Electronically reversible adhesive methods

Patent metadata

Field	Value
Publication number	US-10487245-B2
Application number	US-201916253085-A
Country	US
Kind code	B2
Filing date	Jan 21, 2019
Priority date	Sep 15, 2017
Publication date	Nov 26, 2019
Grant date	Nov 26, 2019

Abstract

A method of decoupling an adhesive system from a contact surface of an object is disclosed. The adhesive system has a full adhesive strength in a de-energized state. The adhesive system comprises a backing, carbon nanotubes, each having a first end region, coupled to the backing, and a second end region, opposite the first end region, and charged nanoparticles, each coupled to the second end region of at least one of the carbon nanotubes. The method comprises steps of electrically charging the backing and disengaging the adhesive system from the contact surface. Electrically charging the backing creates an electrical repulsion force between the backing and the charged nanoparticles, so that the full adhesive strength of the adhesive system is decreased to a reduced adhesive strength. Disengaging the adhesive system from the contact surface comprises applying a disengagement force to the adhesive system sufficient to overcome the reduced adhesive strength.

First claim

What is claimed is:

1. A method of decoupling an adhesive system, having a full adhesive strength in a de-energized state, from a contact surface of an object, wherein the adhesive system comprises a backing, carbon nanotubes, each having a first end region, coupled to the backing, and a second end region, opposite the first end region, and charged nanoparticles, each coupled to the second end region of at least one of the carbon nanotubes, the method comprising steps of:
electrically charging the backing to create an electrical repulsion force between the backing and the charged nanoparticles so that the full adhesive strength of the adhesive system is decreased to a reduced adhesive strength; and
disengaging the adhesive system from the contact surface by applying a disengagement force to the adhesive system sufficient to overcome the reduced adhesive strength;
wherein:
each of the charged nanoparticles comprises a core, and
the core comprises one or more of metal, metal alloy, aluminum, copper, tin, zinc, iron, silver, gold, nickel, ceramic, or polymeric material.

2. The method according to claim 1 , wherein the adhesive system is in the de-energized state when the backing is electrically charged.

3. The method according to claim 1 , wherein a net neutral charge is established in the backing to electrically discharge the backing.

4. The method according to claim 1 , wherein the backing is disconnected from any electrical source to electrically discharge the backing.

5. The method according to claim 1 , wherein:
the step of electrically charging the backing comprises creating a backing net electrical charge in the backing; and
the backing net electrical charge and a nanoparticle net electrical charge of each of the charged nanoparticles both have either a negative sign or a positive sign.

6. The method according to claim 1 , wherein the step of electrically charging the backing comprises placing the charged nanoparticles in an electric field that is sufficiently strong to repel the charged nanoparticles from the backing.

7. The method according to claim 1 , wherein the disengagement force acts in a direction, perpendicular to the contact surface.

8. The method according to claim 1 , wherein the disengagement force acts in a direction parallel to the contact surface.

9. The method according to claim 1 , further comprising steps of:
with the adhesive system in the de-energized state and the carbon nanotubes in an intimate contact with the contact surface so that the adhesive system is adhered to the contact surface with the full adhesive strength, electrically charging the backing; and
disengaging the adhesive system from the contact surface.

10. The method according to claim 9 , wherein:
when the adhesive system, in the de-energized state, and the carbon nanotubes in the intimate contact with the contact surface, the adhesive system contacts at least one particulate on the contact surface such that at least the one particulate precludes at least one of the carbon nanotubes of the adhesive system from contacting the contact surface; and
the step of disengaging the adhesive system from the contact surface comprises disengaging the adhesive system from at least the one particulate by applying the disengagement force sufficient to overcome the reduced adhesive strength.

11. The method according to claim 10 , wherein the reduced adhesive strength corresponds to a force that is less than a retention force between at least the one particulate and the contact surface.

12. A method of decoupling an adhesive system, having a full adhesive strength in a de-energized state, from a contact surface of an object, wherein the adhesive system comprises a backing, carbon nanotubes, each having a first end region, coupled to the backing, and a second end region, opposite the first end region, and charged nanoparticles, each coupled to the second end region of at least one of the carbon nanotubes, the method comprising steps of:
electrically charging the backing to create an electrical repulsion force between the backing and the charged nanoparticles so that the full adhesive strength of the adhesive system is decreased to a reduced adhesive strength; and
disengaging the adhesive system from the contact surface by applying to the adhesive system a disengagement force, sufficient to overcome the reduced adhesive strength; and
wherein the backing comprises a conductive layer that is electrically isolated from the carbon nanotubes.

13. The method according to claim 12 , wherein the adhesive system is in the de-energized state when the backing is electrically charged.

14. The method according to claim 12 , wherein a net neutral charge is established in the backing to electrically discharge the backing.

15. The method according to claim 12 , wherein the backing is disconnected from any electrical source to electrically discharge the backing.

16. The method according to claim 12 , wherein:
the step of electrically charging the backing comprises creating a backing net electrical charge in the backing; and
the backing net electrical charge and a nanoparticle net electrical charge of each of the charged nanoparticles both have either a negative sign or a positive sign.

17. The method according to claim 12 , wherein the step of electrically charging the backing comprises placing the charged nanoparticles in an electric field that is sufficiently strong to repel the charged nanoparticles from the backing.

18. The method according to claim 12 , wherein the disengagement force, applied to the adhesive system, acts in a direction, perpendicular to the contact surface of the object.

19. The method according to claim 12 , wherein the disengagement force, applied to the adhesive system, acts in a direction parallel to the contact surface of the object.

20. The method according to claim 12 , further comprising steps of:
with the adhesive system in the de-energized state and the carbon nanotubes in an intimate contact with the contact surface of the object so that the adhesive system is adhered to the contact surface with the full adhesive strength, electrically charging the backing; and
disengaging the adhesive system from the contact surface.

21. The method according to claim 20 , wherein:
with the adhesive system in the de-energized state and the carbon nanotubes in the intimate contact with the contact surface of the object, the adhesive system contacts at least one particulate on the contact surface such that at least the one particulate precludes at least one of the carbon nanotubes of the adhesive system from contacting the contact surface; and
the step of disengaging the adhesive system from the contact surface of the object comprises disengaging the adhesive system from at least the one particulate by applying to the adhesive system the disengagement force sufficient to overcome the reduced adhesive strength.

22. The method according to claim 21 , wherein the reduced adhesive strength corresponds to a force that is less than a retention force between at least the one particulate and the contact surface of the object.

23. A method of decoupling an adhesive system, having a full adhesive strength in a de-energized state, from a contact surface of an object, wherein the adhesive system comprises a backing, carbon nanotubes, each having a first end region, coupled to the backing, and a second end region, opposite the first end region, and charged nanoparticles, each c

Assignees

• Boeing Co

Inventors

• Humfeld Keith Daniel
• Hartshorn Scott D

Classifications

• C09J7/00

  Adhesives in the form of films or foils · CPC title

• B82Y30/00

  Nanotechnology for materials or surface science, e.g. nanocomposites · CPC title

• C09J2400/10

  Presence of inorganic materials · CPC title

• C09J9/02 Primary

  Electrically-conducting adhesives · CPC title

• B32B43/006

  Delaminating · CPC title