High-performance COPNA resin-based electric brush composite material and preparation method thereof

Abstract

The invention discloses a high-performance COPNA resin-based electric brush composite material and a preparation method thereof.The preparation method comprises the steps that catalytic cracking oil slurry is weighed and placed in a reactor, a cross-linking agent and a catalyst are added, the reactor is fixed in an oil bath, heating and stirring reaction are carried out, water drops are generated in the reaction process, the viscosity of resin is increased, and the high-performance COPNA resin-based electric brush composite material is obtained. When the viscosity of the resin is increased and a wire winding phenomenon occurs approximately, stopping the reaction, cooling, and taking out a product to obtain COPNA resin; the preparation method comprises the following steps: respectively crushing, drying and sieving COPNA resin and graphite, completely dissolving the COPNA resin in a trichloromethane solution, then adding the graphite, heating and stirring to obtain uniformly mixed electric brush aggregate; drying and sieving to obtain dry electric brush aggregate powder; performing hot press molding on the electric brush aggregate powder to obtain an electric brush blank; and roasting the electric brush blank to obtain the high-performance COPNA resin-based electric brush. The COPNA resin-based electric brush composite material obtained by the preparation method disclosed by the invention has low resistivity, high strength modulus and good conductivity.

Description

Technical Field

[0001] The invention relates to the field of electric tool accessories, and in particular to a high-performance COPNA resin-based brush composite material and a preparation method thereof. Background Art

[0002] With the advancement of technology and the increasing requirements for environmental protection, the global demand for new materials continues to increase, especially the demand for carbon materials is rapidly expanding. Mesophase pitch, mesophase carbon microspheres, COPNA resin, pitch-based carbon fiber, foamed carbon, C / C composite materials, etc. have shown broad application prospects.

[0003] Since Otani et al. synthesized condensed polynuclear aromatics (COPNA) resin using pyrene and phenanthrene as monomers, p-phenylenediol as a crosslinker, and p-toluenesulfonic acid as a catalyst, it has attracted widespread attention from scholars at home and abroad. After years of development, the synthetic raw materials of COPNA resin have gradually expanded from the initial aromatic compounds to relatively cheap aromatic derivatives, such as coal tar, FCC oil slurry, heavy residual oil, and petroleum asphalt, etc. The obtained COPNA resin has good adhesion, impregnation and heat resistance. COPNA resin, also known as asphalt resin, is a thermosetting polymer resin with a condensed polycyclic structure as the main body. COPNA resin has excellent high temperature resistance, corrosion resistance, high compressive strength, good formability and special electromagnetic properties, and has good affinity with carbon materials, becoming a hot topic in carbon material research. COPNA resin can be used as a precursor for the preparation of a variety of carbon materials, and is also widely used in carbon / carbon composite material molding, brake wear-resistant materials and high heat-resistant fibers.

[0004] Currently disclosed methods include the preparation of asphalt resin using heavy residue oil extract as raw material, and the obtained resin has better heat resistance at 800°C than polyimide. Methods for preparing condensed polycyclic polynuclear aromatic resin using petroleum residue oil or coal tar as raw material, and the prepared resin has the characteristics of good heat resistance and high strength. Methods for preparing polycyclic polynuclear aromatic resin using biomass raw materials (bamboo tar), and the obtained resin has the characteristics of good heat resistance and high carbon residue rate. Methods for synthesizing polycyclic polynuclear aromatic resin using catalytic cracking heavy oil, and the obtained resin has good heat resistance, and the 10% thermal weight loss temperature is above 380°C.

[0005] Brushes are mostly installed on the commutator or collector ring of the motor. As the sliding contact body for conducting or importing current, they have the characteristics of smoothness, wear resistance, good conductivity, etc. Among them, COPNA resin has excellent affinity with carbon materials and is very suitable for use as a binder for brushes. As early as the 1990s, Japan's Sumitomo Company used similar resins in the production of brushes. The brushes produced have the advantages of low friction coefficient and high thermal weight loss temperature.

[0006] With the development of science and technology, the types of motors and the working conditions of their use are becoming more and more diverse, so various grades of brushes are needed to meet these requirements. Therefore, the types of brushes are also increasing with the development of the motor industry. Brushes are widely used in various AC and DC generators, synchronous motors, battery DC motors, crane motor collector rings, various types of welding machines, etc. The existing brushes have poor performance, poor stability, and high resistance, which leads to increased wear of motor brushes; especially poor wear resistance, poor conductivity, insufficient heat resistance, and too low hardness, which cannot meet the various requirements of high-performance motors for brushes.

[0007] Patent CN201510038870.2 discloses a method for preparing graphite brushes using molybdate-modified asphalt resin as a binder. Using molybdate-modified asphalt resin and graphite as raw materials, a molybdate-modified asphalt resin / graphite composite brush is prepared by wet mixing through raw material pretreatment, hydraulic molding, and roasting. The brushes prepared by the wet mixing process of molybdate-modified asphalt resin and graphite dissolved in chloroform are significantly better than Morgan brushes sold on the market in all aspects.

[0008] Patent CN1414028A discloses an aromatic hydrocarbon resin-based friction material. A friction material base is prepared by using COPNA resin, carbon-based composite fiber, filler and friction performance modifier, and then pressed together with a friction material float to prepare a friction material for manufacturing brake pads. This friction material has high cohesive strength, high thermal decomposition temperature, good toughness and high bonding strength, which improves the comprehensive performance of traditional friction materials, but its production process is complicated.

[0009] Patent CN109627762A discloses a nano conductive powder for wear-resistant brushes and a preparation method thereof. Based on cyanate ester and polyimide, combined with epoxy resin, through the selection and compatibility of the resin matrix, combined with the preparation process, extrusion granulation and then molding, the brush has excellent wear resistance and heat resistance, and also has good electrical properties. However, the brush preparation process of this method is relatively complicated, and more raw materials are added during preparation.

[0010] Patent CN102324681A discloses a method for producing a conductive anti-friction material for brushes. COPNA resin, graphite powder and artificial synthetic graphite are used as raw materials, mixed evenly, kneaded, ground and screened, pressed, sintered for about 140 hours, and finally finely ground. This invention method ensures that every contact point between aggregates is effectively connected, ensures the uniformity after pressing and the consistency of various technical parameters of the product, and the preparation process is simple, but the staged lifting and heat preservation method used in sintering makes the preparation time too long. Summary of the invention

[0011] The purpose of the present invention is to provide a high-performance COPNA resin-based brush composite material and a preparation method thereof, which belongs to the technical field of resin-based brushes. The present invention uses COPNA resin as a binder in the brush field to create a high-performance polymer material obtained with low-cost raw materials, and the prepared brush has excellent compressive strength, flexural strength and good electrical conductivity, and the process is simple, the quality is stable, and it is suitable for industrial production.

[0012] In order to achieve the above-mentioned object of the invention, the present invention provides a method for preparing a high-performance COPNA resin-based brush composite material, which comprises the following steps:

[0013] S1: Weigh the catalytic cracking oil slurry into the reactor, add the crosslinking agent and the catalyst, fix the reactor in the oil bath, heat and stir, and introduce N2. When heated to the reaction temperature, the reaction occurs. During the reaction, water droplets will be generated and the viscosity of the resin will increase. When the viscosity of the resin increases to cause tangling, stop the reaction, cool, and take out the product to obtain COPNA resin;

[0014] S2: COPNA resin and graphite are crushed, dried and sieved respectively, COPNA resin is completely dissolved in chloroform solution, and then graphite is added, heated and stirred to obtain a uniformly mixed brush aggregate;

[0015] S3: The uniformly mixed brush aggregate is evaporated to dryness under stirring in an oil bath, and then further dried in an oven, and then fully crushed using a ball mill, and then sieved to obtain dry brush aggregate powder;

[0016] S4: placing brush aggregate powder into a mold and performing hot pressing to obtain a brush blank;

[0017] S5: calcining the brush blank in a N2 atmosphere to obtain a high-performance COPNA resin-based brush.

[0018] Furthermore, the mass ratio of the COPNA resin to graphite is 10-30:70-90, for example but not limited to 30:70, 20:80, 15:85, 10:90, preferably 15:85.

[0019] Furthermore, the carbon residue rate of the COPNA resin is 30%-50%, and the β resin content is 15%-50%.

[0020] Furthermore, the catalytic cracking slurry is Ningxia slurry or Daqing slurry with high aromatic content, preferably Daqing slurry, whose average molecular formula is C 31.82 H 27.03 .

[0021] Furthermore, the cross-linking agent is at least one of trioxymethylene, benzaldehyde, terephthalic acid alcohol, benzaldehyde, terephthaloyl chloride, terephthalic acid aldehyde and divinylbenzene, preferably terephthalic acid alcohol.

[0022] Furthermore, the catalyst is at least one of an inorganic strong acid and an organic strong acid; the inorganic strong acid is at least one of sulfuric acid and hydrochloric acid; the organic strong acid is toluenesulfonic acid, preferably p-toluenesulfonic acid.

[0023] Furthermore, based on 100wt% of the added amount of the catalytic cracking oil slurry, the added amount of the cross-linking agent is 20wt%-60wt%, and the added amount of the catalyst is 5wt%-15wt%.

[0024] Furthermore, the graphite is at least one of colloidal graphite, flake graphite and nanographite, preferably nanographite.

[0025] Preferably, in step S1, the flow rate of N2 is 40-50 mL / min.

[0026] Preferably, in step S1, the reaction temperature is 120-160°C.

[0027] Preferably, in step S2, the mixing temperature is 60-80°C, and the mixing time is 10-60 min.

[0028] Preferably, in step S3, the temperature of evaporation under oil bath stirring is 60-100° C., and the time of evaporation is 60-240 min.

[0029] Preferably, in step S3, the oven drying temperature is 80-150° C., and the drying time is 50-100 min.

[0030] Preferably, in step S3, the brush aggregate is ball-milled and sieved into 100-300 meshes.

[0031] Preferably, in step S4, during the hot pressing process, the density of the formed brush is 1.4-2.2 g / cm 3 .

[0032] Preferably, in step S4, during the hot pressing process, the hot pressing temperature is 150-200° C., the pressure is 10-50 MPa, and the time is 30-80 min.

[0033] Preferably, in step S5, the calcination temperature is 200-500°C, the N2 flow rate is 50-100 ml / min, the heating rate is 0.20-2.0°C / min, and the calcination time is 2-40h.

[0034] The present invention also provides a resin brush obtained by the above-mentioned preparation method.

