Superhydrophobic poly(dimethylsiloxane) and methods for making the same
View Patent ↗A hydrophobic coating having a contact angle of at least about 150 degrees is disclosed herein, which coating comprises: a polymer substrate comprising a first linker incorporated therein at a specified surface density of from about 3×10 −4 to about 9×10 −8 units per nm 2 ; a first polymer layer in contact with said first linker; a second linker in contact with said first polymer layer; and a second polymer layer in contact with said second linker. Also disclosed herein are methods for producing the hydrophobic coating. This hydrophobic coating is useful for making microfluidic devices having a hydrophobic coating on the microfluidic channels, as well as other uses in the field of microfluidics.
1. An article comprising a hydrophobic coating having a contact angle of at least about 150 degrees, wherein the coating comprises:
a polymer substrate comprising poly(dimethyl) siloxane (PDMS) and a first linker incorporated therein at a specified surface density of from about 3×10 −4 to about 9×10 −8 units per nm 2 ;
a first polymer layer in contact with said first linker;
a second linker in contact with said first polymer layer; and
a second polymer layer in contact with said second linker; wherein the article is selected from the group consisting of a microfluidic device, wherein the microfluidic device comprises at least one channel disposed thereon, a lab-on-a-chip, a boat, and a marine monitoring device.
2. The article of claim 1 wherein the article is protein resistant.
3. The article of claim 1 wherein the article is marine antifoulable.
4. The article of claim 1 , wherein the first polymer layer is bonded to the first linker by a carbon-carbon bond.
5. The article of claim 1 , wherein the second linker is bonded to the first polymer layer by an ester bond.
6. The article of claim 1 , wherein the second polymer layer is bonded to the second linker by a carbon-carbon bond.
7. The article of claim 1 , wherein the first linker comprises an alkyl group with a terminal functional group.
8. The article of claim 1 , wherein the first linker comprises a linear (C6-C12) alkyl group with a terminal alpha-haloester group.
9. The article of claim 1 , wherein the first polymer layer comprises polyethylene glycol.
10. The article of claim 1 , wherein the second linker comprises a carbonyl group.
11. The article of claim 1 , wherein the second polymer layer comprises fluorine.
12. A microfluidic device comprising:
at least one channel disposed thereon; and
a hydrophobic coating having a contact angle of at least about 150 degrees, wherein the coating comprises:
a polymer substrate comprising poly(dimethyl) siloxane (PDMS) and a first linker incorporated therein at a specified surface density of from about 3×10 −4 to about 9×10 −8 units per nm 2 ;
a first polymer layer in contact with said first linker;
a second linker in contact with said first polymer layer; and
a second polymer layer in contact with said second linker.
13. A method for making a hydrophobic coating having a contact angle of at least about 150 degrees, said method comprising:
1) polymerizing a mixture comprising a poly(dimethyl-methylvinylsiloxane) prepolymer, poly(dimethyl-methylhydrogensiloxane) precursors and undec-10-enyl-2-bromo-2-methylpropanoate, under thermal conditions to form a polymer substrate;
2) contacting oligo(ethylene glycol) methacrylate with said polymer substrate under first polymerizing conditions to provide a first polymer layer bound to the polymer substrate through the undec-10-enyl-2-bromo-2-methylpropanoate;
3) contacting 2-bromoisobutyryl bromide with said first polymer layer under reaction conditions to provide a reactive surface; and
4) contacting 1H, 1H, 2H, 2H-perfluorodecyl methacrylate with said reactive surface under second polymerizing conditions to provide the hydrophobic coating.
14. The method of claim 13 , wherein the first polymerizing conditions comprise metal catalyzed polymerization.
15. The method of claim 13 , wherein the second polymerizing conditions comprise metal catalyzed polymerization.
16. The method of claim 13 , wherein the ratio of poly(dimethyl-methylvinylsiloxane) prepolymer,and poly(dimethyl-methylhydrogensiloxane) precursors to undec-10-enyl-2-bromo2-methylpropanoate is about 10:1:10 −3 .
17. The method of claim 13 , wherein the surface density of undec-10-enyl-2-bromo-2-methylpropanoate is about 1.0×10 −5 units per nm 2 .
18. The method of claim 13 , wherein the first polymerizing conditions comprise heating the monomer and linker to a temperature of from about 25° C. to about 90° C.
19. The method of claim 13 , wherein the reaction conditions comprise acetylation conditions.
20. The method of claim 13 , wherein the second polymerizing conditions comprise heating the monomers to about 80° C.