阅读说明：本技术 一种织物增强的导热填料-可溶聚合物导热复合材料及其制备方法 (Fabric-reinforced heat-conducting filler-soluble polymer heat-conducting composite material and preparation method thereof ) 是由 王大明 丛冰 王春博 赵君禹 周宏伟 赵晓刚 陈春海 于 2020-07-20 设计创作，主要内容包括：本发明提供了一种织物增强的导热填料-可溶聚合物导热复合材料及其制备方法,属于导热复合材料技术领域。本发明利用可溶聚合物使导热填料有序分散在复合材料中,使得导热填料在可溶聚合物中富集形成导热网络,为声子传输提供媒介,搭建起有效的传热路径,降低界面热阻,提高了导热系数；本发明利用织物作为力学增强网络,能够大幅度提升复合材料的机械性能,扩大其应用领域。本发明制备的织物增强的导热填料-可溶聚合物导热复合材料的导热系数可达1.42W/mK,拉伸强度可达41MPa,拉伸模量可达2.5GPa,断裂伸长率可达6.1％。(The invention provides a fabric-reinforced heat-conducting filler-soluble polymer heat-conducting composite material and a preparation method thereof, belonging to the technical field of heat-conducting composite materials. The soluble polymer is utilized to enable the heat-conducting filler to be orderly dispersed in the composite material, so that the heat-conducting filler is enriched in the soluble polymer to form a heat-conducting network, a medium is provided for phonon transmission, an effective heat-conducting path is built, the interface thermal resistance is reduced, and the heat-conducting coefficient is improved; the invention utilizes the fabric as a mechanical reinforcing network, can greatly improve the mechanical property of the composite material and expand the application field thereof. The fabric-reinforced heat-conducting filler-soluble polymer heat-conducting composite material prepared by the invention has the heat conductivity coefficient of 1.42W/mK, the tensile strength of 41MPa, the tensile modulus of 2.5GPa and the elongation at break of 6.1%.)

1. A preparation method of a fabric-reinforced heat-conducting filler-soluble polymer heat-conducting composite material comprises the following steps:

mixing the heat-conducting filler, the dispersing agent and the soluble polymer to obtain a dispersion liquid;

coating the dispersion liquid on a fabric, and carrying out phase transition on the obtained fabric in a solidification liquid to obtain a compound;

and carrying out hot pressing on the compound to obtain the fabric-reinforced heat-conducting filler-soluble polymer heat-conducting composite material.

2. The production method according to claim 1, wherein the heat conductive filler comprises any one of silicon carbide, aluminum nitride, boron nitride, aluminum oxide, and silicon dioxide.

3. The method of claim 1, wherein the soluble polymer comprises any one of polysulfone, polyethersulfone, polyphenylenesulfone, phenolphthalein type polyaryletherketone, bisphenol A type polyaryletherketone, polyetherimide, polyphenylene sulfide, polyamide, polybutylene terephthalate, polyphenylene oxide, polycarbonate, and polyoxymethylene.

4. The method according to claim 1, wherein the dispersant comprises any one of N, N-dimethylacetamide, N-methylpyrrolidone, N-dimethylformamide, dimethyl sulfoxide, dioxane, dichloromethane, chloroform, tetrahydrofuran, and acetone.

5. The method according to any one of claims 2 to 4, wherein the mass ratio of the heat conductive filler to the soluble polymer is (40-60) to (40-60); the mass ratio of the sum of the mass of the heat-conducting filler and the mass of the soluble polymer to the mass of the dispersing agent is (15-20) to (80-85).

6. The production method according to claim 1, wherein the fabric includes any one of a glass fiber fabric, a carbon fiber fabric, a polyetheretherketone fiber fabric, a kevlar fiber fabric, and a polyimide fabric; the mass ratio of the dispersion liquid to the fabric is (9-11): 0.85.

7. The method of claim 6, wherein the fabric form of the glass fiber fabric, the carbon fiber fabric, the polyetheretherketone fiber fabric and the Kevlar fiber fabric includes any one of a three-dimensional fiber fabric, a needle punched fiber fabric, a unidirectional tape and a non-woven fabric.

8. The preparation method according to claim 1, wherein the coagulating liquid is one or more of water, methanol, ethanol and isopropanol; the phase transition temperature is room temperature, and the time is 24-48 h.

9. The method according to claim 1, wherein the hot pressing is performed at a pressure of 1.5 to 2.0MPa and a temperature of 250 to 300 ℃.

10. The fabric-reinforced heat-conducting filler-soluble polymer heat-conducting composite material prepared by the preparation method of any one of claims 1 to 9 comprises a fabric matrix and a heat-conducting filler-soluble polymer dispersed in the fabric matrix, wherein the fabric matrix is used as a mechanical reinforcing network, the heat-conducting filler-soluble polymer is used as a heat-conducting network, and the mechanical reinforcing network and the heat-conducting network are mutually penetrated.

Technical Field

The invention relates to the technical field of heat-conducting composite materials, in particular to a fabric-reinforced heat-conducting filler-soluble polymer heat-conducting composite material and a preparation method thereof.

Background

In recent years, electronic information technology has been rapidly developed, and in particular, the microelectronics industry is moving toward high density and high speed. Electronic devices and equipment are continuously developing in the direction of high power, thinning, multi-functionalization, high performance and miniaturization. When electronic devices in an integrated circuit operate efficiently at high frequencies and high speeds, a large amount of heat is inevitably generated. These heat can pose significant challenges to the performance, efficiency and lifetime of electronic devices. Therefore, in order to meet the increasing heat dissipation requirements of the electronic information industry, it is necessary to improve the thermal conductivity of the existing polymers.

In order to improve the heat-conducting property of the polymer, the main method used by most domestic and foreign research institutions and related enterprises at present is to uniformly dope inorganic heat-conducting fillers such as carbon nanotubes, graphene, aluminum oxide, boron nitride and the like in resin to prepare the high-heat-conducting composite material. However, the thermal conductivity of the existing polymer is low, when the amount of the filler is small, the filler is uniformly dispersed in the matrix, the thermal conductive fillers are isolated from each other, a phonon transmission medium is lacked, heat transmission is not facilitated, and an effective thermal conductive path cannot be formed, so that a large amount of thermal conductive filler (the amount of the filler is more than 20%) is often added to obtain ideal thermal conductivity. However, when the amount of the filler is large (> 20%), the heat-conducting filler can form an effective heat-conducting path in the matrix to improve the heat-conducting property, but the mechanical property of the composite material is greatly reduced, so that the application of the composite material is limited.

Disclosure of Invention

The invention aims to provide a fabric-reinforced heat-conducting filler-soluble polymer heat-conducting composite material and a preparation method thereof.

In order to achieve the above object, the present invention provides the following technical solutions:

the invention provides a preparation method of a fabric-reinforced heat-conducting filler-soluble polymer heat-conducting composite material, which comprises the following steps:

mixing the heat-conducting filler, the dispersing agent and the soluble polymer to obtain a dispersion liquid;

coating the dispersion liquid on a fabric, and carrying out phase transition on the obtained fabric in a solidification liquid to obtain a compound;

and carrying out hot pressing on the compound to obtain the fabric-reinforced heat-conducting filler-soluble polymer heat-conducting composite material.

Preferably, the thermally conductive filler includes any one of silicon carbide, aluminum nitride, boron nitride, aluminum oxide, and silicon dioxide.

Preferably, the soluble polymer includes any one of polysulfone, polyethersulfone, polyphenylenesulfone, phenolphthalein type polyaryletherketone, bisphenol a type polyaryletherketone, polyetherimide, polyphenylene sulfide, polyamide, polybutylene terephthalate, polyphenylene oxide, polycarbonate, and polyoxymethylene.

Preferably, the dispersant includes any one of N, N-dimethylacetamide, N-methylpyrrolidone, N-dimethylformamide, dimethylsulfoxide, dioxane, dichloromethane, chloroform, tetrahydrofuran, and acetone.

Preferably, the mass ratio of the heat-conducting filler to the soluble polymer is (40-60): 40-60; the mass ratio of the sum of the mass of the heat-conducting filler and the mass of the soluble polymer to the mass of the dispersing agent is (15-20) to (80-85).

Preferably, the fabric comprises any one of a glass fiber fabric, a carbon fiber fabric, a polyether-ether-ketone fiber fabric, a Kevlar fiber fabric and a polyimide fabric; the mass ratio of the dispersion liquid to the fabric is (9-11): 0.85.