[0035] The preparation method of the present invention uses catalytic cracking oil slurry and a cross-linking agent to cross-link under the action of a catalyst to obtain a COPNA resin, uses a low-temperature catalytic synthesis strategy to develop a COPNA resin with excellent heat resistance and adhesion as a binder, and combines graphite powder with the COPNA resin. Through the selection and compatibility of the resin matrix and combined with a reasonable preparation process, the prepared COPNA resin-based brush composite material has low resistivity and high strength modulus, excellent compressive strength, flexural strength and good electrical conductivity, as well as excellent wear resistance and heat resistance, which is better than the best British Morgan IM824 brush in the world, lays a theoretical and technical foundation for the preparation of electric carbon materials such as high-end brushes, and can be used for high-quality and high-requirement motors and engines. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 The invention discloses a high-performance COPNA resin-based brush. DETAILED DESCRIPTION

[0037] The following is a detailed description of an embodiment of the present invention: This embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation method and process are given, but the protection scope of the present invention is not limited to the following embodiment.

[0038] Example 1

[0039] Weigh the catalytic cracking oil slurry Daqing oil slurry into the reactor, and add terephthalic acid and toluenesulfonic acid. The mass ratio of catalytic cracking oil slurry, terephthalic acid and toluenesulfonic acid is 10:3:0.75. Fix the reactor in an oil bath, heat and stir, and introduce N2 at a flow rate of 50mL / min. Heat to the reaction temperature of 140℃ and keep the temperature constant. Water droplets will be generated during the reaction and the viscosity of the resin will increase. When the viscosity of the resin increases and the entanglement phenomenon occurs, stop the reaction. After cooling to room temperature, take out the product to obtain COPNA resin. The residual carbon rate of the obtained COPNA resin is 40.99%, and the β resin content is 29.10%.

[0040] COPNA resin and colloidal graphite are crushed, dried and sieved to 200 meshes respectively, and COPNA resin is completely dissolved in chloroform solution, and then colloidal graphite is added, heated and stirred to obtain a uniformly mixed brush aggregate. The mass ratio of COPNA resin and colloidal graphite is 15% COPNA resin and 85% colloidal graphite.

[0041] The mixed brush aggregate is evaporated to dryness under stirring in an oil bath, and then further dried in an oven. Then, it is fully crushed using a ball mill and sieved to obtain dry brush aggregate powder. The brush aggregate powder is placed in a brush mold and pressed at 200℃ and 10MPa for 30 minutes and maintained at a pressure of 50 minutes to obtain a brush blank. During the hot pressing process, the density of the molded brush is 1.64g / cm 3 The brush blank was placed in a tubular furnace for calcination, nitrogen was introduced at a nitrogen flow rate of 60 ml / min, the temperature was raised to 300°C at a rate of 0.25°C / min, and the calcination time was 2 hours. After calcination and molding, a high-performance COPNA resin-based brush composite material according to the embodiment of the present invention was obtained.

[0042] The obtained brush had a flexural strength of 27.56 MPa, a compressive strength of 40.86 MPa, and a resistivity of 260 μΩ·m.

[0043] Example 2

[0044] Weigh the catalytic cracking oil slurry Daqing oil slurry into the reactor, and add trioxane and p-toluenesulfonic acid. The mass ratio of catalytic cracking oil slurry, trioxane and p-toluenesulfonic acid is 10:2:0.5. Fix the reactor in an oil bath, heat and stir, and introduce N2 at a flow rate of 50mL / min. Heat to the reaction temperature of 140℃ and keep the temperature constant. Water droplets will be generated during the reaction and the viscosity of the resin will increase. When the viscosity of the resin increases and the entanglement phenomenon occurs, stop the reaction. After cooling to room temperature, take out the product to obtain COPNA resin. The residual carbon rate of the obtained COPNA resin is 30.72%, and the β resin content is 15.63%.

[0045] COPNA resin and colloidal graphite are crushed, dried and sieved to 200 meshes respectively, and COPNA resin is completely dissolved in chloroform solution, and then colloidal graphite is added, heated and stirred to obtain a uniformly mixed brush aggregate. The mass ratio of COPNA resin and colloidal graphite is 15% COPNA resin and 85% colloidal graphite.

[0046] The uniformly mixed brush aggregate is evaporated to dryness under stirring in an oil bath, and then further dried in an oven. Then, the mixed brush aggregate is fully crushed by a ball mill, and then sieved to obtain dry brush aggregate powder.

[0047] The evenly mixed brush aggregate is evaporated to dryness under stirring in an oil bath, and then further dried in an oven. Then, it is fully crushed using a ball mill, and sieved to obtain a dry brush aggregate powder. The brush aggregate powder is placed in a brush mold, and pressed for 30 minutes at 200°C and 50MPa, and the pressure is maintained for 50 minutes to obtain a brush blank. During the hot pressing process, the density of the molded brush is 1.64g / cm3. The brush blank is placed in a tubular furnace for roasting, and nitrogen is introduced at a nitrogen flow rate of 50ml / min. The temperature is raised to 400°C at 0.25°C / min for roasting, and the roasting time is 2h. After roasting and molding, the high-performance COPNA resin-based brush composite material of the embodiment of the present invention is obtained.

[0048] The obtained brush had a flexural strength of 15.59 MPa, a compressive strength of 27.74 MPa, and a resistivity of 242 μΩ·m.

[0049] Example 3

[0050] Weigh catalytic cracking oil slurry Daqing oil slurry into the reactor, and add benzaldehyde and sulfuric acid. The mass ratio of catalytic cracking oil slurry, benzaldehyde and sulfuric acid is 10:4:1. Fix the reactor in an oil bath, heat and stir, and introduce N2 at a flow rate of 50mL / min. Heat to the reaction temperature of 140°C and keep the temperature constant. Water droplets will be generated during the reaction and the viscosity of the resin will increase. When the viscosity of the resin increases and the entanglement phenomenon occurs, stop the reaction. After cooling to room temperature, take out the product to obtain COPNA resin. The residual carbon rate of the obtained COPNA resin is 45.98%, and the β resin content is 25.73%.

[0051] COPNA resin and colloidal graphite are crushed, dried and sieved to 200 meshes respectively, and COPNA resin is completely dissolved in chloroform solution, and then colloidal graphite is added, heated and stirred to obtain a uniformly mixed brush aggregate. The mass ratio of COPNA resin and colloidal graphite is 15% COPNA resin and 85% colloidal graphite.

[0052] The uniformly mixed brush aggregate is evaporated to dryness under stirring in an oil bath, and then further dried in an oven, and then fully crushed using a ball mill, and sieved to obtain a dry brush aggregate powder. The brush aggregate powder is placed in a brush mold, pressed at 200°C and 30MPa for 30 minutes and maintained at pressure for 50 minutes to obtain a brush blank. During the hot pressing process, the density of the molded brush is 1.64g / cm3. The brush blank is placed in a tubular furnace for roasting, nitrogen is introduced, and the nitrogen flow rate is 100ml / min. The temperature is raised to 200°C at 0.25°C / min for roasting, and the roasting time is 2h. After roasting and molding, the high-performance COPNA resin-based brush composite material of the embodiment of the present invention is obtained.

[0053] The obtained brush had a flexural strength of 8.20 MPa, a compressive strength of 16.53 MPa, and a resistivity of 265 μΩ·m.

[0054] Example 4

[0055] Weigh catalytic cracking oil slurry Daqing oil slurry into the reactor, and add terephthalaldehyde and hydrochloric acid. The mass ratio of catalytic cracking oil slurry, terephthalaldehyde and hydrochloric acid is 10:6:1.5. Fix the reactor in an oil bath, heat and stir, and introduce N2 at a flow rate of 50mL / min. Heat to the reaction temperature of 140°C and keep the temperature constant. Water droplets will be generated during the reaction and the viscosity of the resin will increase. When the viscosity of the resin increases and entanglement occurs, stop the reaction. After cooling to room temperature, take out the product to obtain COPNA resin. The residual carbon rate of the obtained COPNA resin is 48.55%, and the β resin content is 24.81%.

[0056] COPNA resin and colloidal graphite are crushed, dried and sieved to 200 meshes respectively, and COPNA resin is completely dissolved in chloroform solution, and then colloidal graphite is added, heated and stirred to obtain a uniformly mixed brush aggregate. The mass ratio of COPNA resin and colloidal graphite is 15% COPNA resin and 85% colloidal graphite.

[0057] The evenly mixed brush aggregate is evaporated to dryness under stirring in an oil bath, and then further dried in an oven. Then, it is fully crushed using a ball mill, and sieved to obtain a dry brush aggregate powder. The brush aggregate powder is placed in a brush mold, and pressed at 200°C and 20MPa for 30 minutes and maintained at pressure for 50 minutes to obtain a brush blank. During the hot pressing process, the density of the molded brush is 1.64g / cm3. The brush blank is placed in a tubular furnace for roasting, and nitrogen is introduced at a nitrogen flow rate of 80ml / min. The temperature is raised to 500°C at 0.25°C / min for roasting, and the roasting time is 2h. After roasting and molding, the high-performance COPNA resin-based brush composite material of the embodiment of the present invention is obtained.

[0058] The obtained brush had a flexural strength of 10.08 MPa, a compressive strength of 22.41 MPa, and a resistivity of 323 μΩ·m.

[0059] Example 5

[0060] Weigh the catalytic cracking oil slurry Daqing oil slurry into the reactor, and add terephthalic acid and toluenesulfonic acid. The mass ratio of catalytic cracking oil slurry, terephthalic acid and toluenesulfonic acid is 10:3:0.75. Fix the reactor in an oil bath, heat and stir, and introduce N2 at a flow rate of 50mL / min. Heat to the reaction temperature of 140℃ and keep the temperature constant. Water droplets will be generated during the reaction and the viscosity of the resin will increase. When the viscosity of the resin increases and the entanglement phenomenon occurs, stop the reaction. After cooling to room temperature, take out the product to obtain COPNA resin. The residual carbon rate of the obtained COPNA resin is 40.99%, and the β resin content is 29.10%.

[0061] COPNA resin and colloidal graphite are crushed, dried and sieved to 200 meshes respectively, and COPNA resin is completely dissolved in chloroform solution, and then colloidal graphite is added, heated and stirred to obtain a uniformly mixed brush aggregate. The mass ratio of COPNA resin and colloidal graphite is 10% COPNA resin and 90% colloidal graphite.

[0062] The mixed brush aggregate is evaporated to dryness under stirring in an oil bath, and then further dried in an oven. Then, it is fully crushed using a ball mill and sieved to obtain dry brush aggregate powder. The brush aggregate powder is placed in a brush mold and pressed at 200℃ and 10MPa for 30 minutes and maintained at a pressure of 50 minutes to obtain a brush blank. During the hot pressing process, the density of the molded brush is 1.64g / cm 3 The brush blank was placed in a tubular furnace for calcination, nitrogen was introduced at a nitrogen flow rate of 60 ml / min, the temperature was raised to 300°C at a rate of 0.25°C / min, and the calcination time was 2 hours. After calcination and molding, a high-performance COPNA resin-based brush composite material according to the embodiment of the present invention was obtained.

[0063] The obtained brush had a flexural strength of 15.55 MPa, a compressive strength of 20.01 MPa, and a resistivity of 150 μΩ·m.

[0064] Example 6

[0065] Weigh the catalytic cracking oil slurry Daqing oil slurry into the reactor, and add terephthalic acid and toluenesulfonic acid. The mass ratio of catalytic cracking oil slurry, terephthalic acid and toluenesulfonic acid is 10:3:0.75. Fix the reactor in an oil bath, heat and stir, and introduce N2 at a flow rate of 50mL / min. Heat to the reaction temperature of 140℃ and keep the temperature constant. Water droplets will be generated during the reaction and the viscosity of the resin will increase. When the viscosity of the resin increases and the entanglement phenomenon occurs, stop the reaction. After cooling to room temperature, take out the product to obtain COPNA resin. The residual carbon rate of the obtained COPNA resin is 40.99%, and the β resin content is 29.10%.

[0066] COPNA resin and colloidal graphite are crushed, dried and sieved to 200 meshes respectively, and COPNA resin is completely dissolved in chloroform solution, and then colloidal graphite is added, heated and stirred to obtain a uniformly mixed brush aggregate. The mass ratio of COPNA resin and colloidal graphite is 10% COPNA resin and 90% colloidal graphite.

[0067] The mixed brush aggregate is evaporated to dryness under stirring in an oil bath, and then further dried in an oven. Then, it is fully crushed using a ball mill and sieved to obtain dry brush aggregate powder. The brush aggregate powder is placed in a brush mold and pressed at 150℃ and 10MPa for 30 minutes and maintained at a pressure of 50 minutes to obtain a brush blank. During the hot pressing process, the density of the molded brush is 1.64g / cm 3 The brush blank was placed in a tubular furnace for calcination, nitrogen was introduced at a nitrogen flow rate of 60 ml / min, the temperature was raised to 400°C at a rate of 0.25°C / min, and the calcination time was 10 hours. After calcination and molding, a high-performance COPNA resin-based brush composite material according to the embodiment of the present invention was obtained.

[0068] The obtained brush had a flexural strength of 18.42 MPa, a compressive strength of 15.55 MPa, and a resistivity of 143 μΩ·m.

[0069] Example 7

[0070] Weigh the catalytic cracking oil slurry Daqing oil slurry into the reactor, and add terephthalic acid and toluenesulfonic acid. The mass ratio of catalytic cracking oil slurry, terephthalic acid and toluenesulfonic acid is 10:3:0.75. Fix the reactor in an oil bath, heat and stir, and introduce N2 at a flow rate of 50mL / min. Heat to the reaction temperature of 140℃ and keep the temperature constant. Water droplets will be generated during the reaction and the viscosity of the resin will increase. When the viscosity of the resin increases and the entanglement phenomenon occurs, stop the reaction. After cooling to room temperature, take out the product to obtain COPNA resin. The residual carbon rate of the obtained COPNA resin is 40.99%, and the β resin content is 29.10%.

[0071] COPNA resin and colloidal graphite are crushed, dried and sieved to 200 meshes respectively, and COPNA resin is completely dissolved in chloroform solution, and then colloidal graphite is added, heated and stirred to obtain a uniformly mixed brush aggregate. The mass ratio of COPNA resin and colloidal graphite is 10% COPNA resin and 90% colloidal graphite.

[0072] The mixed brush aggregate is evaporated to dryness under oil bath stirring, and then dried in an oven. Then, it is fully crushed by ball mill and sieved to obtain dry brush aggregate powder. The brush aggregate powder is placed in a brush mold and pressed at 160℃ and 10MPa for 30min and maintained at a pressure of 50min to obtain a brush blank. During the hot pressing process, the density of the molded brush is 1.64g / cm 3 The brush blank was placed in a tubular furnace for calcination, nitrogen was introduced at a nitrogen flow rate of 60 ml / min, the temperature was raised to 200°C at a rate of 0.25°C / min, and the calcination time was 4 hours. After calcination and molding, a high-performance COPNA resin-based brush composite material according to the embodiment of the present invention was obtained.

[0073] The obtained brush had a flexural strength of 9.86 MPa, a compressive strength of 10.70 MPa, and a resistivity of 150 μΩ·m.

[0074] Example 8

[0075] Weigh the catalytic cracking oil slurry Daqing oil slurry into the reactor, and add terephthalic acid and toluenesulfonic acid. The mass ratio of catalytic cracking oil slurry, terephthalic acid and toluenesulfonic acid is 10:3:0.75. Fix the reactor in an oil bath, heat and stir, and introduce N2 at a flow rate of 50mL / min. Heat to the reaction temperature of 140℃ and keep the temperature constant. Water droplets will be generated during the reaction and the viscosity of the resin will increase. When the viscosity of the resin increases and the entanglement phenomenon occurs, stop the reaction. After cooling to room temperature, take out the product to obtain COPNA resin. The residual carbon rate of the obtained COPNA resin is 40.99%, and the β resin content is 29.10%.

[0076] COPNA resin and colloidal graphite are crushed, dried and sieved to 200 meshes respectively, and COPNA resin is completely dissolved in chloroform solution, and then colloidal graphite is added, heated and stirred to obtain a uniformly mixed brush aggregate. The mass ratio of COPNA resin and colloidal graphite is 10% COPNA resin and 90% colloidal graphite.

[0077] The mixed brush aggregate is evaporated to dryness under oil bath stirring, and then dried in an oven. Then, it is fully crushed by ball mill and sieved to obtain dry brush aggregate powder. The brush aggregate powder is placed in a brush mold and pressed at 180℃ and 10MPa for 30min and maintained at a pressure of 50min to obtain a brush blank. During the hot pressing process, the density of the molded brush is 1.64g / cm 3 The brush blank was placed in a tubular furnace for calcination, nitrogen was introduced at a nitrogen flow rate of 60 ml / min, the temperature was raised to 500°C at a rate of 0.25°C / min, and the calcination time was 8 hours. After calcination and molding, a high-performance COPNA resin-based brush composite material according to the embodiment of the present invention was obtained.

[0078] The obtained brush had a flexural strength of 14.27 MPa, a compressive strength of 24.76 MPa, and a resistivity of 269 μΩ·m.

[0079] Example 9

[0080] Weigh the catalytic cracking oil slurry Daqing oil slurry into the reactor, and add terephthalic acid and toluenesulfonic acid. The mass ratio of catalytic cracking oil slurry, terephthalic acid and toluenesulfonic acid is 10:3:0.75. Fix the reactor in an oil bath, heat and stir, and introduce N2 at a flow rate of 50mL / min. Heat to the reaction temperature of 140℃ and keep the temperature constant. Water droplets will be generated during the reaction and the viscosity of the resin will increase. When the viscosity of the resin increases and the entanglement phenomenon occurs, stop the reaction. After cooling to room temperature, take out the product to obtain COPNA resin. The residual carbon rate of the obtained COPNA resin is 40.99%, and the β resin content is 29.10%.

[0081] COPNA resin and colloidal graphite are crushed, dried and sieved to 200 meshes respectively, and COPNA resin is completely dissolved in chloroform solution, and then colloidal graphite is added, heated and stirred to obtain a uniformly mixed brush aggregate. The mass ratio of COPNA resin and colloidal graphite is 20% COPNA resin and 80% colloidal graphite.

[0082] The mixed brush aggregate is evaporated to dryness under stirring in an oil bath, and then further dried in an oven. Then, it is fully crushed using a ball mill and sieved to obtain dry brush aggregate powder. The brush aggregate powder is placed in a brush mold and pressed at 200℃ and 10MPa for 30 minutes and maintained at a pressure of 50 minutes to obtain a brush blank. During the hot pressing process, the density of the molded brush is 1.64g / cm 3 The brush blank was placed in a tubular furnace for calcination, nitrogen was introduced at a nitrogen flow rate of 60 ml / min, the temperature was raised to 300°C at a rate of 0.25°C / min, and the calcination time was 2 hours. After calcination and molding, a high-performance COPNA resin-based brush composite material according to the embodiment of the present invention was obtained.

[0083] The obtained brush had a flexural strength of 24.36 MPa, a compressive strength of 29.04 MPa, and a resistivity of 514 μΩ·m.

[0084] Example 10

[0085] Weigh the catalytic cracking oil slurry Daqing oil slurry into the reactor, and add terephthalic acid and toluenesulfonic acid. The mass ratio of catalytic cracking oil slurry, terephthalic acid and toluenesulfonic acid is 10:3:0.75. Fix the reactor in an oil bath, heat and stir, and introduce N2 at a flow rate of 50mL / min. Heat to the reaction temperature of 140℃ and keep the temperature constant. Water droplets will be generated during the reaction and the viscosity of the resin will increase. When the viscosity of the resin increases and the entanglement phenomenon occurs, stop the reaction. After cooling to room temperature, take out the product to obtain COPNA resin. The residual carbon rate of the obtained COPNA resin is 40.99%, and the β resin content is 29.10%.

[0086] COPNA resin and colloidal graphite are crushed, dried and sieved to 200 meshes respectively, and COPNA resin is completely dissolved in chloroform solution, and then colloidal graphite is added, heated and stirred to obtain a uniformly mixed brush aggregate. The mass ratio of COPNA resin and colloidal graphite is 20% COPNA resin and 80% colloidal graphite.

[0087] The mixed brush aggregate is evaporated to dryness under stirring in an oil bath, and then further dried in an oven. Then, it is fully crushed using a ball mill and sieved to obtain dry brush aggregate powder. The brush aggregate powder is placed in a brush mold and pressed at 200℃ and 10MPa for 30 minutes and maintained at a pressure of 50 minutes to obtain a brush blank. During the hot pressing process, the density of the molded brush is 1.64g / cm 3 The brush blank was placed in a tubular furnace for calcination, nitrogen was introduced at a nitrogen flow rate of 60 ml / min, the temperature was raised to 400°C at 2.0°C / min, and the calcination time was 2 hours. After calcination and molding, a high-performance COPNA resin-based brush composite material according to the embodiment of the present invention was obtained.

[0088] The obtained brush had a flexural strength of 14.11 MPa, a compressive strength of 18.09 MPa, and a resistivity of 430 μΩ·m.

[0089] Embodiment 11

[0090] Weigh the catalytic cracking oil slurry Daqing oil slurry into the reactor, and add terephthalic acid and toluenesulfonic acid. The mass ratio of catalytic cracking oil slurry, terephthalic acid and toluenesulfonic acid is 10:3:0.75. Fix the reactor in an oil bath, heat and stir, and introduce N2 at a flow rate of 50mL / min. Heat to the reaction temperature of 140℃ and keep the temperature constant. Water droplets will be generated during the reaction and the viscosity of the resin will increase. When the viscosity of the resin increases and the entanglement phenomenon occurs, stop the reaction. After cooling to room temperature, take out the product to obtain COPNA resin. The residual carbon rate of the obtained COPNA resin is 40.99%, and the β resin content is 29.10%.

[0091] COPNA resin and colloidal graphite are crushed, dried and sieved to 200 meshes respectively, and COPNA resin is completely dissolved in chloroform solution, and then colloidal graphite is added, heated and stirred to obtain a uniformly mixed brush aggregate. The mass ratio of COPNA resin and colloidal graphite is 20% COPNA resin and 80% colloidal graphite.

[0092] The mixed brush aggregate is evaporated to dryness under stirring in an oil bath, and then further dried in an oven. Then, it is fully crushed using a ball mill and sieved to obtain dry brush aggregate powder. The brush aggregate powder is placed in a brush mold and pressed at 200℃ and 10MPa for 30 minutes and maintained at a pressure of 50 minutes to obtain a brush blank. During the hot pressing process, the density of the molded brush is 1.64g / cm 3 The brush blank was placed in a tubular furnace for calcination, nitrogen was introduced at a nitrogen flow rate of 60 ml / min, the temperature was raised to 200°C at a rate of 1.0°C / min, and the calcination time was 2 hours. After calcination and molding, a high-performance COPNA resin-based brush composite material according to the embodiment of the present invention was obtained.

[0093] The obtained brush had a flexural strength of 6.97 MPa, a compressive strength of 8.69 MPa, and a resistivity of 347 μΩ·m.

[0094] Example 12

[0095] Weigh the catalytic cracking oil slurry Daqing oil slurry into the reactor, and add terephthalic acid and toluenesulfonic acid. The mass ratio of catalytic cracking oil slurry, terephthalic acid and toluenesulfonic acid is 10:3:0.75. Fix the reactor in an oil bath, heat and stir, and introduce N2 at a flow rate of 50mL / min. Heat to the reaction temperature of 140℃ and keep the temperature constant. Water droplets will be generated during the reaction and the viscosity of the resin will increase. When the viscosity of the resin increases and the entanglement phenomenon occurs, stop the reaction. After cooling to room temperature, take out the product to obtain COPNA resin. The residual carbon rate of the obtained COPNA resin is 40.99%, and the β resin content is 29.10%.

[0096] COPNA resin and flake graphite are crushed, dried and sieved to 200 meshes respectively, COPNA resin is completely dissolved in chloroform solution, and then flake graphite is added, heated and stirred to obtain a uniformly mixed brush aggregate. The mass ratio of COPNA resin and flake graphite is 20% COPNA resin and 80% flake graphite.

[0097] The mixed brush aggregate is evaporated to dryness under stirring in an oil bath, and then further dried in an oven. Then, it is fully crushed using a ball mill and sieved to obtain dry brush aggregate powder. The brush aggregate powder is placed in a brush mold, and pressed at 200℃ and 10MPa for 30 minutes and maintained at a pressure of 50 minutes to obtain a brush blank. During the hot pressing process, the density of the molded brush is 1.72g / cm 3 The brush blank was placed in a tubular furnace for calcination, nitrogen was introduced at a nitrogen flow rate of 60 ml / min, the temperature was raised to 500°C at a rate of 0.20°C / min, and the calcination time was 2 hours. After calcination and molding, a high-performance COPNA resin-based brush composite material according to the embodiment of the present invention was obtained.

[0098] The obtained brush had a flexural strength of 9.55 MPa, a compressive strength of 11.71 MPa, and a resistivity of 356 μΩ·m.

[0099] Example 13

[0100] Weigh the catalytic cracking slurry Ningxia slurry into the reactor, and add terephthalic acid and toluenesulfonic acid. The mass ratio of catalytic cracking slurry, terephthalic acid and toluenesulfonic acid is 10:3:0.75. Fix the reactor in an oil bath, heat and stir, and introduce N2 at a flow rate of 50mL / min. Heat to a reaction temperature of 150°C and keep the temperature constant. Water droplets will be generated during the reaction and the viscosity of the resin will increase. When the viscosity of the resin increases and entanglement occurs, stop the reaction. After cooling to room temperature, take out the product to obtain COPNA resin. The residual carbon rate of the obtained COPNA resin is 36.67%, and the β resin content is 15.38%.

[0101] COPNA resin and nanographite are crushed, dried and sieved to 200 meshes respectively, COPNA resin is completely dissolved in chloroform solution, and then nanographite is added, heated and stirred to obtain a uniformly mixed brush aggregate. The mass ratio of COPNA resin and nanographite is 15% COPNA resin and 85% nanographite.

[0102] The mixed brush aggregate is evaporated to dryness under oil bath stirring, and then dried in an oven. Then, it is fully crushed by ball mill and sieved to obtain dry brush aggregate powder. The brush aggregate powder is placed in a brush mold and pressed at 200℃ and 10MPa for 30min and maintained at pressure for 50min to obtain a brush blank. During the hot pressing process, the density of the molded brush is 1.73g / cm 3 The brush blank was placed in a tubular furnace for calcination, nitrogen was introduced at a nitrogen flow rate of 60 ml / min, the temperature was raised to 500°C at a rate of 0.25°C / min, and the calcination time was 2 hours. After calcination and molding, a high-performance COPNA resin-based brush composite material according to the embodiment of the present invention was obtained.

[0103] The obtained brush had a flexural strength of 8.72 MPa, a compressive strength of 13.55 MPa, and a resistivity of 360 μΩ·m.

[0104] Comparative Example 1

[0105] The difference from Example 1 is that the preparation method of COPNA resin is different, specifically:

[0106] Catalytic cracking slurry and Daqing slurry are weighed into two reactors respectively, concentrated sulfuric acid is added into one of the reactors under heating conditions for reaction, and sodium hydroxide is continuously added to obtain a derivative; mixed acid is added into the other reactor for reaction to obtain a derivative; and a condensation reaction is carried out using the reactivity of the two groups of derivative groups to obtain COPNA resin.

