阅读说明：本技术 传导性复合材料和制造传导性复合材料的方法 (Conductive composite and method of making a conductive composite ) 是由 A·F·格罗斯 A·达斯汀 A·P·诺瓦克 关昕 A·E·索伦森 R·E·夏普 于 2021-05-06 设计创作，主要内容包括：本发明涉及传导性复合材料和制造传导性复合材料的方法。所述传导性复合材料包括第一弹性聚合物层、在第一弹性聚合物层上的导电性浆料层、以及在导电性浆料层上的第二弹性聚合物层。强化网与导电性浆料层接触。(The present invention relates to a conductive composite and a method of making a conductive composite. The conductive composite includes a first elastic polymer layer, a conductive paste layer on the first elastic polymer layer, and a second elastic polymer layer on the conductive paste layer. The reinforcing mesh is in contact with the conductive paste layer.)

1. A conductive composite, comprising:

a first elastic polymer layer;

a conductive paste layer on the first elastic polymer layer;

a second elastic polymer layer on the conductive paste layer; and

a reinforcing mesh in contact with the conductive paste layer.

2. The conductive composite of claim 1, wherein the conductive paste layer comprises a metal or alloy having a melting temperature of less than about 60 ℃, and a thickener.

3. The conductive composite of claim 2, wherein the metal or alloy comprises at least one of gallium, mercury, indium, tin, bismuth, phosphorus, lead, zinc, cadmium, antimony, and combinations thereof.

4. The conductive composite of claim 2 or 3, wherein the thickener comprises at least one of an organic thickener, an inorganic thickener, and combinations thereof.

5. The conductive composite of claim 2 or 3, wherein the thickener has an average aspect ratio in a range of 1 to 2 and an average largest dimension in a range of about 0.1 μ ι η to about 500 μ ι η.

6. The conductive composite of claim 2 or 3, wherein the thickener has an average aspect ratio in a range of about 2 to about 2000 and an average largest dimension in a range of about 0.1mm to about 10 mm.

7. The conductive composite of claim 1, wherein the electrically conductive paste layer further comprises a compatibilizer, and wherein the compatibilizer comprises at least one of an organic compatibilizer, an inorganic compatibilizer, and combinations thereof.

8. The conductive composite of claim 1, further comprising an additive for increasing thermo-oxidative stability, wherein the additive comprises at least one of a phosphate, an iron oxide, a phenolic, an antioxidant, a metal deactivator, and combinations thereof.

9. The conductive composite of claim 1, wherein the first elastic polymer layer comprises at least one of a thermoplastic polymer, a thermoset polymer, and combinations thereof.

10. The conductive composite of claim 1, wherein the second elastic polymer layer comprises at least one of a thermoplastic polymer, a thermoset polymer, and combinations thereof.

11. The conductive composite of claim 1, wherein the reinforcing mesh comprises at least one of a knitted fabric, a woven fabric, and combinations thereof.

12. The conductive composite of claim 1, wherein the reinforcing mesh comprises a conductive fabric comprising at least one of conductive filaments, a coated non-conductive fabric, and combinations thereof.

13. The conductive composite of claim 1, which is part of an aircraft.

14. The conductive composite of claim 1, being at least a portion of at least one of a wing, a fuselage, a seal, and a gasket of an aircraft.

15. A method for manufacturing a conductive composite, the method comprising:

forming a first elastic polymer layer;

forming a conductive paste layer on the first elastic polymer layer, wherein the conductive paste layer is reinforced with a reinforcing mesh; and

a second elastic polymer layer is formed on the conductive paste layer.

Technical Field

The application relates to a conductive composite material and a method for manufacturing the conductive composite material, belonging to the technical field of conductive composite materials.

Background

By broad definition, a conductive composite is any composite material having significant electrical or thermal conductivity. Such conductive composites have wide use in areas such as telecommunications, power generation and distribution, defense, aerospace, medical and other fields.

Conductive composites are typically made by combining a polymeric material with solid conductive particles and/or their properties are achieved by combining a polymeric material with solid conductive particles. To obtain sufficient conductivity, i.e. to achieve percolation, a high particle loading is generally required, typically in excess of 45 volume%. The polymers used at these particle loading levels are generally rigid materials. These particle loading levels therefore result in conductive films and coatings that have properties such as elongation at break, tensile strength, and thermal stability that make them unsuitable or difficult to use.

Accordingly, research and development continues to be performed in the field of conductive composites by those skilled in the art.

Disclosure of Invention

In one embodiment, a conductive composite includes a first elastic polymer layer, a conductive paste layer on the first elastic polymer layer, and a second elastic polymer layer on the conductive paste layer; the reinforcing mesh is in contact with the conductive paste layer.

In another embodiment, a method for making a conductive composite comprises: forming a first elastic polymer layer; forming a conductive paste layer on the first elastic polymer layer; forming a second elastic polymer layer on the conductive paste layer; the conductive paste layer is reinforced with a reinforcing mesh.

Other embodiments of the disclosed conductive composites and methods for making the conductive composites will become apparent from the following detailed description, the accompanying drawings, and the appended claims.

Drawings

Fig. 1 is a perspective view of an exemplary conductive composite of an exemplary embodiment of the present description.

Fig. 2 is a cross-sectional perspective view of the exemplary conductive composite of fig. 1 taken along lines a-a and B-B.

Fig. 3A-3C are perspective views illustrating steps for making the exemplary conductive composite of fig. 1 and 2.

FIG. 4 is a flow chart of an aircraft manufacturing and service method.

FIG. 5 is a block diagram of an aircraft.

Detailed Description

As shown in fig. 1 and 2, the conductive composite 2 includes a first elastic polymer layer 4, a conductive paste layer 6 on the first elastic polymer layer 4, and a second elastic polymer layer 8 on the conductive paste layer 6, and a reinforcing mesh 10 in contact with the conductive paste layer 6.

Elastomeric polymers are polymers that exhibit elasticity at high strain levels. In one aspect, the elastomeric polymers of the present description are polymers that exhibit an elongation at break of greater than about 50%. In another aspect, the elastic polymers of the present description are polymers that exhibit an elongation at break of greater than about 100%. In yet another aspect, the elastic polymers of the present description are polymers that exhibit an elongation at break of greater than about 200%. Elongation at break is measured as the percentage of the material strained prior to breaking when a tensile force is applied. The elongation at break is expressed as a percentage of the original length.

In one aspect, the elastomeric polymer of the present description is an electrical insulator. In one aspect, the elastomeric polymers of the present description are those having an electrical conductivity of less than about 1 x10^-8S/m electrical insulation. In another aspect, the elastomeric polymers of the present description are those having an electrical conductivity of less than about 1X 10^-9S/m electrical insulation. In yet another aspect, the elastomeric polymers of the present description are those having an electrical conductivity of less than about 1 x10^-10S/m electrical insulation.

The first and second layers of elastomeric polymer 4, 8 may comprise at least one of a thermoplastic polymer, a thermoset polymer, and combinations thereof. In one aspect, suitable elastomeric polymers for first elastomeric polymer layer 4 and second elastomeric polymer layer 8 have a viscosity of about 1000 to about 100,000cP under typical processing conditions. In another aspect, suitable elastomeric polymers for first elastomeric polymer layer 4 and second elastomeric polymer layer 8 have a viscosity of about 1000 to about 25,000cP under typical processing conditions. In yet another aspect, suitable elastomeric polymers for first elastomeric polymer layer 4 and second elastomeric polymer layer 8 have a viscosity of about 25,000 to about 50,000cP under typical processing conditions. In another aspect, suitable elastomeric polymers for first elastomeric polymer layer 4 and second elastomeric polymer layer 8 have a viscosity of about 50,000 to about 75,000cP under typical processing conditions. In another aspect, suitable elastomeric polymers for first elastomeric polymer layer 4 and second elastomeric polymer layer 8 have a viscosity of about 75,000 to about 100,000cP under typical processing conditions. In certain examples, suitable thermoplastic elastomers for use herein have a viscosity of about 1000 to about 50,000cP under typical processing conditions. As used herein, the term "typical processing conditions" includes temperatures of about room temperature (about 25 ℃) to about 400 ℃, about room temperature to about 200 ℃, or about room temperature to about 100 ℃. Measurement techniques for measuring viscosity may include viscometers, rheometers, or other suitable viscosity measuring equipment. Such thermoplastic elastomers are convenient for the manufacture of flexible materials.