Preferably, the fabric form of the glass fiber fabric, the carbon fiber fabric, the polyetheretherketone fiber fabric and the kevlar fiber fabric includes any one of a three-dimensional fiber woven fabric, a needle-punched fiber woven fabric, a unidirectional tape and a non-woven fabric.

Preferably, the coagulating liquid is one or more of water, methanol, ethanol and isopropanol; the phase transition temperature is room temperature, and the time is 24-48 h.

Preferably, the hot pressing pressure is 1.5-2.0 MPa, and the temperature is 250-300 ℃.

The invention provides a fabric-reinforced heat-conducting filler-soluble polymer heat-conducting composite material prepared by the preparation method in the technical scheme, which comprises a fabric substrate and a heat-conducting filler-soluble polymer dispersed in the fabric substrate, wherein the fabric substrate is used as a mechanical reinforcing network, the heat-conducting filler-soluble polymer is used as a heat-conducting network, and the mechanical reinforcing network and the heat-conducting network are mutually penetrated.

The invention provides a preparation method of a fabric-reinforced heat-conducting filler-soluble polymer heat-conducting composite material, which comprises the following steps: mixing the heat-conducting filler, the dispersing agent and the soluble polymer to obtain a dispersion liquid; coating the dispersion liquid on a fabric, and carrying out phase transition on the obtained fabric in a solidification liquid to obtain a compound; and carrying out hot pressing on the compound to obtain the fabric-reinforced heat-conducting filler-soluble polymer heat-conducting composite material. The invention utilizes the good dispersibility of the soluble polymer to lead the heat-conducting filler to be orderly dispersed in the composite material, leads the heat-conducting filler to be enriched in the soluble polymer to form a heat-conducting network, provides a medium for phonon transmission, builds an effective heat-conducting path, reduces the interface thermal resistance and improves the heat-conducting coefficient; the invention utilizes the fabric as a mechanical reinforcing network, can greatly improve the mechanical property of the composite material and expand the application field thereof.

The preparation process of the invention is simple and convenient, has low requirements on process equipment, and develops another way for the practical application of materials.

In the fabric-reinforced heat-conducting filler-soluble polymer heat-conducting composite material prepared by the invention, the fabric substrate is used as a mechanical reinforcing network, the heat-conducting filler-soluble polymer is used as a heat-conducting network, and the mechanical reinforcing network and the heat-conducting network penetrate through the fabric to form the composite material. The results of the examples show that the thermal conductivity coefficient of the fabric-reinforced heat-conducting filler-soluble polymer heat-conducting composite material prepared by the invention can reach 1.42W/mK, the tensile strength can reach 41MPa, the tensile modulus can reach 2.5GPa, and the elongation at break can reach 6.1%.

Detailed Description

The invention provides a preparation method of a fabric-reinforced heat-conducting filler-soluble polymer heat-conducting composite material, which comprises the following steps:

mixing the heat-conducting filler, the dispersing agent and the soluble polymer to obtain a dispersion liquid;

coating the dispersion liquid on a fabric, and carrying out phase transition on the obtained fabric in a solidification liquid to obtain a compound;

and carrying out hot pressing on the compound to obtain the fabric-reinforced heat-conducting filler-soluble polymer heat-conducting composite material.

In the present invention, unless otherwise specified, all the starting materials required for the preparation are commercially available products well known to those skilled in the art.

The invention mixes the heat conductive filler, the dispersant and the soluble polymer to obtain the dispersion liquid. In the present invention, the thermally conductive filler preferably includes any one of silicon carbide, aluminum nitride, boron nitride, aluminum oxide, and silicon dioxide, and more preferably boron nitride or silicon carbide. In the invention, the particle size of the heat-conducting filler is preferably 1-2 μm.