[0107] COPNA resin and colloidal graphite are crushed, dried and sieved to 200 meshes respectively, and COPNA resin is completely dissolved in chloroform solution, and then colloidal graphite is added, heated and stirred to obtain a uniformly mixed brush aggregate. The mass ratio of COPNA resin and colloidal graphite is 15% COPNA resin and 85% colloidal graphite.

[0108] The mixed brush aggregate is evaporated to dryness under stirring in an oil bath, and then further dried in an oven. Then, it is fully crushed using a ball mill and sieved to obtain dry brush aggregate powder. The brush aggregate powder is placed in a brush mold and pressed at 200℃ and 10MPa for 30 minutes and maintained at a pressure of 50 minutes to obtain a brush blank. During the hot pressing process, the density of the molded brush is 1.64g / cm 3 The brush blank was placed in a tubular furnace for calcination, nitrogen was introduced at a nitrogen flow rate of 60 ml / min, the temperature was raised to 300°C at a rate of 0.25°C / min, and the calcination time was 2 hours. After calcination and molding, a high-performance COPNA resin-based brush composite material according to the embodiment of the present invention was obtained.

[0109] The obtained brush had a flexural strength of 17.56 MPa, a compressive strength of 25.86 MPa, and a resistivity of 358 μΩ·m.

[0110] Table 1 Brush performance

[0111]

[0112]

[0113] As can be seen from Table 1, COPNA resin, graphite and calcination temperature have a great influence on the performance of the synthesized brush. From the results of Example 1 and Comparative Example 1, it can be seen that the preparation method of the present invention uses catalytic cracking oil slurry and a cross-linking agent to cross-link the COPNA resin under the action of a catalyst, which has excellent heat resistance and excellent adhesion, so that the prepared brush has excellent wear resistance and pressure resistance, and has good electrical conductivity; it can be used for high-quality, high-demand motors and engines.

[0114] Table 2 Brush performance comparison

[0115]

[0116] As shown in Table 2, the performance parameters of the resin brush of Example 1 of the present invention are compared with those of the Toyo 105S carbon brush of Japan, the IM824 brush of Morgan Electric Carbon Company of the United Kingdom, and the natural graphite brush for rotating electrical machines of GB 22673-2008-T. As can be seen from Table 2, the mechanical properties of the resin brush prepared by the preparation process of the embodiment of the present invention have reached the national standard for natural graphite brushes for rotating electrical machines, and the flexural strength, compressive strength and resistivity are better than those of the products of Toyo Company of Japan and Morgan Electric Carbon Company of the United Kingdom in the prior art.

[0117] The above embodiments are only used to help understand the method and core idea of ​​the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A method for preparing a high-performance COPNA resin-based brush composite material, characterized in that: The following steps are involved: S1: Weigh the catalytic cracking oil slurry into the reactor, add the crosslinking agent and the catalyst, fix the reactor in the oil bath, heat and stir, and introduce N2. When heated to the reaction temperature, the reaction occurs. During the reaction, water droplets will be generated and the viscosity of the resin will increase. When the viscosity of the resin increases to cause tangling, stop the reaction, cool, and take out the product to obtain COPNA resin; S2: COPNA resin and graphite are crushed, dried and sieved respectively, COPNA resin is completely dissolved in chloroform solution, and then graphite is added, heated and stirred to obtain a uniformly mixed brush aggregate; S3: The uniformly mixed brush aggregate is evaporated to dryness under stirring in an oil bath, and then further dried in an oven, and then fully crushed using a ball mill, and then sieved to obtain dry brush aggregate powder; S4: placing brush aggregate powder into a mold and performing hot pressing to obtain a brush blank; S5: calcining the brush blank in a N2 atmosphere to obtain a high-performance COPNA resin-based brush.

2. The preparation method according to claim 1, characterized in that: The mass ratio of the COPNA resin to the graphite is 10-30:70-90.

3. The preparation method according to claim 1, characterized in that: The carbon residue rate of the COPNA resin is 30%-50%, and the content of the β resin is 15%-50%.

4. The preparation method according to claim 1, characterized in that: The catalytic cracking slurry oil is Ningxia slurry oil or Daqing slurry oil.

5. The preparation method according to claim 1, characterized in that: The cross-linking agent is at least one of trioxymethylene, benzaldehyde, terephthalic alcohol, benzaldehyde, terephthaloyl chloride, terephthalaldehyde and divinylbenzene.

6. The preparation method according to claim 1, characterized in that: The catalyst is at least one of sulfuric acid, hydrochloric acid and toluenesulfonic acid.

7. The preparation method according to claim 1, characterized in that: Based on 100wt% of the added amount of catalytic cracking oil slurry, the added amount of the cross-linking agent is 20wt%-60wt%, and the added amount of the catalyst is 5wt%-15wt%.

8. The preparation method according to claim 1, characterized in that: The graphite is at least one of colloidal graphite, flake graphite and nanographite.

9. The preparation method according to claim 1, characterized in that: In step S1, the reaction temperature is 120-160°C.

10. The preparation method according to claim 1, characterized in that: In step S4, during the hot pressing process, the density of the formed brush is 1.4-2.2 g / cm 3 .

11. The preparation method according to claim 1, characterized in that: In step S4, during the hot pressing process, the hot pressing temperature is 150-200°C, the pressure is 10-50MPa, and the time is 30-80min.

12. A resin brush obtained by the preparation method according to any one of claims 1 to 11.

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