Rosin amine modified tungsten carbide, its preparation method and application, composite conductive filler and its application, conductive rubber and its preparation method

Abstract

The present invention provides rosin amine modified tungsten carbide and its preparation method and application, a composite conductive filler and its application, and a conductive rubber and its preparation method, relating to the technical field of rubber. The rosin amine modified tungsten carbide provided by the present invention comprises tungsten carbide and rosin amine adsorbed on the surface of the tungsten carbide. The rosin amine modified tungsten carbide is not easily oxidized, and when used as a conductive filler in rubber, it can significantly improve the conductive performance of the rubber. Polypyrrole has excellent conductivity. The present invention uses rosin amine modified tungsten carbide and polypyrrole as a composite conductive filler in rubber, which can further improve the conductive performance of the rubber. When styrene-butadiene rubber, natural rubber, carbon black, zinc oxide, stearic acid, antioxidant, environmental aromatic oil, sulfur, N,N-dicyclohexyl-2-benzothiazole sulfenamide and N-nitrosodiphenylamine are used in combination, the obtained conductive rubber has excellent comprehensive properties such as conductive performance, mechanical performance, processing performance and weather resistance, and has a long service life.

Description

Technical Field

[0001] The present invention relates to the technical field of rubber, and specifically relates to rosin amine modified tungsten carbide and its preparation method and application, composite conductive filler and its application, and conductive rubber and its preparation method. Background Art

[0002] As a kind of composite conductive polymer material, conductive rubber is made of a rubber elastomer matrix plus a conductive filler, which not only retains the elasticity of the matrix rubber but also has the conductivity of the conductive filler. Since the material can adjust the electrical and mechanical properties of the material within a large range according to the use requirements, and has the advantages of light weight, easy processing and molding, low cost, and mature technology, it has developed rapidly in recent years and has become a new type of functional material. Metal conductive powders such as copper, silver, iron, and aluminum are commonly used conductive fillers for conductive rubber. After adding the above metal conductive powder fillers, the volume resistivity of the conductive rubber can reach several thousand or several hundred ohm-centimeters. However, the above metal conductive powders are prone to oxidation corrosion, which in turn affects the conductive performance of the conductive rubber. Summary of the Invention

[0003] In view of this, the purpose of the present invention is to provide rosin amine modified tungsten carbide and its preparation method and application, composite conductive filler and its application, and conductive rubber and its preparation method. The rosin amine modified tungsten carbide provided by the present invention is not easily oxidized, and when used as a conductive filler in rubber, it can significantly improve the conductive performance of the rubber.

[0004] In order to achieve the above invention purpose, the present invention provides the following technical solutions:

[0005] The present invention provides a kind of rosin amine modified tungsten carbide, which includes tungsten carbide and rosin amine adsorbed on the surface of the tungsten carbide.

[0006] The present invention provides a preparation method of the rosin amine modified tungsten carbide as described in the above technical solution, including the following steps:

[0007] Mix the rosin amine aqueous solution with tungsten carbide, carry out electrostatic adsorption treatment and then solid-liquid separation, and dry the obtained solid component to obtain rosin amine modified tungsten carbide.

[0008] Preferably, the mass ratio of tungsten carbide to rosin amine in the rosin amine aqueous solution is 1:7.5 - 20.

[0009] Preferably, the electrostatic adsorption is carried out under ultrasonic conditions, the power of the ultrasonic is 120 - 1000W, and the time is 7 - 9h.

[0010] The present invention provides the application of the rosin amine modified tungsten carbide as described in the above technical solution or the rosin amine modified tungsten carbide prepared by the preparation method as described in the above technical solution as a conductive filler in rubber.

[0011] The present invention provides a composite conductive filler, comprising rosin amine modified tungsten carbide and polypyrrole; the rosin amine modified tungsten carbide is the rosin amine modified tungsten carbide described in the above technical solution or the rosin amine modified tungsten carbide prepared by the preparation method described in the above technical solution.

[0012] Preferably, the mass ratio of the rosin amine modified tungsten carbide to the polypyrrole is 0.5-2:10-15.

[0013] The present invention provides the application of the composite conductive filler described in the above technical solution in rubber.

