Reversible self-repairing epoxy resin and preparation and recovery remoulding method therefor

Patent metadata

Field	Value
Publication number	US-11193000-B2
Application number	US-201816759327-A
Country	US
Kind code	B2
Filing date	Feb 27, 2018
Priority date	Feb 27, 2018
Publication date	Dec 7, 2021
Grant date	Dec 7, 2021

Abstract

This invention provides a self-healable epoxy resin and its preparation, recycling and remolding method. With the catalyst of potassium iodide, an ester solution of 2-mercaptoacetic acid was oxidated by 30% H2O2 to form 2,2′-dithiodiacetic acid; then 2,2′-dithiodiacetic acid was dehydrated and cyclizated by anhydride to form 1,4,5-oxadithiepane-2,7-dione; 1,4,5-oxadithiepane-2,7-dione and methylhexahydrophthalic anhydride were mixed by mass ratio and cured with epoxides to get the self-healable epoxy resin. Through controlling dynamic and permanent three-dimensional crosslinked network, the self-healable epoxy resins provided in this invention exhibit high thermal resistance and improved mechanical properties as well as excellent self-healing ability, recyclability and remoldability. This invention provides a preparation method with the merits of low cost, simple production processes, broad application prospects and strong utility.

First claim

The invention claimed is:

1. A method for preparing a self-healable epoxy resin, comprising:
(1) by mass, at 20 to 30° C., 120 parts of 2-mercaptoacetic acid, 500 to 700 parts of ester solvent and 0.6 to 1.2 parts of potassium iodide are mixed homogeneously to obtain a solution; 80 to 90 parts of 30 wt % H 2 O 2 are added dropwise to the solution and continued to react for 2 to 4 h to get 2,2′-dithiodiacetic acid;
(2) by mass, at 20 to 30° C., 100 parts of 2,2′-dithiodiacetic acid and 120 to 150 parts of anhydride are mixed homogeneously and continued to react for 2 to 4 h to get 1,4,5-oxadithiepane-2,7-dione;
(3) by mass, at 50 to 70° C., 100 parts of epoxy resin, 42 to 84 parts of 1,4,5-oxadithiepane-2,7-dione and 0 to 43 parts of methylhexahydrophthalic anhydride are mixed homogeneously, after curing, the self-healable epoxy resin is obtained.

2. The method according to claim 1 , wherein the ester solvent is methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, or any combination thereof, and the anhydride is acetic anhydride, trifluoroacetic anhydride, or any combination thereof.

3. The method according to claim 1 , wherein the epoxy resin is glycidyl ether type epoxy resin, glycidyl ester type epoxy resin, glycidyl amine type epoxy resin, aliphatic epoxides, alicyclic epoxides, or any combination thereof.

Assignees

• Univ Soochow

Inventors

• Liang Guozheng
• Zhang Youhao
• Gu Aijuan
• Yuan Li

Classifications

• C07D327/00 Primary

  Heterocyclic compounds containing rings having oxygen and sulfur atoms as the only ring hetero atoms · CPC title

• C08J2363/00

  Characterised by the use of epoxy resins; Derivatives of epoxy resins · CPC title

• C08G59/423

  containing an atom other than oxygen belonging to a functional groups to C08G59/42, carbon and hydrogen · CPC title

• C08L63/00

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

• C08G59/40

  characterised by the curing agents used · CPC title