System For Visual Indication Of Mechanical Damage

• US 20120196373A1
• Filed: 06/24/2011
• Published: 08/02/2012
• Est. Priority Date: 06/25/2010
• Status: Active Grant

• Current Assignee: Board of Trustees of The University of Illinois
• Original Assignee: Board of Trustees of The University of Illinois
• Inventors: Odom, Susan A., Caruso, Mary M., Finke, Aaron D., Jackson, Aaron C., Moore, Jeffrey S., Sottos, Nancy R., White, Scott R.
• Granted Patent: US 8,846,404 B2
• Time in Patent Office: Days
• US Class Current: 436/2
• CPC Class Codes: G01N 21/78 producing a change of colour

Abstract

A self-indicating material system may include a solid polymer matrix having a first color, a first plurality of capsules in the matrix, and a plurality of particles in the matrix. The first plurality of capsules includes a first reactant, and the plurality of particles includes a second reactant, which forms a product when in contact with the first reactant. When a crack forms in the polymer matrix, at least a portion of the first plurality of capsules is ruptured, the first and second reactants form the product in the matrix, and the portion of the polymer matrix containing the product has a second color different from the first color. A self-indicating material system may include a solid polymer matrix, a plurality of capsules in the matrix, and an activator in the matrix, where the polymer matrix includes a first polymer and has a first color, the plurality of capsules includes a polymerizer, and the activator is an activator for the polymerizer. When a crack forms in the polymer matrix, at least a portion of the plurality of capsules is ruptured, the polymerizer and the activator form a second polymer in the crack, and the second polymer has a second color different from the first color.

Claims

1. A self-indicating material system, comprising:

a solid polymer matrix having a first color;

a first plurality of capsules in the matrix, the first plurality of capsules comprising a first reactant; and

a plurality of particles in the matrix, the plurality of particles comprising a second reactant;

where, when a crack forms in the polymer matrix, at least a portion of the first plurality of capsules is ruptured, the first and second reactants form a product in the matrix, and the portion of the polymer matrix containing the product has a second color different from the first color.

2. The system of claim 1, where the plurality of particles comprises the second reactant and an encapsulant.

3. The system of claim 1, where the plurality of particles comprises a second plurality of capsules;

and at least a portion of the second plurality of capsules is ruptured when the crack forms in the polymer matrix.

4. The system of claim 3, where the second plurality of capsules further comprises a solvent.

5. The system of claim 1, where the product comprises conjugated carbon-carbon double bonds.

6. The system of claim 1, where the first reactant is a monomer, the second reactant is an activator for the monomer, and the product is a polymer.

7. The system of claim 6, where the material system further is a self-healing material system.

8. The system of claim 6, where the first reactant comprises cyclooctatetraene, the second reactant comprises a metathesis catalyst, and the product comprises poly(acetylene).

9. The system of claim 8, where the metathesis catalyst comprises the Grubbs-Love catalyst.

10. The system of claim 8, where the plurality of particles comprises the metathesis catalyst and an encapsulant.

11. The system of claim 1, where the first reactant is a charge-transfer donor, the second reactant is a charge-transfer acceptor, and the product is a charge-transfer substance.

12. The system of claim 11, where the first reactant comprises TTF, the second reactant comprises TCNQ, and the product comprises a charge-transfer salt.

13. The system of claim 12, where the crack breaks an electrical connection within the polymer matrix, and

the charge-transfer salt restores the electrical connection.

14. The system of claim 11, where

the first reactant comprises a charge-transfer donor selected from the group consisting of DAP, BIS-DAP and BAT,

the second reactant comprises TCNQ, and

the product comprises a charge-transfer molecule.

15. The system of claim 11, where the first reactant comprises anisole, the second reactant comprises TCNQ, and the product comprises a charge-transfer complex.

16. A self-indicating material system, comprising:

a solid polymer matrix comprising a first polymer and having a first color;

a plurality of capsules in the matrix, the plurality of capsules comprising a polymerizer; and

an activator for the polymerizer in the matrix;

where, when a crack forms in the polymer matrix, at least a portion of the plurality of capsules is ruptured, the polymerizer and the activator form a second polymer in the crack, and the second polymer has a second color different from the first color.

17. The system of claim 16, where the activator is present with an encapsulant as a plurality of particles.

18. The system of claim 16, where the second polymer comprises conjugated carbon-carbon double bonds.

19. The system of claim 16, where the polymerizer comprises cyclooctatetraene, the activator comprises a metathesis catalyst, and the product comprises poly(acetylene).

20. The system of claim 19, where the metathesis catalyst comprises the Grubbs-Love catalyst.

21. The system of claim 16, where the material system further is a self-healing material system.

22. A method of indicating mechanical damage in a solid polymer matrix, comprising:

providing in the solid polymer matrix a first plurality of capsules and a plurality of particles;

where the solid polymer matrix has a first color,

the first plurality of capsules comprises a first reactant, and

the plurality of particles comprises a second reactant;

where, when at least a portion of the first plurality of capsules is ruptured, the first reactant contacts the second reactant in the matrix, and a product is formed from the first and second reactants; and

the portion of the polymer matrix containing the product has a second color different from the first color.

23. A method of indicating mechanical damage in a solid polymer matrix, comprising:

providing in the solid polymer matrix a plurality of capsules and an activator;

where the solid polymer matrix comprises a first polymer and has a first color,

the plurality of capsules comprises a polymerizer, and

the activator is an activator for the polymerizer;

where, when at least a portion of the capsules is ruptured, the polymerizer contacts the activator in the matrix, and a second polymer is formed from the polymerizer and the activator; and

the second polymer has a second color different from the first color.