Suitable elastomeric polymers for the first and second elastomeric polymer layers 4, 8 include thermoplastic elastomeric polymers, thermoset elastomeric polymers, and combinations thereof. For example, suitable elastomeric polymers for the first and second elastomeric polymer layers 4, 8 include silicone, fluorosilicone, perfluoropolyether, polybutadiene, polyester, polycarbonate, polyurethane, polyurea, polyurethane-urea, epoxy, acrylate, natural rubber, butyl rubber, polyacrylonitrile, ethylene-propylene-diene monomer (EPDM) rubber, or combinations thereof. The first elastic polymer layer 4 and the second elastic polymer layer 8 may be formed from the same or different polymer compositions.

In the context of the present specification, a slurry is any high viscosity fluid. The slurry of the present specification is not cured or hardened to a solid state. In contrast, the slurries of the present specification remain in a high viscosity fluid state. In one aspect, the slurries of the present description are materials having a viscosity in the range of about 2,000 to about 1,000,000 cP. In another aspect, the slurries of the present description are materials having a viscosity in the range of about 2,000 to about 500,000 cP. In yet another aspect, the slurries of the present description are materials having a viscosity in the range of about 2,000 to about 100,000 cP.

The conductive paste is a paste capable of carrying an electric current. In one aspect, the conductive pastes of the present description have a conductivity greater than about 1 x10¹Slurry of S/m. In another aspect, the conductive pastes of the present disclosure have a conductivity greater than about 1 x10²Slurry of S/m. In yet another aspect, the conductive pastes of the present specification have a conductivity greater than about 1 x10³Slurry of S/m. In yet another aspect, the conductive pastes of the present specification have a conductivity greater than about 1 x10⁴Slurry of S/m. In yet another aspect, the conductive pastes of the present specification have a conductivity greater than about 1 x10⁵Slurry of S/m. The conductive paste layer 6 may be uniform or heterogeneous.

In one aspect, the conductive paste comprises a metal or alloy having a melting temperature (e.g., melting point) of less than about 60 ℃. In one aspect, the metal or alloy has a melting temperature (e.g., melting point) of less than about 50 ℃. In another aspect, the metal or alloy has a melting temperature (e.g., melting point) of less than about 40 ℃. In yet another aspect, the metal or alloy has a melting temperature (e.g., melting point) of less than about 30 ℃. In yet another aspect, the metal or alloy has a melting temperature (e.g., melting point) of less than about 25 ℃. In yet another aspect, the metal or alloy has a melting temperature (e.g., melting point) of less than about 20 ℃. The conductive paste of the present specification is not limited to include a metal or an alloy. For example, the conductive paste of the present specification may include a conductive polymer instead of a metal or an alloy having a melting temperature (e.g., a melting point) of less than about 60 ℃.

The metal or alloy of the conductive paste having a melting temperature of less than about 60 ℃ may include any metal or alloy having a melting temperature of less than about 60 ℃. In one aspect, the metal or alloy includes at least one of gallium, mercury, indium, tin, bismuth, phosphorus, lead, zinc, cadmium, antimony, and combinations thereof. Suitable metals include, for example, gallium and mercury. Suitable alloys include, for example, alloys formed from gallium, mercury, indium, tin, bismuth, phosphorus, lead, zinc, cadmium, antimony, and combinations thereof. In certain examples, the alloy is an alloy comprising at least about 50 wt% gallium, bismuth, indium, mercury, or a combination thereof. In certain examples, tin, phosphorus, lead, zinc, cadmium, antimony, or combinations thereof may be included to alter the melting temperature of the alloy. In one example, the alloy used in the conductive composites disclosed herein is an alloy comprising indium and from about 50 wt% to about 97 wt% gallium. In another example, the low melting point alloy used to form the conductive composites disclosed herein is an alloy comprising about 15 wt.% to about 30 wt.% indium, about 55 wt.% to about 80 wt.% gallium, and at least one metal selected from tin and zinc. Weight percent refers to the amount by weight of the corresponding component of the metal or alloy based on the total weight of the metal or alloy. Suitable gallium alloys are commercially available from Indium corporation. Exemplary suitable alloys include Indalloy 46L, Indalloy 51, Indalloy 60, Indalloy 77, Indalloy 14, Indalloy 15, Indalloy 117, Indalloy 16, Indalloy 17, Indalloy 136, and Indalloy 19.

In one aspect, the conductive paste layer includes a thickener. When used, the thickener is typically combined with a metal or alloy having a melting temperature of less than about 60 ℃, and thus becomes a component of the conductive paste layer.

The thickener may include, for example, at least one of an organic thickener, an inorganic thickener, and combinations thereof. When the thickener comprises an organic thickener, the organic thickener can comprise, for example, at least one of maltose, carbon, and combinations thereof. When the thickener comprises an inorganic thickener, the inorganic thickener can comprise, for example, at least one of silver, copper, brass, bronze, nickel, stainless steel, carbon, coated carbon, titanium, tungsten, and combinations thereof.

In certain examples, the average aspect ratio of the thickener is in the range of 1 to about 2. The low aspect ratio thickener may take the form of, for example, a powder. The low aspect ratio thickener may have, for example, an average largest dimension in the range of about 0.1 μm to about 500 μm, such as in the range of about 50 μm to about 150 μm. In other examples, the average aspect ratio of the thickener is greater than about 2, such as in the range of about 2 to about 2000. The high aspect ratio thickener may take the form of, for example, a rod or wire. The high aspect ratio thickener may have an average largest dimension, for example, in the range of about 0.1mm to about 10 mm.

The thickener used herein functions as a viscosity modifier and may help to impede or minimize the flow of the metal or alloy within the conductive paste layer. The thickening agent used herein may be an inorganic or organic material. The thickener does not dissolve the metal or alloy, or otherwise forms a solution with the metal or alloy; they remain solid when mixed with the metal or alloy, but are wetted by the metal or alloy. Thickeners are commonly used as particles, such as rods, wire-shaped particles, substantially spherical particles, or mixtures thereof, and the particle size determines the ease with which the powder can be homogenized with the metal or alloy to form a slurry. Generally, a thickener with a higher surface area will be a better thickener than an agent with a lower surface area. The combination of thickener and metal or alloy is selected to achieve proper wetting of the thickener and rheology or modulus of the slurry. The particle size and amount are selected to produce a slurry composition having a tan delta value greater than about 1, i.e., a slurry that behaves more like a liquid than a solid, thereby making the resulting composite flexible.

The thickener may be conductive or non-conductive. The conductive thickener increases the conductivity of the resulting conductive composite 2, or can reduce the amount of conductive paste 6 needed to achieve the same conductivity.

In certain examples, the thickener comprises particles (e.g., rods or wires) of an inorganic thickener having an average aspect ratio greater than about 2 (i.e., wherein the length is at least about twice the width). The average aspect ratio can be measured using a microscope.

