Polyamides and amidoamines derived from hydroxyalkylpolyamines: epoxy curing agents with improved properties

Patent metadata

Field	Value
Publication number	US-11530293-B2
Application number	US-201716470510-A
Country	US
Kind code	B2
Filing date	Dec 15, 2017
Priority date	Dec 19, 2016
Publication date	Dec 20, 2022
Grant date	Dec 20, 2022

Abstract

Polyamide and amidoamine curing agents comprising a selectively modified amine. The selectively modified amine is formed by a substitution reaction between a polyamine and an epoxide, resulting in a multifunctional amine having a hydroxyl substituent. The curing agents are used to form epoxy resins having improved properties when cured.

First claim

What is claimed:

1. A curing agent comprising the reaction product of
(1) an amine component comprising at least one selectively modified multifunctional amine, and
(2) a fatty acid component comprising a mixture of tall oil fatty acid derived dimer acid and tall oil fatty acid;
wherein the at least one selectively modified multifunctional amine comprises a compound having a structural formula selected from the group consisting of:

wherein the fatty acid component comprises at least one dimeric acid, at least one trimeric acid and at least one mono acid, wherein the dimeric acid comprises about 50 wt % to about 95 wt % of the fatty acid component, wherein the trimeric acid comprises about 3 wt % to about 40 wt % of the fatty acid component, and wherein the mono acid comprises less than 5 wt % of the fatty acid component; and wherein the curing agent has an imidazoline to amide ratio between about 2.3:1 and about 3.2:1.

2. The curing agent of claim 1 , wherein a viscosity of the curing agent ranges from about 6000 MPa s to about 100,000 MPa s.

3. The curing agent of claim 1 wherein the at least one selectively modified multifunctional amine comprises hydroxyethyl polyethylenepolyamine.

4. The curing agent of claim 1 wherein the amine component comprises at least one unmodified polyalkylamine.

5. The curing agent of claim 1 wherein the fatty acid component comprises monocarboxylic acids containing from about 8 to about 20 carbon atoms and from about 0 to about 4 units of unsaturation.

6. The curing agent of claim 1 wherein the ratio of the fatty acid component to the amine component ranges from about 1:1 to about 2:1, on a molecular basis, for monomeric fatty acids.

7. The curing agent of claim 1 wherein the reaction product comprises amidoamine compounds having the general structure:

where R represents an alkyl or aryl group of 1-30 carbon atoms, and where X and Y are independently selected from (R1-NH—R2) m , where m=1 to 3, and R1, R2=alkylene groups of at least one C atom.

8. The curing agent of claim 1 wherein the reaction product comprises polyamide compounds having the general structure:

where A and B are, independently, alkyl or aryl groups of 1-30 carbon atoms, and where X and Y are independently selected from (R1-NH—R2) m , where m=1 to 3, and R1, R2=alkylene groups of at least one C atom.

9. An amine-epoxy composition comprising the reaction product of:
(1) the curing agent of claim 1 ; and
(2) an epoxy composition comprising at least one multi-functional epoxy resin.

10. The amine-epoxy composition of claim 9 , wherein the epoxy composition further comprises at least one polyepoxy compound.

11. The amine-epoxy composition of claim 10 wherein the at least one polyepoxy compound comprises at least one of the diglycidyl ethers of bisphenol-A, the advanced diglycidyl ethers of bisphenol-A, the diglycidyl ethers of bisphenol-F, and the epoxy novolac resins.

12. The amine-epoxy composition of claim 9 , wherein the stoichiometric ratios of epoxy groups to amine hydrogen ranges from about 1.5 to 1 to about 1 to 1.5.

13. The amine-epoxy composition of claim 10 , wherein the at least one polyepoxy compound comprises at least one dihydric phenol of the following structure:

where m is 0 to 7, and R is a divalent hydrocarbon radical of a dihydric phenol.

14. An article of manufacture comprised of the amine-epoxy composition of claim 9 .

15. A method for forming a curing agent, comprising:
(i) reacting (1) at least one selectively modified multifunctional amine, with (2) a fatty acid component comprising a mixture of tall oil fatty acid derived dimer acid and tall oil fatty acid, wherein the at least one selectively modified multifunctional amine comprises a compound having a structural formula selected from the group consisting of:

wherein the fatty acid component comprises at least one dimeric acid, at least one trimeric acid and at least one mono acid, wherein the dimeric acid comprises about 50 wt % to about 95 wt % of the fatty acid component, wherein the trimeric acid comprises about 3 wt % to about 40 wt % of the fatty acid component, and wherein the mono acid comprises less than 5 wt % of the fatty acid component; and wherein the curing agent has an imidazoline to amide ratio between about 2.3:1 and about 3.2:1.

16. The method of claim 15 , further comprising adding a defoamer.

Assignees

• Evonik Operations Gmbh

Inventors

• Lal Gauri Sankar
• Ananthachar Sudhir
• Boyce Stephen Michael

Classifications

• C08G69/34 Primary

  using polymerised unsaturated fatty acids · CPC title

• C08G59/54 Primary

  Amino amides> · CPC title

• C08G69/44

  Polyester-amides · CPC title

• C08G73/028

  Polyamidoamines · CPC title

• C08G59/44 Primary

  Amides · CPC title