Aqueous dispersions

Abstract

Aqueous dispersions of cationic water-soluble polymers are provided, as well as processes for making and methods of using the same.

We claim:  
     
         1 . An aqueous dispersion comprising: 
 a first cationic polymer comprising acrylamide recurring units and recurring units of a quaternary salt of a dialkylamino(alk)acrylate, wherein said first cationic polymer is substantially free of hydrophobic recurring units;    a second cationic polymer;    a first kosmotropic salt; and    a second kosmotropic salt;    wherein said aqueous dispersion contains a total amount of about 5% or greater, by weight based on total weight, of said first kosmotropic salt and said second kosmotropic salt.    
     
     
         2 . The aqueous dispersion of  claim 1  wherein said recurring units of a quaternary salt of a dialkylamino(alk)acrylate are recurring units selected from the group consisting of methyl chloride salt of diethylaminoethylacrylate, dimethyl sulfate salt of diethylaminoethylacrylate, methyl chloride salt of dimethylaminoethylacrylate, and dimethyl sulfate salt of dimethylaminoethylacrylate.  
     
     
         3 . The aqueous dispersion of  claim 1  wherein said recurring units of a quaternary salt of a dialkylamino(alk)acrylate are recurring units of methyl chloride quaternary salt of dimethylaminoethylacrylate.  
     
     
         4 . The aqueous dispersion of  claim 3  wherein said first kosmotropic salt is selected from the group consisting of ammonium sulfate and sodium sulfate.  
     
     
         5 . The aqueous dispersion of  claim 4  wherein said second kosmotropic salt contains an anion selected from the group consisting of acetate, tartrate and citrate.  
     
     
         6 . The aqueous dispersion of  claim 4  wherein said first kosmotropic salt and said second kosmotropic salt are each individually present in an amount of about 1% or greater, by weight based on total weight.  
     
     
         7 . The aqueous dispersion of  claim 1  further comprising a viscosity-reducing additive selected from the group consisting of glycerin, glycerol, alcohol, and glycol.  
     
     
         8 . The aqueous dispersion of  claim 1  having a bulk viscosity of about 2,500 cps or less.  
     
     
         9 . The aqueous dispersion of  claim 1  having a standard viscosity of about 2.0 cps or greater.  
     
     
         10 . An aqueous dispersion comprising: 
 a first cationic polymer comprising acrylamide recurring units and recurring units selected from the group consisting of methyl chloride salt of diethylaminoethylacrylate, dimethyl sulfate salt of diethylaminoethylacrylate, methyl chloride salt of dimethylaminoethylacrylate, and dimethyl sulfate salt of dimethylaminoethylacrylate, wherein said first cationic polymer is substantially free of hydrophobic recurring units;    a second cationic polymer;    a first kosmotropic salt selected from the group consisting of ammonium sulfate and sodium sulfate; and    a second kosmotropic salt containing an anion selected from the group consisting of acetate, tartrate and citrate;    wherein said aqueous dispersion contains a total amount of about 5% or greater, by weight based on total weight, of said first kosmotropic salt and said second kosmotropic salt.    
     
     
         11 . An aqueous dispersion comprising: 
 a first cationic polymer comprising acrylamide recurring units and recurring units of a quaternary salt of a dialkylamino(alk)acrylate;    a second cationic polymer;    a first kosmotropic salt selected from the group consisting of ammonium sulfate and sodium sulfate; and    a second kosmotropic salt containing an anion selected from the group consisting of acetate, tartrate and citrate; and    a viscosity-reducing additive;    wherein said aqueous dispersion contains a total amount of about 5% or greater, by weight based on total weight, of said first kosmotropic salt and said second kosmotropic salt; and    wherein said aqueous dispersion has a weight average molecular weight of greater than 2,000,000.    
     
     
         12 . The aqueous dispersion of  claim 11  wherein said recurring units of a quaternary salt of a dialkylamino(alk)acrylate are recurring units selected from the group consisting of methyl chloride salt of diethylaminoethylacrylate, dimethyl sulfate salt of diethylaminoethylacrylate, methyl chloride salt of dimethylaminoethylacrylate, and dimethyl sulfate salt of dimethylaminoethylacrylate.  
     
     
         13 . The aqueous dispersion of  claim 12  wherein said first cationic polymer further comprises recurring units of a benzyl chloride salt of dimethylaminoethylacrylate.  
     
     
         14 . The aqueous dispersion of  claim 13  wherein said first kosmotropic salt is ammonium sulfate.  
     
     
         15 . The aqueous dispersion of  claim 14  wherein said second kosmotropic salt contains an acetate anion.  
     
     
         16 . The aqueous dispersion of  claim 15  wherein said wherein said first kosmotropic salt and said second kosmotropic salt are each individually present in an amount of about 1% or greater, by weight based on total weight.  
     
     
         17 . The aqueous dispersion of  claim 11  wherein said aqueous dispersion has a bulk viscosity of about 2,500 cps or less.  
     
     
         18 . The aqueous dispersion of  claim 11  wherein said viscosity-reducing additive is selected from the group consisting of glycerin, glycerol, alcohol, and glycol.