Polymer foaming material with high conductive path and preparation method of polymer foaming material

Abstract

The invention provides a polymer foaming material with a high conductive path and a preparation method of the polymer foaming material, and belongs to the field of polymer foaming materials, a polymer matrix material, a compatilizer and a conductive filler are internally mixed and blended to obtain a blend, and the conductive filler is a mixture of silver nanowires and MXene; carrying out hot pressing treatment on the blend to obtain a foamed sheet; and carrying out foaming treatment on the foamed sheet, so that the conductive filler forms a continuous three-dimensional conductive path on the surface of a foam hole wall, and the polymer foamed material with the high conductive path is obtained. The silver nanowires and MXene form a continuous three-dimensional conductive network on the surface of the cell wall, so that the conductivity of the material is remarkably improved; a low-density polymer foaming material is prepared through a supercritical foaming process, and the lightweight requirement is met; the uniform distribution of the conductive medium and the addition of the compatilizer avoid the damage of the foam structure, and the material has high tensile strength, and can be widely applied to the fields of electromagnetic shielding, antistatic packaging, flexible electronic equipment, sensors and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer foam materials, and in particular to a polymer foam material with a high conductive path and a preparation method thereof. Background Art

[0002] Polypropylene (PP) is a general-purpose plastic widely used in industries such as industry, packaging, automobiles, and electronics. It is highly favored for its excellent mechanical properties, chemical stability, and low cost. However, polypropylene itself is an insulating material with poor electrical conductivity, which limits its application in electronics, electromagnetic shielding, sensors, and other fields. In order to give polypropylene conductive properties, researchers have constructed a conductive network by adding conductive fillers such as carbon nanotubes, graphene, metal particles, or conductive polymers. However, traditional filler addition methods often face problems such as uneven filler dispersion, discontinuous conductive paths, and decreased mechanical properties of the material.

[0003] In recent years, silver nanowires (AgNWs) and MXene, two new types of conductive nanomaterials, have shown great application potential in the field of composite materials due to their high conductivity, excellent mechanical properties, and good dispersibility. Silver nanowires have a high aspect ratio and excellent conductivity, and can form a continuous conductive network at low addition levels. MXene is a two-dimensional material obtained by exfoliation of transition metal carbides or nitrides. It has extremely high conductivity and surface functionality and can form a good interface with the polymer matrix. However, how to effectively introduce these two conductive fillers into the polymer matrix and construct a stable highly conductive pathway through a reasonable processing technology remains a major challenge in current research.

[0004] In view of this, it is necessary to design an improved polymer foam material with high conductive path and a preparation method thereof to solve the above problems. Summary of the Invention

[0005] In view of the technical problems existing in the background technology, the present application provides a polymer foam material with a high conductive path and a preparation method thereof, aiming to solve the technical problems that the existing conductive fillers are unevenly distributed in the foaming system, resulting in unstable conductive performance, and the addition of conductive fillers destroys the foam structure, affecting its mechanical properties and lightweight characteristics.

[0006] In a first aspect, the present application provides a method for preparing a polymer foam material with a high conductive path, comprising the following steps:

[0007] S1. The polymer matrix material, the compatibilizer and the conductive filler are mixed by mixing to obtain a blend, wherein the conductive filler is a mixture of silver nanowires and MXene;

[0008] S2. The blend is subjected to hot pressing to obtain a foamed sheet;

[0009] S3. The foamed sheet is subjected to a foaming treatment so that the conductive filler forms a continuous three-dimensional conductive path on the surface of the cell wall, thereby obtaining a polymer foam material with a high conductive path.

[0010] As a further improvement of the present application, in step S1, the polymer matrix material is one or more of polypropylene, polyethylene, polystyrene, and polylactic acid.

[0011] As a further improvement of the present application, the added amount of the MXene is 3 to 8% of the mass of the polymer matrix material, and the mass ratio of the MXene to the silver nanowires is 1:(1.5 to 2).

[0012] As a further improvement of the present application, the compatibilizer is maleic anhydride grafted polypropylene, and the added amount is 8 to 12% of the mass of the polymer matrix material.

[0013] As a further improvement of the present application, the temperature of the banburying blending is 160-180° C., and the banburying time is 10-20 min.

[0014] As a further improvement of the present application, in step S2, the temperature of the hot pressing treatment is 170-180°C, the pressure is 4-6 MPa, and the thickness of the foamed sheet is 0.5-2.0 mm.

[0015] As a further improvement of the present application, in step S3, the temperature of the foaming treatment is 170-180°C, the pressure is 8-12 MPa, and the pressure holding time is 1-3 hours.

[0016] As a further improvement of the present application, the pressure relief rate of the foaming treatment is 5 to 20 MPa / s.

[0017] As a further improvement of the present application, the foaming agent for the foaming treatment is one or more of supercritical carbon dioxide, nitrogen, butane, and fluorocarbon compounds.

[0018] In a second aspect, the present application provides a polymer foam material with a high conductive path, which is prepared by the preparation method described in the first aspect.

[0019] The beneficial effects of this application are:

[0020] The present application provides a polymer foam material with a high conductive path and a preparation method thereof, wherein a polymer matrix material, a compatibilizer and a conductive filler are mixed by mixing to obtain a blend, wherein the conductive filler is a mixture of silver nanowires and MXene; the blend is subjected to a hot pressing treatment to obtain a foamed sheet; the foamed sheet is foamed so that the conductive filler forms a continuous three-dimensional conductive path on the surface of the pore wall, thereby obtaining a polymer foam material with a high conductive path. The present application forms a continuous three-dimensional conductive network on the surface of the pore wall by silver nanowires and MXene, significantly improving the conductive properties of the material; a low-density polymer foam material is prepared by a supercritical foaming process to meet lightweight requirements; the uniform distribution of the conductive medium and the addition of the compatibilizer avoid the destruction of the pore structure, and the material has a high tensile strength. The material can be widely used in electromagnetic shielding, antistatic packaging, flexible electronic devices, sensors and other fields.

[0021] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] To more clearly illustrate the technical solution of this application, the following is a brief introduction to the drawings used in this application. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be derived from these drawings without inventive effort.

[0023] Figure 1 This is a schematic diagram of the conductive network of the polymer foam material in the embodiment of the present application;

[0024] Figure 2 This is an electron microscope image of the conductive network of the pore wall of the cross-section of the polymer foam material in the embodiment of the present application;

[0025] Figure 3 This is a comparison chart of the electrical conductivity of the polymer foam material in Example 1 of the present application and Comparative Example 1. DETAILED DESCRIPTION

[0026] The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned figure descriptions are intended to cover non-exclusive inclusions.

[0028] In the description of the embodiments of this application, the technical terms "first" and "second" are used only to distinguish different objects and should not be understood to indicate or imply relative importance or implicitly specify the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise clearly and specifically defined.

[0029] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0030] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0031] Traditional polymer foams are non-conductive and cannot meet the demands of electronic devices, electromagnetic shielding, and other fields. Existing conductive fillers (such as carbon black and carbon nanotubes) are unevenly distributed within the foaming system, resulting in unstable conductivity. The addition of conductive fillers can disrupt the foam's cellular structure, affecting its mechanical properties and lightweight characteristics.

[0032] In order to solve the technical problems that the existing conductive fillers are unevenly distributed in the foaming system, resulting in unstable conductive performance, and the addition of conductive fillers affects the mechanical properties and lightweight characteristics of the foamed material, the present application provides a polymer foam material with a high conductive path and a preparation method thereof, wherein a highly conductive network is constructed to obtain a polymer foam material with both high conductivity and lightweight.

[0033] In a first aspect, an embodiment of the present application provides a method for preparing a polymer foam material with a high conductive path, comprising the following steps:

[0034] S1. The polymer matrix material, the compatibilizer, and the conductive filler are blended by internal mixing to obtain a blend, wherein the conductive filler is a mixture of silver nanowires and MXene;

[0035] S2. The blend is hot-pressed to obtain a foamed sheet;

[0036] S3. Foaming the foam sheet so that the conductive filler forms a continuous three-dimensional conductive path on the surface of the cell wall to obtain a polymer foam material with a high conductive path.

[0037] In the technical solution of the embodiment of the present application, by introducing silver nanowires (AgNWs) and MXene as conductive fillers in the polymer matrix material and forming a continuous three-dimensional conductive path on the surface of the pore wall, the conductive performance of the material is significantly improved. Silver nanowires have excellent conductivity and flexibility, and MXene has high conductivity and high specific surface area. The combination of the two can effectively improve the overall conductivity of the material. The mixing and blending process can ensure that the polymer matrix material, compatibilizer and conductive filler are evenly mixed, avoiding the agglomeration of the conductive filler, thereby forming a uniformly distributed conductive network in the foamed sheet. The hot pressing and foaming treatment processes can improve the mechanical properties of the material, so that it has good mechanical strength and flexibility while maintaining high conductivity, and is suitable for various application scenarios. The process flow of this method is simple, easy to operate, suitable for large-scale production, and can effectively reduce production costs and improve production efficiency.

[0038] Furthermore, in some embodiments, in step S1 , the polymer matrix material is one or more of polypropylene, polyethylene, polystyrene, and polylactic acid.

[0039] In the technical solution of the embodiment of the present application, the suitable polymer matrix material can not only form a good blend with the conductive filler and the compatibilizer, but also optimize the processing performance and mechanical properties of the material.

[0040] Furthermore, in some embodiments, the amount of MXene added is 3-8% of the mass of the polymer matrix material, and the mass ratio of MXene to silver nanowires is 1:(1.5-2).

[0041] In the technical solution of the embodiment of the present application, MXene has high conductivity and high specific surface area, and can form a good interface bond with the polymer matrix. The appropriate amount of addition can effectively improve the conductive properties of the material without excessively affecting the mechanical properties and processing properties of the material. Too low an amount of MXene added may not form a continuous conductive path, while too high an amount added may cause the dispersion of MXene in the matrix to deteriorate, affecting the overall performance of the material. Silver nanowires have excellent conductivity and flexibility, and can form a continuous conductive network at a low addition amount. When the mass ratio with MXene is within an appropriate range, it can ensure that the two form a synergistic effect in the material and jointly construct an efficient three-dimensional conductive path, which helps to balance the conductive contribution of the two and avoid excessive or insufficient single conductive fillers. The appropriate amount of MXene and silver nanowire addition can improve the conductive properties while maintaining the mechanical properties of the material. Specifically, the aspect ratio of the silver nanowire is 200 to 400:1; MXene is lamellar, with a thickness of 10 to 80 nm and a specific surface area of ​​20 to 30 m 2 / g.

[0042] Furthermore, in some embodiments, the compatibilizer is maleic anhydride grafted polypropylene, and the added amount is 8-12% of the mass of the polymer matrix material.

[0043] In the technical solutions of the embodiments of this application, the maleic anhydride groups in maleic anhydride-grafted polypropylene (PP-g-MAH) can chemically react or form strong interactions with the surface functional groups of the conductive filler, thereby enhancing the interfacial adhesion between the conductive filler and the polymer matrix, improving interfacial compatibility, and facilitating the uniform dispersion of the conductive filler in the polymer matrix, forming a more continuous and efficient conductive path. The appropriate addition amount can significantly improve interfacial compatibility, enhance the material's electrical conductivity and mechanical properties, and optimize processing performance.

[0044] Furthermore, in some embodiments, the temperature of the banburying blending is 160-180° C., and the banburying time is 10-20 min.

[0045] In the technical solution of the embodiment of the present application, excessive degradation of the polymer is avoided by internal mixing at a suitable temperature while ensuring that the polymer matrix is ​​fully melted, the conductive filler is evenly dispersed, and the compatibilizer acts effectively.

[0046] Furthermore, in some embodiments, in step S2, the temperature of the hot pressing treatment is 170-180°C, the pressure is 4-6 MPa, and the thickness of the foamed sheet is 0.5-2.0 mm.

