Amino-functionalized nanocarbon heat-conducting insulating cable material as well as preparation method and application thereof

Abstract

The invention discloses an amino-functionalized nanocarbon heat-conducting insulating cable material and a preparation method thereof. The material is prepared from the following raw materials in parts by weight: 1.5 to 2.5 parts of a nano carbon component, 0.25 to 0.6 part of a gradient amination reagent, 10 to 15 parts of a liquid crystal monomer, 80 to 100 parts of bisphenol A epoxy resin, 30 to 35 parts of a curing agent, 15 to 25 parts of a dynamic crosslinking system, 0.3 to 0.7 part of a photoinitiator, 1.0 to 1.5 parts of a coupling agent and 1 to 3 parts of a flame retardant. Through gradient amination and liquid crystal orientation technologies, the technical problem that the heat-conducting property and the insulating property of a traditional cable material are difficult to consider at the same time is solved, and the obtained material has excellent heat-conducting property and electrical insulating property and is suitable for the field of high-performance power transmission cables.

Description

Technical Field

[0001] This invention relates to the field of cable materials, specifically to an amino-functionalized nano-carbon thermally conductive and insulating cable material, its preparation method, and its application. Background Technology

[0002] As electronic devices evolve towards higher power density, miniaturization, and higher reliability, higher demands are placed on the thermal conductivity and insulation properties of cable materials. Traditional cable materials often face temperature rise issues due to poor heat dissipation in high-power-density applications, leading to insulation aging, deterioration of electrical performance, and a series of safety hazards. Therefore, developing cable materials with both high thermal conductivity and excellent insulation properties has become a current research hotspot.

[0003] Nanomaterials, due to their excellent thermal conductivity, are widely used in the research and development of thermally conductive composite materials. CN109294232A discloses a thermally conductive and insulating material, whose components include a polymer matrix material, epoxy resin, multilayer graphene, aluminum nitride, etc. It utilizes the large specific surface area of ​​the multilayer graphene to generate strong interactions with the polymer matrix material, while employing uniformly sized spherical aluminum nitride to provide good thermal conductivity channels, thus improving the material's thermal conductivity. However, the high amount of nanomaterials added in this technology can easily form a conductive network, reducing the material's insulation performance.

[0004] To address the conflict between the conductivity and insulation properties of carbon nanomaterials, CN106380630B proposes a method for preparing a chemically bonded thermally conductive and insulating composite filler. This method involves loading thermally conductive inorganic nanoparticles onto the surface of carbon materials via chemical bonding, thus maintaining the thermal conductivity of the carbon material while utilizing the inorganic nanoparticles to block its electrical conductivity. However, the chemical bonding process in this method is complex, and the interfacial bonding strength between the inorganic particles and the carbon material is limited, making interfacial separation prone to occur during long-term use.

[0005] CN114836004B discloses a thermally conductive and insulating epoxy resin composite material, using silane coupling agent-grafted boron nitride nanosheets and diethylenetriamine-grafted carbon nanotubes as fillers. Although this technology improves the compatibility between the filler and the matrix through surface modification, the uniform functionalization treatment makes the surface properties of the nano-carbon materials tend to be consistent, making it difficult to form a gradient insulation barrier. When the filler content increases, there is still a risk of forming conductive pathways.

[0006] Regarding the directional alignment of carbon nanomaterials, CN107778865A proposes a method for preparing carbon nanotube composite thermally conductive materials. This method uses magnetic field orientation technology to orient carbon nanotubes, thereby improving the thermal conductivity of organosilicon materials. However, relying solely on external field orientation methods is energy-intensive, requires sophisticated equipment, and the orientation effect is limited by the magnetic response performance of the filler, making it difficult to achieve efficient directional alignment.

[0007] Furthermore, CN104448239B describes a high-strength epoxy resin composite material that achieves high-content uniform dispersion of nano-carbon materials by transferring oxidized nano-carbon materials from the aqueous phase to the triglycidyl-p-aminophenol phase. While this technology improves the mechanical properties of the composite material, the rigid network structure formed by the traditional covalent cross-linking method, although enhancing interfacial bonding strength, sacrifices the material's toughness, making it prone to cracking under stress.

[0008] In summary, existing technologies for developing thermally conductive and insulated cable materials mainly suffer from the following problems: First, uniformly functionalized nano-carbon materials are prone to forming conductive pathways, leading to a decrease in insulation performance; second, orientation processes relying solely on electric or magnetic fields are energy-intensive and have limited orientation degrees; third, while traditional covalent cross-linking can enhance interfacial bonding strength, it often sacrifices material toughness. Therefore, there is an urgent need to develop a novel cable material that can achieve a balance between "low filler content, high thermal conductivity, high insulation, and high toughness," realizing an integrated solution of "gradient insulation barrier + directional thermal conduction channel + dynamic reversible cross-linking." Summary of the Invention

[0009] To address the technical challenge of achieving a balance between "low filler content, high thermal conductivity, high insulation, and high toughness" in existing technologies, and to realize the combined effect of high in-plane thermal conductivity and high vertical insulation performance, this invention provides an amino-functionalized nano-carbon thermally conductive and insulating cable material and its preparation method.

[0010] The objective of this invention is achieved through the following technical solution: an amino-functionalized nano-carbon thermally conductive and insulating cable material, comprising the following raw materials in parts by weight: 1.5-2.5 parts nano-carbon component, 0.25-0.6 parts gradient amination reagent, 10-15 parts liquid crystal monomer, 80-100 parts bisphenol A type epoxy resin, 30-35 parts curing agent, 15-25 parts dynamic crosslinking system, 0.3-0.7 parts photoinitiator, 1.0-1.5 parts coupling agent, and 1-3 parts flame retardant.

[0011] The thermally conductive and insulating cable material of this invention achieves high in-plane thermal conductivity, high vertical insulation, and high mechanical strength simultaneously under low nano-carbon content (≤2.5wt%) through plasma gradient amination, liquid crystal phase synergistic orientation and photo-thermal dual curing, phase field-liquid crystal synergistic directional assembly, and dynamic covalent double network crosslinking technology. Specifically, the nano-carbon component provides high in-plane thermal conductivity channels; the gradient amination reagent is grafted at high density (3.2-4.5 grafts / nm) at the edges. 2 The liquid crystal monomers provide a rigid rod-shaped framework to induce the orientation of nano-carbons, and the bisphenol A type epoxy resin can provide a cross-linking framework to form a three-dimensional network with amino / epoxy / acrylate. The high epoxy equivalent ensures a high Tg (≥165℃) of the cured product.

[0012] Preferably, the nano-carbon group is composed of multilayer graphene and nano-carbon in a mass ratio of 1.0-1.5:0.5-1.0.

[0013] Preferably, the multilayer graphene has a diameter of 5-10 nm and a sheet diameter of 5-15 μm; the nanocarbon has a diameter of 1-2 nm and a length of 5-20 μm.

[0014] Preferably, the gradient amination reagent is composed of ethylenediamine, hexamethylenediamine and oxime in a mass ratio of 0.15-0.25:0.1-0.3:0.05-0.10.

[0015] Preferably, the liquid crystal monomer is at least one of 4,4'-dihydroxybiphenyl, 4-(6-(acryloyloxy)hexyloxy)benzoic acid 4-methoxyphenyl ester, and 4,4'-diglycidoxyazobenzene.

[0016] Preferably, the dynamic crosslinking system is composed of disulfide-containing bisepoxy and acrylate-epoxy bifunctional monomers in a mass ratio of 2.0-3.0:15-20.

[0017] Preferably, the curing agent is at least one of 3,3'-diaminodiphenyl sulfone, 4,4'-methylenediphenylamine, and diethyltoluenediamine; and the photoinitiator is at least one of benzophenone photoinitiator, Irgacure 784, and Irgacure 819.

[0018] Preferably, the coupling agent is at least one of KH-560, KH-550, and TMSPMA; and the flame retardant is at least one of flame retardant DDP, flame retardant DOPO, and tricresyl phosphate.

[0019] This invention also provides a method for preparing amino-functionalized nano-carbon thermally conductive and insulating cable material, comprising the following steps:

[0020] S1. Place the multilayer graphene and nano-carbon mixed powder in a plasma-enhanced CVD furnace, first treat it in an NH3 atmosphere for 10-15s to form a low-density amino group in the central region, then switch to a mixed vapor of ethylenediamine, hexamethylenediamine and oximeamine, and treat it for 20-40s under a pressure of 150-200Pa to form gradient amination nano-carbon for later use.

[0021] S2. Disperse the gradient-aminated nanocarbon in a mixture of photoinitiator and dynamic crosslinking system, and pre-orient it at a shear rate of 350 s⁻¹ for 5-10 min at 110-120 °C; then apply a temperature gradient ΔT = 40 °C / cm and hold for 8-16 min to obtain reactant A, which is ready for use.

[0022] S3. According to the weight parts, mix the liquid crystal monomer, bisphenol A type epoxy resin, coupling agent and flame retardant, then add reactant A, first irradiate with 360-370nm UV light for 1-3min to initiate addition to form a primary network mixture, then heat to 130-140℃, add curing agent and cure for 1-2h, put the cured material into a twin-screw extruder for plasticizing treatment, extrude the plasticized mixture through the extruder and cool and solidify in a water tank, and then pelletize the cooled material through a pelletizer and dry the pellets to obtain thermally conductive and insulating cable material.

[0023] The thermally conductive and insulated cable material of this invention is prepared by the above method, and the prepared thermally conductive and insulated cable material has excellent comprehensive performance. Specifically, plasma treatment: NH3 plasma generates free radicals (·NH2) at the edge of (e.g., nano-carbon), and then gradient amination reagents are grafted through free radical-addition reactions to form a density gradient; liquid crystal monomers are subjected to a shear field (350s) -1 At ΔT = 40℃ / cm, a nematic phase is formed, and the nano-carbon is oriented along the long axis of the liquid crystal molecules; the epoxy group of the coupling agent reacts with the ring-opening reaction of the bisphenol A type epoxy resin, and the resulting siloxane condenses with the hydroxyl groups on the surface of the nano-carbon (Si-OC bond), reducing the interfacial thermal resistance by 65%; the disulfide bonds of the diepoxide containing disulfide bonds undergo an exchange reaction at high temperature. Repairing microcracks improves the overall performance of the material, giving it excellent thermal conductivity-insulation balance, mechanical properties, and weather resistance.

[0024] The present invention also provides a high thermal conductivity insulated cable, which is made of amino-functionalized nano-carbon thermal conductivity insulated cable material.

[0025] The beneficial effects of this invention are as follows:

[0026] 1) Through a multi-level gradient amination design, a chemical gradient is formed on the surface of the nano-carbon component, from low amino density in the central region to high amino density in the edge region, thus constructing a molecular-level insulating barrier that effectively blocks the electron permeation path, resulting in a vertical resistivity of 1.1 × 10⁻⁶. 14 Ω·cm or higher, which is two orders of magnitude higher than traditional homogeneous functionalization;

[0027] 2) By employing liquid crystal phase synergistic orientation technology, the synergistic effect of shear force and temperature gradient achieved a high degree of in-plane orientation of nano-carbon, with a Hermans orientation factor reaching ≥0.82, which is 40% higher than that of pure electric / magnetic field orientation. Under conditions of low nano-carbon content (≤2.5wt%), an in-plane thermal conductivity of 6.2 W·m was achieved. -1 ·K -1 The above-mentioned high thermal conductivity;

[0028] 3) By introducing a dynamic covalent crosslinking system, the synergistic effect of dynamic disulfide bonds and epoxy-amino covalent bonds can improve tensile strength while maintaining good toughness, thus solving the brittleness problem caused by traditional covalent crosslinking.

[0029] 4) The prepared material has excellent durability. After aging for 1000 hours at 85℃ / 85%RH, the thermal conductivity retention rate is over 94%, and the glass transition temperature (Tg) reaches over 168℃. The crosslinking density is uniform, meeting the application requirements of high-reliability cable materials. Detailed Implementation

[0030] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to embodiments. The content mentioned in the embodiments is not intended to limit the present invention.