In other examples, the thickener includes particles (e.g., substantially spherical particles) of an inorganic thickener having an average aspect ratio of less than about 2 (i.e., wherein the length is at most about twice the width). In certain examples, the thickener comprises substantially spherical particles of an inorganic thickener having an average particle size of from about 0.1 μm to about 500 μm (from about 100nm to about 500,000 nm). Particles of this size range have a suitable surface area to act as a thickener to form a slurry with the metal or alloy. In certain examples, the thickener comprises substantially spherical particles of inorganic thickener having an average particle size of from about 1 μm to about 25 μm, or from about 25 μm to about 50 μm, or from about 50 μm to about 75 μm, or from about 75 μm to about 100 μm, or from about 100 μm to about 150 μm, or from about 150 μm to about 200 μm, or from about 200 μm to about 250 μm, or from about 250 μm to about 300 μm, or from about 300 μm to about 350 μm, or from about 350 μm to about 400 μm, or from about 450 μm to about 500 μm. In other examples, the thickener comprises substantially spherical particles of an inorganic thickener having an average particle size of about 50 μm to about 150 μm. In certain examples, the particles of the inorganic thickener have an average particle size of about 0.1 μm to about 5 μm.

In one example, the thickener is an inorganic thickener having an average aspect ratio greater than about 2 and comprises rods or wires having a length of from about 0.01mm to about 10 mm. In certain examples, the stick of inorganic thickener has a length of from about 0.01mm to about 0.5mm, or from about 0.05mm to about 10mm, or from about 0.01mm to about 0.1mm, or from about 0.1mm to about 1mm, or from about 1mm to about 5mm, or from about 5mm to about 10 mm. The use of conductive rods or wires helps the final composite to be more conductive than substantially spherical conductive particles. The overall conductivity is adjustable by adjusting the amount of metal or alloy or the amount of thickener.

In certain examples, the inorganic thickener comprises a powder having particles of a mixture of rods or wires and substantially spherical particles, or a mixture of rods, wires and substantially spherical particles.

In certain examples, the thickener comprises particles of organic thickener having an average particle size of from about 0.1 μm to about 500 μm. In certain examples, the thickener comprises particles of an organic thickener having an average particle size of from about 1 μm to about 25 μm, or from about 25 μm to about 50 μm, or from about 50 μm to about 75 μm, or from about 75 μm to about 100 μm, or from about 100 μm to about 150 μm, or from about 150 μm to about 200 μm, or from about 200 μm to about 250 μm, or from about 250 μm to about 300 μm, or from about 300 μm to about 350 μm, or from about 350 μm to about 400 μm, or from about 450 μm to about 500 μm. In other examples, the thickener includes particles of organic thickener having an average particle size of about 50 μm to about 150 μm. In certain examples, the particles of the organic thickener have an average size of about 0.1 μm to about 5 μm.

In examples where the slurry also includes a thickener, the thickener may be used in an amount to produce an appropriate viscosity and/or to adjust the conductive properties of the slurry and the resulting composite. Suitable concentrations of inorganic thickener in the slurry range from about 0.1% to about 20% by weight of the slurry composition. Suitable concentrations of organic thickener in the slurry range from about 0.1% to about 40% by weight of the slurry composition.

Suitable volume-based amounts of the thickener in the slurry composition range from about 5% to about 50% by volume of the slurry. In certain examples, the amount of thickener is from about 5% to about 10%, or from about 5% to about 15%, or from about 10% to about 20%, or from about 15% to about 25%, or from about 20% to about 30%, or from about 25% to about 35%, or from about 30% to about 45% by volume of the slurry composition. Such an amount is convenient for producing a slurry composition having a tan delta value greater than 1 (i.e., the slurry behaves more like a liquid than a solid, making the resulting composite flexible).

As described above, when the powder having the rod-or wire-shaped particles is used as the thickener, the amount of the thickener can be reduced. A suitable amount of the rod or wire thickener in the slurry is from about 2% to about 40% by volume of the slurry. In certain examples, the amount of thickener is from about 2% to about 5%, or from about 5% to about 10%, or from about 10% to about 15%, or from about 15% to about 20%, or from about 20% to about 25%, or from about 25% to about 30%, or from about 30% to about 40% by volume of the slurry composition.

Suitable conductivity can be achieved in the conductive composites disclosed herein without the need for large amounts of solid conductive particles in the slurry, i.e., a loading of such particles greater than about 45 volume percent. However, in certain instances, if insufficient metal is present in the liquid phase to form a desired level of electrical connection between the metal particles, a metal particle loading of greater than about 45 volume percent may be employed in the slurry. Thus, when desired, particle loading levels of greater than about 45 volume percent (e.g., about 45 volume percent to about 80 volume percent) can be used in the slurry.

In certain examples, the thickener used to prepare the conductive composite is an organic thickener. Suitable organic thickeners include compounds having a melting temperature above about 60 ℃ (i.e., a temperature that will prevent the thickener from melting the alloy, i.e., prior to or during manufacture of the conductive composite). Examples of such compounds are maltitol, phenol, naphthalene, 1-naphthol, 2-naphthol, 4-pyridone and carbon (including, for example, graphite and carbon black). In case the organic thickener is a compound having phenolic hydroxyl groups, the compound may react with the isocyanate groups of the di-or polyisocyanate via the hydroxyl groups, but the reaction will be slower than the urethane or urea forming reaction. When used appropriately, these compounds can be used to modify the properties of the resulting thickener. Alternatively, the organic thickener may be graphite or carbon particles.

In certain examples, the thickener is an inorganic thickener or a combination of inorganic thickeners. Suitable inorganic thickeners include metal oxides such as titanium dioxide, zinc oxide, oxides of nickel, metals or alloys having a melting temperature above about 60 ℃, or ceramic materials. The metal or alloy is selected to have a melting temperature above about 60 ℃ to prevent the thickener from melting prior to or during the manufacture of the conductive composite. Suitable metals or alloys include silver, copper, brass, bronze, nickel, stainless steel, carbon-coated, titanium, tungsten, and combinations thereof.

The thickener may be a mixture of at least one organic thickener and at least one inorganic thickener. Mixtures of organic and inorganic thickeners can be used to modify the rheology or modulus of the slurry.

In certain examples, the thickener comprises a powder having the shape of rods, wires, substantially spherical particles, or mixtures thereof, and the rods, wires, and substantially spherical particles comprise silver, copper, brass, nickel, stainless steel, aluminum, carbon, metals or alloys coated with carbon, titanium, tungsten, tin, zinc, and combinations thereof, metal oxides of nickel, ceramics, and combinations thereof, wherein the substantially spherical particles have an average particle size of about 0.1 μm to about 500 μm (from about 100nm to about 500,000nm), and the rods and wires have a length of about 0.01mm to about 10 mm.

In one aspect, the conductive paste layer includes a compatibilizer. The compatibilizer can include, for example, at least one of an organic compatibilizer, an inorganic compatibilizer, and combinations thereof. When the compatibilizer comprises an organic compatibilizer, the organic compatibilizer can comprise, for example, a surfactant, such as an ionic surfactant, a nonionic surfactant, and combinations thereof. When the compatibilizer comprises an inorganic compatibilizer, the inorganic compatibilizer can comprise, for example, a metal nanoparticle.

The compatibilizers used herein improve the processability (e.g., flowability, ease of application) of the slurry. Without wishing to be bound by theory, it is believed that mixing of the compatibilizer with the low melting point metal or alloy produces a coating of the compatibilizer on the surface of the particles or droplets of the low melting point metal or alloy, resulting in a reduction in the surface energy of the low melting point metal or alloy. Furthermore, again without wishing to be bound by theory, it is believed that the compatibilizer forms a monolayer or multiple layers on the low melting metal or alloy droplets and reduces or prevents oxidation of the metal or alloy, but it does not create a shell of the type that results from the use of an acid.

In certain examples, the compatibilizers used herein can also be used to thicken, i.e., increase the viscosity of, the slurry.

