Durable Superhydrophobic Surfaces

• US 20170158831A1
• Filed: 07/24/2015
• Published: 06/08/2017
• Est. Priority Date: 07/25/2014
• Status: Active Grant

• Current Assignee: University of Florida Research Foundation, Incorporated (State University System of Florida)
• Original Assignee: University of Florida Research Foundation, Incorporated (State University System of Florida)
• Inventors: SIGMUND, Wolfgang M., HSU, Shu-Hau, VASUDEVAN, Ravi Kumar
• Granted Patent: US 10,508,182 B2
• Time in Patent Office: Days
• CPC Class Codes: C08J 2383/04 Polysiloxanes
• CPC Class Codes: C08J 5/18 Manufacture of films or sheets
• CPC Class Codes: C08J 7/065 Low-molecular-weight organic substances, e.g. absorption of additives in the surface of the article
• CPC Class Codes: C08J 7/12 Chemical modification

Abstract

A superhydrophobic appliance is an elastomeric material with a surface having a multiplicity of re-entrant features. The elastomeric material can be a polydimethylsiloxane network. The superhydrophobic appliance can be formed by infusing a portion of a polydimethylsiloxane polymeric precursor partially into the pores of a porous membrane, curing to the polymeric network, and separating the membrane from the appliance to expose the superhydrophobic surface. The superhydrophobic surface can be subsequently modified to form a fluorinated surface that is oleophobic or superoleophobic in addition to being superhydrophobic.

Claims

1. A superhydrophobic appliance, comprising a polymeric network having elastomeric properties and at least one surface with a multiplicity of re-entrant features that render the surface a superhydrophobic surface.

2. The superhydrophobic appliance according to claim 1, wherein the re-entrant features have at least one dimension of 100 μ

m or less.

3. The superhydrophobic appliance according to claim 1, wherein the re-entrant features comprise non-perpendicular cylinders extending from a base of the surface.

4. The superhydrophobic appliance according to claim 1, wherein the polymeric network is a polydimethylsiloxane network.

5. The superhydrophobic appliance according to claim 1, further comprising a fluorocarbon comprising monolayer on the at least one surface, wherein the superhydrophobic surface is superhydrophobic and oleophobic or superoleophobic.

6. A method of preparing a superhydrophobic appliance according to claim 1, comprising:

providing a membrane comprising a multiplicity of pores;

providing a polymeric precursor;

contacting the polymeric precursor and a face of the membrane that accesses the pores;

forcing the polymeric precursor into the pores;

curing the polymeric precursor into a polymeric network; and

separating the membrane from the polymeric network to expose a superhydrophobic surface of a superhydrophobic appliance.

7. The method according to claim 6, wherein the polymer precursor comprises a polydimethylsiloxane resin.

8. The method according to claim 7, wherein the polydimethylsiloxane resin is an addition curable resin.

9. The method according to claim 8, wherein the addition curable resin is a hydrosilation curable resin.

10. The method according to claim 6, wherein curing is a thermal curing or a photochemical curing.

11. The method according to claim 6, wherein separating is peeling the membrane from the polymeric network.

12. The method according to claim 6, wherein separating comprises dissolving of the membrane in a solvent and removing the solvent residual on and/or absorbed within the superhydrophobic appliance.

13. The method according to claim 6, further comprising modifying the superhydrophobic surface to have a perfluorinated hydrocarbon coating on the polymeric network, wherein the superhydrophobic surface is a superhydrophobic and oleophobic or superoleophobic surface.

14. The method according to claim 13, wherein the polymeric network is a polydimethylsiloxane network and modifying comprises oxidizing the superhydrophobic surface to an oxidized surface and reacting the oxidized surface with a perfluorinated hydrocarbon silane coupling agent.

15. The method according to claim 14, wherein oxidizing comprises treating with a mixture of H₂O, HCl, and H₂O₂ and wherein the perfluorinated hydrocarbon silane coupling agent is heptadecafluoro-1,1,2,2-tetrahydrodecyltrichlorosilane.