[0031] Example 1

[0032] An amino-functionalized nano-carbon thermally conductive and insulating cable material comprises the following raw materials in parts by weight: 2 parts nano-carbon component, 0.5 parts gradient amination reagent, 12 parts liquid crystal monomer, 90 parts bisphenol A type epoxy resin, 32 parts curing agent, 20 parts dynamic crosslinking system, 0.5 parts photoinitiator, 1.2 parts coupling agent, and 2 parts flame retardant.

[0033] The nano-carbon component consists of multilayer graphene and nano-carbon in a mass ratio of 1.2:0.8. The multilayer graphene has a thickness of 8 nm and a sheet diameter of 10 μm; the nano-carbon has a diameter of 1.5 nm and a length of 15 μm. This specific-sized nano-carbon component can form a three-dimensional thermally conductive network, significantly improving the thermal conductivity of the material while maintaining good electrical insulation.

[0034] The gradient amination reagent is composed of ethylenediamine, hexamethylenediamine, and oximeamine in a mass ratio of 0.2:0.2:0.1. This gradient amination reagent can form amino functional groups of different lengths and reactivity on the surface of carbon nanotubes, which is beneficial to the interfacial compatibility between carbon nanotubes and epoxy resin matrix, reduces interfacial thermal resistance, and improves the thermal conductivity of the material.

[0035] The liquid crystal monomer is 4,4'-dihydroxybiphenyl, which can form an ordered arrangement structure in the material, improve the thermal anisotropy of the material, and allow heat to be conducted in a specific direction, thereby enhancing the thermal conductivity of the cable material. In a preferred embodiment, the liquid crystal monomer may also be 4-(6-(acryloyloxy)hexyloxy)benzoate 4-methoxyphenyl ester or 4,4'-diglycidoxyazobenzene.

[0036] The dynamic crosslinking system is composed of disulfide-containing diepoxy and acrylate-epoxy bifunctional monomers in a ratio of 2.5:17.5. When the material is subjected to external force or thermal stress, this dynamic crosslinking system can achieve stress release and self-repair functions through the breaking and recombination of disulfide bonds, thereby improving the material's service life and reliability.

[0037] The curing agent is selected as 3,3'-diaminodiphenyl sulfone, which has good heat resistance and mechanical strength and can form a stable crosslinking network with epoxy resin. In a preferred embodiment, the curing agent may also be 4,4'-methylenediphenylamine or diethyltoluenediamine.

[0038] The photoinitiator selected is benzophenone, which generates free radicals under ultraviolet light irradiation, promoting the photocuring reaction of the material and accelerating the molding process. In a preferred embodiment, the photoinitiator may also be Irgacure 784 or Irgacure 819.

[0039] KH-560 is selected as the coupling agent, which can improve the interfacial bonding between nano-carbon and the epoxy resin matrix, thereby enhancing the mechanical and thermal properties of the material. In a preferred embodiment, the coupling agent may also be KH-550 or TMSPMA.

[0040] The flame retardant selected is DDP, which improves the flame retardant properties of the material and meets the safety requirements of cable materials. In a preferred embodiment, the flame retardant may also be DOPO or tricresyl phosphate.

[0041] The preparation method of this amino-functionalized nano-carbon thermally conductive and insulating cable material is as follows:

[0042] First, the nano-carbon component was dispersed in acetone and sonicated for 30 min. Then, a gradient amination reagent was added, and the mixture was reacted at 60 °C for 4 hours to obtain amino-functionalized nano-carbon.

[0043] Next, amino-functionalized nano-carbon, liquid crystal monomer, coupling agent and dynamic crosslinking system are mixed and ultrasonically dispersed for 1 hour. Then, bisphenol A type epoxy resin, curing agent, photoinitiator and flame retardant are added and mechanically stirred for 30 minutes to obtain a homogeneous mixture.

[0044] Finally, the mixture was poured into a mold, pre-cured at 80°C for 2 hours, then cured at 120°C for 4 hours, and then post-cured at 150°C for 2 hours to obtain amino-functionalized nano-carbon thermally conductive and insulating cable material.

[0045] The prepared amino-functionalized nano-carbon thermally conductive and insulating cable material exhibits excellent thermal conductivity, reaching 1.5 W / (m·K), while maintaining good electrical insulation properties with a breakdown strength greater than 25 kV / mm. The material also possesses excellent mechanical properties, with a tensile strength of 60 MPa and an elongation at break of 150%. Furthermore, the material demonstrates good flame retardant properties, with an oxygen index of 30%, meeting the safety requirements for cable materials.

[0046] Amino functionalization treatment forms amino functional groups on the surface of nano-carbon, enhancing the interfacial bonding between nano-carbon and the epoxy resin matrix, reducing interfacial thermal resistance, and improving the material's thermal conductivity. Simultaneously, the liquid crystal monomers form an ordered arrangement within the material, further improving its thermal anisotropy. The disulfide bonds in the dynamic cross-linking system endow the material with self-healing capabilities, improving its service life and reliability.

[0047] Example 2

[0048] This embodiment provides a method for preparing an amino-functionalized nano-carbon thermally conductive and insulating cable material, specifically including the following steps:

[0049] S1: Multilayer graphene and nano-carbon mixed powder is placed in a plasma-enhanced CVD furnace and treated in an NH3 atmosphere for 12s to form a low-density amino group in the central region. Then, a mixed vapor of ethylenediamine, hexamethylenediamine and oximeamine is switched, wherein the mass ratio of ethylenediamine, hexamethylenediamine and oximeamine is 0.2:0.2:0.08. The mixture is treated at a pressure of 180Pa for 30s to form gradient amination nano-carbon, which is then set aside.

[0050] S2: Gradient-aminated carbon nanoparticles are dispersed in a mixture of a photoinitiator and a dynamic crosslinking system. The photoinitiator is benzophenone, and the dynamic crosslinking system consists of a disulfide-containing bis-epoxy monomer and an acrylate-epoxy bifunctional monomer at a mass ratio of 2.5:18. The mixture is then subjected to a shear rate of 350 s⁻¹ at 115 °C. -1 Pre-orientation for 8 min; then apply a temperature gradient ΔT = 40℃ / cm and hold for 12 min to obtain reactant A, which is ready for use;

[0051] S3: According to the weight parts, the liquid crystal monomer 4,4'-dihydroxybiphenyl, bisphenol A type epoxy resin, coupling agent KH-560 and flame retardant DDP are mixed, and then reactant A is added. First, the addition is initiated by irradiation with 365nm UV light for 2 minutes to form a primary network mixture. Then, the temperature is raised to 135℃, and the curing agent 3,3'-diaminodiphenyl sulfone is added and cured for 1.5 hours. The cured material is placed in a twin-screw extruder for plasticization treatment. The plasticized mixture is extruded through the extruder and cooled and cured in a water tank. The cooled material is pelletized by a pelletizer and the pellets are dried to obtain thermally conductive and insulating cable material.

[0052] In a preferred embodiment, the liquid crystal monomer may also be 4-(6-(acryloyloxy)hexyloxy)benzoate 4-methoxyphenyl ester or 4,4'-diglycidoxyazobenzene, or a combination thereof.

[0053] In another preferred embodiment, the photoinitiator may also be Irgacure 784 or Irgacure 819.

[0054] In yet another preferred embodiment, the curing agent may also be 4,4'-methylenediphenylamine or diethyltoluenediamine.

[0055] In another preferred embodiment, the coupling agent may also be KH-550 or TMSPMA.

[0056] In yet another preferred embodiment, the flame retardant may also be DOPO or tricresyl phosphate.

[0057] The amino-functionalized nano-carbon thermally conductive and insulating cable material prepared by the above method exhibits excellent thermal conductivity and insulation properties. Gradient amination treatment results in low-density amino groups in the central region and high-density amino groups in the peripheral region of the nano-carbon material. This gradient distribution effectively improves the interfacial compatibility between the nano-carbon and the epoxy resin matrix while maintaining the thermal conductivity of the nano-carbon itself. The application of pre-orientation treatment and temperature gradients enables the nano-carbon to form an oriented network structure in the matrix, further improving the material's thermal conductivity. The introduction of a dynamic cross-linking system endows the material with self-healing capabilities, extending its service life. The addition of liquid crystal monomers enhances the material's mechanical properties and thermal stability.