Additionally, if oxidation occurs, a compatibilizer can be added to reactivate the slurry. As used herein, "reactivation" means that the mixture of the already separated compatibilizer and low melting point metal or alloy can be returned to the form of a homogeneous slurry by adding additional compatibilizer to the separated mixture and subjecting the mixture to appropriate shear conditions as described below.

In examples where the slurry includes particles of the thickener, as discussed elsewhere herein, it is believed that the disclosed compatibilizers allow for penetration into the pores or voids formed between the particles of the thickener. The process of infiltration into the pores incorporates the liquid metal or alloy into the thickener by creating capillary pressure that holds the liquid metal or alloy between the particles.

In certain examples, the slurry used to form the conductive composite comprises a low melting point metal or alloy and a compatibilizer in a weight ratio of the low melting point metal or alloy to the compatibilizer of from about 5: 1 to about 50: 1, or from about 10: 1 to about 30: 1, or from about 15: 1 to about 25: 1, or from about 20: 1 to about 25: 1. Thus, the amount of the compatibilizing agent, expressed as a percentage of the low melting metal or alloy, is from about 2 weight percent to about 20 weight percent. Particularly useful amounts of compatibilizer are about 4 to about 10 weight percent. Weight percent refers to the amount of compatibilizer by weight based on the total weight of the slurry. Phase separation is to be avoided. At higher levels of compatibilizer, phase separation may occur, and this can be addressed using thickeners of the kind disclosed elsewhere herein.

In certain examples, the compatibilizer comprises inorganic (e.g., metal) nanoparticles having an average particle size of less than about 100nm, or less than about 90nm, or less than about 80nm, or less than about 70nm, or less than about 60nm, or less than about 50nm, or less than about 40nm, or less than about 30nm, or less than about 20 nm. The particle sizes referred to herein may be measured using, for example, a Coulter Counter or Multisizer. Suitable nanoparticles comprise a metal that is insoluble (i.e., does not dissolve) in the low melting point metal or alloy. Suitable metals for use as nanoparticles are those metals in which gallium has less than about 5 mol% solubility in the metal at room temperature. Examples of suitable metals for use as the nanoparticle compatibilizers herein include metals or alloys of silver, copper, brass, bronze, nickel, stainless steel, carbon, coated carbon, titanium, tungsten, and combinations thereof.

In certain examples, the compatibilizer is a nonionic amphiphilic compound or a mixture of nonionic amphiphilic compounds. Suitable nonionic amphiphilic compounds include fatty alcohol alkoxylates (including fatty alcohol ethoxylates), alkylphenol alkoxylates (including alkylphenol ethoxylates), fatty acid alkoxylates (including fatty acid ethoxylates), alkoxylated amines (including ethoxylated amines), fatty acid amides, polyoxyethylene-polyoxypropylene copolymers, fatty acid esters of polyhydroxy compounds, glycerol fatty acid esters, sorbitan fatty acid esters, sucrose fatty acid esters, alkyl polyglucosides, fatty amine oxides, sulfoxides, organic phosphine oxides, and mixtures thereof.

In certain examples, the compatibilizer is an ionic compound. Suitable ionic amphiphilic compounds include anionic compounds and cationic compounds. Representative anionic compounds are alkyl sulfates, alkyl ether sulfates, alkyl sulfonates, alkyl ether sulfonates, alkyl phosphates, and alkyl carboxylates. Representative cationic compounds are quaternary ammonium compounds, monoalkylammonium salts, dialkyl ammonium salts and trialkyl ammonium salts.

The selection of the particular anionic compound (or mixture thereof) or cationic compound (or mixture thereof) and the amount thereof used to form the conductive paste layer will be determined by the particular elastomeric polymer used to make the conductive composite. The type and amount of anionic or cationic compound is selected to avoid degradation or depolymerization of the elastomeric polymer.

In certain examples, the compatibilizer is a surfactant.

In certain examples, the compatibilizer is a nonionic amphiphilic compound or a mixture of such compounds. Particularly useful nonionic amphiphilic compounds are alkylphenol ethoxylates. Representative of alkylphenol ethoxylates are octylphenol ethoxylates, such as Triton^TMX-100 (polyethylene glycol p- (1,1,3, 3-tetramethylbutyl) -phenyl ether, having an average of 9.5 ethylene oxide units) and nonylphenol ethoxylate.

Other particularly useful nonionic amphiphilic compounds are poloxamers, which are triblock copolymers of poly (ethylene oxide) poly (propylene oxide) -poly (ethylene oxide) (PEO-PPO-PEO). For example, PLURONIC nonionic amphiphilic compounds are suitable.

The conductive composites of the present description may also include additional materials that impart other properties to the conductive composite. In one aspect, the conductive composite includes an additive that increases thermal oxidation stability. When the conductive composite includes an additive that increases thermal oxidation stability, the additive that increases thermal oxidation stability may include, for example, at least one of a phosphate, an iron oxide, a phenolic resin, an antioxidant, a metal deactivator, and combinations thereof. A thermo-oxidative stabilizer is a material or additive that increases the thermo-oxidative stability. A thermal oxidation stabilizer may be incorporated into the slurry composition or added to the elastic polymer layer prior to forming the conductive composite. The thermo-oxidative stabilizer may be a phosphate, an iron oxide, a phenolic antioxidant, a metal deactivator, or a combination thereof, depending on the properties desired in the conductive composite and the environment in which the conductive composite will be applied. The addition of a thermal oxidation stabilizer to the conductive composites disclosed herein will extend the operating temperature of the conductive composites. Suitable metal deactivators include nitrates such as nitric acid, citrates such as citric acid, tungstates, molybdates, chromates, and mixtures thereof.

Preparation of the slurry may be accomplished by mixing the low melting point metal or alloy, the compatibilizer, and any optional components, for example, with a centrifugal planetary mixer or a shear mixing device (capability). The resulting slurry may be stored for future use.

In certain examples, the slurry compositions disclosed herein and used to prepare conductive composites can have a loss modulus (G ") greater than a storage modulus (G'), i.e., the slurry compositions have a tan δ value greater than 1. Thus, the slurry compositions of the present disclosure behave more like a liquid than a solid. The slurry compositions of the present disclosure have a viscosity of about 500 to about 100,000cP at 1Hz, when measured using a dynamic shear rheometer according to ASTM D7175.

The thickness of each layer of the conductive composite 2 can be adjusted as needed to achieve the desired properties of the final product. In one aspect, as shown in fig. 2, the first elastic polymer layer 4 has a first thickness 14 and the second elastic polymer layer 8 has a second thickness 12. The first thickness 14 and the second thickness 12 may each be about 0.01mm to about 100 mm. In another aspect, the first thickness 14 and the second thickness 12 can each be about 0.1mm to about 10 mm. For example, the first thickness 14 and the second thickness 12 may each be about 1 mm. The first thickness 14 may be the same as or different from the second thickness 12. The conductive fiuidic layer has a third thickness 16 that may be less than or equal to at least one of the first thickness 14 and the second thickness 12. Alternatively, the third thickness 16 may be greater than at least one of the first thickness 14 and the second thickness 12. In one aspect, the third thickness 16 is less than the sum of the first thickness 14 and the second thickness 12. In another aspect, the third thickness 16 is less than at least one of the first thickness 14 and the second thickness 12. For example, the first thickness 14 and the second thickness 12 may be about 1mm, and the third thickness 16 may be less than about 1 mm. The total thickness of the conductive composite 2 may range from about 0.03mm to about 200 mm. In one aspect, the total thickness of the conductive composite 2 may be in the range of about 0.1mm to about 100 mm. In another aspect, the total thickness of the conductive composite 2 may be in a range from about 0.5mm to about 10 mm.

The conductive composite 2 may include one or more additional layers of elastic polymer and one or more additional layers of conductive paste. For example, the conductive composite may comprise a total of five layers, i.e., three elastic polymer layers alternating with two conductive paste layers.

