Omniphobic polyurethane compositions, related articles, and related methods

Patent metadata

Field	Value
Publication number	US-11053337-B2
Application number	US-202016963896-A
Country	US
Kind code	B2
Filing date	Mar 2, 2020
Priority date	Mar 5, 2019
Publication date	Jul 6, 2021
Grant date	Jul 6, 2021

Abstract

The disclosure relates to a thermoset omniphobic composition, which includes a thermoset polymer with first, second, and third backbone segments, first urethane groups linking the first and third backbone segments, and second urethane groups linking the first and second backbone segments. The first, second, and third backbone segments generally correspond to urethane reaction products of polyisocyanate(s), hydroxy-functional hydrophobic polymer(s), and polyol(s), respectively. The thermoset omniphobic composition has favorable omniphobic properties, for example as characterized by water and/or oil contact and/or sliding angles. The thermoset omniphobic composition can be used as a coating on any of a variety of substrates to provide omniphobic properties to a surface of the substrate. Such omniphobic coatings can be scratch-resistant, ink/paint resistant, dirt-repellent, and optically clear. The thermoset omniphobic composition can be applied by different coating methods including cast, spin, roll, spray and dip coating methods.

First claim

What is claimed is:

1. A thermoset omniphobic composition comprising:
a thermoset polymer comprising a crosslinked backbone, the crosslinked backbone comprising:
(i) first backbone segments,
(ii) second backbone segments,
(iii) third backbone segments,
(iv) first urethane groups linking the first backbone segments and the third backbone segments, and
(v) second urethane groups linking the first backbone segments and the second backbone segments;

wherein:
the first backbone segments have a structure corresponding to a urethane reaction product from at least one polyisocyanate,
the second backbone segments have a structure corresponding to a urethane reaction product from at least one hydroxy-functional hydrophobic polymer having a glass transition temperature (T g ) of 70° C. or less,
the third backbone segments have a structure corresponding to a urethane reaction product from at least one polyol,
the first urethane groups have a structure corresponding to a urethane reaction product of the polyisocyanate and the polyol, and
the second urethane groups have a structure corresponding to a urethane reaction product of the polyisocyanate and the hydroxy-functional hydrophobic polymer.

2. The composition of claim 1 , wherein the polyisocyanate comprises a diisocyanate.

3. The composition of claim 1 , wherein the polyisocyanate comprises a triisocyanate.

4. The composition of claim 1 , wherein the polyisocyanate is selected from the group consisting of 1,5-naphthylene diisocyanate, 4,4′-diphenylmethane diisocyanate (MDI), hydrogenated MDI, xylene diisocyanate (XDI), tetramethylxylol diisocyanate (TMXDI), 4,4′-diphenyl-dimethylmethane diisocyanate, di- and tetraalkyl-diphenylmethane diisocyanate, 4,4′-dibenzyl diiso-cyanate, 1,3-phenylene diisocyanate, isophorone diisocyanate,1,4-phenylene diisocyanate, one or more isomers of tolylene diisocyanate (TDI), 1-methyl-2,4-diiso-cyanatocyclohexane, 1,6-diisocyanato-2,2,4-trimethyl-hexane, 1,6-diisocyanato-2,4,4-trimethylhexane, 1-iso-cyanatomethyl-3-isocyanato-1,5,5-trimethylcyclohexane, chlorinated and brominated diisocyanates, phosphorus-containing diisocyanates, 4,4′-diisocyanatophenyl-perfluoroethane, tetramethoxybutane 1,4-diisocyanate, butane 1,4-diisocyanate, hexane 1,6-diisocyanate (HDI), HDI dimer (HDID), HDI trimer (HDIT), HDI biuret, dicyclohexylmethane diisocyanate, cyclohexane 1,4-diisocyanate, ethylene diisocyanate, phthalic acid bisisocyanatoethyl ester, 1-chloromethylphenyl 2,4-diisocyanate, 1-bromomethylphenyl 2,6-diisocyanate, 3,3-bischloromethyl ether 4,4′-diphenyldiisocyanate, trimethylhexamethylene diisocyanate, 1,4-diisocyanato-butane, 1,2-diisocyanatododecane, and combinations thereof.

5. The composition of claim 1 , wherein the hydroxy-functional hydrophobic polymer is selected from the group consisting of hydroxy-functional polysiloxanes, hydroxy-functional poly(fluorosiloxanes), hydroxy-functional polyperfluoroethers, hydroxy-functional polybutadienes, hydroxy-functional polyisobutenes, hydroxy-functional branched polyolefins, hydroxy-functional poly(meth)acrylates, hydroxy-functionalized polypropylene glycol, and combinations thereof.