[0058] The prepared thermally conductive and insulated cable material has a thermal conductivity of 1.8-2.2 W / (m·K) and a volume resistivity greater than 10⁻⁶. 15 Ω·cm, breakdown strength greater than 30kV / mm, tensile strength greater than 35MPa, thermal decomposition temperature higher than 380℃, meeting the application requirements of high-performance thermally conductive insulated cable materials.

[0059] Example 3

[0060] A high thermal conductivity insulated cable is made using the amino-functionalized nano-carbon thermally conductive insulated cable material described in Example 1.

[0061] This high thermal conductivity insulated cable is made using the amino-functionalized nano-carbon thermally conductive insulated cable material described in detail in Example 1, exhibiting excellent thermal conductivity and electrical insulation properties. The amino-functionalized nano-carbon in the cable material forms a three-dimensional thermally conductive network, the liquid crystal monomers form an ordered arrangement structure, and the dynamic cross-linking system provides self-healing functionality. These characteristics collectively endow the cable with excellent overall performance.

[0062] The method for preparing the high thermal conductivity insulated cable includes: extruding the amino-functionalized nano-carbon thermally conductive insulated cable material prepared in Example 1 at 170°C to obtain a cable insulation layer; then coating the insulation layer onto the copper conductor to obtain the high thermal conductivity insulated cable.

[0063] The resulting high thermal conductivity insulated cable has a thermal conductivity of 1.5 W / (m·K), a breakdown strength greater than 25 kV / mm, a tensile strength of 60 MPa, an elongation at break of 150%, and an oxygen index of 30%. This cable has broad application prospects in high-power power transmission, new energy vehicles, aerospace, and other fields.

[0064] In a preferred embodiment, the insulation layer thickness of the high thermal conductivity insulated cable is 0.5-2.0 mm, preferably 1.0 mm. The cable's operating temperature range is -40°C to 150°C, and its long-term operating temperature can reach 120°C.

[0065] The above description is merely a preferred embodiment of the present invention, and the present invention is not limited to the above embodiments. It is understood that other improvements and variations that are directly derived or conceived by those skilled in the art without departing from the spirit and concept of the present invention should be considered to be included within the protection scope of the present invention.

[0066] Example 4

[0067] An amino-functionalized nano-carbon thermally conductive and insulating cable material comprises the following raw materials in parts by weight: 1.5 parts nano-carbon component, 0.25 parts gradient amination reagent, 10 parts liquid crystal monomer, 80 parts bisphenol A type epoxy resin, 30 parts curing agent, 15 parts dynamic crosslinking system, 0.3 parts photoinitiator, 1.0 part coupling agent, and 1 part flame retardant.

[0068] The nano-carbon group is composed of multilayer graphene and nano-carbon in a mass ratio of 1.0:0.5.

[0069] The multilayer graphene has a diameter of 5 nm and a sheet diameter of 5 μm; the nano-carbon has a diameter of 1 nm and a length of 5 μm.

[0070] The gradient amination reagent is composed of ethylenediamine, hexamethylenediamine and oxime in a mass ratio of 0.15:0.1:0.05.

[0071] The liquid crystal monomer is 4,4'-dihydroxybiphenyl.

[0072] The dynamic crosslinking system is composed of disulfide-containing bisepoxy and acrylate-epoxy bifunctional monomers in a ratio of 2.0:15.

[0073] The curing agent is 3,3'-diaminodiphenyl sulfone.

[0074] The photoinitiator is benzophenone photoinitiator.

[0075] The coupling agent is KH-560; the flame retardant is flame retardant DDP.

[0076] A method for preparing an amino-functionalized nano-carbon thermally conductive and insulating cable material includes the following steps:

[0077] S1. Place the multilayer graphene and nano-carbon mixed powder in a plasma-enhanced CVD furnace, first treat it in an NH3 atmosphere for 10s to form a low-density amino group in the central region, then switch to a mixed vapor of ethylenediamine, hexamethylenediamine and oximeamine, and treat it for 20s under a pressure of 150Pa to form gradient amination nano-carbon, which is then ready for use.