In the present invention, the soluble polymer preferably includes any one of Polysulfone (PSF), Polyethersulfone (PES), polyphenylenesulfone (PPSU), phenolphthalein type polyaryletherketone (PEK-C), bisphenol a type polyaryletherketone (PEK-M), Polyetherimide (PEI), polyphenylene sulfide (PPS), Polyamide (PA), polybutylene terephthalate (PBT), polyphenylene oxide (PPO), Polycarbonate (PC) and Polyoxymethylene (POM), and more preferably polysulfone or polyethersulfone. The molecular weight of the soluble polymer is not particularly limited in the present invention, and commercially available soluble polymers well known in the art may be used. In the examples of the present invention, the commercially available commercial sources and types of the soluble polymer are specifically: polysulfone (PSF), shanghai mclin biochemical, trade mark: p875323; polyethersulfone (PES), basf, germany, designation E7020P; polyphenylene Sulfone (PPSU), Suwei, USA, trade name R-5100; phenolphthalein type polyaryletherketone (PEK-C, manufactured by Shandong Haoran specialty plastics Co., Ltd.) with a viscosity of 0.6 dL/g; bisphenol A type polyaryletherketone (PEK-M), manufactured by Shandong Haoran specialty GmbH, with viscosity of 0.6 dL/g; polyetherimide (PEI), manufactured by technical engineering plastics Co., Ltd, Dongguan, trade name 2300; polyphenylene Sulfide (PPS), american chevrolet philips chemical co., inc, brand QC 200N; polyamide (PA), japan, mark number UBESTA3035 LUI; polybutylene terephthalate (PBT), shanghai san qi plastication science and technology limited, brand 4830; polyphenylene Oxide (PPO), nantong star synthetic materials ltd, designation LXR 045; polycarbonate (PC), bayer, germany, designation 2805; polyoxymethylene (POM), Nippon Baochi, designation NW-02C.

The invention utilizes the good dispersibility of the soluble polymer in the dispersant to ensure that the heat-conducting filler is uniformly distributed and reduce aggregation.

In the present invention, the dispersant preferably includes any one of N, N-dimethylacetamide, N-methylpyrrolidone, N-dimethylformamide, dimethylsulfoxide, dioxane, dichloromethane, chloroform, tetrahydrofuran, and acetone, and more preferably N, N-dimethylacetamide, N-methylpyrrolidone, dimethylsulfoxide, or dioxane.

In the invention, the mass ratio of the heat-conducting filler to the soluble polymer is preferably (40-60): 40-60), and more preferably (45-55): 45-55; the mass ratio of the sum of the mass of the heat-conducting filler and the mass of the soluble polymer to the mass of the dispersing agent is preferably (15-20): 80-85, and more preferably 20: 80.

In the invention, the process of mixing the heat-conducting filler, the dispersing agent and the soluble polymer is preferably to mix the heat-conducting filler and the dispersing agent firstly, perform ultrasonic dispersion on the obtained mixture, then add the soluble polymer, and perform magnetic stirring at room temperature for 6-8 hours to obtain a uniformly dispersed dispersion liquid. In the invention, the ultrasonic dispersion is preferably carried out in an ultrasonic cleaning machine, the power of the ultrasonic dispersion is preferably 250-400W, more preferably 300-350W, and the time is preferably 0.5-2 h, more preferably 1.0-1.5 h. The stirring process is not particularly limited in the present invention, and a uniform dispersion can be obtained according to a process well known in the art. The invention firstly disperses the heat-conducting filler in the dispersant after ultrasonic treatment, then adds the soluble polymer to dissolve the soluble polymer in the dispersant, promotes the heat-conducting filler to disperse in the soluble polymer in the stirring process, and most of the heat-conducting filler is wrapped by the polymer to form a dispersion liquid with uniformly dispersed heat-conducting filler-soluble polymer (the heat-conducting filler and the soluble polymer have no interaction and belong to physical mixing), namely the dispersibility of the heat-conducting filler is increased by the soluble polymer.

After the dispersion liquid is obtained, the invention coats the dispersion liquid on the fabric, and the obtained fabric is subjected to phase transition in the solidification liquid to obtain the compound. In the invention, the fabric preferably comprises any one of a glass fiber fabric, a carbon fiber fabric, a polyether-ether-ketone fiber fabric, a Kevlar fiber fabric and a polyimide fabric; the fabric form of the glass fiber fabric, the carbon fiber fabric, the polyether-ether-ketone fiber fabric and the Kevlar fiber fabric preferably comprises any one of a three-dimensional fiber braided fabric, a needle-punched fiber braided fabric, a unidirectional tape and a non-woven fabric; the Kevlar fabric is preferably a needle punched Kevlar fabric; the carbon fiber fabric is preferably a carbon fiber non-woven fabric, and the polyetheretherketone fiber fabric is preferably a three-dimensional polyetheretherketone fiber fabric. The specific source of the fabric is not particularly limited in the present invention, and commercially available products well known in the art may be used; in the embodiment of the present invention, the sources and types of the fabric are specifically: glass fiber fabric, Changzhou city Hongsha new material science and technology GmbH, brand E-DBLT1000M 50-10; carbon fiber fabric, Changzhou city Hongsha new material science and technology limited company, brand C-LPTN 600-12; polyether Ether ketone (PEEK) fiber fabric, Changchun Jida engineering research Co., Ltd, with a density of 200g/m²(ii) a Kevlar fabric, Hayngett glass fiber cloth, Inc., having a density of 200g/m²(ii) a Polyimide fabric, Shandong Aori costume, Inc., with a density of 200g/m². The invention utilizes the fabric to provide a mechanical enhancement function, enhances the mechanical property of the heat-conducting composite material and expands the application field of the heat-conducting composite material.

