High-density polyethylene conductive composite with isolated network and method of making same

Abstract

The application discloses a high-density polyethylene conductive composite material with isolated networks and a preparation method thereof, and the preparation method comprises the following steps: (1) uniformly and closely coating conductive fillers on the surface of high-density polyethylene powder by mechanical shearing in a pulverizing mixer to obtain a composite powder, wherein the conductive fillers are graphene or edge-oxidized graphene fillers; and (2) hot-pressing the composite powder to form a three-dimensional conductive network in the material, thereby obtaining the high-density polyethylene conductive composite material with isolated networks. According to the application, the adverse influence of the isolated structure on the mechanical properties is minimized under high conductivity, the efficiency of mutual contact of the conductive fillers is improved, and the insulating gap between adjacent conductive fillers is reduced. Moreover, a stronger interface interaction is built between the polymer particles and the conductive fillers, and a polyethylene material with excellent conductivity and good mechanical properties is obtained.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of conductive polymers, in particular to a high-density polyethylene conductive composite material with a segregated network and a preparation method thereof. BACKGROUND

[0002] Polyethylene has been widely used due to its light weight, easy molding and processing, and high cost performance. However, due to its electrical insulation, the surface of polyethylene products is prone to static accumulation during use, which can cause harm. By blending conductive fillers with insulating polymers to prepare conductive polymer composites (CPC), stable and permanent antistatic properties can be obtained, which is the simplest and most effective method to eliminate static hazards. For CPC prepared by traditional double screw extrusion and injection molding methods, conductive nanofillers are randomly distributed in the matrix, and a large amount of conductive nanofillers need to be added to obtain sufficient conductivity, which leads to serious deterioration of the mechanical and processing properties of CPC, and has no economic effect. Therefore, reducing the conductive threshold and designing an effective conductive network are the key to preparing high-performance CPC.

[0003] Constructing a three-dimensional (3D) segregated carbon-based conductive nanofiller network in a polymer matrix is an effective strategy for preparing CPC with excellent conductivity. For segregated conductive polymer composites (s-CPC), carbon-based conductive nanofillers are not uniformly distributed throughout the polymer matrix, but are limited to the boundaries between polymer domains and are distributed along specific pathways, thereby forming a continuous conductive network. Compared with ordinary CPC, this specific distribution of conductive fillers on the interface of polymer domains results in a high-efficiency transport network at a very low conductive threshold, which helps to develop new high-performance CPC and is widely used in high-performance antistatic, EMI shielding and sensing materials.

[0004] However, s-CPC still faces many challenges. Although a good segregated structure can be constructed by hot pressing polymer mixed particles coated with carbon-based conductive nanofillers, the selective distribution of nanofillers often leads to poor interfacial interaction between nanofillers and the polymer matrix, and nanofillers are severely aggregated on the segregated path to form abundant microdefects. The mechanical properties of s-CPC are much lower than those of ordinary CPC composites with random distribution of fillers, especially the elongation at break, which seriously hinders its application in many fields. SUMMARY

[0005] The present application aims to provide a high-density polyethylene conductive composite material with a segregated network and a preparation method thereof, which can prepare a polyethylene material with excellent conductive performance and good mechanical properties.

[0006] In one aspect of the present application, the present application provides a preparation method of high-density polyethylene conductive composite material with isolated network, which realizes high conductive capacity of the material at low filler content by constructing a three-dimensional conductive network with isolated structure, and is prepared by using a "mechanical shearing mixing coating-high temperature pressing" method. According to an embodiment of the present application, the method comprises the following steps:

[0007] (1) obtaining a composite powder by uniformly and tightly coating a conductive filler, which is graphene (GNP) or edge-oxidized graphene filler, on the surface of high-density polyethylene powder (HDPE) in a pulverizing mixer through mechanical shearing;

[0008] (2) hot-pressing the composite powder to form a three-dimensional conductive network in the material, thereby obtaining the high-density polyethylene conductive composite material with isolated network.

[0009] In addition, the preparation method of high-density polyethylene conductive composite material with isolated network according to the above-mentioned embodiments of the present application can also have the following additional technical features:

[0010] In some embodiments of the present application, in the step (1), the edge-oxidized graphene filler is prepared as follows: graphene is subjected to edge oxidation modification by using nitric acid and potassium permanganate to obtain edge-oxidized graphene, and then a conductive polymer polyaniline is in-situ polymerized on the surface of the edge-oxidized graphene, thereby obtaining the edge-oxidized graphene filler. The present application prepares the edge-oxidized graphene filler (PANI-EOG) in which polyaniline is in-situ polymerized, in order to further improve the mechanical properties of the polyethylene conductive composite material with isolated network at high conductivity. The coating effect of the conductive filler on the surface of the polymer particles is improved, the efficiency of mutual contact of the conductive fillers is improved, and the insulating gap between adjacent conductive fillers is reduced. And a stronger interfacial interaction is constructed between the polymer particles and the carbon-based nanofiller, which significantly improves the mechanical properties of the s-CPC while maintaining the high conductive isolated network.

[0011] In some embodiments of the present application, the edge-oxidized graphene is prepared as follows: graphene is added into a KMnO4 / HNO3 solution for chemical oxidation, and then centrifuged, washed, filtered and dried to obtain the edge-oxidized graphene.

[0012] In some embodiments of the present application, the concentration of KMnO4 in the KMnO4 / HNO3 solution is 2.0-4.0 mg / ml;

[0013] The mass ratio of KMnO4 to graphene is 0.20-0.25; the temperature of the chemical oxidation is 50-55 DEG C, the stirring speed is 800-1000 rpm, the reaction time is 24-36 h; the centrifugal speed is 5000-8000 rpm, the centrifugal time is 8-10 min; the washing is performed by using distilled water; and the drying temperature is 55-60 DEG C, and the drying time is 24-36 h.

[0014] In some embodiments of the present application, the specific steps of in-situ polymerization of conductive polymer polyaniline on the edge-oxidized graphene surface are as follows: the edge-oxidized graphene is added into a hydrochloric acid solution to obtain a uniform EOG dispersion, an aniline monomer is added into the EOG dispersion to mix uniformly, then an APS solution is added drop by drop, and after the reaction is completed, filtration, washing and drying are performed to obtain the edge-oxidized graphene filler.

[0015] In some embodiments of the present application, the concentration of the hydrochloric acid solution is 1-1.1 mol / L; the mass ratio of the edge-oxidized graphene to the aniline monomer is 0.3-1; the reaction temperature is 20-25 DEG C, the reaction time is 6-9 h, the drying temperature is 55-60 DEG C, and the drying time is 24-36 h.

[0016] In some embodiments of the present application, the step (1) is specifically as follows: a pulverizing mixer is used to shear mix 1wt%-3wt% of conductive fillers and 50-400 mu m of high-density polyethylene powder at a speed of 34000-40000 rpm for 2-3 min, and GNPs are coated on the surface of the HDPE powder by using electrostatic adsorption to prepare a composite powder.

[0017] In some embodiments of the present application, in the step (2), the temperature of the hot-pressing forming is 132-147 DEG C, the hot-pressing pressure is 2-12 MPa, the hot-pressing time is 8-10 min, and after the hot-pressing is completed, the pressure is removed to allow the mold to cool to room temperature naturally.

[0018] In another aspect of the present application, the present application provides a high-density polyethylene conductive composite material with an isolation network, which is prepared by the preparation method of the high-density polyethylene conductive composite material with an isolation network.

[0019] Compared with the prior art, the present application has the following beneficial effects:

[0020] 1) The coating effect of the conductive coating on the polymer particle surface, the sufficient dispersion level of the conductive filler in the isolation network, the continuity and density of the isolation conductive path, and the interfacial adhesion strength between the conductive filler and the polymer particles are key factors affecting the conductivity and mechanical properties of s-CPC. To obtain the best overall performance and minimize the adverse effects of the isolation structure on mechanical properties under high conductivity, this invention optimizes processing variables (e.g., molding temperature, molding pressure, polymer particle size, etc.). While constructing a tight isolation network, it avoids severe migration of carbon-based nanofillers into the internal matrix, thus achieving the preparation of polyethylene conductive composite materials with good conductivity and mechanical properties at low conductive filler content.

[0021] 2) This invention prepares PANI-EOG through simple conductive filler modification, significantly improving the mechanical properties of conductive composite materials while maintaining high conductivity. This method is applicable to different insulating conductive polymer composite materials, broadening their applications in antistatic, electromagnetic shielding, and sensing fields.

[0022] 3) This patent is easy to implement, the equipment is simple to maintain and clean, and there are no stringent requirements for environmental conditions. Attached Figure Description

[0023] Figure 1 The above are process flow diagrams for preparing polyethylene conductive composite materials with isolation structures in Examples 1-18 of this invention.

[0024] Figure 2 The image shows a SEM image of PANI-EOG prepared in Example 21 of this invention.

[0025] Figure 3 a is a SEM image of the surface of the GNP@HDPE composite powder prepared in Example 17 of this invention. Figure 3 b is a SEM image of the surface of the PANI-EOG@HDPE composite powder prepared in Example 21 of this invention;

[0026] Figure 4 Optical microscope images of high-density polyethylene conductive composite materials with isolation networks prepared in the embodiments of the present invention, a is GNP / HDPE prepared in Example 17, and b is PANI-EOG / HDPE prepared in Example 21;

[0027] Figure 5 The images show cross-sectional SEM images of the high-density polyethylene conductive composite material with an isolation network prepared according to the embodiments of the present invention. a is GNP / HDPE prepared in Example 17, and b is PANI-EOG / HDPE prepared in Example 21. Detailed Implementation

[0028] The technical solutions in the embodiments of the present application will be clearly and completely described with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative effort fall within the protection scope of the present application.

[0029] The raw materials used in the embodiments of the present application are as follows: conductive graphene (longitudinal size 2-10 μm, Sinopec (Beijing) Chemical Research Institute Co., Ltd.), aniline (≥99%, Araldin), potassium permanganate (≥99.5%, Yonghua Chemical Technology), concentrated nitric acid (68%, Kunshan Jingke), concentrated hydrochloric acid (38%, Kunshan Jincheng), high-density polyethylene powder (melting point 132℃, density 0.952 g / cm 3 , melt index 0.25 g / 10 min, Dongguan Zhangmutou Taige Plastic), ammonium persulfate (≥98%, Shanghai Lingfeng).

[0030] The performance of the polyethylene conductive composite standard samples obtained in Examples 1-21 was tested according to the following standards: tensile test according to GB / T1040.3-2006; surface resistivity test according to ANSI / ESD Association standard using Trek 152-1 surface resistance meter; all samples were tested at 23℃ for 24 h, and the test temperature was 23℃.

[0031] Example 1

[0032] The preparation method of the high-density polyethylene conductive composite with an isolated network, as shown in Figure 1 , comprises the following steps:

[0033] (1) Preparation of GNP@HDPE particles

[0034] Polyethylene powder with a particle size of 200 μm and graphene nanosheets were placed in a crushing mixer, the mass fraction of graphene was controlled to be 1%, and shearing mixing was performed at a speed of 34000 rpm for 3 min to obtain polyethylene powder GNP@HDPE coated with 1% conductive filler.

[0035] (2) Preparation of GNP / HDPE with an isolated structure by hot pressing

[0036] The above GNP@HDPE composite powder was hot-pressed, the hot-pressing temperature was 132℃, the hot-pressing pressure was 8 MPa, and the pressure was maintained for 8 min, then the pressure was removed and the mold was naturally cooled to room temperature to prepare GNP / HDPE with an isolated network.

[0037] Example 2

[0038] The preparation method of the high-density polyethylene conductive composite material with an isolated network, which is only different from example 1 in that in the step (1), the mass fraction of graphene is controlled to be 2%, and the polyethylene powder coated with 1% conductive filler is prepared.

[0039] Example 3

[0040] The preparation method of the high-density polyethylene conductive composite material with an isolated network, which is only different from example 1 in that in the step (1), the mass fraction of graphene is controlled to be 3%, and the polyethylene powder coated with 3% conductive filler is prepared.

[0041] Example 4

[0042] The preparation method of the high-density polyethylene conductive composite material with an isolated network, which is only different from example 3 in that in the step (2), the pressure of the hot-pressing process is 4 MPa.

[0043] Example 5

[0044] The preparation method of the high-density polyethylene conductive composite material with an isolated network, which is only different from example 3 in that in the step (2), the pressure of the hot-pressing process is 6 MPa.

[0045] Example 6

[0046] The preparation method of the high-density polyethylene conductive composite material with an isolated network, which is only different from example 3 in that in the step (2), the pressure of the hot-pressing process is 10 MPa.

[0047] Example 7

[0048] The preparation method of the high-density polyethylene conductive composite material with an isolated network, which is only different from example 3 in that in the step (2), the pressure of the hot-pressing process is 12 MPa.

[0049] Example 8

[0050] The preparation method of the high-density polyethylene conductive composite material with an isolated network, which is only different from example 3 in that in the step (2), the temperature of the hot-pressing process is 137℃.

[0051] Example 9

[0052] The preparation method of the high-density polyethylene conductive composite material with an isolated network, which is only different from example 3 in that in the step (2), the temperature of the hot-pressing process is 142℃.

[0053] Example 10

[0054] A method for preparing a high-density polyethylene conductive composite material with an isolated network, which differs from example 3 only in that in step (2), the temperature of the hot-pressing process is 147°C.

[0055] Example 11

[0056] A method for preparing a high-density polyethylene conductive composite material with an isolated network, which differs from example 8 only in that in step (2), the pressure of the hot-pressing process is 6 MPa.

[0057] Example 12

[0058] A method for preparing a high-density polyethylene conductive composite material with an isolated network, which differs from example 8 only in that in step (2), the pressure of the hot-pressing process is 4 MPa.

[0059] Example 13

[0060] A method for preparing a high-density polyethylene conductive composite material with an isolated network, which differs from example 8 only in that in step (2), the pressure of the hot-pressing process is 2 MPa.

[0061] Example 14

[0062] A method for preparing a high-density polyethylene conductive composite material with an isolated network, which differs from example 9 only in that in step (2), the pressure of the hot-pressing process is 6 MPa.

[0063] Example 15

[0064] A method for preparing a high-density polyethylene conductive composite material with an isolated network, which differs from example 9 only in that in step (2), the pressure of the hot-pressing process is 4 MPa.

[0065] Example 16

[0066] A method for preparing a high-density polyethylene conductive composite material with an isolated network, which differs from example 9 only in that in step (2), the pressure of the hot-pressing process is 2 MPa.

[0067] Example 17

[0068] A method for preparing a high-density polyethylene conductive composite material with an isolated network, which differs from example 15 only in that in step (1), the particle size of the polyethylene powder is 50 μm.

[0069] As Figure 3 shown in FIG. a, GNP is coated on the surface of HDPE, and there is a gap between GNP fillers.

[0070] AsFigure 4 HDPE particles were isolated by GNPs, and GNPs were uniformly distributed between HDPE particles to form GNPs / HEDPE with isolated three-dimensional conductive network, and some isolated paths were agglomerated by conductive fillers.

[0071] As shown in FIG. 1a, the rough cross-section showed a typical isolated structure, and GNPs were selectively distributed at the interface of HDPE particles to form conductive paths. Some holes and cracks appeared at the interface between adjacent particles, indicating that the interface interaction was relatively poor, resulting in relatively poor mechanical properties of the composite material. Figure 5 As shown in FIG. 1a, the rough cross-section showed a typical isolated structure, and GNPs were selectively distributed at the interface of HDPE particles to form conductive paths. Some holes and cracks appeared at the interface between adjacent particles, indicating that the interface interaction was relatively poor, resulting in relatively poor mechanical properties of the composite material.

[0072] Example 18

[0073] A method for preparing high-density polyethylene conductive composite material with isolated network, which is different from example 15 only in that in step (1), the particle size of polyethylene powder is 400 μm,

[0074] The related processing parameters of high-density polyethylene conductive composite material with isolated network in examples 1-18 are shown in Table 1:

[0075] Table 1 Related processing parameters of high-density polyethylene conductive composite material with isolated network in examples 1-18

[0076]

[0077]

[0078] The high-density polyethylene conductive composite material with isolated network prepared in examples 1-18 was tested for electrical conductivity and mechanical properties, and the test results are shown in Table 2.

[0079] Table 2 Electrical conductivity and mechanical properties of isolated conductive polyethylene in examples 1-18

[0080]

[0081]

[0082] The results of Tables 1 and 2 show that Examples 1-3 reveal the effect of different GNP conductive filler contents on the electrical conductivity and mechanical properties of the isolated conductive polyethylene, as the mass percentage of the conductive filler increases from 1 wt% to 3 wt%, the electrical conductivity of the conductive polyethylene improves, and the mechanical properties decrease; Examples 4-7 reveal the effect of different hot-pressing pressures on the electrical conductivity and mechanical properties of the isolated conductive polyethylene, high pressure can reduce the amount of microvoids between the conductive particles, produce a tight isolated network, and appropriately improve the mechanical properties and electrical conductivity. However, too high a pressure can cause the melt of the main polymer to break, reduce the aspect ratio of the conductive filler, and decompose the isolated conductive network into individual conductive channels, thereby reducing the electrical conductivity of the conductive polyethylene; Examples 8-10 reveal the effect of different hot-pressing temperatures on the electrical conductivity and mechanical properties of the isolated conductive polyethylene, too high a processing temperature reduces the melt viscosity of the main polymer, and significant intermixing occurs between the conductive filler and the polymer, hindering the formation of the isolated network, thereby reducing the electrical conductivity of the conductive polyethylene; Examples 11-16 reveal that, with reference to the above-mentioned temperature and pressure effects, the pressure applied when increasing the processing temperature should be reasonable to ensure that the conductive filler and the polymer particles are tightly packed without damaging their geometric dimensions, and the best comprehensive properties of the conductive polyethylene are obtained by adjusting different hot-pressing temperatures and pressures; Examples 17-18 reveal the effect of different particle sizes of the HDPE powder on the mechanical properties and electrical conductivity of the isolated conductive polyethylene, and by reducing the particle size of the HDPE powder, the isolated conductive path can be refined, the aggregation of a large amount of conductive filler can be avoided, the density of the isolated conductive path can be increased, and thus the mechanical properties and electrical conductivity of the conductive polyethylene can be improved.

[0083] Example 19

[0084] A method for preparing a high-density polyethylene conductive composite material with an isolated network, comprising the following steps:

[0085] (1) Preparation of PANI-EOG@HDPE particles

[0086] a. Preparation of EOG

[0087] 4.0 g of GNP was added to 200 mL of a KMnO4 / HNO3 solution (68% nitric acid solution:H2O=1:3) containing 0.8 g of KMnO4, and the chemical oxidation was continuously stirred at 800 rpm for 24 h at 50°C to obtain edge-oxidized graphene EOG. The reaction product was centrifuged at 5000 rpm for 10 min, and then repeatedly washed with distilled water to remove residual acid. The product was filtered, dried in an oven at 60°C for 24 h, and ground into powder in a mortar to obtain EOG for standby use.

[0088] b. Preparation of PANI-EOG

[0089] A 1 mol / L hydrochloric acid solution was prepared by dissolving 20 ml of 38% hydrochloric acid in 220 ml of deionized water. Then, 0.7464 g of EOG was added to 120 ml of the 1 mol / L hydrochloric acid solution and ultrasonically dispersed for 30 min to obtain a uniform EOG dispersion. Then, 0.024 mol of aniline (An) 2.2 ml of monomer was added to the EOG dispersion (EOG:An monomer mass ratio = 1:3), and ultrasonic treatment was continued for 30 min to ensure that they were completely and uniformly mixed. At the same time, 5.4768 g of ammonium persulfate (APS) was added to the remaining 120 ml of the hydrochloric acid solution, and magnetic stirring was performed for 30 min to obtain an APS solution (monomer: initiator = 1:1). The prepared APS solution was added dropwise to the An / EOG mixture under water bath conditions, the water bath temperature was maintained at 25°C, and after 9 h of reaction, the product solution was filtered and washed until the filtrate became colorless. The filtered product was dried in an oven at 60°C for 24 h, and was ground with a mortar to obtain PANI-EOG.

[0090] c. The polyethylene powder with a particle size of 50 μm and 3% PANI-EOG by mass fraction were placed in a crushing stirrer, and shearing mixing was performed at a speed of 34,000 rpm for 3 min to obtain polyethylene powder coated with 3% conductive filler, PANI-EOG@HDPE.

[0091] (2) Preparation of PANI-EOG / HDPE with an isolated structure by hot pressing:

[0092] The PANI-EOG@HDPE particles were hot-pressed, the hot-pressing process conditions were a temperature of 142°C, a pressure of 4 MPa, and a holding time of 8 min, and then the pressure was removed and the mold was naturally cooled to room temperature to prepare PANI-EOG / HDPE with an isolated network.

[0093] Example 20

[0094] The preparation method of the high-density polyethylene conductive composite material with an isolated network differs from that of Example 19 only in that in step (1) b, the EOG:An monomer mass ratio = 1:2.

[0095] Example 21

[0096] The preparation method of the high-density polyethylene conductive composite material with an isolated network differs from that of Example 19 only in that in step (1) b, the EOG:An monomer mass ratio = 1:1.

[0097] As shown in FIG. 1, the rod-like PANI is uniformly polymerized on the surface of EOG through π-π conjugation and electrostatic adsorption. Figure 2

[0098] As shown in FIG. 2, the rod-like PANI is uniformly polymerized on the surface of EOG through π-π conjugation and electrostatic adsorption. Figure 3 ​As shown in Figure b, the PANI-EOG is tightly coated on the surface of HDPE, and the adjacent EOGs are overlapped with each other.

[0099] As shown in Figure b, the PANI-EOG is tightly coated on the surface of HDPE, and the adjacent EOGs are overlapped with each other. Figure 4 As shown in Figure b, the HDPE particles are isolated by the PANI-EOG, and the PANI-EOG is uniformly distributed between the HDPE particles, forming a PANI-EOG / HDPE with a three-dimensional conductive network.

[0100] As shown in Figure b, the PANI-EOG is tightly coated on the surface of HDPE, and the adjacent EOGs are overlapped with each other. Figure 5 As shown in Figure b, the smooth cross-section presents an improved isolation structure, and the PANI-EOG is selectively distributed at the interface of the HDPE particles to form a conductive path. There are no holes and cracks at the interface between adjacent particles, indicating that the interface interaction is strong, resulting in relatively good mechanical properties of the composite material.

[0101] The related processing parameters for preparing the high-density polyethylene conductive composite material with an isolation network in Examples 19-21 are shown in Table 3.

[0102] Table 3 Related processing parameters for preparing the high-density polyethylene conductive composite material with an isolation network in Examples 19-21

[0103]

[0104] The conductive properties and mechanical properties of the high-density polyethylene conductive composite material with an isolation network prepared in Examples 19-21 were tested, and the test results are shown in Table 4.

[0105] Table 4 Conductive properties and mechanical properties of the high-density polyethylene conductive composite material prepared in Examples 19-21

[0106] Sample Surface resistivity (Ω) Tensile strength (MPa) Elongation at break (%) Example 19 5.22 x 10 5 ]]> 22.9 97.0 Example 20 8.43 x 10 4 ]] 22.7 116.7 Example 21 6.56 x 10 3 ]] 23.1 235.4

[0107] As shown by the results in Tables 3 and 4, Examples 19-21 reveal the influence of PANI-EOG with different EOG:An ratios on the conductive properties and mechanical properties of the isolation conductive polyethylene. PANI, as an intrinsic conductive polymer, can act as an adhesive and a conductive bridge, enhance the coating of EOG on the surface of HDPE powder, and promote the contact between EOG and the formation of a conductive bridge (i.e., a PANI phase) between EOG to improve the conductive network. At the same time, PANI can also enhance the interaction between the conductive filler and the HDPE interface to improve the mechanical properties. Compared with the conductive polyethylene prepared in Example 17 using GNP as the conductive filler, the mechanical and conductive properties of the conductive polyethylene prepared in Example 21 using PANI-EOG as the conductive filler are significantly improved.

[0108] The above merely illustrates and describes the present application, and those skilled in the art can make various modifications or supplements to the described specific embodiments or adopt similar ways to replace, as long as the modifications or supplements do not deviate from the structure of the present application or exceed the scope defined by the present claims, and should belong to the protection scope of the present application.

Claims

1. Process for the preparation of high density polyethylene conductive composites with isolated networks, characterized in that, The method comprises the following steps: (1) obtaining a composite powder by uniformly and tightly coating a conductive filler on the surface of high-density polyethylene powder in a pulverizing mixer through mechanical shearing, wherein the conductive filler is an edge-oxidized graphene filler; wherein the edge-oxidized graphene filler is prepared by edge-oxidizing graphene using nitric acid and potassium permanganate to obtain edge-oxidized graphene, and then in-situ polymerizing a conductive polymer polyaniline on the surface of the edge-oxidized graphene, and the mass ratio of the edge-oxidized graphene to aniline monomer is 0.5-1; the edge-oxidized graphene is prepared by adding graphene into a KMnO4 / HNO3 solution for chemical oxidation, and then centrifuging, washing, filtering and drying to obtain the edge-oxidized graphene; the concentration of KMnO4 in the KMnO4 / HNO3 solution is 2.0-4.0 mg / ml; the mass ratio of KMnO4 to graphene is 0.20-0.25; the temperature of the chemical oxidation is 50-55 ℃, the stirring speed is 800-1000 rpm, and the reaction time is 24-36 h; (2) hot-pressing the composite powder to form a three-dimensional conductive network in the material, thereby obtaining the high-density polyethylene conductive composite material with an isolation network.

2. The method according to claim 1, wherein: the centrifugal speed is 5000-8000 rpm, and the centrifugal time is 8-10 min; the washing is performed using distilled water; the drying temperature is 55-60 ℃, and the drying time is 24-36 h.

3. The method for preparing the high-density polyethylene conductive composite material with an isolation network according to claim 1, characterized in that: The specific steps of in-situ polymerizing a conductive polymer polyaniline on the surface of the edge-oxidized graphene are as follows: adding the edge-oxidized graphene into a hydrochloric acid solution to obtain a uniform EOG dispersion, adding aniline monomer into the EOG dispersion to mix uniformly, then adding APS solution drop by drop, filtering and washing after the reaction is completed, and drying to obtain the edge-oxidized graphene filler.

4. The method according to claim 3, wherein: the concentration of the hydrochloric acid solution is 1-1.1 mol / L; the reaction temperature is 20-25 ℃, the reaction time is 6-9 h, the drying temperature is 55-60 ℃, and the drying time is 24-36 h.

5. The method of making a high-density polyethylene conductive composite with isolated networks of claim 1, wherein: In step (1), a pulverizing mixer is used to shear mix 1 wt%-3 wt% of the conductive filler and 50-400 μm of high-density polyethylene powder at a speed of 34000-40000 rpm for 2-3 min, and GNPs are coated on the surface of the HDPE powder by electrostatic adsorption to obtain the composite powder.

6. The method of making a high-density polyethylene conductive composite with an isolated network of claim 1, wherein: In step (2), the hot-pressing temperature is 132-147 ℃, the hot-pressing pressure is 2-12 MPa, the hot-pressing time is 8-10 min, and the mold is naturally cooled to room temperature after the hot-pressing is completed.

7. A process for the preparation of a high-density polyethylene conductive composite with a barrier network according to any one of claims 1 to 6, wherein the high-density polyethylene conductive composite with a barrier network is prepared.

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