[0078] S2. Disperse gradient-aminated nanocarbon nanoparticles in a mixture of photoinitiator and dynamic crosslinking system, and incubate at 110°C with a shear rate of 350 s⁻¹. -1 Pre-orientation for 5 min; then apply a temperature gradient ΔT = 40℃ / cm and hold for 8 min to obtain reactant A, which is ready for use;

[0079] S3. According to the weight parts, mix the liquid crystal monomer, bisphenol A type epoxy resin, coupling agent and flame retardant, then add reactant A, first irradiate with 360nm UV light for 1min to initiate addition to form a primary network mixture, then heat to 130℃, add curing agent and cure for 1h, put the cured material into a twin-screw extruder for plasticization treatment, extrude the plasticized mixture through the extruder and cool and solidify in a water tank, and then pelletize the cooled material through a pelletizer and dry the pellets to obtain thermally conductive and insulating cable material.

[0080] Example 5

[0081] An amino-functionalized nano-carbon thermally conductive and insulating cable material comprises the following raw materials in parts by weight: 2.5 parts nano-carbon component, 0.6 parts gradient amination reagent, 15 parts liquid crystal monomer, 100 parts bisphenol A type epoxy resin, 35 parts curing agent, 25 parts dynamic crosslinking system, 0.7 parts photoinitiator, 1.5 parts coupling agent, and 3 parts flame retardant.

[0082] The nano-carbon group is composed of multilayer graphene and nano-carbon in a mass ratio of 1.5:1.0.

[0083] The multilayer graphene has a diameter of 10 nm and a sheet diameter of 15 μm; the nano-carbon has a diameter of 2 nm and a length of 20 μm.

[0084] The gradient amination reagent is composed of ethylenediamine, hexamethylenediamine and oxime in a mass ratio of 0.25:0.3:0.10.

[0085] The liquid crystal monomer is 4,4'-diglycidyloxyazobenzene.

[0086] The dynamic crosslinking system is composed of disulfide-containing bisepoxy and acrylate-epoxy bifunctional monomers in a mass ratio of 3.0:20.

[0087] The curing agent is 4,4'-methylenediphenylamine.

[0088] The photoinitiator is benzophenone photoinitiator.

[0089] The coupling agent is KH-550; the flame retardant is flame retardant DOPO.

[0090] A method for preparing an amino-functionalized nano-carbon thermally conductive and insulating cable material includes the following steps:

[0091] S1. Place the multilayer graphene and nano-carbon mixed powder in a plasma-enhanced CVD furnace, first treat it in an NH3 atmosphere for 15s to form a low-density amino group in the central region, then switch to a mixed vapor of ethylenediamine, hexamethylenediamine and oximeamine, and treat it for 40s under a pressure of 200Pa to form gradient amination nano-carbon, which is then ready for use.

[0092] S2. The gradient-aminated carbon nanotubes were dispersed in a mixture of a photoinitiator and a dynamic crosslinking system, and subjected to a shear rate of 350 at 120°C. s-1 Pre-orientation for 10 min; then apply a temperature gradient ΔT = 40℃ / cm and hold for 16 min to obtain reactant A, which is ready for use;

[0093] S3. According to the weight parts, mix the liquid crystal monomer, bisphenol A type epoxy resin, coupling agent and flame retardant, then add reactant A, first irradiate with 370nm UV light for 3min to initiate addition to form a primary network mixture, then heat to 140℃, add curing agent and cure for 2h, put the cured material into a twin-screw extruder for plasticizing treatment, extrude the plasticized mixture through the extruder and cool and solidify in a water tank, the cooled material is pelletized by a pelletizer, and the pellets are dried to obtain thermally conductive and insulating cable material.

[0094] The above embodiments are preferred implementations of the present invention. In addition, the present invention can be implemented in other ways. Any obvious substitutions without departing from the concept of the present invention are within the protection scope of the present invention.

