Superhydrophobic powder coatings

Patent metadata

Field	Value
Publication number	US-10150875-B2
Application number	US-201213631212-A
Country	US
Kind code	B2
Filing date	Sep 28, 2012
Priority date	Sep 28, 2012
Publication date	Dec 11, 2018
Grant date	Dec 11, 2018

Abstract

A superhydrophobic coating, comprises a superhydrophobic powder with superhydrophobic particles having a three dimensional nanostructured surface topology defining pores, and a resin. The superhydrophobic particles are embedded within the resin and the resin does not fill the pores of the superhydrophobic particles such that the three dimensional surface topology of the superhydrophobic particles is preserved. A precursor powder for a superhydrophobic coating and a method for applying a superhydrophobic coating to a surface are also disclosed.

First claim

I claim:

1. A superhydrophobic coating, comprising:
a thermal set resin powder; and
a plurality of amphoteric superhydrophobic particles,
wherein each superhydrophobic particle comprises a porous silicate core having an outer surface, comprising a three dimensional, nanostructured surface topology, defining a plurality of pores, wherein each porous silicate core is hydrophilic, the superhydrophobic particles comprising a plurality of superhydrophobic regions on the surface of the silicate core comprising hydrophobic silanes bonded to the surface, and a plurality of hydrophilic regions on the surface comprising exposed portions of the silicate surface,
wherein at least a portion of the superhydrophobic particles are embedded within the thermal set resin so as to be surrounded by the resin, wherein the particles are covalently bonded to the thermal set resin via the hydrophilic silicate surface of the hydrophilic regions, and the resin does not bind to the hydrophobic silanes of the hydrophobic regions, and wherein the superhydrophobic particles are mechanically bonded to the thermal set resin by partial penetration of the pores by the resin;
wherein the pore volume of each porous core is less than 50% filled by the resin;
wherein the resin does not fill the pores of the embedded superhydrophobic particles such that the three dimensional surface topology of the superhydrophobic particles is preserved upon removal of adjacent portions of the resin.

2. The superhydrophobic coating of claim 1 , wherein the resin is hydrophobic.

3. The superhydrophobic coating of claim 1 , wherein the superhydrophobic particle comprises a hydrophobic coating, the hydrophobic coating conforming to the surface of the superhydrophobic particle so as to preserve the nanostructured surface topology.

4. The superhydrophobic coating of claim 3 , wherein the superhydrophobic particle comprises a diatomaceous earth particle.

5. The superhydrophobic coating of claim 1 , wherein the silicate is etched to provide the nanostructured surface topology.

6. The superhydrophobic coating of claim 1 , wherein the diameter of the superhydrophobic particle is between 1-20 μm.

7. The superhydrophobic coating of claim 1 , wherein the diameter of the superhydrophobic particles is between 10-20 μm.

8. The superhydrophobic coating of claim 1 , wherein the ratio of superhydrophobic particles to resin is between 1:1 and 1:10, by volume.

9. The superhydrophobic coating of claim 1 , wherein the ratio of superhydrophobic particles to resin is between 1:1.5 and 1:5, by volume.

10. The superhydrophobic coating of claim 1 , wherein the ratio of superhydrophobic particles to resin is about 1:4, by volume.

11. A superhydrophobic coating, comprising:
a thermal set dry resin powder comprising resin particles;
a plurality of amphoteric superhydrophobic particles, wherein each superhydrophobic particle comprises a porous silicate core having an outer surface, comprising a three dimensional, nanostructured surface topology, defining a plurality of pores having pore openings wherein each porous silicate core is hydrophilic, the superhydrophobic particles comprising a plurality of superhydrophobic regions on the surface of the silicate core comprising hydrophobic silanes bonded to the surface, and a plurality of hydrophilic regions on the surface comprising exposed portions of the silicate surface,
the diameter of the resin particles being larger than the pore openings of the superhydrophobic particles;
wherein after curing at least a portion of the superhydrophobic particles are embedded within the cured thermal set resin powder so as to be surrounded by and mechanically bonded to the resin by partial penetration of the pores by the resin;
wherein the pore volume of each porous core is less than 50% filled by the resin;
wherein the particles are covalently bonded to the thermal set resin via the hydrophilic silicate surface of the hydrophilic regions, and the resin does not bind to the hydrophobic silanes of the hydrophobic regions;
wherein the cured resin does not fill the pores of the embedded superhydrophobic particles such that the three dimensional surface topology of the superhydrophobic particles is preserved upon removal of adjacent portions of the resin.

12. The superhydrophobic coating of claim 11 , wherein the thermal set resin is hydrophobic.

13. The superhydrophobic coating of claim 11 , wherein the superhydrophobic particle comprises a diatomaceous earth particle.

14. The superhydrophobic coating of claim 11 , wherein the silicate is etched to provide the nanostructured surface topology.

15. The superhydrophobic coating of claim 11 , wherein the diameter of the superhydrophobic particle is between 1-20 μm.

16. The superhydrophobic coating of claim 11 , wherein the diameter of the superhydrophobic particles is between 10-20 μm.

17. The superhydrophobic coating of claim 11 , wherein the ratio of superhydrophobic particles to resin is between 1:1 and 1:10, by volume.

18. The superhydrophobic coating of claim 11 , wherein the ratio of superhydrophobic particles to resin is between 1:1.5 and 1:5, by volume.

19. The superhydrophobic coating of claim 11 , wherein the ratio of superhydrophobic particles to resin is about 1:4, by volume.

20. The superhydrophobic coating of claim 11 , wherein the resin particles are no more than 20 times the diameter of the of the superhydrophobic particles.

Assignees

• Ut Battelle Llc

Inventors

• Simpson John T

Classifications

• C09D5/1681 Primary

  Antifouling coatings characterised by surface structure, e.g. for roughness effect giving superhydrophobic coatings or Lotus effect · CPC title

• C08K7/24

  inorganic · CPC title

• C09D5/031 Primary

  characterised by particle size or shape · CPC title

• C09D7/62

  modified by treatment with other compounds · CPC title

• C08K7/26

  Silicon- containing compounds · CPC title