Method for applying gas-impermeable coatings

Patent metadata

Field	Value
Publication number	US-11859096-B2
Application number	US-202217984240-A
Country	US
Kind code	B2
Filing date	Nov 10, 2022
Priority date	Oct 19, 2016
Publication date	Jan 2, 2024
Grant date	Jan 2, 2024

Abstract

A method of applying a gas-impermeable coating includes forming a polyelectrolyte complex suspension. The polyelectrolyte complex suspension is applied to a substrate. The substrate having the polyelectrolyte complex applied thereon is treated. The treating reduces salt content of the polyelectrolyte complex. The treating results in a gas-impermeable coating being formed on the substrate.

First claim

What is claimed is:

1. A method of applying a gas-impermeable coating, the method comprising:
forming a polyelectrolyte complex suspension;
applying the polyelectrolyte complex suspension to a substrate, the polyelectrolyte complex suspension comprising a molar ratio of 1:3 of polycation to polyanion;
treating the substrate having the polyelectrolyte complex applied thereon, wherein the treating reduces salt content of the polyelectrolyte complex and causes solid film formation on the substrate; and
wherein, the treating results in a gas-impermeable coating being formed on the substrate.

2. The method of claim 1 , wherein the polyelectrolyte complex comprises at least two oppositely charged polyelectrolytes.

3. The method of claim 2 , wherein the polyelectrolyte complex comprises a cationic polyethylenimine (PEI) and anionic polyacrylic acid (PAA).

4. The method of claim 1 , further comprising controlling pH of the polyelectrolyte complex such that polyelectrolytes dissolve or there is a reduction of at least one of hydrogen bonding or electrostatic interaction between the polyelectrolytes.

5. The method of claim 1 , wherein the polyelectrolyte complex comprises at least one of a polycation, a polyanion, polyethylenimine, Poly(allyl amine), poly(diallyldimethyl ammonium chloride), chitosan, functionalized starch, poly(vinyl amine), poly(vinylbenzyltrimethyl-ammonium) bromide, poly(4-vinyl-N-butyl-pyridinium) chloride, poly(acrylic acid), sodium polyacrylate, poly(styrene sulfonic acid), sodium poly(styrene sulfonate), carboxymethylcellulose, alginic acid, hyaluronic acid, heparin, polyphosphoric acid, or polyphosphate salts.

6. The method of claim 1 , further comprising controlling ionic strength to thereby make the polycation and the polyanion suitable for a Meyer rod coating process.

7. The method of claim 6 , wherein the ionic strength is manipulated by addition of a salt.

8. The method of claim 1 , wherein the applying comprises dip coating.

9. The method of claim 1 , wherein the applying comprises utilizing a Meyer rod to apply the polyelectrolyte complex suspension to the substrate.

10. The method of claim 1 , wherein the treating comprises a humidity treatment.

11. The method of claim 10 , wherein the humidity treatment removes porosity and uncovers fissures.

12. The method of claim 10 , wherein the humidity treatment is conducted at greater than 95% relative humidity.

13. The method of claim 1 , wherein the treating comprises addition of a cross-linking agent.

14. The method of claim 13 , wherein method further comprises crosslinking chemical bonds of polyethylenimine and polyacrylic acid to create amide bonds.

15. The method of claim 14 , wherein the crosslinking comprises thermal crosslinking performed by high heat at 150° C. for 2 hours.

16. The method of claim 1 , wherein the treating comprises utilizing a buffer to improve durability to rinsing of the solid film formation and produce higher cohesive energy density.

17. The method of claim 16 , wherein the buffer comprises a citric acid or a citrate buffer aqueous solution.

18. The method of claim 1 , wherein the solid film formation is less than 10 microns.

19. The method of claim 1 , wherein the solid film formation has an oxygen transmission rate of less than 10 cm 3 /(m 2 ·day·atm).

Assignees

• Texas A & M Univ Sys

Inventors

• Grunlan Jaime C
• Haile Merid
• Smith Ryan

Classifications

• C09D133/02 Primary

  Homopolymers or copolymers of acids; Metal or ammonium salts thereof · CPC title

• B05D1/00

  Processes for applying liquids or other fluent materials (B05D5/00, B05D7/00 take precedence) · CPC title

• B05D1/18

  performed by dipping · CPC title

• B05D1/40

  Distributing applied liquids or other fluent materials by members moving relatively to surface · CPC title

• C08J7/048

  Forming gas barrier coatings · CPC title