Solventless methods of coating a carbon nanotube network and carbon nanotube networks coated with a polymer

• US 10,358,562 B2
• Filed: 07/27/2017
• Issued: 07/23/2019
• Est. Priority Date: 05/14/2009
• Status: Active Grant

• Current Assignee: Battelle Memorial Institute
• Original Assignee: Battelle Memorial Institute
• Inventors: Palmer, Katherine M., Heintz, Amy M., Burton, Brett R., Feier, Ioan I., Lastrapes, Timothy J.
• Primary Examiner(s): Tschen, Francisco W
• Application Number:
  US15/662,177
• Publication Number:
  US 20180037756A1
• Time in Patent Office: 726 Days
• Field of Search: None
• CPC Class Codes: C08K 3/04 Carbon
• CPC Class Codes: C08K 9/08 Ingredients agglomerated by treatment with a binding agent
• CPC Class Codes: C09D 5/00 Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced electrically insulating plastics, resins or waxes H01B3/30; Filling pastes
• CPC Class Codes: C09D 5/24 Electrically-conducting paints conductive materials H01B1/00
• CPC Class Codes: C09D 7/62 modified by treatment with other compounds
• CPC Class Codes: C09D 7/65 macromolecular C09D7/41-C09D7/48 take precedence
• CPC Class Codes: C09D 7/70 characterised by shape, e.g. fibres, flakes or microspheres
• CPC Class Codes: H01B 1/04 mainly consisting of carbon-silicon compounds, carbon or silicon
• CPC Class Codes: H05B 2214/00 Aspects relating to resistive heating, induction heating and heating using microwaves, covered by groups H05B3/00, H05B6/00
• CPC Class Codes: H05B 2214/03 Heating of hydrocarbons

Abstract

A method of coating a carbon nanotube material with a solventless coating composition is described. The resulting coating has been shown to preserve the conductivity of the conductive layer and protect the conductive layer from the effects of subsequent coating compositions. Examples are shown in which the coating formulation comprises a polyol and an isocyanate. A layer material comprising a polyurethane coating on a carbon nanotube network layer is also described.

Claims

1. A layered CNT-containing article, comprising:

a substrate;

a conductive carbon nanotube (CNT) network layer disposed between the substrate and a polyurethane coating having a thickness of between 0.250 μ

m and 150 μ

m;

wherein the polyurethane coating is in direct contact with the CNT layer; and

further wherein the underlying conductive CNT network layer comprises 50 mass % or less of the coating polymer within the layer and has a sheet resistance of 120 Ω

/square or less, and wherein the CNT layer is substantially free from N-groups that are associated with the topcoat.

2. The article of claim 1 wherein the underlying conductive CNT network layer has a sheet resistance of 25 Ω

/square or less.

3. The article of claim 1 wherein the underlying conductive CNT network layer has a sheet resistance of 1 Ω

/square or less.

4. The article of claim 1 wherein the conductive CNT network layer is p-doped.

5. The article of claim 1 wherein the conductive CNT network layer does not contain residual dispersing agent or surfactant.

6. The article of claim 1 wherein the combined conductive CNT network layer and polyurethane coating consist essentially of CNTs and polyurethane.

7. The article of claim 1 wherein the polyurethane does not contain polyether moieties.

8. The article of claim 1 wherein the polyurethane does not contain any sulfate groups.

9. The article of claim 1 wherein the polyurethane comprises an azelaic (C₉) ester moiety.

10. The article of claim 1 wherein the polyurethane the underlying conductive CNT layer maintains shielding effectiveness greater than 20 dB.

11. The article of claim 1 having a geometric surface area of at least 1 cm×

1 cm.

12. An airplane wing comprising the article of any of claims 1-11.

13. The article of any of claims 1-10 wherein the conductive CNT network layer has a thickness of 0.3 μ

m to 100 μ

m.

16. The article of any of claims 1-10 wherein the conductive CNT network layer comprises 5 weight % or less of the polymer within the CNT network layer.

14. A layered CNT-containing article, comprising:

a substrate;

a conductive carbon nanotube (CNT) network layer disposed between the substrate and a polyurethane coating having a thickness of at least 0.250 μ

m;

wherein the polyurethane coating is in direct contact with the CNT layer; and

further wherein the underlying conductive CNT network layer comprises 50 mass % or less of the coating polymer within the layer and has a sheet resistance of 120 Ω

/square or less;

wherein the conductive CNT network layer has a resistivity less than 0.05 Ω

·

cm, and wherein the CNT layer is substantially free from N-groups that are associated with the topcoat.

15. A layered CNT-containing article, comprising:

a substrate;

a conductive carbon nanotube (CNT) network layer disposed between the substrate and a polyurethane coating having a thickness of at least 0.250 μ

m;

wherein the polyurethane coating is in direct contact with the CNT layer; and

further wherein the underlying conductive CNT network layer comprises 50 mass % or less of the coating polymer within the layer and has a sheet resistance of 120 Ω

/square or less;

wherein the conductive CNT network layer comprises at least 50 mass % CNTs, and wherein the CNT layer is substantially free from N-groups that are associated with the topcoat.