Structures and Methods for Increasing the Speed of Electroactive Polymers

• US 20070205398A1
• Filed: 03/03/2005
• Published: 09/06/2007
• Est. Priority Date: 03/12/2004
• Status: Active Grant

• Current Assignee: University of Maryland
• Original Assignee: University of Maryland
• Inventors: Smela, Elisabeth, Wang, Xuezheng
• Granted Patent: US 8,383,226 B2
• Time in Patent Office: Days
• US Class Current: 252/500
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: F03G 7/005 Electro-chemical actuators; Actuators having a material for absorbing or desorbing gas, e.g. a metal hydride; Actuators using the difference in osmotic pressure between fluids; Actuators with elements stretchable when contacted with liquid rich in ions, with UV light, with a salt solution
• CPC Class Codes: H01B 1/122 Ionic conductors
• CPC Class Codes: H01M 2300/0082 Organic polymers
• CPC Class Codes: H01M 4/045 Electrochemical coating; Electrochemical impregnation
• CPC Class Codes: H01M 4/0497 Chemical precipitation
• CPC Class Codes: H01M 4/137 Electrodes based on electro-active polymers
• CPC Class Codes: H01M 4/364 as mixtures
• CPC Class Codes: H01M 4/602 Polymers
• CPC Class Codes: H01M 8/0289 Means for holding the electrolyte solid polymer electrolytes H01M8/1018
• CPC Class Codes: H01M 8/10 Fuel cells with solid electrolytes
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/50 Fuel cells
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y10T 428/24273 including aperture
• CPC Class Codes: Y10T 428/249978 Voids specified as micro
• CPC Class Codes: Y10T 428/249979 Specified thickness of void-containing component [absolute or relative] or numerical cell dimension

Abstract

Structures are provided that include electroactive polymers. According to these structures, the electroactive materials have enhanced conductivity in a first direction. Also, the structures include either pores or inclusions. These pores or inclusions are non-parallel to the first direction. In addition, methods for forming structures that include electroactive polymers that have enhanced conductivity in a first direction are provided. These methods allow for pores and/or inclusions to be formed in the electroactive polymers.

Claims

1. A structure, comprising:

an ionic electroactive polymer with at least one of enhanced ion conductivity and enhanced mass conductivity in a first direction; and

a plurality of pores located within the electroactive polymer, wherein at least one pore in the plurality of pores includes at least one section that is non-parallel to the first direction.

2. The structure of claim 1, wherein the electroactive polymer comprises at least one of a conjugated polymer, an ionic polymer metal composite (IPMC), nanotubes, and a gel.

3. The structure of claim 2, wherein the electroactive polymer comprises a polymer selected from at least one family of polymers selected from among polypyrroles, polyanalines, polythiophenes, paraphenylenevinylene and polyacetylene.

4. The structure of claim 1, wherein the electroactive polymer comprises at least one of surfactant molecules, molecules including aromatic rings, and liquid crystals.

5. The structure of claim 1, wherein, in the electroactive polymer, the first direction is substantially parallel to a first surface of the electroactive polymer.

6. The structure of claim 1, wherein at least one pore in the plurality of pores extends from a surface of the polymer to an interior portion thereof.

7. The structure of claim 1, wherein the at least one pore is slanted relative to the first direction.

8. The structure of claim 1, wherein at least one pore in the plurality of pores is substantially perpendicular to the first direction.

9. The structure of claim 1, wherein the at least one pore has a diameter of between 1 nanometer and 1 micrometer.

10. The structure of claim 1, wherein the at least one pore has a diameter of between 10 nanometers and 100 nanometers.

11. The structure of claim 1, wherein the plurality of pores comprise at least one of trenches, stripes, and cross-hatches.

12. A method of manufacturing a composite structure, the method comprising:

forming an electroactive polymer that has enhanced conductivity in a first direction; and

forming a plurality of pores in the electroactive polymer, wherein at least one pore in the plurality of pores includes at least one section that is non-parallel to the first direction.

13. The method of claim 12, wherein the forming step comprises forming a matrix which has the electroactive polymer and inclusions, wherein at least one inclusion of the inclusions can be removed from the matrix.

14. The method of claim 12, wherein the forming step comprises forming the electroactive polymer by at least one of casting, dipping, electrodeposition, spin coating, electrodeposition, chemical vapor deposition, evaporation, spinning, and electrospinning.

15. The method of claim 12, wherein forming the plurality of pores comprises forming the plurality of pores in a substantially periodic array.

16. The method of claim 12, wherein forming the plurality of pores comprises forming at least one pore in the plurality of pores to include at least one portion that is substantially perpendicular to the first direction.

17. The method of claim 12, wherein the forming the plurality of pores step comprises forming at least one pore in the plurality of pores to have a diameter of between 1 nanometer and 1 micrometer.

18. The method of claim 12, wherein forming the plurality of pores comprises forming at least one pore in the plurality of pores to have a diameter of between 10 nanometers and 100 nanometers.

19. The method of claim 12, wherein forming the plurality of pores comprises:

forming sacrificial posts;

depositing the electroactive polymer around said posts; and

removing the sacrificial posts.

20. The method of claim 12, wherein forming the plurality of pores comprises:

masking a surface of the electroactive polymer with a mask comprising a set of openings; and

removing portions of the electroactive polymer that are directly below the set of openings.

21. A structure, comprising:

a matrix including an electroactive polymer having enhanced conductivity in a first direction; and

a plurality of inclusions included within the matrix, wherein at least one inclusion in the plurality of inclusions comprises a fast-ion transporting material, and wherein the at least one inclusion comprises a section that is non-parallel to the first direction.

23. The structure of claim 22, wherein the matrix comprises at least one of a conjugated polymer, an ionic polymer metal composite, nanotubes, and a gel.

23-1. The structure of claim 22, wherein the first direction is substantially parallel to a first surface of the electroactive polymer.