[0014] The present invention provides a conductive rubber, comprising the following parts by mass of raw materials for preparation: 70-90 parts of styrene-butadiene rubber, 10-30 parts of natural rubber, 20-30 parts of carbon black, 3-5 parts of zinc oxide, 10.5-17 parts of the composite conductive filler described in the above technical solution, 1-3 parts of stearic acid, 2-5 parts of antioxidant, 10-25 parts of environmental protection aromatic oil, 1.5-2.5 parts of sulfur, 0.5-1 part of N,N-dicyclohexyl-2-2-benzothiazole sulfenamide, and 0.1-0.5 part of N-nitrosodiphenylamine.

[0015] The present invention provides a preparation method of the conductive rubber described in the above technical solution, comprising the following steps:

[0016] Mix styrene-butadiene rubber, natural rubber, carbon black, zinc oxide, composite conductive filler, stearic acid, antioxidant, environmental protection aromatic oil, sulfur, N,N-dicyclohexyl-2-2-benzothiazole sulfenamide and N-nitrosodiphenylamine, and perform co-extrusion to obtain the conductive rubber.

[0017] The present invention provides a rosin amine modified tungsten carbide, comprising tungsten carbide and rosin amine adsorbed on the surface of the tungsten carbide. In the rosin amine modified tungsten carbide provided by the present invention, the chemical property of tungsten carbide is stable, and the Zeta potential of the rosin amine modified tungsten carbide in an aqueous solution is positive, which can improve the electrostatic assembly ability of tungsten carbide. The rosin amine modified tungsten carbide used as a conductive filler in rubber can significantly improve the conductive performance of rubber and has good application prospects in rubber.

[0018] The present invention provides a method for preparing rosin amine modified tungsten carbide according to the above technical solution, which includes the following steps: mixing an aqueous solution of rosin amine with tungsten carbide, performing electrostatic adsorption treatment and then separating the solid and liquid phases, and drying the obtained solid component to obtain rosin amine modified tungsten carbide. The Zeta potential of the aqueous solution of rosin amine is positive, and the Zeta potential of tungsten carbide powder in the aqueous solution is negative. The present invention uses the aqueous solution of rosin amine to perform electrostatic adsorption treatment on tungsten carbide powder, so that rosin amine is adsorbed on the surface of tungsten carbide powder to modify tungsten carbide, making the Zeta potential of the rosin amine modified tungsten carbide in the aqueous solution positive and improving the electrostatic assembly ability of tungsten carbide. The preparation method provided by the present invention is simple in operation, green and environmentally friendly with water as the solvent, low in production cost, and suitable for industrial production.

[0019] The present invention provides a composite conductive filler, which includes rosin amine modified tungsten carbide and polypyrrole; the rosin amine modified tungsten carbide is the rosin amine modified tungsten carbide according to the above technical solution or the rosin amine modified tungsten carbide prepared by the preparation method according to the above technical solution. The rosin amine modified tungsten carbide is not easily oxidized, and polypyrrole has excellent conductivity. The present invention uses rosin amine modified tungsten carbide and polypyrrole as the composite conductive filler and applies it to rubber, which can significantly improve the conductive performance of rubber and has good application prospects in rubber.

[0020] The present invention provides a conductive rubber, which includes the following raw materials for preparation in parts by mass: 70-90 parts of styrene-butadiene rubber, 10-30 parts of natural rubber, 20-30 parts of carbon black, 3-5 parts of zinc oxide, 10.5-17 parts of the composite conductive filler according to the above technical solution, 1-3 parts of stearic acid, 2-5 parts of antioxidant, 10-25 parts of environmentally friendly aromatic oil, 1.5-2.5 parts of sulfur, 0.5-1 part of N,N-dicyclohexyl-2-2-benzothiazole sulfenamide, and 0.1-0.5 part of N-nitrosodiphenylamine. The present invention uses styrene-butadiene rubber and natural rubber as the main materials. The combination of natural rubber and styrene-butadiene rubber can improve the comprehensive performance and service life of rubber; uses rosin amine modified tungsten carbide and polypyrrole as the composite conductive filler, and carbon black increases the wear resistance and tensile performance of rubber; zinc oxide reacts with N,N-dicyclohexyl-2-2-benzothiazole sulfenamide (accelerator) to form a zinc salt complex, and 2n with empty orbitals 2+The particles have strong polarization ability and are easy to promote the cleavage of sulfur cyclic molecules to facilitate rubber vulcanization; stearic acid can significantly reduce the viscosity of the rubber compound, improve the processing performance, and can significantly increase the plasticity of the rubber compound; the antioxidant can extend the service life of rubber products; the environmentally friendly aromatic oil can soften and plasticize the rubber; sulfur as a crosslinking agent can change the heat resistance of the rubber; N-nitrosodiphenylamine can well meet the requirements for the scorch performance of the rubber compound; the synergistic effect of each component can significantly improve the electrical conductivity, mechanical properties, processing performance and weather resistance of the conductive rubber material, with excellent comprehensive performance and long service life, thus meeting the requirements of practical applications. As shown by the test results of the examples, the volume resistivity of the conductive rubber prepared by the present invention is 760-1100 Ω·cm, the tensile strength is 21.35-22.07 MPa, the elongation at break is 502-511%, and the aging resistance is only reduced by 5-6% compared with the mixed rubber of styrene-butadiene rubber and natural rubber, indicating that the conductive rubber provided by the present invention has excellent electrical conductivity, mechanical properties, processing performance and weather resistance.

[0021] The present invention provides a preparation method of the conductive rubber described in the above technical solution, including the following steps: mixing styrene-butadiene rubber, natural rubber, carbon black, zinc oxide, composite conductive filler, stearic acid, antioxidant, environmentally friendly aromatic oil, sulfur, N,N-dicyclohexyl-2-2-benzothiazole sulfenamide and N-nitrosodiphenylamine, and performing co-extrusion to obtain the conductive rubber. The preparation method provided by the present invention is simple in operation, environmentally friendly, low in production cost, and suitable for industrial production. Specific embodiments

[0022] The present invention provides a rosin amine modified tungsten carbide, including tungsten carbide and rosin amine adsorbed on the surface of the tungsten carbide. In the present invention, the mass fraction of rosin amine in the rosin amine modified tungsten carbide is preferably 1-2%, more preferably 1-1.5%. In the present invention, the particle size of the rosin amine modified tungsten carbide is preferably 1.1-1.4 μm, more preferably 1.2-1.3 μm. In the present invention, the resistivity of the rosin amine modified tungsten carbide is preferably 17.8×10 -6 ~20.1×10 -6 Ω·cm.

[0023] The present invention provides a preparation method of the rosin amine modified tungsten carbide described in the above technical solution, including the following steps:

[0024] Mixing an aqueous solution of rosin amine with tungsten carbide, performing electrostatic adsorption treatment and then separating the solid and liquid, and drying the obtained solid component to obtain rosin amine modified tungsten carbide.

[0025] Unless otherwise specified, the raw materials used in the present invention are all commercially available products.

[0026] In the present invention, the mass ratio of rosin amine in the tungsten carbide and rosin amine aqueous solution is preferably 1:7.5 - 20, more preferably 1:10 - 20, and further preferably 1:12 - 15. In the present invention, the mass concentration of the rosin amine aqueous solution is preferably 1 - 2%, more preferably 1%. In the present invention, the particle size of the tungsten carbide is preferably 1.1 - 1.4 μm, more preferably 1.2 - 1.3 μm.

[0027] The present invention has no special limitation on the mixing, and the mixing method well-known to those skilled in the art can be adopted, such as stirring and mixing.

[0028] In the present invention, the electrostatic adsorption is preferably carried out under ultrasonic conditions. The power of the ultrasonic is preferably 120 - 1000 W, more preferably 120 - 200 W; the time of the electrostatic adsorption treatment is preferably 7 - 9 h, more preferably 7 - 8 h.

[0029] The present invention has no special limitation on the solid-liquid separation, and the solid-liquid separation method well-known to those skilled in the art can be adopted, such as suction filtration, filtration or centrifugal separation.

[0030] In the present invention, the drying temperature is preferably ≤100°C, more preferably 60 - 80°C. The present invention has no special limitation on the drying time, and it can be dried to constant weight.