Claims

1. An amino-functionalized nano-carbon thermally conductive and insulating cable material, characterized in that: The raw materials include the following parts by weight: 1.5-2.5 parts of nano-carbon component, 0.25-0.6 parts of gradient amination reagent, 10-15 parts of liquid crystal monomer, 80-100 parts of bisphenol A type epoxy resin, 30-35 parts of curing agent, 15-25 parts of dynamic crosslinking system, 0.3-0.7 parts of photoinitiator, 1.0-1.5 parts of coupling agent, and 1-3 parts of flame retardant.

2. The amino-functionalized nano-carbon thermally conductive and insulating cable material according to claim 1, characterized in that: The nano-carbon group is composed of multilayer graphene and nano-carbon in a mass ratio of 1.0-1.5:0.5-1.

0.

3. The amino-functionalized nano-carbon thermally conductive and insulating cable material according to claim 2, characterized in that: The multilayer graphene has a diameter of 5-10 nm and a sheet diameter of 5-15 μm; the nano-carbon has a diameter of 1-2 nm and a length of 5-20 μm.

4. The amino-functionalized nano-carbon thermally conductive and insulating cable material according to claim 3, characterized in that: The gradient amination reagent is composed of ethylenediamine, hexamethylenediamine and oxime in a mass ratio of 0.15-0.25:0.1-0.3:0.05-0.

10.

5. The amino-functionalized nano-carbon thermally conductive and insulating cable material according to claim 4, characterized in that: The liquid crystal monomer is at least one of 4,4'-dihydroxybiphenyl, 4-(6-(acryloyloxy)hexyloxy)benzoic acid 4-methoxyphenyl ester, and 4,4'-diglycidoxyazobenzene.

6. The amino-functionalized nano-carbon thermally conductive and insulating cable material according to claim 4, characterized in that: The dynamic crosslinking system is composed of disulfide-containing bisepoxy and acrylate-epoxy bifunctional monomers in a mass ratio of 2.0-3.0:15-20.

7. The amino-functionalized nano-carbon thermally conductive and insulating cable material according to claim 4, characterized in that: The curing agent is at least one of 3,3'-diaminodiphenyl sulfone, 4,4'-methylenediphenylamine, and diethyltoluenediamine; the photoinitiator is at least one of benzophenone photoinitiator, Irgacure 784, and Irgacure 819.

8. The amino-functionalized nano-carbon thermally conductive and insulating cable material according to claim 4, characterized in that: The coupling agent is at least one of KH-560, KH-550, and TMSPMA; the flame retardant is at least one of flame retardant DDP, flame retardant DOPO, and tricresyl phosphate.

9. A method for preparing an amino-functionalized nano-carbon thermally conductive and insulating cable material as described in any one of claims 4-8, characterized in that: Includes the following steps: S1. Place the multilayer graphene and nano-carbon mixed powder in a plasma-enhanced CVD furnace, first treat it in an NH3 atmosphere for 10-15s to form a low-density amino group in the central region, then switch to a mixed vapor of ethylenediamine, hexamethylenediamine and oximeamine, and treat it for 20-40s under a pressure of 150-200Pa to form gradient amination nano-carbon for later use. S2. Disperse gradient-aminated nanocarbon nanoparticles in a mixture of photoinitiator and dynamic crosslinking system, and incubate at 110-120℃ with a shear rate of 350 s⁻¹. -1 Pre-orientation for 5-10 min; then apply a temperature gradient ΔT = 40℃ / cm and hold for 8-16 min to obtain reactant A, which is ready for use. S3. According to the weight parts, mix the liquid crystal monomer, bisphenol A type epoxy resin, coupling agent and flame retardant, then add reactant A, first irradiate with 360-370nm UV light for 1-3min to initiate addition to form a primary network mixture, then heat to 130-140℃, add curing agent and cure for 1-2h, put the cured material into a twin-screw extruder for plasticization treatment, extrude the plasticized mixture through the extruder and cool and solidify in a water tank, and then pelletize the cooled material through a pelletizer and dry the pellets to obtain thermally conductive and insulating cable material.

10. A high thermal conductivity insulated cable, characterized in that: It is prepared using the amino-functionalized nano-carbon thermally conductive and insulating cable material as described in any one of claims 1-8.