Paints and coatings containing cyclodextrin additives
View Patent ↗Hydrophilic coating compositions and methods to make and use the compositions are disclosed. The coatings include one or more amphiphilic cyclodextrins, with one or more hydrophilic groups in place of primary hydroxyl groups, and one or more hydrophobic groups in place of secondary hydroxyl groups. The hydrophobic surface of the cyclodextrin faces the binder particles, while the hydrophilic surface is exposed to the exterior, thus providing a hydrophilic and self-cleaning property to the coating.
1. A hydrophilic coating composition comprising:
at least one binder; and
a coating additive which is at least one cyclodextrin compound having formula I:
wherein:
each R 1 is, independently, a hydrophobic group or H, where the hydrophobic group is selected from alkenyl, alkynyl, haloalkyl, cycloalkyl, aryl, and any combination thereof, and wherein at least one R 1 is a hydrophobic group;
each R 2 is, independently, a hydrophobic group or H, where the hydrophobic group is selected from alkenyl, alkynyl, haloalkyl, cycloalkyl, aryl, and any combination thereof, and wherein at least one R 2 is a hydrophobic group;
each R 3 is, independently, a hydrophilic group or H, where the hydrophilic group is selected from an amine, an amide, an epoxide, a lactone, a carboxyl, a carbonyl, and any combination thereof, and wherein at least one R 3 is a hydrophilic group; and
n is 6, 7, or 8.
2. The composition of claim 1 , wherein the binder comprises one or more silicone polymers or one or more organic polymers, or any combination thereof.
3. The composition of claim 1 , wherein the cyclodextrin compound is present in about 0.5 weight percent to about 40 weight percent of the total coating composition.
4. The composition of claim 1 , further comprising one or more of a solvent, a coalescing agent, a pigment, a rheology modifier, a plasticizer, and a surfactant.
5. The composition of claim 1 , wherein the coating composition is a decorative coating, an industrial coating, a protective coating, or a self-cleaning coating, or any combination thereof.
6. The composition of claim 1 , wherein the binder comprises inorganic binder selected from potassium silicate, sodium silicate, lithium silicate, and any combination thereof.
7. The composition of claim 1 , wherein each R 1 is independently aryl or haloalkyl.
8. The composition of claim 1 , wherein each R 2 is independently aryl or haloalkyl.
9. The composition of claim 1 , wherein each R 3 is independently carboxyl or epoxide.
10. The composition of claim 1 , wherein each R 1 is alkenyl, each R 2 is alkenyl, and each R 3 is an amine.
11. The composition of claim 1 , wherein each R 1 is alkenyl, each R 2 is aryl, and each R 3 is an epoxide.
12. A method of coating a substrate, the method comprising:
applying a coating composition to the substrate, wherein the coating composition comprises at least one cyclodextrin compound of formula I:
wherein:
each R 1 is, independently, a hydrophobic group or H, where the hydrophobic group is selected from alkenyl, alkynyl, haloalkyl, cycloalkyl, aryl, and any combination thereof, and wherein at least one R 1 is a hydrophobic group;
each R 2 is, independently, a hydrophobic group or H, where the hydrophobic group is selected from alkenyl, alkynyl, haloalkyl, cycloalkyl, aryl, and any combination thereof, and wherein at least one R 2 is a hydrophobic group;
each R 3 is, independently, a hydrophilic group or H, where the hydrophilic group is selected from an amine, an amide, an epoxide, a lactone, a carboxyl, a carbonyl, and any combination thereof, and wherein at least one R 3 is a hydrophilic group; and
n is 6, 7, or 8.
13. The method of claim 12 , wherein applying the coating comprises applying a coating composition having the cyclodextrin compound in about 0.5 weight percent to about 40 weight percent of the total coating composition.
14. The method of claim 12 , wherein applying the coating comprises applying a coating composition further comprising one or more of a binder, a solvent, a coalescing agent, a pigment, a rheology modifier, a plasticizer, and a surfactant.
15. The method of claim 12 , wherein applying the coating comprises coating, brushing, dipping, spraying, rolling, or any combination thereof.