Storage stable one component polyurethane system

Abstract

In one aspect, the invention relates to storage-stable and flowable polyurethane compositions comprising (a) one or more isocyanate-terminated polyurethane prepolymers derived from one or more hydrocarbon ring-containing diisocyanates and/or triisocyanates and one or more polyols; (b) one or more metal salt complexes of methylenedianiline; and (c) one or more organic acid halide compounds having one or more acid halide groups, wherein the one or more organic acid halide compounds are in an amount wherein the acid halide groups are present in a minimum concentration of about 100 parts per million by weight of the polyurethane prepolymer. In other aspects, the invention relates to methods for storing the curable polyurethane compositions, as well as methods for producing polyurethane elastomers.

Description

Claims

1. A storage-stable flowable polyurethane composition comprising: (a) one or more isocyanate-terminated polyurethane prepolymers derived from one or more hydrocarbon ring-containing diisocyanates and/or triisocyanates and one or more polyols;(b) one or more metal salt complexes of methylenedianiline; and(c) one or more organic acid halide compounds having one or more acid halide groups, wherein said one or more organic acid halide compounds are in an amount wherein said acid halide groups are present in a minimum concentration of about 100 parts per million by weight of the polyurethane prepolymer.

2. The polyurethane composition according to claim 1, wherein the acid halide groups are present in a maximum concentration of about 10,000 parts per million by weight of the polyurethane prepolymer.

3. The polyurethane composition according to claim 1, wherein the polyurethane prepolymer is derived from one or more hydrocarbon ring-containing diisocyanates selected from the group consisting of methylene diphenyl diisocyanate, paraphenylene diisocyanate, toluene diisocyanate, and combinations thereof, and one or more polyols.

4. The polyurethane composition according to claim 1, wherein the metal salt complex of methylenedianiline is a sodium chloride complex of methylenedianiline.

5. The polyurethane composition according to claim 1, wherein the metal salt complex of methylenedianiline is dispersed in an inert organic carrier.

6. The polyurethane composition according to claim 1, wherein no dioctyl phthalate is present.

7. The polyurethane composition according to claim 1, wherein the one or more organic acid halide compounds are selected from the group consisting of organic acid halide compounds having an atmospheric boiling point of at least about 220° C.

8. The polyurethane composition according to claim 6, wherein the one or more organic acid halide compounds are selected from the group consisting of isomers of phthaloyl chloride.

9. A method for storing a curable polyurethane composition, the method comprising storing the curable polyurethane composition for at least about ninety days at a temperature of about 35° C., or at least about thirty days at a temperature greater than 35° C. and up to about 50° C., or at least about seven days at a temperature of about 50° C. to about 70° C., wherein the curable polyurethane composition remains flowable and non-elastomeric during storage as determined at 50° C. during storage, the polyurethane composition comprising: (a) one or more isocyanate-terminated polyurethane prepolymers derived from one or more hydrocarbon ring-containing diisocyanates and/or triisocyanates and one or more polyols;(b) one or more metal salt complexes of methylenedianiline; and(c) optionally, one or more organic acid halide compounds having one or more acid halide groups, wherein said one or more organic acid halide compounds are in an amount wherein said acid halide groups are present in a minimum concentration of about 100 parts per million by weight of the polyurethane prepolymer;provided that when one or more organic acid halide compounds are not present or present in an amount corresponding to an acid halide group concentration of below about 100 parts per million by weight of the polyurethane prepolymer, then the polyurethane prepolymer contains a reduced amount of free diisocyanate and/or triisocyanate monomer.

10. The method according to claim 9, wherein the curable polyurethane composition is stored as a flowable composition, as determined at 50° C., for at least about 180 days at a temperature of about 35° C., or at least about forty-five days at a temperature greater than 35° C. and up to about 50° C., or at least about fourteen days at a temperature of about 50° C. to about 70° C.

11. The method according to claim 9, wherein the polyurethane composition during storage has a viscosity below 100,000 centipoise at 50° C.

12. The method according to claim 9, wherein the polyurethane prepolymer is derived from one or more hydrocarbon ring-containing diisocyanates selected from the group consisting of methylene diphenyl diisocyanate, paraphenylene diisocyanate, toluene diisocyanate, and combinations thereof.

13. The method according to claim 9, wherein the free diisocyanate and/or triisocyanate monomer is in an amount of less than 0.5 percent by weight of polyurethane prepolymer derived from toluene diisocyanate or paraphenylene diisocyanate, and less than four percent by weight of polyurethane prepolymer derived from methylene diphenyl diisocyanate.

14. The method according to claim 9, wherein the metal salt is sodium chloride.

15. The polyurethane composition according to claim 9, wherein the metal salt complex of methylenedianiline is dispersed in an inert organic carrier.

16. The method according to claim 12, wherein the inert organic carrier is dioctyl adipate.

17. The method according to claim 9, wherein no dioctyl phthalate is present.

18. A method for storing a curable polyurethane composition, the method comprising storing the curable polyurethane composition for at least about ninety days at a temperature of about 35° C., or at least about thirty days at a temperature greater than 35° C. and up to about 50° C., or at least about seven days at a temperature of about 50° C. to about 70° C., wherein the curable polyurethane composition remains flowable and non-elastomeric as determined at 50° C. during storage, the polyurethane composition comprising: (a) one or more isocyanate-terminated polyurethane prepolymers derived from one or more hydrocarbon ring-containing diisocyanates and/or triisocyanates and one or more polyols; and(b) one or more metal salt complexes of methylenedianiline.

19. A method for producing a polyurethane elastomer product, the method comprising heating to a temperature in the range of about 100° C. to 150° C. a storage-stable polyurethane composition comprising: (a) one or more isocyanate-terminated polyurethane prepolymers derived from diisocyanate monomers selected from the group consisting of methylene diphenyl diisocyanate, paraphenylene diisocyanate, toluene diisocyanate, and combinations thereof, and one or more polyols;(b) one or more metal salt complexes of methylenedianiline; and(c) one or more organic acid halide compounds having one or more acid halide groups, wherein said one or more organic acid halide compounds are in an amount wherein said acid halide groups are present in a minimum concentration of about 100 parts per million by weight of the polyurethane prepolymer.

20. A polyurethane elastomer product produced by a method comprising heating to a temperature in a range of about 100° C. to 150° C. a storage-stable polyurethane composition comprising: (a) one or more isocyanate-terminated polyurethane prepolymers derived from diisocyanate monomers selected from the group consisting of methylene diphenyl diisocyanate, paraphenylene diisocyanate, toluene diisocyanate, and combinations thereof, and one or more polyols;(b) one or more metal salt complexes of methylenedianiline; and(c) one or more organic acid halide compounds having one or more acid halide groups, wherein said one or more organic acid halide compounds are in an amount wherein said acid halide groups are present in a minimum concentration of about 100 parts per million by weight of the polyurethane prepolymer.