In the present invention, the mass ratio of the dispersion to the fabric is preferably (9 to 11):0.85, and more preferably (9.5 to 10.5): 0.85. In the present invention, the coating method is preferably a dripping method, and the process of the dripping method is not particularly limited, and the dispersion may be uniformly impregnated into the fabric. In the coating process, the soluble polymer can play a role of an adhesive, the heat-conducting filler and the fabric are bonded together, and the uniform dispersion of the heat-conducting filler on the fabric is promoted.

After the coating is completed, the present invention preferably immerses the resultant fabric in a coagulating liquid to perform phase transition. In the invention, the coagulating liquid is preferably one or more of water, methanol, ethanol and isopropanol, and is more preferably water; the water is preferably deionized water; when the solidification liquid is a plurality of the above, the invention has no special limitation on the proportion of different kinds of solidification liquid, and the proportion can be any. The solidification solution is a non-solvent of soluble polymers, and can convert the soluble polymers in the dispersion solution on the fabric from a liquid state to a solid state.

In the invention, the temperature of the phase transition is preferably room temperature, and the time is preferably 24-48 h, more preferably 30-45 h, and further preferably 36-40 h. In the phase transition process, the heat-conducting filler-soluble polymer which is uniformly immersed in the dispersion liquid in the fabric is converted into a solid-phase continuous high-molecular three-dimensional network from a liquid phase due to insolubility in a solidification liquid, and the solid-phase continuous high-molecular three-dimensional network is used as a heat-conducting network in a composite material system, so that the composite material is endowed with good heat-conducting performance.

After the phase transformation is completed, the obtained fabric is preferably dried, and the drying process preferably comprises the steps of drying for 8-12 hours in a common oven at 130 ℃, and then drying for 3-5 hours in a vacuum oven at 180-220 ℃ to obtain the composite. The conventional oven of the present invention is a conventional oven well known in the art, and the present invention does not specifically limit the conventional oven and the vacuum oven, and any equipment well known in the art may be used. The invention removes the dispersant in the coagulating liquid and the residual dispersing liquid by drying.

In the invention, the compound takes the fabric as a matrix, and the solid heat conduction filler-soluble polymer is uniformly dispersed in the fabric matrix.

After the compound is obtained, the compound is hot-pressed to obtain the fabric reinforced heat-conducting filler-soluble polymer heat-conducting composite material. In the invention, the hot pressing pressure is preferably 1.5-2.0 MPa, more preferably 1.6-1.8 MPa, and the temperature is preferably 250-300 ℃, more preferably 260-280 ℃. The hot pressing equipment is not particularly limited, and the parameter conditions can be met. The invention eliminates the pores between the heat-conducting filler-soluble polymer and the fabric through hot pressing, and further enhances the heat-conducting property of the composite material.

The invention provides a fabric-reinforced heat-conducting filler-soluble polymer heat-conducting composite material prepared by the preparation method in the technical scheme, which comprises a fabric substrate and a heat-conducting filler-soluble polymer dispersed in the fabric substrate, wherein the fabric substrate is used as a mechanical reinforcing network, the heat-conducting filler-soluble polymer is used as a heat-conducting network, and the mechanical reinforcing network and the heat-conducting network are mutually penetrated. In the fabric-reinforced heat-conducting filler-soluble polymer heat-conducting composite material, the mass ratio of the heat-conducting filler, the soluble polymer and the fabric is preferably (0.54-1.32): (0.54-1.32): 0.85, more preferably (0.6 to 1.0): (0.6-1.0): 0.85.

the technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the following examples, the particle size of the thermal conductive filler used is 1 to 2 μm.