Wet laid disposable absorbent structures with high wet strength and method of making the same

Abstract

A method of making an absorbent structure including mixing ultra-high molecular weight (“UHMW”) glyoxalated polyvinylamide adducts (“GPVM”) and/or high molecular weight (“HMW”), glyoxalated polyacrylamide and/or high cationic charge glyoxalated polyacrylamide (“GPAM”) copolymers and high molecular weight (“HMW”) anionic polyacrylamide (“APAM”) with the furnish during stock preparation of a wet laid papermaking process.

1 . A method of making an absorbent structure comprising:
 forming a stock mixture comprising cellulose fibers, high molecular weight anionic polyacrylamide, and ultra-high molecular weight glyoxalated polyvinylamide adducts, the stock mixture being devoid of polyaminoamide-epihalohydrin; and   at least partially drying the stock mixture using a wet laid process to form the absorbent structure.   
     
     
         2 . The method of  claim 1 , wherein the absorbent structure has a dichloropropanol concentration of less than 50 ppb and a chloropropanediol concentration of less than 300 ppb. 
     
     
         3 . The method of  claim 1 , wherein the stock mixture further comprises:
 an additive selected from the group consisting of chitosan, lignin, laccase polymerized lignin, hemicellulose, polymerized hemicellulose, hemp hurd, pectin, hydroxyethyl cellulose, carboxymethyl cellulose, guar gum, soy protein, chitin, polyvinylamine, polyethylenimine, and combinations thereof.   
     
     
         4 . The method of  claim 1 , further comprising laminating together two plies of the absorbent structure to form a two-ply absorbent product. 
     
     
         5 . The method of  claim 4 , wherein the absorbent product is through air dried facial tissue, napkin, or towel. 
     
     
         6 . The method of  claim 4 , wherein the absorbent product is a retail roll towel product. 
     
     
         7 . The method of  claim 4 , wherein the absorbent product has a caliper of 700 microns/2-ply to 1,300 microns/2-ply. 
     
     
         8 . The method of  claim 4 , wherein the absorbent product has a cross direction wet strength of 80 to 200 N/m.