Antimicrobial phase-separable glass/polymer composite articles and methods for making the same

Abstract

A method of making an antimicrobial composite article, including the steps: providing a matrix comprising a polymeric material; providing a plurality of second phase particles comprising an antimicrobial agent; melting the matrix to form a matrix melt; distributing the plurality of second phase particles in the matrix melt at a second phase volume fraction to form a composite melt; forming a composite article from the composite melt; and treating the composite article to form an antimicrobial composite article having an exterior surface comprising an exposed portion of the matrix and the plurality of second phase particles. The distributing step can employ an extrusion process. The forming a composite article step can employ an injection molding process. The treating step can employ abrading and plasma-treating the article to define the exterior surface.

What is claimed is: 
     
         1 . A method of making an antimicrobial composite article, comprising the steps:
 melting a matrix comprising a polymeric material to form a matrix melt;   distributing a plurality of second phase particles comprising an antimicrobial agent in the matrix melt at a second phase volume fraction to form a composite melt;   forming a composite article from the composite melt; and   treating the composite article to form an antimicrobial composite article comprising an exterior surface comprising an exposed portion of the matrix and the plurality of second phase particles.   
     
     
         2 . The method of  claim 1 , wherein the polymeric material of the matrix is characterized by substantial hydrophilicity, as measured by a contact angle between water and the polymeric material of less than 90°. 
     
     
         3 . The method of  claim 1 , wherein the treating step comprises abrading the composite article to form an antimicrobial composite article comprising an exterior surface comprising an exposed portion of the matrix and the plurality of second phase particles. 
     
     
         4 . The method of  claim 1 , wherein the polymeric material of the matrix is characterized by substantial hydrophobicity, as measured by a contact angle between water and the polymeric material of greater than 90°, and further wherein the exposed portion of the matrix is characterized by substantial hydrophilicity. 
     
     
         5 . The method of  claim 4 , wherein the treating step comprises abrading and plasma-treating the composite article to form the antimicrobial composite article having an exterior surface comprising an exposed portion of the matrix and the plurality of second phase particles. 
     
     
         6 . The method of  claim 5 , wherein the abrading is performed before the plasma-treating during the treating step. 
     
     
         7 . The method of  claim 5 , wherein the plasma-treating is performed before the abrading during the treating step. 
     
     
         8 . The method of  claim 1 , wherein the second phase particles comprise a phase-separated glass, and the antimicrobial agent comprises a copper-containing antimicrobial agent. 
     
     
         9 . The method of  claim 8 , wherein the phase-separated glass comprises SiO 2  and at least one of B 2 O 3 , P 2 O 5 , or R 2 O, and wherein the copper-containing antimicrobial agent is cuprite comprising a plurality of Cu 1+  ions. 
     
     
         10 . The method of  claim 1 , wherein the polymeric material is selected from the group consisting of a polypropylene, a polyolefin, and a polysulfone. 
     
     
         11 . The method of  claim 1 , wherein the melting and distributing steps comprise an extrusion process, and the forming a composite article step comprises an injection molding process. 
     
     
         12 . The method of  claim 1 , wherein the exterior surface of the antimicrobial composite article exhibits at least a log 2 reduction in a concentration of at least one of  Staphylococcus aureus, Enterobacter aerogenes , and  Pseudomonas aeruginosa  bacteria under a Modified EPA Copper Test Protocol. 
     
     
         13 . The method of  claim 1 , wherein the exterior surface of the antimicrobial composite article exhibits at least a log 3 reduction in a concentration of at least one of  Staphylococcus aureus, Enterobacter aerogenes , and  Pseudomonas aeruginosa  bacteria under a Modified EPA Copper Test Protocol. 
     
     
         14 . A method of making an antimicrobial composite article, comprising the steps:
 melting a matrix comprising a polymeric material to form a matrix melt;   distributing a plurality of second phase particles comprising a phase-separated glass comprising a copper-containing antimicrobial agent in the matrix melt at a second phase volume fraction to form a composite melt;   forming a composite article from the composite melt; and   treating the composite article to form an antimicrobial composite article comprising an exterior surface comprising an exposed portion of the matrix and the plurality of second phase particles.   
     
     
         15 . The method of  claim 14 , wherein the treating step comprises abrading the composite article to form the antimicrobial composite article having an exterior surface comprising an exposed portion of the matrix and the plurality of second phase particles. 
     
     
         16 . The method of  claim 14 , wherein the treating step comprises plasma-treating the composite article to form the antimicrobial composite article having an exterior surface comprising an exposed portion of the matrix and the plurality of second phase particles. 
     
     
         17 . The method of  claim 14 , wherein the treating step comprises abrading and plasma-treating the composite article to form the antimicrobial composite article having an exterior surface comprising an exposed portion of the matrix and the plurality of second phase particles. 
     
     
         18 . The method of  claim 14 , wherein the phase-separated glass comprises SiO 2  and at least one of B 2 O 3 , P 2 O 5 , or R 2 O, and wherein the copper-containing antimicrobial agent is cuprite comprising a plurality of Cu 1+  ions. 
     
     
         19 . The method of  claim 14 , wherein the polymeric material is selected from the group consisting of a polypropylene, a polyolefin, and a polysulfone. 
     
     
         20 . A method of making an antimicrobial composite article, comprising the steps:
 melting a matrix comprising a hydrophobic polymeric material to form a matrix melt;   extruding a plurality of second phase particles comprising a copper-containing antimicrobial agent in the matrix melt at a second phase volume fraction to form a composite melt;   injection molding a composite article from the composite melt; and   treating the composite article to form an antimicrobial composite article comprising an exterior surface comprising an exposed portion of the matrix and the plurality of second phase particles,   wherein the exposed portion of the plurality of second phase particles is distributed within the exposed portion of the matrix at a second phase area fraction within 25% of the second phase volume fraction.