[0031] The present invention provides the application of the rosin amine-modified tungsten carbide described in the above technical solution or the rosin amine-modified tungsten carbide prepared by the preparation method described in the above technical solution as a conductive filler in rubber.

[0032] The present invention provides a composite conductive filler, comprising rosin amine-modified tungsten carbide and polypyrrole; the rosin amine-modified tungsten carbide is the rosin amine-modified tungsten carbide described in the above technical solution or the rosin amine-modified tungsten carbide prepared by the preparation method described in the above technical solution. In the present invention, the mass ratio of the rosin amine-modified tungsten carbide and polypyrrole is preferably 0.5 - 2:10 - 15, more preferably 0.8 - 1.8:11 - 14, and further preferably 1 - 1.5:12 - 13. In the present invention, the particle size of the polypyrrole is preferably 100 - 500 nm, more preferably 200 - 400 nm; the resistivity of the polypyrrole is preferably 0.009 - 0.01 Ω·cm, more preferably 0.0095 - 0.01 Ω·cm, and further preferably 0.0098 - 0.01 Ω·cm.

[0033] The present invention provides the application of the composite conductive filler described in the above technical solution in rubber.

[0034] The present invention provides a conductive rubber, which comprises the following raw materials for preparation in parts by mass: 70-90 parts of styrene-butadiene rubber, 10-30 parts of natural rubber, 20-30 parts of carbon black, 3-5 parts of zinc oxide, 10.5-17 parts of the composite conductive filler as described in the above technical solution, 1-3 parts of stearic acid, 2-5 parts of antioxidant, 10-25 parts of environmental aromatic oil, 1.5-2.5 parts of sulfur, 0.5-1 part of N,N-dicyclohexyl-2-benzothiazole sulfenamide, and 0.1-0.5 part of N-nitrosodiphenylamine; the composite conductive filler is the composite conductive filler as described in the above technical solution.

[0035] In parts by mass, the raw materials for preparation of the conductive rubber provided by the present invention include 70-90 parts of styrene-butadiene rubber, preferably 75-85 parts, and more preferably 80 parts.

[0036] In parts by mass based on the mass of the styrene-butadiene rubber, the raw materials for preparation of the conductive rubber provided by the present invention include 10-30 parts of natural rubber, preferably 15-25 parts, and more preferably 20 parts.

[0037] In parts by mass based on the mass of the styrene-butadiene rubber, the raw materials for preparation of the conductive rubber provided by the present invention include 20-30 parts of carbon black, preferably 22-30 parts, and more preferably 25-30 parts. In the present invention, the carbon black preferably comprises a mixture of super abrasion furnace black N115 and super abrasion furnace black N220, and the mass ratio of super abrasion furnace black N115 to super abrasion furnace black N220 in the mixture is preferably 2:1; the particle size of the carbon black is preferably 11-19 nm, more preferably 13-17 nm, and further preferably 14-15 nm; the resistivity of the carbon black is preferably 0.5-2.5 Ω·m, more preferably 0.5-2 Ω·m, and further preferably 0.5-1 Ω·m.

[0038] In parts by mass based on the mass of the styrene-butadiene rubber, the raw materials for preparation of the conductive rubber provided by the present invention include 3-5 parts of zinc oxide, preferably 3.5-4.5 parts, and more preferably 4 parts. In the present invention, the particle size of the zinc oxide is preferably 1-100 nm, more preferably 50-100 nm.

[0039] In parts by mass based on the mass of the styrene-butadiene rubber, the raw materials for preparation of the conductive rubber provided by the present invention include 10.5-17 parts of the composite conductive filler as described in the above technical solution, preferably 11-16 parts, more preferably 12-15 parts, and further preferably 13-14 parts. In the present invention, the composite conductive filler preferably comprises 0.5-2 parts of rosin amine modified tungsten carbide and 10-15 parts of polypyrrole, the mass of the rosin amine modified tungsten carbide is more preferably 0.8-1.8 parts, and further preferably 1-1.5 parts, and the mass of the polypyrrole is more preferably 11-14 parts, and further preferably 12-13 parts.

