Superhydrophobic and self-cleaning substrate and a method of coating

Patent metadata

Field	Value
Publication number	US-2017225195-A1
Application number	US-201615387142-A
Country	US
Kind code	A1
Filing date	Dec 21, 2016
Priority date	Feb 9, 2016
Publication date	Aug 10, 2017
Grant date	—

Abstract

A superhydrophobic and self-cleaning surface including a substrate and a superhydrophobic layer. The superhydrophobic layer having a reacted form of octadecyltrichlorosilane. The octadecyltrichlorosilane is disposed on and crosslinked to a surface of the substrate via surface hydroxyl groups. The surface exhibits a rms roughness of 40 nm to 60 nm, a water contact angle of 155° to 180°, and a contact angle hysteresis of less than 15°. A method of preparing the substrate with a superhydrophobic and self-cleaning surface including treating a substrate with a plasma treatment, contacting the substrate with water or an alcohol to form an hydroxylated substrate, contacting the hydroxylated substrate with a solution of octadecyltrichlorosilane in an alkane solvent at a concentration in the range of 0.05 M to 0.3 M, and drying the solution on to the substrate under ambient air to form the superhydrophobic and self-cleaning surface on the substrate.

First claim

1 . A substrate with a superhydrophobic and self-cleaning surface, comprising:
a substrate; and a superhydrophobic layer comprising octadecyltrichlorosilane in reacted form; wherein the superhydrophobic layer is disposed on and crosslinked to a surface of the substrate via surface hydroxyl groups; and wherein the substrate with the superhydrophobic and self-cleaning surface has a root mean square roughness of 40 nm to 60 nm, a water contact angle of 155° to 180°, and a contact angle hysteresis of less than 15°.

2 . The substrate with a superhydrophobic and self-cleaning surface of claim 1 , wherein the substrate is a glass, a hard plastic, a non-woven fabric, a cotton fabric, a non-woven synthetic polymer fabric, or a combination thereof.

3 . The substrate with a superhydrophobic surface and self-cleaning surface of claim 1 , wherein the superhydrophobic layer has protrusions which have a height from peak to valley in the range of 0.9 nanometers to 500 nanometers.

4 . The substrate with a superhydrophobic surface and self-cleaning surface of claim 3 , wherein the protrusions have a peak width in the range of 40 nm to 110 nm.

5 . The substrate with a superhydrophobic and self-cleaning surface of claim 1 , wherein the superhydrophobic layer comprises pores having a pore size in the range of 140 nm to 260 nm and a mean pore size of 200 nm.

6 . The substrate with a superhydrophobic and self-cleaning surface of claim 1 , which is resistant to particles having a size of at least 0.8 micron.

7 . The substrate with a superhydrophobic and self-cleaning surface of claim 1 , wherein the superhydrophobic layer comprises a network of cylindrical fibers.

8 . The substrate with a superhydrophobic and self-cleaning surface of claim 1 wherein the cylindrical fibers have a diameter in the range of 45 nm to 100 nm.

9 . The substrate with a superhydrophobic and self-cleaning surface of claim 1 , wherein the reacted form of the octadecyltrichlorosilane comprises an octadecylchlorosilane, an octadecyldichlorosilane, or a polyoctadecylsilane crosslinked by a condensation reaction between at least one Si—Cl group and at least one of the surface hydroxyl groups on the substrate.

10 . A method of preparing a substrate with a superhydrophobic and self-cleaning surface comprising:
treating a substrate with a plasma treatment under a reduced pressure of 0.5 atm to vacuum; removing the substrate from the reduced pressure and contacting the substrate with water, an alcohol, or both to form a hydroxylated substrate; contacting the hydroxylated substrate with a solution comprising octadecyltrichlorosilane and an alkane solvent, wherein a concentration of the octadecyltrichlorosilane in the alkane solvent is in the range of 0.05 M to 0.3 M; and drying the solution on to the substrate under air to form the superhydrophobic and self-cleaning surface on the substrate.

11 . The method of claim 10 , wherein the plasma treatment is at least one selected from the group consisting of an oxygen plasma, an argon plasma treatment, and a nitrogen plasma treatment.

12 . The method of claim 10 , wherein the alkane is hexane.

13 . The method of claim 10 , wherein the drying is under a heated air stream.

14 . The method of claim 10 , wherein the treating is for 1 minute to 5 minutes under a vacuum.

15 . The method of claim 10 , further comprising a second contacting of the dried substrate with a superhydrophobic and self-cleaning surface with a second solution comprising an octadecyltrichlorosilane, an octadecyldichloro silane, an octadecylmonochlorosilane, a reactive polyoctadecylsilane, or a combination thereof in an alkane solvent at a concentration in the range of 0.05 M to 2 M.

16 . The method of claim 10 , wherein the substrate is a glass, a hard plastic, a non-woven fabric, a cotton fabric, a non-woven synthetic polymer fabric, or a combination thereof.

17 . The method of claim 10 , wherein the superhydrophobic and self-cleaning surface comprises a network of cylindrical fibers having a diameter in the range of 45 nm to 100 nm.

18 . The method of claim 10 , wherein the superhydrophobic and self-cleaning surface exhibits a root mean square roughness of 40 nm to 60 nm, a water contact angle of 155° to 180°, and a contact angle hysteresis of less than 15°.

Assignees

• Univ King Fahd Pet & Minerals

Inventors

• Matin Asif
• Merah Necar

Classifications

• B05D2201/00

  Polymeric substrate or laminate · CPC title

• B05D3/142

  Pretreatment · CPC title

• B05D5/08 Primary

  to obtain an anti-friction or anti-adhesive surface (rendering particulate materials free-flowing in general, e.g. making them hydrophobic B01J2/30) · CPC title

• B05D2203/35

  Glass · CPC title

• B05D2518/12

  Ceramic precursors (polysiloxanes, polysilazanes) · CPC title