Hydrogel composition and methods for making the same

Abstract

The invention provides a hydrogel composition comprising water and a hydrophilic polymer, wherein the hydrogel composition has (a) an ultimate tensile strength of about 10 kPa or more, (b) a compressive strength of about 70 kPa or more, or (c) an ultimate tensile strength of about 10 kPa or more and a compressive strength of about 70 kPa or more. The invention further provides methods for producing a hydrogel composition.

1 . A hydrogel composition comprising water and a hydrophilic polymer, wherein the hydrogel composition has (a) an ultimate tensile strength of about 10 kPa or more, (b) a compressive strength of about 70 kPa or more, or (c) an ultimate tensile strength of about 10 kPa or more and a compressive strength of about 70 kPa or more.  
   
   
       2 . The hydrogel composition of claims  1 , wherein the hydrophilic polymer is a melt-processable, hydrophilic polymer.  
   
   
       3 . The hydrogel composition of  claim 2 , wherein the hydrophilic polymer is a melt-processable, radiation crosslinkable, hydrophilic polymer  
   
   
       4 . The hydrogel composition of  claim 3 , wherein the hydrophilic polymer is poly(ethylene oxide).  
   
   
       5 . The hydrogel composition of  claim 1 , wherein the hydrogel composition has an ultimate tensile strength of about 35 kPa or more.  
   
   
       6 . The hydrogel composition of  claim 1 , wherein the hydrogel composition has a compressive strength of about 300 kPa or more.  
   
   
       7 . The hydrogel composition of  claim 1 , wherein the hydrogel composition further comprises a second polymer selected from the group consisting of polyethylene glycol, polyethylene glycol copolymers, poly(propylene glycol), poly(2-hydroxyethyl methacrylate), poly(vinyl alcohol), poly(acrylic acid), poly(methacrylic acid), polyvinylpyrrolidone, cellulose ether, alginate, chitosan, hyaluronate, collagen, polylactic acid, polyglycolic acid, polydioxanone, polycaprolactone, beta-hydroxy acid polymers, and mixtures thereof.  
   
   
       8 . A drug delivery device comprising the hydrogel composition of  claim 1  and an active ingredient dispersed or dissolved in the hydrogel composition.  
   
   
       9 . A wound dressing comprising the hydrogel composition of  claim 1 .  
   
   
       10 . A method for producing a hydrogel composition, the method comprising the steps of: 
 (a) providing a compression mold having an internal volume,    (b) providing a hydrogel precursor comprising a melt-processable, radiation crosslinkable, hydrophilic polymer,    (c) filling at least a portion of the internal volume of the compression mold with the precursor,    (d) compressing the precursor contained within the compression mold to form a molded body therefrom,    (e) irradiating at least a portion of the molded body to crosslink at least a portion of the hydrophilic polymer contained within the molded body, and    (f) hydrating the irradiated molded body to form a hydrogel therefrom.    
   
   
       11 . The method of  claim 10 , wherein the melt-processable, radiation crosslinkable, hydrophilic polymer has an average molecular weight of about 1,000,000 atomic mass units or more.  
   
   
       12 . The method of  claim 11 , wherein the melt-processable, radiation crosslinkable, hydrophilic polymer is poly(ethylene oxide).  
   
   
       13 . The method of  claim 10 , wherein the precursor is compressed at a pressure of about 3,800 kPa to about 14,000 kPa during step (d).  
   
   
       14 . The method of  claim 10 , wherein the precursor is heated to a temperature of about 120° C. to about 140° C. during step (d).  
   
   
       15 . The method of  claim 10 , wherein the precursor is compressed for about 5 to about 10 minutes during step (d).  
   
   
       16 . The method of  claim 10 , wherein the molded body is irradiated in step (e) by exposing the molded body to about 1.5 to about 6 Mrad of gamma radiation.  
   
   
       17 . The method of  claim 10 , wherein the molded body is hydrated by submerging at least a portion of the molded body in an aqueous solution having a temperature of about 50° C. to about 90° C. for about 120 hours to about 220 hours.  
   
   
       18 . The method of  claim 17 , wherein the aqueous solution further comprises an active ingredient selected from the group consisting of a drug, a therapeutic agent, a humectant, and mixtures thereof.  
   
   
       19 . The method of  claim 10 , wherein the hydrogel precursor further comprises an active ingredient selected from the group consisting of a drug, a therapeutic agent, a humectant, and mixtures thereof.  
   
   
       20 . A method for producing a hydrogel composition, the method comprising the steps of: 
 (a) providing a dispersion comprising a crosslinking agent,    (b) providing a hydrogel precursor comprising a melt-processable, hydrophilic polymer,    (c) coating at least a portion of the hydrogel precursor with the dispersion,    (d) providing a compression mold having an internal volume,    (e) filling at least a portion of the internal volume of the compression mold with the coated precursor produced in step (c),    (f) compressing the precursor contained within the compression mold to form a molded body therefrom and crosslink at least a portion of the hydrophilic polymer contained within the molded body, and    (g) hydrating the molded body to form a hydrogel therefrom.    
   
   
       21 . The method of  claim 20 , wherein the crosslinking agent is a peroxide.  
   
   
       22 . The method of  claim 21 , wherein the crosslinking agent is benzoyl peroxide.  
   
   
       23 . The method of  claim 20 , wherein the melt-processable, hydrophilic polymer has an average molecular weight of about 1,000,000 atomic mass units or more.  
   
   
       24 . The method of  claim 23 , wherein the melt-processable, hydrophilic polymer is poly(ethylene oxide).  
   
   
       25 . The method of  claim 20 , wherein the precursor is compressed at a pressure of about 3,800 kPa to about 14,000 kPa during step (f).  
   
   
       26 . The method of  claim 20 , wherein the precursor is heated to a temperature of about 120° C. to about 140° C. during step (f).  
   
   
       27 . The method of  claim 20 , wherein the precursor is compressed for about 5 to about 10 minutes during step (f).  
   
   
       28 . The method of  claim 20 , wherein the molded body is hydrated by submerging at least a portion of the molded body in an aqueous solution having a temperature of about 50° C. to about 90° C. for about 120 hours to about 220 hours.  
   
   
       29 . The method of  claim 28 , wherein the aqueous solution further comprises an active ingredient selected from the group consisting of a drug, a therapeutic agent, a humectant, and mixtures thereof.  
   
   
       30 . The method of  claim 20 , wherein the hydrogel precursor further comprises an active ingredient selected from the group consisting of a drug, a therapeutic agent, a humectant, and mixtures thereof.