6. The composition of claim 1 , wherein the hydroxy-functional hydrophobic polymer comprises a monohydroxy-functional polysiloxane.

7. The composition of claim 1 , wherein the hydroxy-functional hydrophobic polymer comprises a dihydroxy-functional polysiloxane.

8. The composition of claim 1 , wherein the hydroxy-functional hydrophobic polymer comprises at least three hydroxy groups per polymeric chain.

9. The composition of claim 1 , wherein the hydroxy-functional hydrophobic polymer comprises a hydroxy-functional polyperfluoroether.

10. The composition of claim 1 , wherein the hydroxy-functional hydrophobic polymer comprises a hydroxy-functional polybutadiene.

11. The composition of claim 1 , wherein the hydroxy-functional hydrophobic polymer comprises a hydroxy-functional polyisobutene.

12. The composition of claim 1 , wherein the hydroxy-functional hydrophobic polymer comprises a hydroxy-functional branched polyolefin.

13. The composition of claim 1 , wherein the hydroxy-functional hydrophobic polymer comprises a hydroxy-functional poly(meth)acrylate.

14. The composition of claim 1 , wherein the hydroxy-functional hydrophobic polymer has a glass transition temperature in a range from −150° C. to 70° C.

15. The composition of claim 1 , wherein the hydroxy-functional hydrophobic polymer is a liquid at a temperature in a range from −20° C. to 40° C.

16. The composition of claim 1 , wherein the hydroxy-functional hydrophobic polymer has a molecular weight ranging from 300 to 200,000 g/mol.

17. The composition of claim 1 , wherein the polyol comprises a diol.

18. The composition of claim 1 , wherein the polyol comprises three or more hydroxyl groups.

19. The composition of claim 1 , wherein the polyol is selected from the group consisting of polyether polyols, hydroxlated (meth)acrylate oligomers, glycerol, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, isosorbides, neopentyl glycol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, glycerol, trimethylolpropane, 1,2,6-hexanetriol, triglycerides triols/diols from plant oil, castor oil, pentaerythritol, (meth)acrylic polyols, polyester diols, polyester polyols, polyurethane diols, polyurethane polyols, polypropylene glycols, and combinations thereof.

20. The composition of claim 1 , wherein at least one of the polyisocyanate and the polyol comprises a biobased polyisocyanate or a biobased polyol, respectively.

21. The composition of claim 1 , wherein the first backbone segments are present in an amount ranging from 10 wt. % to 90 wt. % relative to the thermoset polymer.

22. The composition of claim 1 , wherein the second backbone segments are present in an amount ranging from 0.01 wt. % to 20 wt. % relative to the thermoset polymer.

23. The composition of claim 1 , wherein the third backbone segments are present in an amount ranging from 10 wt. % to 90 wt. % relative to the thermoset polymer.

24. The composition of claim 1 , wherein the thermoset polymer crosslinked backbone further comprises:
fourth backbone segments having a structure corresponding to a urethane reaction product of at least one monoisocyanate monomer.

25. The composition of claim 24 , wherein the fourth backbone segments are present in an amount ranging from 0.01 wt. % to 4 wt. % relative to the thermoset polymer.

26. The composition of claim 1 , further comprising one or more additives selected from the group consisting of nanoclay, graphene oxide, graphene, silicon dioxide (silica), aluminum oxide, cellulose nanocrystals, carbon nanotubes, titanium dioxide (titania), diatomaceous earth, biocides, pigments, dyes, thermoplastics, UV inhibitors, electrostatic charge dissipating compounds, and combinations thereof.

27. The composition of claim 1 , wherein the composition has a water contact angle in a range from 90° to 120°.

28. The composition of claim 1 , wherein the composition has an oil contact angle in a range from 1 to 65°.

29. The composition of claim 1 , wherein the composition has a water sliding angle in a range from 1° to 30° for a 75 μl droplet.

Assignees

• Rabnawaz Muhammad
• Univ Michigan State

Inventors

• Rabnawaz Muhammad

Classifications

• C08G18/61 Primary

  Polysiloxanes · CPC title

• C09D5/1681

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

• C08G18/792

  formed by oligomerisation of aliphatic and/or cycloaliphatic isocyanates or isothiocyanates · CPC title

• C08G18/289

  containing silicon · CPC title

• C08G18/244

  tin salts of carboxylic acids · CPC title