LIGHT GENERATING MICROCAPSULES FOR SELF-HEALING POLYMER APPLICATIONS

• US 20190309105A1
• Filed: 06/14/2019
• Published: 10/10/2019
• Est. Priority Date: 06/23/2017
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Campbell, Eric J., Czaplewski-Campbell, Sarah K., Kuczynski, Joseph, Tofil, Timothy J.
• Granted Patent: US 10,696,761 B2
• Time in Patent Office: Days
• CPC Class Codes: A61K 9/5094 Microcapsules containing magnetic carrier material, e.g. ferrite for drug targeting
• CPC Class Codes: B01J 13/04 by physical processes, e.g. drying, spraying
• CPC Class Codes: B01J 13/14 Polymerisation; cross-linking
• CPC Class Codes: B01J 13/22 Coating
• CPC Class Codes: C07D 321/00 Heterocyclic compounds containing rings having two oxygen atoms as the only ring hetero atoms, not provided for by groups C07D317/00 - C07D319/00
• CPC Class Codes: C08F 2/48 by ultraviolet or visible light
• CPC Class Codes: C08F 20/06 Acrylic acid; Methacrylic acid; Metal salts or ammonium salts thereof
• CPC Class Codes: C08F 20/18 with acrylic or methacrylic acids
• CPC Class Codes: C09B 6/00 Anthracene dyes not provided for above

Abstract

A self-healing polymeric material includes a polymeric matrix material, wherein dispersed within the polymeric matrix material is a mixture of materials that includes monomers and a photoinitiator, and a plurality of light generating microcapsules dispersed in the polymeric matrix material. Each light generating microcapsule encapsulates multiple reactants that undergo a chemiluminescent reaction. The chemiluminescent reaction generates a photon having a wavelength within a particular emission range that is consistent with an absorption range of the photoinitiator.

Claims

1. A self-healing polymeric material comprising:

a polymeric matrix material;

wherein dispersed within the polymeric matrix material is a mixture of materials that includes monomers and a photoinitiator; and

a plurality of light generating microcapsules dispersed in the polymeric matrix material, each light generating microcapsule of the plurality of light generating microcapsules encapsulating multiple reactants that undergo a chemiluminescent reaction, wherein each light generating microcapsule comprises an outer shell and an inner shell,

wherein the chemiluminescent reaction generates a photon having a wavelength within a particular emission range that is consistent with an absorption range of the photoinitiator and wherein the chemiluminescent reaction occurs without rupture of the outer shell of the light generating microcapsules.

2. The self-healing polymeric material of claim 1, wherein a crack in the polymeric matrix material causes migration of the monomers and photoinitiator into the crack.

3. The self-healing polymeric material of claim 2, wherein further propagation of the crack in the polymeric matrix material results in application of a compressive force to a light generating microcapsule of the plurality of light generating microcapsules, the compressive force triggering the chemiluminescent reaction within the light generating microcapsule.

4. The self-healing polymeric material of claim 3, wherein the photon generated within the light generating microcapsule exits the light generating microcapsule into the crack to trigger the photoinitiator to initiate a polymerization reaction of the monomers within the crack, the polymerization reaction resulting in formation of a polymeric material that seals the crack.

5. The self-healing polymeric material of claim 4, wherein the photoinitiator includes a free radical initiator, and wherein the polymerization reaction includes a free radical polymerization reaction.

6. The self-healing polymeric material of claim 1, wherein the monomers include acrylate monomers.

7. The self-healing polymeric material of claim 1, wherein the chemiluminescent reaction includes excitation of a dye from a ground state to an excited state and subsequent release of the photon upon relaxation from the excited state to the ground state.

8. The self-healing polymeric material of claim 7, wherein excitation of the dye is caused by energy released during decomposition of a 1,2-dioxetanedione molecule.

9. The self-healing polymeric material of claim 8, wherein a chemical reaction of a diphenyl oxalate molecule with a hydrogen peroxide molecule results in formation of the 1,2-dioxetanedione molecule.

10. The self-healing polymeric material of claim 7, wherein the dye includes 9,10-diphenylanthracene.

11. The self-healing polymeric matrix material of claim 1, wherein each light generating microcapsule includes a multiple-compartment microcapsule that comprises:

a first compartment that contains a first reactant of the multiple reactants;

a second compartment that contains a second reactant of the multiple reactants; and

wherein the inner shell is an isolating structure separating the first compartment from the second compartment, the isolating structure adapted to rupture in response to application of a compressive force to cause the first reactant and the second reactant to undergo the chemiluminescent reaction.

12. The self-healing polymeric matrix material of claim 11, wherein the multiple-compartment microcapsule includes a shell-in-shell microcapsule and the inner shell is contained within the outer shell, wherein the inner shell encapsulates the first compartment, wherein the outer shell encapsulates the second compartment.

13. The self-healing polymeric matrix material of claim 12, wherein the outer shell comprises a polymer, and wherein the outer shell has a transmittance value of at least 90% for the wavelength within the particular emission range.

14. The self-healing polymeric matrix material of claim 13, wherein the polymer comprises gelatin, arabic gum, shellac, lac, starch, dextrin, wax, rosin, sodium alginate, zein, methyl cellulose, ethyl cellulose, carboxymethyl cellulose, hydroxyethyl ethyl cellulose, polyolefins, polystyrenes, polyethers, polyesters, polyureas, polyethylene glycol, polyamides, polyimides, urea-formaldehydes, polyurethane, polyacrylate, epoxy resins, and combinations thereof.