Polyurethane-grafted hydrogels

Abstract

An article comprising two chemically grafted polymer layers comprising a hydrogel layer and an end-functionalized polyurethane layer. The invention also includes methods of making and using the article.

What is claimed is: 
     
         1 . A method of making a material that can be attached to bone, comprising the steps of:
 applying a solution comprising a polyurethane precursor comprising reactive endgroups, solvent, photoinitiator and crosslinker to a first polyurethane that is grafted to a hydrogel;   polymerizing the polyurethane precursor; and   treating with heat and convection to remove the solvent to yield a second polyurethane coated on a polyurethane grafted hydrogel.   
     
     
         2 . The method of  claim 1  wherein the second polyurethane comprises polycarbonate urethane or polyether urethane. 
     
     
         3 . The method of  claim 1  wherein the reactive endgroups comprise one or more of acrylamide, acrylate, allyl ether, methacrylate, and vinyl. 
     
     
         4 . The method of  claim 1  wherein the solvent comprises one or more of dimethyacetamide, dimethyl sulfoxide, and tetrahydrofuran. 
     
     
         5 . The method of  claim 1  wherein the applying step further comprises a salt. 
     
     
         6 . A method of attaching an article to a bone, the article comprising a porous polyurethane comprising a photoinitiator and a crosslinker, the method comprising the steps of:
 placing the porous polyurethane in apposition to the bone; and   polymerizing the porous polyurethane to attach the article to the bone.   
     
     
         7 . The method of  claim 6  further comprising causing the porous polyurethane to contact and flow into bone. 
     
     
         8 . The method of  claim 6  wherein the article further comprises a second polyurethane attached to the porous polyurethane. 
     
     
         9 . The method of  claim 8  wherein the article further comprises a hydrogel. 
     
     
         10 . The method of  claim 6  wherein the polymerizing step comprises exposing the porous polyurethane to UV light, heat, or a chemical initiator.