Hydrophobic coating composition and method of imparting hydrophobicity onto a surface
View Patent ↗The present invention relates to a method of producing a water repelling surface or imparting hydrophobicity onto a surface comprises applying a polymer-based coating composition. The water repelling surface or the hydrophobic surface imparted by the present method has at least 90° of water contact angle. The water repelling surface or the hydrophobic surface imparted by the present method is preferably on a concrete surface. The present method imparts hydrophobicity onto surfaces that are durable without an additional primer layer between the surfaces and the coating composition.
1. A method of producing a water repelling surface having a water contact angle of at least 90° on a concrete surface without a primer layer, the method comprising
providing one or more types of trialkoxysilane having at least one hydrophobic functional group with an alkene terminated group, one or more types of alkene-terminated polyfluorinated monomer that forms an oxysilane-polyfluorinated copolymer with said trialkoxysilane and an initiator for polymerization of said trialkoxysilane and said monomer,
treating said trialkoxysilane, monomer and initiator at 80-85° C. under nitrogen to form the copolymer,
formulating a polymer-based coating composition from said copolymer,
dispersing one or more types of inorganic fillers in a solvent under ultrasonic mixing to form a filler dispersion,
adding said filler dispersion to the polymer-based coating composition, and further treating the filler dispersion containing- polymer based composition at 80-85° C.,
cooling said polymer-based coating composition to room temperature, and
applying said polymer-based coating composition to said concrete surface.
2. The method of claim 1 , further comprising adding a solvent to said copolymer to formulate the polymer-based coating composition.
3. A method of producing a water repelling surface having a water contact angle of at least 90° on a concrete surface without a primer layer, the method comprising
providing one or more types of trialkoxysilane having at least one hydrophobic functional group with an alkene terminated group, one or more types of alkene-terminated polyfluorinated monomer that forms an oxysilane-polyfluorinated copolymer with said trialkoxysilane and an initiator for polymerization of said trialkoxysilane and said monomer,
treating said trialkoxysilane, monomer and initiator at 80-85° C. under nitrogen to form the copolymer,
formulating a polymer-based coating composition from said copolymer,
adding one or more silane-containing compounds having concrete penetration capability of more than 5 mm of concrete to the polymer-based coating composition,
cooling said polymer-based coating composition to room temperature, and
applying said polymer-based coating composition to said concrete surface.
4. The method of claim 3 , wherein said one or more silane-containing compounds having concrete penetration capability of more than 5 mm of concrete comprise alkyltrialkoxysilane having C3-C8 alkyl groups and C3 or C4 alkoxyl groups.
5. The method of claim 1 , wherein the trialkoxysilane and monomer are in a weight ratio from 1:2 to 2:1.
6. The method of claim 1 , wherein the initiator is less than 1 wt % of the polymer-based coating composition.
7. The method of claim 1 , wherein the inorganic filler is 0.1-20 wt % of the polymer-based coating composition.
8. The method of claim 1 , wherein the trialkoxysilane is trimethoxysilyl propyl methacrylate[] or 3-(triethoxysilyl)propyl methacrylate; the monomer is 2,2,3,3,4,4,5,5,6,6,7,7-dodecafluoroheptyl methacrylate or 2-(perfluorohexyl)ethyl methacrylate; and the initiator is benzoyl peroxide.
9. The method of claim 1 , wherein the solvent comprises ethanol, tetrahydrofuran or dimethylformamide, and the inorganic fillers comprise titanium dioxide, silicon dioxide, mica, silica fumes, talc, kaolin or a combination thereof.
10. A method of producing a water repelling surface having a water contact angle of at least 90° on a concrete surface without a primer layer, the method comprising
providing one or more types of trialkoxysilane having at least one hydrophobic functional group with an alkene terminated group, one or more types of alkene-terminated polyfluorinated monomer that forms an oxysilane-polyfluorinated copolymer with said trialkoxysilane and an initiator for polymerization of said trialkoxysilane and said monomer,
treating said trialkoxysilane, monomer and initiator at 80-85° C. under nitrogen to form the copolymer,
adding a solvent to said copolymer, wherein the solvent comprises ethanol, tetrahydrofuran or dimethylformamide,
formulating a polymer-based coating composition from said copolymer,
cooling said polymer-based coating composition to room temperature, and
applying said polymer-based coating composition to said concrete surface.
11. The method of claim 1 , wherein the water repelling surface produced has a water contact angle of greater than 100°.
12. The method of claim 3 , further comprising dispersing one or more types of inorganic fillers in a solvent under ultrasonic mixing to form a filler dispersion, adding said filler dispersion to the polymer-based coating composition, and further treating the filler dispersion containing- polymer based composition at 80-85° C.
13. The method of claim 3 , wherein the trialkoxysilane and monomer are in a weight ratio from 1:2 to 2:1.
14. The method of claim 3 , wherein the initiator is less than 1 wt % of the polymer-based coating composition.
15. The method of claim 12 , wherein the inorganic filler is 0.1-20 wt % of the polymer-based coating composition.
16. The method of claim 3 , wherein the trialkoxysilane is trimethoxysilyl propyl methacrylate or 3-(triethoxysilyl)propyl methacrylate; the monomer is 2,2,3,3,4,4,5,5,6,6,7,7-dodecafluoroheptyl methacrylate or 2-(perfluorohexyl)ethyl methacrylate; and the initiator is benzoyl peroxide.
17. The method of claim 12 , wherein the solvent comprises ethanol, tetrahydrofuran or dimethylformamide, and the inorganic fillers comprise titanium dioxide, silicon dioxide, mica, silica fumes, talc, kaolin or a combination thereof.
18. The method of claim 3 , further comprising adding a solvent to said copolymer, wherein the solvent comprises ethanol, tetrahydrofuran or dimethylformamide.
19. The method of claim 10 , further comprising dispersing one or more types of inorganic fillers in a solvent under ultrasonic mixing to form a filler dispersion, adding said filler dispersion to the polymer-based coating composition, and further treating the filler dispersion containing- polymer based composition at 80-85° C.
20. The method of claim 10 , further comprising adding one or more silane-containing compounds having concrete penetration capability of more than 5 mm in concete to the polymer-based coating composition.