Method of Modifying Polymer Barrier Films

Abstract

The present disclosure describes a method to modify dried polymer films using printed crosslinking agents, including that the crosslinked polymer resulting from the method exhibits greater insolubility compared to crosslinked polymers made where the crosslinking agent and the polymer are combined and applied as a homogenous solution. Articles of manufacture generated by such a method are also disclosed.

What is claimed: 
     
         1 . An article of manufacture containing a substrate comprising a crosslinked-polymer coated layer formed from a polymer, wherein crosslinking in the crosslinked-polymer layer is substantially limited to an upper surface of said crosslinked-polymer layer and substantially no crosslinking is contained within said crosslinked-polymer layer. 
     
     
         2 . The article of manufacture of  claim 1 , wherein the polymer comprises a polyvinyl alcohol, a polyethylene oxide, dextran, a starch, a hemicellulose, a cellulose ether, a lignin, polyvinylpyrrolidone, polyacrylamide, polyacrylic acid, a polyacrylates, pectin, an alginate, a protein, gelatin, corn zein, whey protein, or a combination thereof. 
     
     
         3 . The article of manufacture of  claim 1 , wherein the polymer comprises a polyvinyl alcohol. 
     
     
         4 . The article of manufacture of  claim 1 , wherein the cellulose ether comprises hydroxyethyl cellulose, hydroxypropyl cellulose, or a combination thereof. 
     
     
         5 . The article of manufacture of  claim 1 , wherein the polymer is crosslinked with a crosslinking agent comprising an aldehyde, an aldehyde-containing resin, a polyfunctional carboxylic acid, a difunctional methacrylate, ammonium zirconium carbonate, an N-lactam carboxylate, a dithiol, dimethyl urea, a di-isocyanate, a borate, a salt of a multivalent anion, an inorganic polyion, a Group 1B salt, polyamide-epichlorohydrin resin, or a combination thereof. 
     
     
         6 . The article of manufacture of  claim 1 , wherein the polymer is crosslinked with a crosslinking agent comprising an aldehyde, an aldehyde-containing resin, a dicarboxylic acid, or a combination thereof. 
     
     
         7 . The article of manufacture of  claim 1 , wherein the polymer is crosslinked with a crosslinking agent comprising an aldehyde. 
     
     
         8 . The article of manufacture of  claim 1 , wherein the polymer is crosslinked with a crosslinking agent comprising a dialdehyde. 
     
     
         9 . The article of manufacture of  claim 1 , wherein the polymer is crosslinked with a crosslinking agent comprising glyoxal, glutaraldehyde, or a mixture thereof. 
     
     
         10 . The article of manufacture of  claim 1 , wherein the polymer is crosslinked with a crosslinking agent comprising glyoxal. 
     
     
         11 . The article of manufacture of  claim 1 , wherein said substrate is a cellulosic material. 
     
     
         12 . The article of manufacture of  claim 11 , wherein said cellulosic material is selected from the group consisting of paper, paperboard, paper pulp, a carton for food storage, a bag for food storage, a shipping bag, a container for coffee or tea, a tea bag, bacon board, diapers, weed-block/barrier fabric or film, mulching film, plant pots, packing beads, bubble wrap, oil absorbent material, laminates, envelops, gift cards, credit cards, gloves, raincoats, OGR paper, a shopping bag, a compost bag, release paper, eating utensil, container for holding hot or cold beverages, cup, paper towels, plate, a bottle for carbonated liquid storage, insulating material, a bottle for non-carbonated liquid storage, film for wrapping food, a garbage disposal container, a food handling implement, a lid for a cup, paper straws, a fabric fibre, a water storage and conveying implement, paperboard from medical use, release paper, a storage and conveying implement for alcoholic or non-alcoholic drinks, an outer casing or screen for electronic goods, an internal or external piece of furniture, a curtain, upholstery, film, box, sheet, tray, pipe, water conduit, packaging for pharmaceutical products, clothing, medical device, contraceptive, camping equipment, cellulosic material that is molded and combinations thereof. 
     
     
         13 . The article of manufacture of  claim 1 , wherein said crosslinked-polymer layer affords said article of manufacture higher flexibility, lower stiffness, and/or greater elongation compared to an article of manufacture comprising a substantially similar crosslinking agent and polymer but substantial crosslinking is contained within said layer. 
     
     
         14 . The article of manufacture of  claim 1 , wherein the resulting substrate is hydrophobic. 
     
     
         15 . The article of manufacture of  claim 1 , where in the resulting substrate is lipophobic. 
     
     
         16 . The article of manufacture of  claim 1 , where in the resulting substrate exhibits a 3M grease KIT test value of between 3 and 12. 
     
     
         17 . The article of manufacture of  claim 1 , wherein said crosslinked-polymer layer is made by the steps of:
 a. applying a polymer solution comprising the polymer to said substrate;   b. drying said polymer solution on said substrate;   c. printing a crosslinking agent on said dried substrate; and   d. heating the printed substrate for a sufficient time to achieve crosslinking to form the crosslinked-polymer layer;   wherein the resulting crosslinked polymer exhibits greater insolubility relative to a crosslinked polymer generated by application of the same polymer and crosslinking agent combined in solution.