In one aspect, the conductive composite 2 is in the form of a laminate in which a continuous layer of conductive paste 6 is sandwiched between a first elastic polymer layer 4 and a second elastic polymer layer 8. The continuous layer 6 of conductive paste may be flat or curved. In one expression, the length of the continuous conductive paste layer 6 is much greater than the thickness of the continuous conductive paste layer 6. In one aspect, the length of the continuous conductive paste layer 6 is at least 5 times the thickness of the continuous conductive paste layer 6. In another aspect, the length of the continuous conductive paste layer 6 is at least 20 times the thickness of the continuous conductive paste layer 6. In yet another aspect, the length of the continuous conductive paste layer 6 is at least 50 times the thickness of the continuous conductive paste layer 6. In another expression, the length and width of the continuous conductive paste layer 6 are much larger than the thickness of the continuous conductive paste layer 6. In one aspect, the length and width of the continuous conductive paste layer 6 is at least 5 times the thickness of the continuous conductive paste layer 6. On the other hand, the length and width of the continuous conductive paste layer 6 are at least 20 times the thickness of the continuous conductive paste layer 6. In yet another aspect, the length and width of the continuous layer of conductive paste 6 is at least 50 times the thickness of the continuous layer of conductive paste 6.

The edges of the conductive composite 2 surrounding the conductive paste layer 6 may be sealed in any manner. In one aspect, the edges of the conductive composite 2 may be sealed by the contact of the second elastic polymer layer 8 with the first elastic polymer layer 4. For example, the first and second elastic polymer layers 4, 8 may be separated by the conductive paste layer 6 except at the edges of the conductive composite 2 surrounding the conductive paste layer 6 where the first and second elastic polymer layers 4, 8 contact each other. The second elastomeric polymer layer 8 may be capable of curing to the first elastomeric polymer layer 4 to form an effective seal. The edge length 18 of the edge of the conductive composite 2 surrounding the layer of conductive paste prevents overstressing the bond between the first elastic polymer layer 4 and the second elastic polymer layer 8. In one aspect, the edge length 18 is greater than at least one of the first thickness 14 and the second thickness 12.

The conductive paste layer 6 of the present specification provides conductivity to the conductive composite 2 without requiring rigidity, and the high viscosity of the conductive paste layer suppresses leakage of the conductive paste during coating or use. As shown in fig. 2 and 3B, the present specification further includes a reinforcing mesh 10 in contact with the conductive paste layer 6. The reinforcing mesh 10 in contact with the conductive paste layer 6 alters the flow properties of the conductive paste 6 to further reduce the likelihood of leaching and better retain the conductive paste 6 within the conductive composite 2.

The reinforcing mesh 10 may be free to move relative to the first and second elastic polymer layers 4, 8 to avoid a reduction in elasticity of the conductive composite 2, or the reinforcing mesh 10 may be attached to one of the first and second elastic polymer layers 4, 8 to provide additional structural integrity.

Reinforcing mesh 10 may be conductive or non-conductive. The conductive reinforcing mesh 10 increases the conductivity of the resulting conductive composite 2, or the reinforcing mesh 10 can reduce the amount of conductive paste 6 that achieves the same conductivity. Reducing the amount of conductive paste 6 in the conductive composite 2 may further reduce the likelihood of leaching and better retain the conductive paste 6 within the conductive composite 2. In one aspect, the conductive mesh has a conductivity greater than about 1 x10³And (5) S/m. On the other hand, is electrically conductiveThe conductivity of the net is greater than about 1 x10⁴And (5) S/m. In yet another aspect, the conductive mesh has a conductivity greater than about 1 x10⁵S/m。

In one aspect, the reinforcing mesh 10 is a continuous reinforcing mesh layer in contact with the continuous conductive paste layer 6. In one expression, the length of the continuous reinforcement web layer is much greater than the thickness of the continuous reinforcement web layer. In one aspect, the length of the continuous reinforced web layer is at least 5 times the thickness of the continuous reinforced web layer. In another aspect, the length of the continuous reinforced web layer is at least 20 times the thickness of the continuous reinforced web layer. In yet another aspect, the length of the continuous reinforced web layer is at least 50 times the thickness of the continuous reinforced web layer. In another expression, the length and width of the continuous reinforcement web layer is much greater than the thickness of the continuous reinforcement web layer. In one aspect, the length and width of the continuous reinforced web layer is at least 5 times the thickness of the continuous reinforced web layer. In another aspect, the length and width of the continuous reinforced web layer is at least 20 times the thickness of the continuous reinforced web layer. In yet another aspect, the length and width of the continuous reinforced web layer is at least 50 times the thickness of the continuous reinforced web layer. The reinforcing mesh 10 may have a length and width greater than, equal to, or less than the continuous conductive paste layer 6.

Additionally, if the conductive composite 2 is in the form of a laminate, the laminate construction enables the co-location of the continuous conductive paste layer 6 and the continuous reinforcing web layer 10, with the continuous conductive paste layer 6 and the continuous reinforcing web layer 10 sandwiched between the first elastic polymer layer 4 and the second elastic polymer layer 8.

The reinforcing mesh 10 may be or include a fabric, such as a knitted fabric, a woven fabric, or a combination thereof. The fabric may be a non-conductive fabric, a conductive fabric, or a combination thereof. The conductive fabric increases the conductivity of the resulting conductive composite 2.

The nonconductive fabric may be or include, for example, a polyether-polyurea copolymer, latex, polyparaphenylene terephthalamide, aramid, nylon, polyester, or combinations thereof. However, any fabric chemically suitable for use with the conductive paste 6 may be used. The non-conductive fabric may be coated with a conductive material to create a conductive fabric.

The conductive fabric may include or be formed from conductive filaments, coated nonconductive fabrics, or combinations thereof. Exemplary conductive filaments include silver filaments, copper filaments, brass filaments, nickel filaments, stainless steel filaments, aluminum filaments, carbon filaments, coated carbon filaments, titanium filaments, tungsten filaments, tin filaments, zinc filaments, and combinations thereof. Exemplary coated nonconductive fabrics include metal-coated polyether-polyurea copolymers, metal-coated latex, metal-coated polyparaphenylene terephthalamide, metal-coated aramid, metal-coated nylon, metal-coated polyester, carbon-coated polyether-polyurea copolymers, carbon-coated latex, carbon-coated polyparaphenylene terephthalamide, carbon-coated aramid, carbon-coated nylon, carbon-coated polyester, and combinations thereof.

In certain examples, the conductive composite 2 of the present description exhibits a minimum sheet resistance of less than about 100 Ω/□. The sheet resistance of a particular conductive composite will depend on the end use. For example, when the conductive composite is used to shield electrical components from electromagnetic radiation, a minimum sheet resistance of less than about 100 Ω/□ is preferred, e.g., to minimize electromagnetic interference that may damage or harm sensitive electronics. Four-point probes can be used to determine sheet resistivity.

In certain examples, the conductive composite 2 of the present description exhibits an elongation at break of greater than or equal to about 10%. In other examples, the conductive composite 2 of the present description exhibits an elongation at break of greater than or equal to about 25%. In still other examples, the conductive composite 2 of the present description exhibits an elongation at break of greater than or equal to about 50%. Elongation at break is measured as the percentage of strain of a material before breaking when a tensile force is applied. The elongation at break is expressed as a percentage of the original length.

In certain examples, the conductive composites 2 of the present description exhibit a tensile strength of greater than or equal to about 3 MPa.

In certain examples, the conductive composite 2 of the present description has a density of less than about 7g/mL, less than about 6g/mL, less than about 5g/mL, or less than about 4 g/mL. In certain examples, the conductive composite has a density between about 2g/mL and about 10 g/mL. In other examples, the conductive composite has a density between about 10g/mL and about 20 g/mL. In other examples, the conductive composite has a density between about 1g/mL and about 5g/mL, or between about 3g/mL and about 8 g/mL. This parameter can be easily measured by determining the mass of a known volume or measuring the volume of water displaced by a known mass.