[0047] In the technical solutions of the embodiments of this application, appropriate temperature and pressure can control the crystallinity and crosslinking degree of the blend, thereby affecting the nucleation and growth of cells during the foaming process, which is conducive to the formation of a uniform and dense cell structure. The dense sheet formed by hot pressing can make the conductive fillers (silver nanowires and MXene) more closely contacted within the sheet, creating favorable conditions for the formation of continuous three-dimensional conductive pathways during the subsequent foaming process.

[0048] Furthermore, in some embodiments, in step S3, the temperature of the foaming treatment is 170-180° C., the pressure is 8-12 MPa, and the holding time is 1-3 hours.

[0049] In the technical solution of the embodiment of the present application, the temperature of the foaming treatment can ensure that the foamed sheet remains in a molten state during the foaming process, which is beneficial to the nucleation and growth of the pores. At the same time, it also helps to control the growth rate of the pores and avoid the pores being too large or collapsed. Higher pressure can promote the nucleation of the pores and inhibit the excessive growth of the pores, thereby forming a uniform and dense pore structure. At the same time, higher pressure also helps to make the pore walls denser and improve the mechanical properties of the material. Appropriate holding time can ensure that the pores grow fully and stabilize the pore structure. Too short a holding time may lead to insufficient pore growth, while too long a holding time may lead to excessive pores or collapse. The uniform and dense pore structure can make the conductive fillers (silver nanowires and MXene) more evenly distributed on the surface of the pore wall, forming a continuous three-dimensional conductive path, thereby improving the conductive properties of the material.

[0050] Furthermore, in some embodiments, the pressure relief rate of the foaming treatment is 5 to 20 MPa / s.

[0051] In the technical solutions of the embodiments of this application, rapid pressure relief during the foaming process allows the cells to expand and shape rapidly, avoiding excessive cell growth or collapse caused by slow pressure relief, thereby achieving a uniform and dense cell structure. Rapid pressure relief also helps form continuous and complete conductive pathways on the cell walls, optimizing the conductive network and improving the consistency and reliability of material performance.

[0052] Furthermore, in some embodiments, the foaming agent of the foaming treatment is one or more of supercritical carbon dioxide, nitrogen, butane, and fluorocarbon compounds.

[0053] In the technical solutions of the embodiments of the present application, supercritical carbon dioxide (ScCO2), nitrogen, butane, and fluorocarbons (such as CFCs and HFCs) are used as foaming agents to achieve efficient foaming performance. The size and density of the foam cells can be controlled by adjusting the temperature, pressure, and amount of the foaming agent. The foaming agent has good compatibility with the polymer matrix and does not damage the matrix material. The use of these foaming agents can obtain a uniform and fine pore structure, which helps to improve the mechanical properties of the material. At the same time, the uniform pore structure helps the conductive filler form a continuous and complete conductive network on the pore wall, further improving the conductive properties of the material.

[0054] In a second aspect, an embodiment of the present application provides a polymer foam material with a high conductive path, which is prepared by the preparation method described in the first aspect.

[0055] In the technical solution of the embodiment of the present application, by optimizing material selection and preparation process, the prepared polymer foam material achieves high conductivity, uniform distribution and good mechanical properties. Its technical indicator of electrical conductivity ≥62S / m makes it have significant application value in the fields of electromagnetic shielding, thermal management and sensors.

[0056] Some specific examples are listed below. It should be noted that the examples described below are exemplary and are only used to explain the present application, and should not be construed as limiting the present application. Where specific techniques or conditions are not specified in the examples, the techniques or conditions described in the literature in this area or the product specifications are used. Reagents or instruments used without manufacturer's indication are all commercially available conventional products.

