Composite materials with adjustable spectral properties

Patent metadata

Field	Value
Publication number	US-11913591-B2
Application number	US-201917297888-A
Country	US
Kind code	B2
Filing date	Nov 27, 2019
Priority date	Nov 27, 2018
Publication date	Feb 27, 2024
Grant date	Feb 27, 2024

Abstract

Composite materials with adjustable spectral properties comprised of IR-reflecting micro-domains overlaying an IR-transparent elastomeric matrix, and capable of dynamically controlling IR radiation transmission are described, as well as methods of fabrication thereof. Systems with capabilities to regulate IR radiation (including heat) transmission based thereon, and methods of regulating IR radiation transmission (including thermal regulation) using the same are also provided.

First claim

The invention claimed is:

1. A composite material with adjustable spectral properties comprising:
an elastomeric matrix characterized by an elastomer thickness and comprising an IR-transparent, flexible, and stretchable material characterized by an elastic modulus;
a plurality of micro-domains overlaying the elastomeric matrix, the plurality of micro-domains being characterized by a micro-domain thickness and comprising an IR-reflecting material;
a plurality of spacings, separating the plurality of micro-domains, the plurality of spacings comprising the elastomeric matrix having no overlaid IR-reflecting material;
wherein the plurality of spacings is dynamically adjustable via mechanical manipulations of the elastomeric matrix.

2. The composite material of claim 1 , wherein the elastomer thickness is less than 300 microns.

3. The composite material of claim 1 , wherein the elastic modulus is <10 2 MPa.

4. The composite material of claim 1 , wherein the IR-transparent, flexible, and stretchable material is selected from the group consisting of: polyethylene, polyurethane, polypropylene, polycarbonate, any block co-polymer with polystyrene, such as styrene-isoprene-styrene, styrene-butylene-styrene, or styrene-ethylene-butylene-styrene block co-polymer, or any combination thereof; a metal, a metal or non-metal oxide, such as Cu, Al, TiO 2 , or SiO 2 , a ceramic, alloys thereof, or any combination thereof.

5. The composite material of claim 1 , wherein the micro-domain thickness is one of either: 2 to 100 nm or 20 nm.

6. The composite material of claim 1 , further comprising, a plurality of nanostructures anchoring the plurality of micro-domains into the elastomeric matrix, the plurality of nanostructures being characterized by a nanostructure height that is not included in the micro-domain thickness.

7. The composite material of claim 6 , wherein the plurality of micro-domains is anchored into the elastomeric matrix via a plurality of nanostructures characterized by a nanostructure height that is not included in the micro-domain thickness.

8. The composite material of claim 6 , wherein the IR-transparent, flexible, and stretchable material is functionalized with chemical groups that bind the IR-reflecting material.

9. The composite material of claim 1 , wherein the nanostructure height is one of either less than 1 micron or approximately 90 nm.

10. A method of fabricating a composite material with adjustable spectral properties comprising:
providing a support substrate;
depositing a first sub-layer of an IR-reflecting material characterized by a planar layer thickness on top of the support substrate such that the first sub-layer of the IR-reflecting material is immediately adjacent to the support substrate and comprises the IR-reflecting material deposited into a continuous featureless layer capable of reflecting IR radiation;
depositing a layer characterized by an elastomer thickness of an IR-transparent elastomeric material characterized by an elastic modulus on top of the deposited IR-reflecting material to form a composite comprising the IR-reflecting material and an IR-transparent elastomeric matrix;
adhering the IR-reflecting material and the IR-transparent elastomeric matrix;
delaminating the composite from the support substrate with application of force, such that the first sub-layer breaks into a plurality of micro-domains comprising IR-reflecting material surrounded by a plurality of spacings comprising the uncoated IR-transparent elastomeric matrix,
to produce a free standing film of the composite material with adjustable spectral properties.

11. The method of claim 10 , wherein the IR-transparent elastomeric material is cured, or otherwise heat or time-treated prior to delamination.