In certain examples, the conductive composite 2 of the present description exhibits about 5 x10 at 20 ℃⁵Maximum bulk conductivity of S/m.

In some examples, the conductive composite is flexible. In certain examples, the conductive composite has a tensile strength of greater than or equal to about 3 MPa. In certain examples, the conductive composite is flexible and has a tensile strength of greater than or equal to about 3 MPa.

The present disclosure also provides products, articles, and structures comprising a substrate bearing the conductive composite layers disclosed herein. Such products, articles, and structures can be made by heating a thermoplastic or thermoset conductive composite as disclosed herein and applying it to a substrate. In some examples, the conductive composite may be a portion of an aircraft, such as all or a portion of at least one of a wing and a fuselage of the aircraft. In some examples, the conductive composite may be at least one of a seal and a gasket.

As shown in fig. 3A, 3B, and 3C, the conductive composite 2 of the present disclosure may be manufactured by forming a first elastic polymer layer 4 (see fig. 3A) and forming a conductive paste layer 6 (see fig. 3B) on the first elastic polymer layer 4. Before or after the conductive paste layer 6 is formed, the conductive paste layer 6 is reinforced with a reinforcing mesh 10. Then, a second elastic polymer layer 8 is formed on the conductive paste layer 6 (see fig. 3C).

In one aspect, the step of forming the first elastomeric polymer layer includes curing the first elastomeric polymer layer. The step of curing the first elastomeric polymer layer may comprise curing the first elastomeric polymer layer.

In certain examples, the step of forming the conductive paste layer includes mixing a metal or alloy having a melting temperature of less than about 60 ℃ with a thickener. In other examples, the step of forming the conductive paste layer includes mixing a metal or alloy having a melting temperature of less than about 60 ℃ with a thickener and a compatibilizer. In other examples, the step of forming the conductive paste layer includes mixing a metal or alloy having a melting temperature of less than about 60 ℃, a thickener, and an additive to improve thermal oxidation stability, and optionally a compatibilizer. In one aspect, the step of forming the conductive paste layer includes compounding the conductive paste using shear mixing. Shear mixing may be performed at a rotational speed of about 25 to about 2000rpm, such as about 25 to about 125 rpm. In another aspect, the step of forming the conductive paste layer includes infiltrating the reinforcing mesh 10 with the conductive paste.

In certain examples, the step of forming the second elastomeric polymer layer includes curing the second elastomeric polymer layer. The step of curing the second elastic polymer layer may include bonding the second elastic polymer layer to the first elastic polymer layer.

After forming the second elastic polymer layer, the methods of the present description may include trimming the conductive composite around the conductive paste layer. In one aspect, the trimming step leaves an edge length around the conductive paste layer.

As an example, the conductive composite of the present disclosure may be made by laminating an electrically conductive paste onto a surface of a first cured or partially cured elastomeric polymer and by laminating a second elastomeric polymer thereon.

In another example, the conductive composite of the present disclosure can be manufactured by the following process: the conductive paste is spread onto a non-stick surface, uncured elastomeric polymer is applied to the paste, and the elastomeric polymer is then cured. The conductive composite can then be conveniently removed from the non-tacky surface by peeling the conductive composite from the non-tacky surface. After removal from the non-stick surface, and if necessary or desired, an additional layer of cured or uncured elastomeric polymer may be added over the conductive paste and cured as necessary to create a sandwich or laminate structure.

The laminate composite of the present disclosure may be made by laminating a conductive paste onto a surface of a first elastic polymer and applying a second elastic polymer layer on the conductive paste layer. The second elastomeric polymer may be the same or different from the first elastomeric polymer. The addition of a second elastomeric polymer layer will encapsulate the conductive paste layer.

The laminated conductive composites of the present disclosure can also be made by spreading an electrically conductive paste onto a non-stick surface, applying an uncured elastomeric polymer onto the paste, and then curing the elastomeric polymer. The conductive composite can then be conveniently removed from the non-tacky surface by peeling the conductive composite from the non-tacky surface. If desired, a second elastomeric polymer (which may be the same or different from the first elastomeric polymer) may optionally be applied over the conductive paste layer. The addition of a second elastomeric polymer layer will encapsulate the conductive paste layer.

The non-stick surface may be any suitable non-stick material. Examples of suitable non-stick materials include polytetrafluoroethylene, anodized aluminum, ceramics, and enameled cast iron.

The present disclosure also provides products, articles, and structures comprising a substrate bearing a conductive composite layer as disclosed herein, and in certain examples, flexible conductive composites as disclosed herein. Such products, articles, and structures can be made by heating a thermoplastic or thermoset conductive composite as disclosed herein and applying it to a substrate.

The conductive paste composition can be prepared by combining a low melting point metal or alloy with a compatibilizer and thoroughly mixing the resulting mixture to form a uniform paste. Mixing may be accomplished in a shear mixer at about 25 to about 2500 rpm. In certain examples, the shear mixing used to form the slurry composition is performed at about 25 to about 125rpm, or about 125 to about 250rpm, or about 250 to about 400rpm, or about 400 to about 700rpm, or about 700 to about 1500rpm, or about 1500 to about 2500 rpm. Alternatively, mixing may be performed using a centrifugal planetary mixer. The resulting slurry may be stored for future use.

In addition, the surface of the elastic polymer layer facing the conductive paste layer may be treated to improve wetting of the liquid metal. This may include ultraviolet treatment, plasma treatment or corona discharge treatment. In addition, a surfactant may be applied to the elastic polymer layer facing the conductive paste layer to improve wetting.

The following experimental examples illustrate additional features and properties of the conductive composites of the present description.

Example 1

Preparing conductive slurry: 4.93g of a non-ionic surfactant (Triton X100) was added to 49.63g of gallium alloy liquid metal and mixed for 2 minutes at 2300rpm to form a smooth and flowable slurry.

Preparation of the infiltrated reinforcement mesh: a paint brush was used to diffuse the flowable conductive paste into the silver braid.

Preparation of laminated conductive composite: NuSil R21-2615 liquid silicone rubber is a two-part, translucent silicone system with a 1:1 part A to part B mixing ratio that is thermally curable quickly. Equal portions were weighed, introduced into a Flacktek vessel, and mixed at 2300rpm for 1 minute. The resulting homogeneous resin was poured on top of the panel with Mylar release film and a 30mil thick film was cast using a glass rod. The wetted reinforcing mesh (silver braid) was placed on top of the NuSil membrane, the remaining NuSil mixture was poured on top of the reinforcing mesh and uniformly dispersed using a glass rod. A top panel (Mylar release film side down) was placed over the top of the resin and the breather sheet on top of the panel. The vacuum connector was placed inside the vacuum bag prior to sealing, a 0.5 inch slit was cut into the vacuum bag, and the vacuum hose was connected through the slit. Once the system was sealed and the pressure was maintained at-25 inches Hg, the vacuum pump was turned on. The entire vacuum bagging facility was placed on top of the 60 ℃ hot spot for a rapid thermal cure of about 40 minutes. The conductive composite was removed from the facility after 1 hour. The composite had a thickness of about 0.05 ".

Example 2

Preparing conductive slurry: 4.93g of a non-ionic surfactant (Triton X100) was added to 49.63g of gallium alloy liquid metal and mixed at 2300rpm for 2 minutes to form a smooth and flowable conductive slurry.

Preparation of the infiltrated reinforcement mesh: a paint brush is used to spread the flowable conductive slurry into the Chloroban fabric.

