Filtration membrane with covalently grafted fouling-resistant polymer

Abstract

A method of photo-grafting onto a separation membrane a copolymer includes at least one of: For example, in Structure 1A, x 1 ≧2 and y 1 ≧1; R 1 and R 2 are independently selected from the group consisting of CH 3 and H; R 3 is independently selected from the group consisting of poly(oxyalkylene), quaternary ammonium salts, pyridinium salts, sulfonium salts, sulfobetaines, carboxybetaines, alcohols, phenols, tertiary amines, aryl groups; linear, branched and cyclic alkylenes; linear, branched and cyclic heteroalkylenes; linear, branched and cyclic fluoroalkylenes; and siloxyl; R 4 is independently selected from the group consisting of linear, branched, and cyclic alkylenes; linear, branched and cyclic hetroalkylenes; linear, branched and cyclic fluoroalkylenes; phenyl; and siloxyl; and Z 1 is 0 or 1.

1 . A membrane comprising:
 a support layer; and   an active layer over the support layer, wherein the active layer comprises a surface having covalently bound thereto a poly(meth)acrylate polymer comprising repeat units selected from the group consisting of:   
       
         
           
           
               
               
           
         
       
       wherein, in Structure 1A: 
       x 1 ≧2 and y 1 ≧1; 
       R 1  and R 2  are independently selected from the group consisting of CH 3  and H; 
       R 3  is independently selected from the group consisting of poly(oxyalkylene), quaternary ammonium salts, pyridinium salts, sulfonium salts, sulfobetaines, carboxybetaines, alcohols, phenols, tertiary amines, aryl groups; linear, branched and cyclic alkylenes; linear, branched and cyclic heteroalkylenes; linear, branched and cyclic fluoroalkylenes; and siloxyl; 
       R 4  is independently selected from the group consisting of linear, branched, and cyclic alkylenes; linear, branched and cyclic hetroalkylenes; linear, branched and cyclic fluoroalkylenes; phenyl; and siloxyl; and 
       z 1  is 0 or 1; 
       and; 
       
         
           
           
               
               
           
         
       
       wherein, in Structure 1B: 
       x 2 ≧2 and y 2 ≧1; 
       R 5  and R 6  are independently selected from the group consisting of CH 3  and H; 
       R 7  is independently selected from the group consisting of poly(oxyalkylene), quaternary ammonium salts, pyridinium salts, sulfonium salts, sulfobetaines, carboxybetaines, alcohols, phenols, tertiary amines, aryl groups; linear, branched and cyclic alkylenes; linear, branched and cyclic heteroalkylenes; linear, branched and cyclic fluoroalkylenes; and siloxyl; and 
       z 2  is 0 or 1. 
     
     
         2 . The membrane of  claim 1 , wherein the active layer is selected from the group consisting of polysulfones, polacrylonitrile, and PVDF. 
     
     
         3 . The membrane of  claim 1 , wherein the molecular weight of the polymer is 1000 to 50,000 g/mole. 
     
     
         4 . The membrane of  claim 1 , wherein R 4  in Structure 1A is phenyl. 
     
     
         5 . The membrane of  claim 1 , wherein R 7  in Structure 1B is a sulfonium salt. 
     
     
         6 . The membrane of  claim 1 , wherein Structure 1A is represented by the following: 
       
         
           
           
               
               
           
         
       
     
     
         7 . The membrane of  claim 1 , wherein Structure 1B is represented by the following: 
       
         
           
           
               
               
           
         
       
     
     
         8 . The membrane of  claim 1 , wherein Structure 1B is represented by the following: 
       
         
           
           
               
               
           
         
       
     
     
         9 . The membrane of  claim 1 , wherein the membrane is formed by applying to the active layer an aqueous solution comprising a polymer of Structure 1A or a polymer of Structure 1B, and exposing the solution to an actinic light source to graft the polymer to the active layer. 
     
     
         10 . A membrane comprising an active layer with a surface having covalently bound thereto a polymer comprising the following repeat units: 
       
         
           
           
               
               
           
         
       
       wherein: 
       x 1 ≧2 and y 1 ≧1; 
       R 1  and R 2  are independently selected from the group consisting of CH 3  and H; 
       R 3  is independently selected from the group consisting of poly(oxyalkylene), quaternary ammonium salts, pyridinium salts, sulfonium salts, sulfobetaines, carboxybetaines, alcohols, phenols, tertiary amines, aryl groups; linear, branched and cyclic alkylenes; linear, branched and cyclic heteroalkylenes; linear, branched and cyclic fluoroalkylenes; and siloxyl; 
       R 4  is independently selected from the group consisting of linear, branched, and cyclic alkylenes; linear, branched and cyclic hetroalkylenes; linear, branched and cyclic fluoroalkylenes; phenyl; and siloxyl; and 
       z 1  is 0 or 1. 
     
     
         11 . The membrane of  claim 10 , wherein the polymer is represented by the following: 
       
         
           
           
               
               
           
         
       
     
     
         12 . A membrane comprising an active layer with a surface having covalently bound thereto a polymer comprising the following repeat units: 
       
         
           
           
               
               
           
         
       
       wherein: 
       x 2 ≧2 and y 2 ≧1; 
       R 5  and R 6  are independently selected from the group consisting of CH 3  and H; 
       R 7  is independently selected from the group consisting of poly(oxyalkylene), quaternary ammonium salts, pyridinium salts, sulfonium salts, sulfobetaines, carboxybetaines, alcohols, phenols, tertiary amines, aryl groups; linear, branched and cyclic alkylenes; linear, branched and cyclic heteroalkylenes; linear, branched and cyclic fluoroalkylenes; and siloxyl; and 
       z 2  is 0 or 1. 
     
     
         13 . The membrane of  claim 12 , wherein the polymer is represented by the following: 
       
         
           
           
               
               
           
         
       
     
     
         14 . The membrane of  claim 12 , wherein the polymer is represented by the following: