Extended pot-life for low temperature curing polyuretdione resins

Patent metadata

Field	Value
Publication number	US-10633477-B2
Application number	US-201815933553-A
Country	US
Kind code	B2
Filing date	Mar 23, 2018
Priority date	Mar 23, 2018
Publication date	Apr 28, 2020
Grant date	Apr 28, 2020

Abstract

The present invention provides a reaction mixture comprising a polyuretdione resin, a neutralized polyol, an acid-blocked tertiary amine catalyst, and optionally, an additive package selected from the group consisting of flow control additives, and wetting agents, and solvents, wherein the acid has a pK a of greater than 4.82. Compositions made from the reaction mixture of the present invention may be catalyzed at temperatures from room temperature to 130° C. and are particularly applicable in or as coatings, adhesives, castings, composites, and sealants with good performance and extended pot-life.

First claim

What is claimed is:

1. A reaction mixture comprising:
a polyuretdione resin;
a neutralized polyol; and
an acid-blocked tertiary amine catalyst;
a hydrocarbon solvent; and
optionally,
an additive package selected from the group consisting of flow control additives, and wetting agents,
wherein the acid has a pK a of greater than 4.82.

2. The reaction mixture according to claim 1 , wherein the polyuretdione resin comprises the reaction product of catalytic dimerization of an isocyanate.

3. The reaction mixture according to claim 2 , wherein the isocyanate is selected from the group consisting of 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate (HDI), 2,2,4-trimethyl-1,6-hexamethylene diisocyanate, 1,12-dodecamethylene diisocyanate, cyclohexane-1,3- and 1,4-diisocyanate, 1-isocyanato-2-isocyanato-methyl cyclopentane, 1-isocyanato-3-isocyanatomethyl-3,5,5-trimethyl cyclohexane (isophorone diisocyanate or IPDI), bis-(4-isocyanatocyclohexyl)methane, 1,3- and 1,4-bis(isocyanatomethyl)-cyclohexane, bis-(4-isocyanato-3-methyl-cyclohexyl)-methane, α,α,α′,α′-tetramethyl-1,3- and 1,4-xylene diisocyanate, 1-isocyanato-1-methyl-4(3)-isocyanato-methyl cyclohexane, and 2,4- and 2,6-hexahydrotoluene diisocyanate, toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), pentane diisocyanate (PDI)—bio-based, and, isomers of any of these.

4. The reaction mixture according to claim 1 , wherein the acid blocked tertiary amine catalyst comprises an amidine.

5. The reaction mixture according claim 1 , wherein the acid-blocked tertiary amine comprises one of 1,8-diazabicyclo[5.4.0]undec-7ene, 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene, 1,4,5,6-tetrahydro-1,2-dimethylpyrimidine, sodium-1,2,4-triazolide and 2-tert-butyl-1,1,3,3-tetramethylguanidine, and combinations thereof.

6. The reaction mixture according to claim 1 , wherein the acid is selected from the group consisting of formic, acetic, propionic, butyric, caproic, carbolic, 2-ethyl-hexanoic, caprylic, cyanoacetic, pyruvic, benzoic, oxalic, malonic, succinic, phthalic, salicylic and maleic acid, and combinations thereof.

7. The reaction mixture according to claim 1 , wherein the acid has a pK a of greater than 5.0.

8. The reaction mixture according to claim 1 , wherein the acid has a pK a of greater than 5.5.

9. The reaction mixture according to claim 1 , wherein the acid has a pK a of from greater than 4.82 to 10.

10. The reaction mixture according to claim 1 , wherein the neutralized polyol comprises the reaction product of a polyol and an acid scavenger.

11. The reaction mixture according to claim 10 , wherein the acid scavenger is covalently bonded to acidic groups within the polyol and is selected from the group consisting of carbodiimides, anhydrides, epoxies, trialkylorthoformates, amine compounds, and oxazolines, and combinations thereof.

12. The reaction mixture according to claim 1 , wherein the acid comprises a mono- or dicarboxylic acid having 1-20 carbon atoms.

13. The reaction mixture according to claim 1 , wherein the polyol is selected from the group consisting of polyether polyols, polyester polyols, hydroxy-containing (meth)acrylic polymers and (meth)acrylic polyols, polyurethane polyols, polycarbonate polyols and polycaprolactone polyols, and combinations thereof.

14. One of a coating, an adhesive, a casting, a composite, and a sealant comprising the reaction mixture according to claim 1 .

15. A method of making a composition comprising: reacting a polyuretdione resin and a neutralized polyol, in the presence of an acid-blocked tertiary amine catalyst and a hydrocarbon solvent, wherein the acid has a pK a of greater than 4.82 and wherein reaction optionally includes an additive package selected from the group consisting of flow control additives, and wetting agents.

16. The method according to claim 15 , wherein the polyuretdione resin comprises the reaction product of catalytic dimerization of an isocyanate.

17. The method according to claim 16 , wherein the isocyanate is selected from the group consisting of 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate (HDI), 2,2,4-trimethyl-1,6-hexamethylene diisocyanate, 1,12-dodecamethylene diisocyanate, cyclohexane-1,3- and 1,4-diisocyanate, 1-isocyanato-2-isocyanato-methyl cyclopentane, 1-isocyanato-3-isocyanatomethyl-3,5,5-trimethyl cyclohexane (isophorone diisocyanate or IPDI), bis-(4-isocyanatocyclohexyl)methane, 1,3- and 1,4-bis(isocyanatomethyl)-cyclohexane, bis-(4-isocyanato-3-methyl-cyclohexyl)-methane, α,α,α′,α′-tetramethyl-1,3- and 1,4-xylene diisocyanate, 1-isocyanato-1-methyl-4(3)-isocyanato-methyl cyclohexane, and 2,4- and 2,6-hexahydrotoluene diisocyanate, toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), pentane diisocyanate (PDI) bio-based, and, isomers of any of these.

18. The method according to claim 15 , wherein the acid blocked tertiary amine catalyst comprises an amidine.

19. The method according to claim 15 , wherein the acid-blocked tertiary amine catalyst comprises one of 1,8-diazabicyclo[5.4.0]undec-7ene, 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene, 1,4,5,6-tetrahydro-1,2-dimethylpyrimidine, sodium-1,2,4-triazolide and 2-tert-butyl-1,1,3,3-tetramethylguanidine, and combinations thereof.

20. The method according to claim 15 , wherein the acid is selected from the group consisting formic, acetic, propionic, butyric, caproic, carbolic, 2-ethyl-hexanoic, caprylic, cyanoacetic, pyruvic, benzoic, oxalic, malonic, succinic, phthalic, salicylic and maleic acid, and combinations thereof.

21. The method according to claim 15 , wherein the acid has a pK a of greater than 5.0.

22. The method according to claim 15 , wherein the acid has a pK a of greater than 5.5.

23. The method according to claim 15 , wherein the acid has a pK a of from greater than 4.82 to 10.

24. The method according to claim 15 , wherein the neutralized polyol comprises the reaction product of a polyol and an acid scavenger.

25. The method according to claim 24 , wherein the acid scavenger is covalently bonded to acidic groups within the polyol and is selected from the group consisting of carbodiimides, anhydrides, epoxies, trialkylorthoformates, amine compounds, and oxazolines, and combinations thereof.

26. The method according to claim 15 , wherein the acid comprises a mono- or dicarboxylic acid having 1-20 carbon atoms.

27. The method according to claim 15 , wherein the polyol is selected from the group consisting of polyether polyols, polyester polyols, hydroxy-containing (meth)acrylic polymers and (meth)acrylic polyols, polyurethane polyols, polycarbonate polyols and polycaprolactone polyols, and combinations thereof.

28. The method according to claim 16 , wherein reaction of the polyuretdione resin and the polyol occurs in the presence of the acid-blocked tertiary amine catalyst at a temperature of between 20° C. to 130° C.

29. One of a coating, an adhesive, a casting, a composite, and a sealant comprising a composition made according to the method of claim 15 .

Assignees

• Covestro Llc
• Covestro Deutschland Ag

Inventors

• Ekin Alan
• Zielinski David P

Classifications

• C08G18/027 Primary

  the polymeric products containing urethodione groups · CPC title

• C08G18/2036

  having at least three nitrogen atoms in the ring · CPC title

• C08G18/4277

  Caprolactone and/or substituted caprolactone · CPC title

• C08K2201/012

  Additives improving oxygen scavenging properties · CPC title

• C08G18/6229

  Polymers of hydroxy groups containing esters of acrylic or methacrylic acid with aliphatic polyalcohols · CPC title