Preparation of laminated conductive composite: nusil R21-2615 liquid silicone rubber is a two-part, translucent silicone system with a 1:1 part A to part B mixing ratio that is thermally curable quickly. Equal portions were weighed, introduced into a Flacktek vessel, and mixed at 2300rpm for 1 minute. The resulting homogeneous resin was poured on top of the panel with Mylar release film and a 30mil thick film was cast using a glass rod. An infiltrated strengthening mesh (Chloroban) was placed on top of the NuSil film, and the remaining NuSil mixture was poured on top of the fabric and uniformly dispersed using a glass rod. A top panel (Mylar release film side down) was placed over the top of the resin and the breather sheet on top of the panel. The vacuum connector was placed inside the vacuum bag prior to sealing, a 0.5 inch slit was cut into the vacuum bag, and the vacuum hose was connected through the slit. Once the system was sealed and the pressure was maintained at-25 inches Hg, the vacuum pump was turned on. The entire vacuum bagging facility was placed on top of the 60 ℃ hot spot for rapid thermal curing for about 40 minutes. The conductive composite was removed from the facility after 1 hour. The thickness of the resulting composite was about 0.03 ".

Table 1 shows the mechanical properties of example 1 of the present description, which were tested both before and after 50 days of aging in air at 100 ℃.

TABLE 1

Table 2 shows the conductive properties of examples 1 and 2 of the present specification.

TABLE 2

Examples of the present disclosure may be described in connection with aircraft manufacturing and service method 1000 shown in FIG. 4 and aircraft 1002 shown in FIG. 5. During pre-production, aircraft manufacturing and service method 1000 may include specification and design 1004 of aircraft 1002 and material procurement 1006. During production, component/subassembly manufacturing 1008 and system integration 1010 of aircraft 1002 occurs. Thereafter, aircraft 1002 may undergo certification and delivery 1012 in order to be placed into service 1014. When used by a customer, aircraft 1002 may be scheduled for routine maintenance and service 1016, which may also include modification, reconfiguration, refurbishment, and so on.

Each of the processes of method 1000 may be performed or carried out by a system integrator, a third party, and/or an operator (e.g., a customer). For purposes of this description, a system integrator may include, but is not limited to, any number of aircraft manufacturers and major-system subcontractors; the third party may include, but is not limited to, any number of vendors, subcontractors, and suppliers; and the operator may be an airline, leasing company, military entity, maintenance organization, and so forth.

The conductive composite of the present disclosure may be employed during any one or more stages of aircraft manufacturing and service method 1000, including specification and design 1004 of aircraft 1002, material procurement 1006, component/subassembly manufacturing 1008, system integration 1010, certification and delivery 1012, commissioning 1014 of the aircraft, and daily maintenance and service 1016.

As shown in fig. 5, aircraft 1002 produced by exemplary method 1000 may include an airframe 1018 with a plurality of systems 1020 and an interior 1022. Examples of the plurality of systems 1020 may include one or more of a propulsion system 1024, an electrical system 1026, a hydraulic system 1028, and an environmental system 1030. Any number of other systems may be included. The conductive composite of the present disclosure may be used in any system of aircraft 1002.

Additionally, the present disclosure includes embodiments described in the following clauses:

1. a conductive composite (2) comprising:

a first elastic polymer layer (4);

a layer of conductive paste (6) on said first elastic polymer layer (4);

a second elastic polymer layer (8) on the conductive paste layer (6); and

a reinforcing mesh (10) in contact with the conductive paste layer (6).

2. The conductive composite (2) of clause 1, wherein the conductive paste layer (6) comprises a metal or alloy having a melting temperature of less than about 60 ℃, and a thickener.

3. The conductive composite (2) of clause 2, wherein the metal or alloy comprises at least one of gallium, mercury, indium, tin, bismuth, phosphorus, lead, zinc, cadmium, antimony, and combinations thereof.

4. The conductive composite (2) according to clause 2 or 3, wherein the thickener comprises at least one of an organic thickener, an inorganic thickener, and combinations thereof.

5. The conductive composite (2) according to any one of clauses 2-4, wherein the thickener comprises an organic thickener, wherein the organic thickener comprises at least one of maltose, carbon, and combinations thereof.

6. The conductive composite (2) according to any one of clauses 2-4, wherein the thickener comprises an inorganic thickener, wherein the inorganic thickener comprises at least one of silver, copper, brass, bronze, nickel, stainless steel, carbon, coated carbon, titanium, tungsten, and combinations thereof.

7. The conductive composite (2) according to any one of clauses 2-6, wherein the thickener has an average aspect ratio in a range from 1 to about 2.

8. The conductive composite (2) according to any one of clauses 2-7, wherein the thickener has an average aspect ratio in a range of 1 to 2 and an average largest dimension in a range of about 0.1 μ ι η to about 500 μ ι η.

9. The conductive composite (2) according to any one of clauses 2-8, wherein the thickener has an average aspect ratio in a range of 1 to about 2 and an average largest dimension in a range of about 50 μ ι η to about 150 μ ι η.

10. The conductive composite (2) of any of clauses 2-6, wherein the thickener has an average aspect ratio greater than about 2.

11. The conductive composite (2) of any of clauses 2-6, wherein the thickener has an average aspect ratio in the range of about 2 to about 2000.

12. The conductive composite (2) of any of clauses 2-6, wherein the thickener has an average aspect ratio in a range of about 2 to about 2000 and an average largest dimension in a range of about 0.1mm to about 10 mm.

13. The conductive composite (2) according to any one of clauses 1 to 12, wherein the electrically conductive paste layer (6) further comprises a compatibilizer.

14. The conductive composite (2) according to any one of clauses 1-13, wherein the electrically conductive paste layer (6) further comprises a compatibilizer, and wherein the compatibilizer comprises at least one of an organic compatibilizer, an inorganic compatibilizer, and combinations thereof.

15. The conductive composite (2) according to any one of clauses 1-14, wherein the electrically conductive paste layer (6) further comprises an organic compatibilizer, and wherein the organic compatibilizer comprises a surfactant.

16. The conductive composite (2) according to any one of clauses 1-15, wherein the electrically conductive paste layer (6) further comprises an organic compatibilizer, and wherein the organic compatibilizer comprises at least one of an ionic surfactant, a non-ionic surfactant, and a combination thereof.

17. The conductive composite (2) according to any one of clauses 1-16, further comprising an additive for increasing thermo-oxidative stability.

18. The conductive composite (2) according to any one of clauses 1-17, further comprising an additive for increasing thermo-oxidative stability, wherein the additive comprises at least one of a phosphate, an iron oxide, a phenolic, an antioxidant, a metal deactivator, and combinations thereof.

19. The conductive composite (2) according to any one of clauses 1-18, wherein the first elastic polymer layer (4) comprises at least one of a thermoplastic polymer, a thermoset polymer, and combinations thereof.

20. The conductive composite (2) according to any one of clauses 1-19, wherein the first elastic polymer layer (4) comprises at least one of silicone, fluorosilicone, perfluoropolyether, polybutadiene, polyester, polycarbonate, polyurethane, polyurea, polyurethane-urea, epoxy, acrylate, natural rubber, butyl rubber, polyacrylonitrile, ethylene-propylene-diene monomer (EPDM) rubber, and combinations thereof.

21. The conductive composite (2) according to any one of clauses 1-20, wherein the second elastic polymer layer (8) comprises at least one of a thermoplastic polymer, a thermoset polymer, and combinations thereof.

22. The conductive composite (2) according to any one of clauses 1-21, wherein the second layer of elastomeric polymer (8) comprises at least one of silicone, fluorosilicone, perfluoropolyether, polybutadiene, polyester, polycarbonate, polyurethane, polyurea, polyurethane-urea, epoxy, acrylate, natural rubber, butyl rubber, polyacrylonitrile, ethylene-propylene-diene monomer (EPDM) rubber, and combinations thereof.

23. The conductive composite (2) according to any one of clauses 1-22, wherein the first elastic polymer layer (4) has a thickness in a range from about 0.01mm to about 100 mm.

