Base-mediated method for the recycling of epoxy resin-carbon fiber composites

Patent metadata

Field	Value
Publication number	US-2024158603-A1
Application number	US-202318383458-A
Country	US
Kind code	A1
Filing date	Oct 24, 2023
Priority date	Oct 24, 2022
Publication date	May 16, 2024
Grant date	—

Abstract

Methods, compositions of matter and processes for a base-mediated chemical deconstruction of varying amine-cured epoxy resins into constituent monomer alcohol products and amine materials are disclosed herein.

First claim

We claim:

1 . A method for metal alkoxide base-mediated cleavage of C—O and C—N bonds in amine-cured epoxy resins comprising contacting an amine-cured epoxy resin with a metal alkoxide base.

2 . The method of claim 1 wherein the metal alkoxide base comprises potassium tert-butoxide.

3 . The method of claim 1 wherein a metal hydroxide base is added to the metal alkoxide base wherein the metal hydroxide base is selected from the group consisting of LiOH, NaOH, KOH, Ca(OH) 2 , and Sr(OH) 2 .

4 . The method of claim 1 wherein the cleavage of C—O and C—N bonds in amine-cured epoxy resins yields about 97 percent molar yield of phenols and about 99 percent molar yield of amine products.

5 . The method of claim 1 wherein the metal alkoxide base-mediated cleavage of C—O and C—N bonds in amine-cured epoxy resins occurs at a temperature of from about 140 degrees Celsius to about 160 degrees Celsius.

6 . The method of claim 1 wherein the metal alkoxide base-mediated cleavage of C—O and C—N bonds in amine-cured epoxy resins occurs in a solvent mixture of toluene and dioxane.

7 . The method of claim 1 wherein the metal alkoxide base-mediated cleavage occurs over about 48 hours.

8 . The method of claim 1 further comprising swelling the amine-cured epoxy resin before contacting the resin with the metal alkoxide base.

9 . The method of claim 1 wherein the amine-cured epoxy resin is BADGE.

10 . The method of claim 9 further comprising the step of isolating BPA and aniline as products resulting from the metal alkoxide base-mediated cleavage of C—O and C—N bonds of BADGE.

11 . The method of claim 9 wherein the metal alkoxide base is potassium tert-butoxide.

12 . The method of claim 9 further comprising swelling the BADGE before contacting the BADGE with the metal alkoxide base.

13 . The method of claim 1 wherein the amine-cured epoxy resin is a thermoplastic resin.

14 . The method of claim 13 wherein the metal alkoxide base is potassium tert-butoxide.

15 . The method of claim 13 further comprising swelling the thermoplastic resin before contacting the thermoplastic resin with the metal alkoxide base.

16 . The method of claim 1 wherein the amine-cured epoxy resin is a thermoset resin.

17 . The method of claim 16 wherein the metal alkoxide base is potassium tert-butoxide.

18 . The method of claim 16 wherein the thermoset resin has a glass temperature transition of about 110 degrees Celsius.

19 . The method of claim 16 further comprising isolating resulting monomeric reaction products.

20 . The method of claim 16 further comprising swelling the thermoset resin before contacting the thermoset resin with the metal alkoxide base.

Assignees

• Alliance Sustainable Energy

Inventors

• Dipucchio Rebecca Claire
• Stevenson Katherine Rose
• Beckham Gregg Tyler

Classifications

• C08J11/24 Primary

  containing hydroxyl groups · CPC title

• C07C37/52

  by splitting polyaromatic compounds, e.g. polyphenolalkanes · CPC title

• C08J2363/10

  Epoxy resins modified by unsaturated compounds · CPC title