[0057] 1. Preparation method

[0058] Example 1

[0059] This embodiment provides a method for preparing a polymer foam material with a high conductive path, comprising the following steps:

[0060] S1. PP, AgNWs, MXene, and PP-g-MAH were dried at 70°C for 6 hours to remove moisture. 20 g of PP, 1.5 g of AgNWs, 1 g of MXene, and 2 g of PP-g-MAH were weighed and stirred in a beaker with a glass rod. The mixture was then added to a Haake rheometer and kneaded at 170°C for 15 minutes to obtain a blend.

[0061] S2. The blend was transferred to a preheated mold and hot-pressed into a 1 mm thick foam sheet at 175 ° C and 5 MPa by a flat vulcanizer;

[0062] S3. Cut the foam sheet into 2×3 cm sheets using a laser cutter, place the sheet in an autoclave, and fill it with ScCO2 for 10 minutes to expel the air from the autoclave. Finally, maintain a constant temperature and pressure of 175°C and 10 MPa for 2 hours. Rapidly release the pressure to allow the sheet to foam, resulting in a polymer foam material with a high conductive path.

[0063] Example 2

[0064] This embodiment provides a method for preparing a polymer foam material with a high conductive path. Compared with Example 1, the only difference is that the added amount of AgNWs is 2 g and the MXene is 1 g. Other parameters and conditions are basically the same as those in Example 1 and are not repeated here.

[0065] Example 3

[0066] This embodiment provides a method for preparing a polymer foam material with a high conductive path. Compared with Example 1, the only difference is that the mixing temperature is 160°C and the mixing time is 10 minutes. Other parameters and conditions are basically the same as those in Example 1 and are not repeated here.

[0067] Example 4

[0068] This embodiment provides a method for preparing a polymer foam material with a high conductive path. Compared with Example 1, the only difference is that the mixing temperature is 180°C and the mixing time is 20 minutes. Other parameters and conditions are basically the same as those in Example 1 and are not repeated here.

[0069] Example 5

[0070] This embodiment provides a method for preparing a polymer foam material with a high conductive path. Compared with Example 1, the only difference is that the foaming treatment temperature is 170°C, the pressure is 8 MPa, and the holding time is 1 hour. Other parameters and conditions are basically the same as those in Example 1 and are not repeated here.

[0071] Example 6

[0072] This embodiment provides a method for preparing a polymer foam material with a high conductive path. Compared with Example 1, the only difference is that the foaming treatment temperature is 180°C, the pressure is 12 MPa, and the holding time is 3 hours. Other parameters and conditions are basically the same as those in Example 1 and are not repeated here.

[0073] Comparative Example 1

[0074] Comparative Example 1 provides a method for preparing a polymer foam material with a high conductive path. Compared with Example 1, the only difference is that AgNWs and MXene are not added. Other parameters and conditions are basically the same as those in Example 1 and are not repeated here.

[0075] Comparative Example 2

[0076] Comparative Example 2 provides a method for preparing a polymer foam material with a high conductive path. Compared with Example 1, the only difference is that AgNWs are not added, the amount of MXene used is 2.5 g, and the other parameters and conditions are basically the same as those in Example 1 and are not repeated here.

[0077] Comparative Example 3

[0078] Comparative Example 3 provides a method for preparing a polymer foam material with a high conductive path. Compared with Example 1, the only difference is that MXene is not added, the amount of AgNWs used is 2.5 g, and the other parameters and conditions are basically the same as those in Example 1 and are not repeated here.

[0079] 2. Test Method

[0080] 1. SEM: Tested using thermal field emission scanning electron microscope;

[0081] 2. Mechanical properties: The tensile strength of the material is tested using an Instron electronic tensile testing machine;

[0082] 3. Conductivity: tested with a dual-electricity four-probe tester;

[0083] 4. Porosity: calculated using SEM cross-sectional image analysis.

[0084] 3. Analysis of test results of various embodiments and comparative examples

[0085] The test results of various embodiments and comparative examples are shown in Table 1.

