolymer consisting of oxyethylene-based diols or polyols having an average molecular weight of about 7000 to about 30,000, said diols or polyols having essentially all of the hydroxyl groups capped with an aliphatic or cycloaliphatic polyisocyanate, and said prepolymer having an isocyanate concentration of no more than 0.46 meq/gm and having the ability to gel water upon polymerization in prepolymer-to-water ratios of about 1:1 to about 1:20.
Dependencies are inferred from the claim text.