[0040] Based on the parts by mass of the styrene-butadiene rubber, the raw materials for preparing the conductive rubber provided by the present invention include 1 to 3 parts of stearic acid, preferably 1.5 to 2.5 parts, and more preferably 2 parts.

[0041] Based on the parts by mass of the styrene-butadiene rubber, the raw materials for preparing the conductive rubber provided by the present invention include 2 to 5 parts of antioxidant, preferably 2.5 to 4.5 parts, and more preferably 3 to 4 parts. In the present invention, the antioxidant is preferably antioxidant BLE.

[0042] Based on the parts by mass of the styrene-butadiene rubber, the raw materials for preparing the conductive rubber provided by the present invention preferably include 10 to 25 parts of environmental aromatic oil, more preferably 12 to 22 parts, and even more preferably 15 to 20 parts.

[0043] Based on the parts by mass of the styrene-butadiene rubber, the raw materials for preparing the conductive rubber provided by the present invention include 1.5 to 2.5 parts of sulfur, preferably 1.8 to 2.5 parts, and more preferably 2 to 2.5 parts.

[0044] Based on the parts by mass of the styrene-butadiene rubber, the raw materials for preparing the conductive rubber provided by the present invention include 0.5 to 1 part of N,N-dicyclohexyl-2-benzothiazole sulfenamide, preferably 0.6 to 1 part, and more preferably 0.8 to 1 part.

[0045] Based on the parts by mass of the styrene-butadiene rubber, the raw materials for preparing the conductive rubber provided by the present invention include 0.1 to 0.5 part of N-nitrosodiphenylamine, preferably 0.2 to 0.4 part, and more preferably 0.2 to 0.3 part.

[0046] The present invention provides a method for preparing the conductive rubber according to the above technical solution, comprising the following steps:

[0047] Mix styrene-butadiene rubber, natural rubber, carbon black, zinc oxide, composite conductive filler, stearic acid, antioxidant, environmental aromatic oil, sulfur, N,N-dicyclohexyl-2-benzothiazole sulfenamide and N-nitrosodiphenylamine, and carry out co-blending extrusion to obtain the conductive rubber.

[0048] The present invention has no special limitation on the mixing, and the mixing methods well-known to those skilled in the art can be adopted, such as stirring and mixing.

[0049] The present invention has no special limitation on the process conditions of the co-blending extrusion, and the co-blending extrusion can be carried out by using a twin-screw extruder well-known to those skilled in the art.

[0050] The technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0051] The parameters of each raw material used in the following examples and comparative examples are as follows: the particle size of tungsten carbide powder is 1.2 - 1.3 μm; the resistivity of polypyrrole is 0.0098 Ω·cm, and the particle size is 200 nm; the resistivity of carbon black is 0.5 - 2.5 Ω·m, and the particle size is 15 nm; the particle size of zinc oxide is 50 nm; the carbon black is a mixture of super abrasion furnace black N115 and super abrasion furnace black N220 with a mass ratio of 2:1.

[0052] Example 1

[0053] Preparation of rosin amine modified tungsten carbide: Place tungsten carbide powder in an aqueous solution of rosin amine with a mass concentration of 1% and mix evenly. Carry out electrostatic adsorption treatment for 8 h under the conditions of 120 W and room temperature ultrasonic, then filter by suction. Dry the obtained solid component at 70 °C until constant weight to obtain rosin amine modified tungsten carbide; wherein, the mass ratio of tungsten carbide powder to rosin amine is 1:20.

[0054] By mass, the raw materials for preparing conductive rubber are: 70 parts of styrene-butadiene rubber, 30 parts of natural rubber, 30 parts of carbon black, 3 parts of zinc oxide, 10.5 parts of composite conductive filler (0.5 part of rosin amine modified tungsten carbide, 10 parts of polypyrrole), 2 parts of stearic acid, 3 parts of antioxidant BLE, 10 parts of environmental aromatic oil, 2.5 parts of sulfur, 1 part of N,N-dicyclohexyl-2-2-benzothiazole sulfenamide, and 0.25 part of N-nitrosodiphenylamine.