24. The conductive composite (2) according to any one of clauses 1-23, wherein the first elastic polymer layer (4) has a thickness in a range from about 0.1mm to about 10 mm.

25. The conductive composite (2) according to any one of clauses 1-24, wherein the thickness of the second elastic polymer layer (8) is in the range of about 0.01mm to about 100 mm.

26. The conductive composite (2) according to any one of clauses 1-25, wherein the thickness of the second elastic polymer layer (8) is in the range of about 0.1mm to about 10 mm.

27. The conductive composite (2) according to clause 1, wherein the thickness of the conductive paste layer is less than or equal to at least one of the thickness of the first elastic polymer layer (4) and the thickness of the second elastic polymer layer (8).

28. The conductive composite (2) according to clause 1, wherein the thickness of the conductive paste layer is greater than at least one of the thickness of the first elastic polymer layer (4) and the thickness of the second elastic polymer layer (8).

29. The conductive composite (2) according to clause 1, wherein the thickness of the conductive paste layer is greater than the sum of the thickness of the first elastic polymer layer (4) and the thickness of the second elastic polymer layer (8).

30. The conductive composite (2) according to any one of clauses 1-29, wherein the conductive paste layer (6) is uniform.

31. The conductive composite (2) according to any one of clauses 1-29, wherein the layer of electrically conductive paste (6) is non-uniform.

32. The conductive composite (2) according to any one of clauses 1-31, wherein the reinforcing mesh (10) comprises a fabric.

33. The conductive composite (2) according to any one of clauses 1-33, wherein the reinforcing mesh (10) comprises at least one of a knitted fabric, a woven fabric, and combinations thereof.

34. The conductive composite (2) of any of clauses 1-34, wherein the reinforcing mesh (10) comprises at least one of a non-conductive fabric, a conductive fabric, and combinations thereof.

35. The conductive composite (2) of any of clauses 1-34, wherein the reinforcing mesh (10) comprises a nonconductive fabric comprising at least one of a polyether-polyurea copolymer, a latex, a polyparaphenylene terephthalamide, an aramid, a nylon, a polyester, and combinations thereof.

36. The conductive composite (2) according to any one of clauses 1-34, wherein the reinforcing mesh (10) comprises a conductive fabric comprising at least one of conductive filaments, a coated non-conductive fabric, and combinations thereof.

37. The conductive composite (2) according to any one of clauses 1-34, wherein the reinforcing mesh (10) comprises a conductive fabric comprising conductive filaments, wherein the conductive filaments comprise at least one of silver filaments, copper filaments, brass filaments, nickel filaments, stainless steel filaments, aluminum filaments, carbon filaments, coated carbon filaments, titanium filaments, tungsten filaments, tin filaments, zinc filaments, and combinations thereof.

38. The conductive composite (2) of any of clauses 1-34, wherein the reinforcing mesh (10) comprises a conductive fabric comprising a coated nonconductive fabric, wherein the coated nonconductive fabric comprises at least one of a metal coated polyether-polyurea copolymer, a metal coated latex, a metal coated polyparaphenylene terephthalamide, a metal coated aramid, a metal coated nylon, a metal coated polyester, a carbon coated polyether-polyurea copolymer, a carbon coated latex, a carbon coated polyparaphenylene terephthalamide, a carbon coated aramid, a carbon coated nylon, a carbon coated polyester, and combinations thereof.

39. The conductive composite (2) according to any one of clauses 1-38, wherein the conductive composite (2) exhibits a minimum sheet resistance of less than about 100 Ω/□.

40. The conductive composite (2) of any of clauses 1-39, wherein the conductive composite (2) exhibits an elongation at break of greater than or equal to about 10%.

41. The conductive composite (2) according to any one of clauses 1-40, wherein the conductive composite (2) exhibits an elongation at break of greater than or equal to about 15%.

42. The conductive composite (2) according to any one of clauses 1-40, wherein the conductive composite (2) exhibits an elongation at break of greater than or equal to about 50%.

43. The conductive composite (2) according to any one of clauses 1-42, wherein the conductive composite (2) exhibits a tensile strength of greater than or equal to about 3 MPa.

44. The conductive composite (2) according to any one of clauses 1-43, wherein the conductive composite (2) has a density of less than about 7 g/mL.

45. The conductive composite (2) according to any one of clauses 1-44, wherein the conductive composite (2) has a density of less than about 6 g/mL.

46. The conductive composite (2) according to any one of clauses 1-45, wherein the conductive composite (2) has a density of less than about 5 g/mL.

47. The conductive composite (2) according to any one of clauses 1-46, wherein the conductive composite (2) has a density of less than about 4 g/mL.

48. The conductive composite (2) according to any one of clauses 1 to 47, wherein the conductive paste has a loss modulus (G ") greater than a storage modulus (G').

49. The conductive composite (2) of any of clauses 1-48, which is part of an aircraft.

50. The conductive composite (2) of any of clauses 1-49, which is at least a portion of at least one of a wing and a fuselage of an aircraft.

51. The conductive composite (2) of any of clauses 1-49, which is at least one of a seal and a gasket.

52. A method for manufacturing a conductive composite, the method comprising:

forming a first elastic polymer layer;

forming a conductive paste layer on the first elastic polymer layer, wherein the conductive paste layer is reinforced with a reinforcing mesh; and

a second elastic polymer layer is formed on the conductive paste layer.

53. The method of clause 52, wherein the step of forming the first elastomeric polymer layer comprises curing the first elastomeric polymer layer.

54. The method of clauses 52 or 53, wherein the step of forming the conductive paste layer comprises mixing a metal or alloy having a melting temperature of less than about 60 ℃ with a thickening agent.

55. The method of any of clauses 52-54, wherein the step of forming the conductive paste layer comprises mixing a metal or alloy having a melting temperature of less than about 60 ℃, a thickener, and a compatibilizer.

56. The method of any of clauses 52-55, wherein the step of forming the conductive paste layer comprises mixing a metal or alloy having a melting temperature of less than about 60 ℃, a thickener, and an additive for increasing thermal oxidation stability.

57. The method according to any one of clauses 52-56, wherein the step of forming the conductive paste layer comprises compounding the conductive paste using shear mixing.

58. The method according to any one of clauses 52-57, wherein the step of forming the conductive paste layer comprises compounding the conductive paste using shear mixing, wherein the shear mixing is performed at a rotational speed of about 25rpm to about 2000 rpm.

59. The method according to any of clauses 52-58, wherein the step of forming the conductive paste layer comprises compounding the conductive paste using shear mixing, wherein the shear mixing is performed at a rotational speed of about 25-125 rpm.

60. The method according to any one of clauses 52-59, wherein the step of forming the conductive paste layer comprises infiltrating the reinforcing mesh (10) with the conductive paste layer.

61. The method of any of clauses 52-60, wherein the step of forming the second elastomeric polymer layer comprises curing the second elastomeric polymer layer.

62. The method of clause 61, wherein the step of curing the second elastic polymer layer comprises bonding the second elastic polymer layer to the first elastic polymer layer.

63. The method of any of clauses 52-62, wherein the first and second elastic polymer layers encapsulate the conductive paste layer.

64. The method of any of clauses 52-63, further comprising trimming the conductive composite around the conductive paste layer.

65. The method of any of clauses 52-64, wherein trimming the conductive composite around the layer of conductive paste leaves an edge length around the layer of conductive paste.

66. The method of any of clauses 65-66, wherein the edge length is greater than or equal to at least one of the thickness of the first elastic polymer layer and the thickness of the second elastic polymer layer.

While various embodiments of the disclosed conductive composites and methods for making conductive composites have been shown and described, modifications may occur to those skilled in the art upon reading the specification. This application includes such modifications and is limited only by the scope of the claims.