12. The method of claim 10 , wherein the IR-reflecting material is deposited onto the substrate support via electron-beam evaporation, or physical or chemical vapor deposition technique.

13. The method of claim 10 , wherein the support substrate is selected from the group consisting of: silicon wafer, aluminum foil, polymer, or glass.

14. The method of claim 10 , wherein the planar layer thickness is one of either 2-100 nm or 20 nm.

15. The method of claim 10 , further comprising: depositing a second sub-layer of the IR-reflecting material on top of and immediately adjacent to the first sub-layer and prior to depositing the layer of the IR-transparent elastomeric material, such that the second sub-layer comprises a plurality of nanostructures characterized by a nanostructure height, and such that depositing the layer of the IR-transparent elastomeric material buries the plurality of nanostructures into the IR-transparent elastomeric matrix, thus anchoring the first sub-layer into the IR-transparent elastomeric matrix to form the composite comprising the IR-reflecting material securely embedded into an IR-transparent elastomeric matrix.

16. The method of claim 10 , wherein the plurality of nanostructures comprises an array of nanostructures of a shape selected from the group consisting of: vertical or tilted columns, zig-zags, helices, blades, stacks of alternating thickness, or any combination thereof.

17. The method of claim 10 , wherein the nanostructure height is one of either less than 1 micron or approximately 90 nm.

18. The method of claim 10 , wherein the IR-reflecting material is selected from the group consisting of: polyethylene, polyurethane, polypropylene, polycarbonate, any block co-polymer with polystyrene, such as styrene-isoprene- styrene, styrene-butylene-styrene, or styrene-ethylene-butylene-styrene block co-polymer, or any combination thereof, a metal, a metal or non-metal oxide, such as Cu, Al, TiO 2 , SiO 2 , a ceramic, alloys thereof, or any combination thereof.

19. The method of claim 10 , wherein the IR-transparent elastomeric matrix is deposited via a method selected from the group consisting of: spin coating, spray coating, slot-casting, offset printing, blade coating, melt blowing, printing, extrusion, gravure coating, laminating, or any combination thereof.

20. The method of claim 10 , wherein the elastomer thickness is less than 300 microns.

21. The method of claim 10 , wherein the elastic modulus is <10 2 MPa.

22. A method for controlling IR radiation emitted by an object or body comprising:
enveloping the object or body emitting IR radiation in a composite material with adjustable spectral properties comprising:
an elastomeric matrix characterized by an elastomer thickness and comprising an IR-transparent, flexible, and stretchable material characterized by an elastic modulus,
a plurality of micro-domains overlaying the elastomeric matrix, the plurality of micro-domains being characterized by a micro-domain thickness and comprising an IR-reflecting material,
a plurality of spacings separating the plurality of micro-domains, the plurality of spacings comprising the elastomeric matrix having no overlaid IR-reflecting material, and
a plurality of nanostructures anchoring the plurality of micro-domains into the elastomeric matrix, the plurality of nanostructures being characterized by a nanostructure height that is not included in the micro-domain thickness,
wherein the plurality of spacings is dynamically adjustable via mechanical manipulations of the elastomeric matrix; and

mechanically manipulating the elastomeric matrix in a controlled manner to adjust the plurality of spacings between the plurality of micro-domains to release or contain IR radiati

Assignees

• Univ California

Inventors

• Gorodetsky Alon A
• Jim Steven R
• Stiubianu George
• Leung Erica
• Naughton Kyle
• Patel Priyam
• Follador Maurizio
• Karshalev Emil

Classifications

• F16L59/08 Primary

  Means for preventing radiation, e.g. with metal foil · CPC title

• B29C41/003

  characterised by the choice of material · CPC title

• B29C41/04

  Rotational or centrifugal casting, i.e. coating the inside of a mould by rotating the mould · CPC title

• C23C14/0005

  Separation of the coating from the substrate · CPC title

• C23C14/16

  on metallic substrates or on substrates of boron or silicon · CPC title