[0055] Preparation of conductive rubber: Stir and mix evenly styrene-butadiene rubber, natural rubber, carbon black, zinc oxide, composite conductive filler, stearic acid, antioxidant BLE, environmental aromatic oil, sulfur, N,N-dicyclohexyl-2-2-benzothiazole sulfenamide and N-nitrosodiphenylamine. Add the obtained mixture to a twin-screw extruder for co-blending and extrusion to obtain conductive rubber.

[0056] Example 2

[0057] Preparation of rosin amine modified tungsten carbide: Place tungsten carbide powder in an aqueous solution of rosin amine with a mass concentration of 1% and mix evenly. Carry out electrostatic adsorption treatment for 8 h under the conditions of 120 W and room temperature ultrasonic, then filter by suction. Dry the obtained solid component at 70 °C until constant weight to obtain rosin amine modified tungsten carbide; wherein, the mass ratio of tungsten carbide powder to rosin amine is 1:12.

[0058] By mass fraction, the raw materials for preparing the conductive rubber are as follows: 80 parts of styrene-butadiene rubber, 20 parts of natural rubber, 30 parts of carbon black, 4 parts of zinc oxide, 13 parts of composite conductive filler (1 part of rosin amine modified tungsten carbide, 12 parts of polypyrrole), 2 parts of stearic acid, 3 parts of antioxidant BLE, 10 parts of environmentally friendly aromatic oil, 2.5 parts of sulfur, 1 part of N,N-dicyclohexyl-2-2-benzothiazole sulfenamide, and 0.25 part of N-nitrosodiphenylamine.

[0059] The preparation method of the conductive rubber is the same as that in Example 1.

[0060] Example 3

[0061] Preparation of rosin amine modified tungsten carbide: Place tungsten carbide powder in an aqueous solution of rosin amine with a mass concentration of 1%, mix evenly, perform electrostatic adsorption treatment for 8 h under ultrasonic conditions of 120 W and room temperature, filter by suction, and dry the obtained solid component at 70 °C until constant weight to obtain rosin amine modified tungsten carbide; wherein, the mass ratio of tungsten carbide powder to rosin amine is 1:7.5.

[0062] By mass fraction, the raw materials for preparing the conductive rubber are as follows: 90 parts of styrene-butadiene rubber, 10 parts of natural rubber, 30 parts of carbon black, 5 parts of zinc oxide, 17 parts of composite conductive filler (2 parts of rosin amine modified tungsten carbide, 15 parts of polypyrrole), 2 parts of stearic acid, 3 parts of antioxidant BLE, 10 parts of environmentally friendly aromatic oil, 2.5 parts of sulfur, 1 part of N,N-dicyclohexyl 2-2-benzothiazole sulfenamide, and 0.25 part of N-nitrosodiphenylamine.

[0063] The preparation method of the conductive rubber is the same as that in Example 1.

[0064] Example 4

[0065] Prepare the conductive rubber according to the method of Example 3, and the difference from Example 3 is only that: the mass fraction of the aqueous rosin amine solution is 2%.

[0066] Comparative Example 1

[0067] Prepare the conductive rubber according to the method of Example 1, and the difference from Example 1 is only that: polypyrrole is replaced by polyaniline.

[0068] Comparative Example 2

[0069] Prepare the conductive rubber according to the method of Example 1, and the difference from Example 1 is only that: polypyrrole is replaced by polythiophene.

[0070] Comparative Example 3

[0071] Prepare the conductive rubber according to the method of Example 2, and the difference from Example 2 is only that: polypyrrole is omitted.

[0072] Comparative Example 4

[0073] The electrically conductive rubber was prepared according to the method of Example 3, with the difference from Example 3 being only that rosin amine modified tungsten carbide was omitted.

[0074] Comparative Example 5

[0075] The electrically conductive rubber was prepared according to the method of Example 3, with the difference from Example 3 being only that rosin amine modified tungsten carbide was replaced with tungsten carbide.

[0076] Comparative Example 6

[0077] The electrically conductive rubber was prepared according to the method of Example 3, with the difference from Example 3 being only that rosin amine modified tungsten carbide was replaced with cetyltrimethylammonium bromide modified tungsten carbide.

[0078] Among them, the preparation method of cetyltrimethylammonium bromide modified tungsten carbide was the same as that of rosin amine aqueous solution modified tungsten carbide.

