Toughening of epoxy thermosets

Patent metadata

Field	Value
Publication number	US-10428175-B2
Application number	US-201515507532-A
Country	US
Kind code	B2
Filing date	Sep 11, 2015
Priority date	Sep 12, 2014
Publication date	Oct 1, 2019
Grant date	Oct 1, 2019

Abstract

Grafted triglycerides comprising a triglyceride grafted with a fatty acid residue containing 4 to 30 carbon atoms are reacted with an epoxide resin and an amine curing agent to yield an epoxy thermoset. The grafted triglyceride is prepared by reaction of an epoxidized triglyceride with a fatty acid. By varying the length of the fatty residue, the number of fatty residues per triglyceride, the identity of the epoxy resin and the amine curing agent, it is possible to prepare epoxy thermosets that exhibit superior physical properties compared to the properties of epoxy thermosets prepared without the grafted triglyceride, or as compared to epoxy thermosets wherein the epoxidized triglyceride is used in place of the grafted triglyceride.

First claim

What is claimed is:

1. An epoxy thermoset prepared by reaction of:
(a) a grafted triglyceride prepared by reacting a fatty acid that contains from about 4 to about 30 carbon atoms per molecule directly with an epoxidized triglyceride such that 10-100% of the epoxy groups of the epoxidized triglyceride are reacted with the carboxylic acid group of the fatty acid, said epoxidized triglyceride optionally containing one or more carbon-carbon double bonds which were not converted to epoxy groups during epoxidation of the triglyceride, and said optional one or more carbon-carbon double bonds are the only double bonds present in the epoxidized triglyceride when reacted with said fatty acid;
(b) an epoxy resin; and
(c) an amine curing agent;

wherein the weight ratio of the grafted triglyceride to the epoxy resin is in the range of 1:99 to 99:1.

2. The epoxy thermoset of claim 1 , wherein a molar ratio of the fatty acid to the epoxidized triglyceride is from about 0.1:1 to about 4:1.

3. The epoxy thermoset of claim 1 , wherein a molar ratio of the fatty acid to the epoxidized triglyceride is from about 1:1 to about 3.5:1.

4. The epoxy thermoset of claim 1 , wherein a molar ratio of the fatty acid to the epoxidized triglyceride is from about 2:1 to about 3:1.

5. The epoxy thermoset of claim 1 , wherein the grafted triglyceride has a molecular weight of from about 990 g/mole to about 3280 g/mole.

6. The epoxy thermoset of claim 1 , wherein the grafted triglyceride has a molecular weight of from about 1200 g/mole to about 2000 g/mole.

7. The epoxy thermoset of claim 1 , wherein the triglyceride is obtained from a material selected from a plant oil, an animal oil, an algae oil, and a mixture thereof.

8. The epoxy thermoset of claim 1 , wherein the grafted triglyceride comprises one or more epoxy groups.

9. The epoxy thermoset of claim 1 , wherein the epoxy resin is selected from bisphenol A epoxy resin, bisphenol F epoxy resin, novolac epoxy resin, aliphatic epoxy resin, and glycidylamine epoxy resin.

10. The epoxy thermoset of claim 1 , wherein the epoxy resin is a bisphenol-A diglycidyl ether epoxy resin monomer or an oligomer thereof.

11. The epoxy thermoset of claim 1 , wherein the fatty acid is selected from n-hexanoic acid, n-octanoic acid, n-decanoic acid, n-dodecanoic acid, lauric acid, n-tetradecanoic acid, myristic acid, n-hexadecanoic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, linolenic acid, arachidic acid, gadoleic acid, behenic acid and erucic acid.

12. The epoxy thermoset of claim 1 , wherein the weight ratio of the triglyceride to the epoxy resin is in the range of 1:99 to 30:70.

13. The epoxy thermoset of claim 1 , wherein the fatty acid contains 5 to 20 carbon atoms per molecule.

14. The epoxy thermoset of claim 1 , wherein the fatty acid contains 6 to 16 carbon atoms per molecule.

15. The epoxy thermoset of claim 1 , wherein a 5 millimeter thick sample of the epoxy thermoset is translucent.

16. A composite comprising the epoxy thermoset of claim 1 .

17. A composite as claimed in claim 16 comprising one or more materials selected from fibers, reinforcing materials, clays, silicates, fillers and whiskers.

18. A composite as claimed in claim 16 comprising one or more additives selected from colorants, pigments, carbon black, impact modifiers, antioxidants, stabilizers, flame retardants, reheating aids, crystallization aids, oxygen scavengers, plasticizers, flexibilizers, nucleating agents, foaming agents, and mold release agents.

19. An epoxy thermoset prepared by reaction of:
(a) a grafted triglyceride prepared by reacting epoxy groups of an epoxidized triglyceride with a carboxylic acid group of a fatty acid containing from about 4 to about 30 carbon atoms per molecule, such that 10-100% of the epoxy groups of the epoxidized triglyceride are reacted with the carboxylic acid group of the fatty acid; and wherein all of the reacted epoxy groups of the grafted triglyceride have been reacted with the carboxylic acid group of the fatty acid;
(b) an epoxy resin; and
(c) an amine curing agent;

wherein the weight ratio of the grafted triglyceride to the epoxy resin is in the range of 1:99 to 99:1.

Assignees

• Univ Drexel
• Us Army
• Palmese Giuseppe R
• Hu Fengshuo
• Geng xing
• La Scala John J
• The United States Of America Represented By The Secretary Of The Army

Inventors

• Palmese Giuseppe R
• Hu Fengshuo
• Geng xing
• La Scala John J

Classifications

• C08K3/013

  Fillers, pigments or reinforcing additives · CPC title

• C08L63/00

  Compositions of epoxy resins; Compositions of derivatives of epoxy resins · CPC title

• C08K3/00

  Use of inorganic substances as compounding ingredients · CPC title

• C08G59/145 Primary

  Compounds containing one epoxy group · CPC title

• C09D163/00

  Coating compositions based on epoxy resins; Coating compositions based on derivatives of epoxy resins · CPC title