Water dispersible epoxy urethane compounds and coating compositions

1. An aqueous coating composition comprising a dispersion of:

(a) a polyfunctional oligomer having at least two epoxy urethane functional groups and a C 1 -C 15 alkyl terminated polyalkylene oxide chain; and

(b) water;

wherein said aqueous coating composition does not contain a surfactant,

wherein the polyfunctional oligomer comprises a polyfunctional resin derived from an isocyanurate or a biuret compound.

2. An aqueous coating composition comprising a dispersion of:

(a) 10 to 90 parts of a polyfunctional oligomer having at least two epoxy urethane functional groups and a C 1 -C 15 alkyl terminated polyalkylene oxide chain; and

(b) 90 to 10 parts water;

wherein said aqueous coating composition does not contain a surfactant,

wherein the polyfunctional oligomer comprises a polyfunctional resin derived from an isocyanurate or a biuret compound.

3. An aqueous coating composition of claim 1 or claim 2 , further comprising a curing agent.

4. An aqueous coating composition of claim 3 , wherein the polyfunctional resin is selected from the group consisting of toluene diisocyanate isocyanurate, toluene diisocyanate biuret, diphenylmethane diisocyanate isocyanurate, diphenylmethane diisocyanate biuret, hexamethylene diisocyanate isocyanurate, hexamethylene diisocyanate biuret, naphthalene diisocyanate isocyanurate, naphthalene diisocyanate biuret, hydrogenated diphenylmethane diisocyanate isocyanurate, hydrogenated diphenylmethane diisocyanate biuret, isophorone diisocyanate isocyanurate and isophorone diisocyanate biuret; and

the C 1 -C 15 alkyl terminated polyalkylene oxide is a C 1 -C 10 alkyl terminated polyalkylene oxide and the polyalkylene oxide chain is selected from the group consisting of an ethylene oxide chain, a propylene oxide chain, and an ethylene propylene oxide chain.

5. An aqueous coating composition of claim 3 , wherein the polyfunctional resin is hexamethylene diisocyanate isocyanurate or hexamethylene diisocyanate biuret.

6. An aqueous coating composition of claim 3 , wherein the curing agent is an amine curing agent.

7. An aqueous coating composition of claim 6 , wherein the amine curing agent is selected from the group consisting of bis(para-aminocyclohexyl)methane, diethylene triamine, and 4,4′-methylene dianiline.

8. A method for making a polyfunctional oligomer having at least two epoxy urethane functional groups and a C 1 -C 15 alkyl terminated polyalkylene oxide chain comprising the steps of reacting

(a) methoxy poly(ethylene glycol) with a polyfunctional isocyanate resin derived from an isocyanurate or a biuret compound; and

(b) glycidol with said polyfunctional isocyanate resin.

9. A method for making an aqueous coating composition comprising the step of mixing a polyfunctional oligomer having at least two epoxy urethane functional groups and a C 1 -C 15 alkyl terminated polyalkylene oxide chain and water to form a dispersion,

wherein a surfactant is not added to said aqueous coating composition wherein the polyfunctional oligomer comprises a polyfunctional resin derived from an isocyanurate or a biuret compound.

10. A method for making an aqueous coating composition of claim 9 comprising the step of mixing

(a) 10 to 90 parts of a polyfunctional oligomer having at least two epoxy urethane functional groups and a C 1 -C 15 alkyl terminated polyalkylene oxide chain; and

(b) 90 to 10 parts water.

11. A method for making an aqueous coating composition of claim 9 or 10 , further comprising the step of adding a curing agent to the mixture of the polyfunctional oligomer and water after the dispersion.

12. A method for making an aqueous coating composition of claim 9 or 10 , further comprising, before the mixing step, the step of:

reacting a C 1 -C 15 alkyl terminated polyalkylene oxide modified polyfunctional resin having at least two isocyanates with glycidol to prepare the polyfunctional oligomer.

13. A method for making an aqueous coating composition of claim 9 , wherein the polyfunctional resin is selected from the group consisting of toluene diisocyanate isocyanurate, toluene diisocyanate biuret, diphenylmethane diisocyanate isocyanurate, diphenylmethane diisocyanate biuret, hexamethylene diisocyanate isocyanurate, hexamethylene diisocyanate biuret, naphthalene diisocyanate isocyanurate, naphthalene diisocyanate biuret, hydrogenated diphenylmethane diisocyanate isocyanurate, hydrogenated diphenylmethane diisocyanate biuret, isophorone diisocyanate isocyanurate and isophorone diisocyanate biuret; and

the C 1 -C 15 alkyl terminated polyalkylene oxide is a C 1 -C 10 alkyl terminated polyalkylene oxide and the polyalkylene oxide chain is selected from the group consisting of an ethylene oxide chain, a propylene oxide chain, and an ethylene propylene oxide chain.

14. The method for making an aqueous coating composition of claim 13 , wherein the polyfunctional resin is hexamethylene diisocyanate isocyanurate or hexamethylene diisocyanate biuret.

15. The method for making an aqueous coating composition of claim 11 , wherein the curing agent is amine curing agent.

16. The method for making an aqueous coating composition of claim 15 , wherein the amine curing agent is selected from the group consisting of bis(para-aminocyclohexyl)methane, diethylene triamine, and 4,4′-methylene dianiline.

17. A substrate, article, or surface coated with an aqueous coating composition of claim 1 .

18. An aqueous coating composition of claim 4 , wherein the C 1 -C 10 alkyl terminated polyalkylene oxide is methoxy polyalkylene oxide.

19. A method for making an aqueous coating composition of claim 13 , wherein the C 1 -C 10 alkyl terminated polyalkylene oxide is methoxy polyalkylene oxide.