[0079] The performance test results of the electrically conductive rubbers prepared in Examples 1 to 4 and Comparative Examples 1 to 6 are shown in Table 1. Among them, the volume resistivity was measured according to the standard GB / T1692 - 2008; the tensile strength and elongation at break were tested by an electronic universal testing machine; the heat aging resistance was characterized by the change rate of the tensile strength of the electrically conductive rubber after aging at 70°C for 96 h relative to the tensile strength of the unaged electrically conductive rubber, and the test standard was referred to GB - T3512 - 2001.

[0080] Table 1 Performance test results of the electrically conductive rubbers prepared in Examples and Comparative Examples

[0081] Project Volume Resistivity (Ω·cm) Tensile Strength (MPa) Elongation at Break (%) Aging Resistance Performance (%) Example 1 1100 21.61 511 -5 Comparative Example 1 5300 21.35 502 -6 Comparative Example 2 2700 22.07 508 -5 Example 2 920 25.44 485 -6 Comparative Example 3 3800 22.58 449 -6 Example 3 760 28.72 472 -7 Comparative Example 4 8200 20.06 483 -6 Comparative Example 5 940 25.54 447 -7 Comparative Example 6 870 25.96 456 -8 Example 4 930 26.30 432 -7

[0082] As can be seen from Table 1, the volume resistivity of the electrically conductive rubber prepared by the present invention is 760 - 1100 Ω·cm, the tensile strength is 21.35 - 22.07 MPa, the elongation at break is 502 - 511%, and the aging resistance performance is only reduced by 5 - 6% compared with the blended rubber of styrene - butadiene rubber and natural rubber. This shows that the present invention uses rosin amine modified tungsten carbide and polypyrrole as composite conductive fillers, and in combination with other components, can improve the electrical conductivity, mechanical properties, processing properties and weather resistance of the electrically conductive rubber material, with excellent comprehensive performance and long service life, thus meeting the requirements of practical applications.

[0083] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A conductive rubber, characterized in that, The preparation raw materials include the following parts by mass: 70 - 90 parts of styrene - butadiene rubber, 10 - 30 parts of natural rubber, 20 - 30 parts of carbon black, 3 - 5 parts of zinc oxide, 10.5 - 17 parts of composite conductive filler, 1 - 3 parts of stearic acid, 2 - 5 parts of antioxidant, 10 - 25 parts of environmentally friendly aromatic oil, 1.5 - 2.5 parts of sulfur, 0.5 - 1 part of N,N - dicyclohexyl - 2 - 2 - benzothiazole sulfenamide, and 0.1 - 0.5 part of N - nitrosodiphenylamine; The composite conductive filler includes rosin amine - modified tungsten carbide and polypyrrole, and the mass ratio of rosin amine - modified tungsten carbide to polypyrrole is 0.5 - 2:10 - 15; The rosin amine - modified tungsten carbide includes tungsten carbide and rosin amine adsorbed on the surface of the tungsten carbide; The preparation method of the rosin amine - modified tungsten carbide includes the following steps: mixing an aqueous solution of rosin amine with tungsten carbide, performing electrostatic adsorption treatment and then solid - liquid separation, and drying the obtained solid component to obtain rosin amine - modified tungsten carbide.

2. The electrically conductive rubber according to claim 1, characterized in that, The mass ratio of tungsten carbide to rosin amine in the aqueous solution of rosin amine is 1:7.5 - 20.

3. The electrically conductive rubber according to claim 1 or 2, characterized in that, The electrostatic adsorption is carried out under ultrasonic conditions, the power of the ultrasonic is 120 - 1000W, and the time is 7 - 9h.

4. The preparation method of the conductive rubber according to any one of claims 1 to 3, characterized in that, It includes the following steps: Mix styrene - butadiene rubber, natural rubber, carbon black, zinc oxide, composite conductive filler, stearic acid, antioxidant, environmentally friendly aromatic oil, sulfur, N,N - dicyclohexyl - 2 - 2 - benzothiazole sulfenamide and N - nitrosodiphenylamine, and perform co - extrusion to obtain conductive rubber.