Method of using water erodible marine antifouling coating

Patent metadata

Field	Value
Publication number	US-11518891-B2
Application number	US-202016809152-A
Country	US
Kind code	B2
Filing date	Mar 4, 2020
Priority date	Mar 4, 2020
Publication date	Dec 6, 2022
Grant date	Dec 6, 2022

Abstract

A method is described for inhibiting marine fouling on a surface. The surface is contacted with a composition comprising a waterborne polyurethane that is crosslinked with an acrylic acid functionalized polysaccharide, water, and a preservative. The composition is then dried to form a deposited film. The polysaccharide may be xanthan.

First claim

The invention claimed is:

1. A method of inhibiting marine fouling of a surface, the method comprising:
contacting the surface with a composition to produce a coated surface, the composition comprising:
a waterborne polyurethane (WBPU) crosslinked with an acrylic acid functionalized polysaccharide;
water; and
a preservative dispersed in the crosslinked WBPU, and

drying the coated surface to produce a treated surface having a deposited film.

2. The method of claim 1 , wherein the acrylic acid functionalized polysaccharide is present in the deposited film at a weight percentage of 0.1-5.0 wt % relative to a total weight of the deposited film.

3. The method of claim 1 , wherein the polysaccharide is at least one selected from the group consisting of xanthan, beta-glucan, dextran, inulin, galactan, glycogen, hemicellulose, levan, lignin, mannan, pectin, amylopectin, and amylose.

4. The method of claim 1 , wherein the acrylic acid functionalized polysaccharide comprises 1-50 wt % acrylic acid functional groups relative to a total weight of the acrylic acid functionalized polysaccharide.

5. The method of claim 1 , wherein the polysaccharide is xanthan.

6. The method of claim 1 , wherein the composition comprises 50-90 wt % water relative to a total weight of the composition.

7. The method of claim 1 , wherein the preservative is present at a weight percentage of 0.01-2.0 wt % relative to a total weight of the composition.

8. The method of claim 1 , wherein the composition further comprises a pigment.

9. The method of claim 1 , wherein the composition consists of the crosslinked WBPU, the preservative, and water.

10. The method of claim 1 , wherein the contacting is done by electrocoating, spraying, electrostatic spraying, dipping, rolling, brushing, dropping, spin coating.

11. The method of claim 1 , wherein the preservative is zinc pyrithione.

12. The method of claim 1 , wherein the deposited film has a density in a range of 0.8-2.0 g/cm 3 .

13. The method of claim 1 , wherein the crosslinked WBPU has a number average molecular weight in a range of 26-32 kDa.

14. The method of claim 13 , wherein the number average molecular weight decreases to 22-24 kDa following at least 24 h of immersion in water, seawater, or brine.

15. The method of claim 1 , wherein the deposited film has a water contact angle in a range of 45°-67°.

16. The method of claim 1 , wherein the deposited film, when immersed in water, seawater, or brine for at least 24 hours, absorbs no more than 15 wt % water in relation to a weight of the deposited film.

17. The method of claim 1 , wherein the deposited film is in the form of a layer in direct contact with the surface, the deposited film having an average thickness in a range of 1-200 μm.

18. The method of claim 1 , wherein the deposited film, when placed in contact with water, seawater, or brine for 90 days, has a dry weight loss in a range of 1.5-8.0 wt % relative to an initial dry weight.

Assignees

• Univ King Fahd Pet & Minerals

Inventors

• Rahman Mohammad Mizanur
• Zahir Md Hasan
• Mazumder Mohammad Abu Jafar

Classifications

• C08J2327/06

  Homopolymers or copolymers of vinyl chloride · CPC title

• C08K5/56

  Organo-metallic compounds, i.e. organic compounds containing a metal-to-carbon bond · CPC title

• B05D1/005

  Spin coating · CPC title

• C08B37/0033

  Xanthan, i.e. D-glucose, D-mannose and D-glucuronic acid units, saubstituted with acetate and pyruvate, with a main chain of (beta-1,4)-D-glucose units; Derivatives thereof · CPC title

• B05D1/007

  using an electrostatic field (B05D1/02 - B05D1/16 take precedence) · CPC title