[0086] Table 1 Test results of various embodiments and comparative examples

[0087]

[0088]

[0089] As can be seen from Table 1, the polypropylene foam material obtained in Example 1 has the best comprehensive effect of tensile strength, electrical conductivity and porosity. The uniform distribution of the conductive medium and the addition of the compatibilizer avoid the destruction of the pore structure. The material has high tensile strength. AgNWs and MXene form a continuous three-dimensional conductive network on the surface of the pore wall, which significantly improves the conductive performance of the material. Figures 1 to 3It can be seen that the present application forms a continuous and efficient conductive path through the combination of silver AgNWs and MXene. In the polypropylene foam material obtained in Example 1, the added AgNWs and MXene are well dispersed on the pore wall due to the effect of the compatibilizer PP-g-MAH, forming a continuous conductive path, which greatly improves the conductivity; in Comparative Example 1, since no AgNWs and MXene are added, the material cannot form a conductive network, and the mechanical strength is reduced; in Comparative Example 2, no AgNWs are added, resulting in the destruction of the integrity of the conductive network, which significantly reduces the conductive properties of the material; since the flaky structure of MXene has a certain enhancing effect on the mechanical properties of the material, no MXene is added in Comparative Example 3, resulting in a reduction in the mechanical strength of the material. In addition, the high specific surface area of ​​MXene allows it to be used as an effective heterogeneous nucleating agent. When the addition amount is too low or not added, the nucleation sites provided are insufficient, resulting in a reduction in the number of bubbles, thereby reducing the porosity.

[0090] It should be noted that the present application is not limited to the above-mentioned embodiments. The above-mentioned embodiments are merely examples, and any embodiments having substantially the same structure and effect as the technical concept within the scope of the present application are all included in the technical scope of the present application. In addition, without departing from the scope of the present application, any other embodiments that can be conceived by those skilled in the art and that combine some of the constituent elements in the embodiments are also included in the scope of the present application.

Claims

1. A method for preparing a polymer foam material with a high conductive path, characterized in that: The following steps are involved: S1. The polymer matrix material, the compatibilizer and the conductive filler are mixed by mixing to obtain a blend, wherein the conductive filler is a mixture of silver nanowires and MXene; S2. The blend is subjected to hot pressing to obtain a foamed sheet; S3. The foamed sheet is subjected to a foaming treatment so that the conductive filler forms a continuous three-dimensional conductive path on the surface of the cell wall, thereby obtaining a polymer foam material with a high conductive path.

2. The method for preparing a polymer foam material with a high conductive path according to claim 1, wherein: In step S1, the polymer matrix material is one or more of polypropylene, polyethylene, polystyrene, and polylactic acid.

3. The method for preparing a polymer foam material with a high conductive path according to claim 2, characterized in that: The added amount of the MXene is 3-8% of the mass of the polymer matrix material, and the mass ratio of the MXene to the silver nanowires is 1:(1.5-2).

4. The method for preparing a polymer foam material with a high conductive path according to claim 2, wherein: The compatibilizer is maleic anhydride grafted polypropylene, and the added amount is 8-12% of the mass of the polymer matrix material.

5. The method for preparing a polymer foam material with a high conductive path according to claim 4, characterized in that: The temperature of the banburying and blending is 160-180° C., and the banburying time is 10-20 minutes.

6. The method for preparing a polymer foam material with a high conductive path according to claim 1, wherein: In step S2, the temperature of the hot pressing treatment is 170-180°C, the pressure is 4-6 MPa, and the thickness of the foamed sheet is 0.5-2.0 mm.

7. The method for preparing a polymer foam material with a high conductive path according to claim 1, characterized in that: In step S3, the temperature of the foaming treatment is 170-180° C., the pressure is 8-12 MPa, and the pressure holding time is 1-3 hours.

8. The method for preparing a polymer foam material with a high conductive path according to claim 7, characterized in that: The pressure relief rate of the foaming treatment is 5 to 20 MPa / s.

9. The method for preparing a polymer foam material with a high conductive path according to claim 7, wherein: The foaming agent for the foaming treatment is one or more of supercritical carbon dioxide, nitrogen, butane, and fluorocarbon compounds.

10. A polymer foam material with a high conductive path, characterized in that: Prepared by the preparation method according to any one of claims 1 to 9.

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