A high-performance mining rubber product based on wet-process masterbatch and its preparation method

Abstract

This invention belongs to the field of rubber material technology, specifically relating to a high-performance mining rubber product based on wet-process masterbatch and its preparation method. The preparation method of the rubber product of this invention includes the following steps: S1, pre-dispersing low-hysteresis carbon black with deionized water at high speed to obtain a first carbon black slurry, and then combining it with natural rubber latex to obtain a carbon black / natural rubber wet-process masterbatch; S2, pre-dispersing high-abrasion-resistant carbon black with deionized water at high speed to obtain a second carbon black slurry, and then combining it with styrene-butadiene rubber latex to obtain a carbon black / styrene-butadiene rubber wet-process masterbatch; S3, performing a first-stage mixing of the carbon black / natural rubber wet-process masterbatch and the carbon black / styrene-butadiene rubber wet-process masterbatch to obtain a masterbatch matrix; S4, mixing the masterbatch matrix with other raw materials for a second-stage mixing and a third-stage mixing to obtain a high-performance mining rubber product. This invention achieves properties such as low hysteresis heat generation, high cut resistance, high tear resistance, and high abrasion resistance in the rubber compound through the synergistic effect of the dual wet-process masterbatch system.

Description

Technical Field

[0001] This invention belongs to the field of rubber materials technology, specifically relating to a high-performance mining rubber product prepared based on wet-process masterbatch and its preparation method. Background Technology

[0002] Engineering vehicles and mining machinery tires are used for a long time on rough roads with gravel, rocks, and sharp bumps. During operation, they are subjected to heavy impacts, cutting by sharp materials, and repeated compression deformation. Therefore, the tire tread rubber has extremely high requirements for cut resistance, tear resistance, low heat generation, and wear resistance. Currently, traditional engineering vehicle tire compounds mostly use natural rubber as a single matrix or a dry-mixing system of natural rubber / styrene-butadiene rubber, which has obvious technical shortcomings: First, in the traditional dry-mixing process, carbon black filler is prone to agglomeration, resulting in poor dispersion uniformity, weak interfacial bonding between rubber and filler, numerous internal defects in the compound, large lag loss under dynamic stress, and severe heat generation during continuous tire driving, which can easily lead to problems such as tread delamination, bulges, and accelerated aging, significantly shortening tire lifespan; Second, while single natural rubber compounds have excellent toughness, they lack cut resistance and abrasion resistance, while single styrene-butadiene rubber compounds are abrasion-resistant and cut-resistant but have poor low-temperature toughness and impact resistance. Conventional simple blending systems cannot achieve both low heat generation and strong cut resistance, making them prone to tread cut damage, chipping, tearing, and breakage on sharp roads in mining areas.

[0003] Compared to dry mixing, wet mixing masterbatch achieves the mixing and dispersion of fillers and rubber in the liquid phase, which solves the problems of difficult filler dispersion, high energy consumption, and pollution associated with dry mixing. In current wet mixing processes, pre-processed fillers such as carbon black are often made into aqueous dispersions, which are then thoroughly mixed with rubber latex. The rubber / carbon black masterbatch is then prepared through processes such as coagulation, dehydration, and drying. Wet mixing has advantages such as being green, environmentally friendly, energy-saving, and requiring simple equipment. However, conventional wet masterbatch formulations only contain a single rubber type, and the wet mixing processes for different rubber types vary significantly, making it difficult to prepare multiphase rubber systems.

[0004] Therefore, this invention innovatively adopts a dual wet-process masterbatch compounding system, which prepares two functional masterbatches through differentiated wet-process technology, and combines precise mixing and blending process with optimized formula to solve the defects of existing technology such as high heat generation, poor cut resistance and weak adaptability to working conditions. Summary of the Invention

[0005] The purpose of this invention is to provide a high-performance mining rubber product based on wet-process masterbatch and its preparation method. This invention achieves comprehensive performance of low hysteresis heat generation, high cut resistance, high tear resistance, and high abrasion resistance in the rubber compound through the synergistic effect of a dual wet-process masterbatch system and functionalized formulation. It is suitable for heavy-load and harsh working conditions in mining areas and aims to overcome the problems of high dynamic heat generation, weak cut resistance, poor adaptability to harsh road surfaces, and short service life of existing mining rubber products.

[0006] To achieve this objective, the present invention adopts the following technical solution: In a first aspect, the present invention provides a method for preparing high-performance mining rubber products based on wet-process masterbatch, comprising the following steps: S1. Low-hysteresis carbon black is pre-dispersed with deionized water by high-speed stirring to obtain a first carbon black slurry. The first carbon black slurry is then mixed with natural rubber latex by a continuous high-pressure jet process to prepare carbon black / natural rubber wet masterbatch. S2. High abrasion-resistant carbon black is pre-dispersed with deionized water by high-speed stirring to obtain a second carbon black slurry. The second carbon black slurry is then mixed with styrene-butadiene rubber latex by a flocculation wet process to prepare carbon black / styrene-butadiene rubber wet masterbatch. S3. The carbon black / natural rubber wet masterbatch from step S1 and the carbon black / styrene-butadiene rubber wet masterbatch from step S2 are mixed in a first stage to obtain the masterbatch matrix. S4. The masterbatch matrix described in step S3 is mixed with zinc oxide, stearic acid, antioxidant 4020, microcrystalline wax, and tackifying resin for two-stage mixing to obtain intermediate mixing material; the intermediate mixing material is mixed with sulfur and accelerator for three-stage mixing, pressed into sheets on an open mill, and vulcanized to obtain high-performance mining rubber products based on wet masterbatch.

[0007] As a preferred embodiment, the preparation steps of the carbon black / natural rubber wet-process masterbatch in step S1 are as follows: by weight, 40-70 parts of low-hysteresis carbon black and 1300-2300 parts of deionized water are mixed and pre-dispersed by stirring at a speed of 2000-3000 r / min for 50-60 min to obtain a first carbon black slurry; 1300-2300 parts of the first carbon black slurry and 167 parts of natural rubber latex with a solid content of 60% are added to a high-pressure jetting device, the jetting pressure is controlled at 80-120 MPa and the flow rate is 300-350 m / s, and a high-speed counter-jetting jet is performed. The resulting masterbatch is filtered and dried until the moisture content is ≤0.8% to obtain the carbon black / natural rubber wet-process masterbatch.

[0008] As a preferred embodiment, the weight percentage of the low-hysteresis carbon black can be 40 parts, 50 parts, 60 parts, or 70 parts, etc.

[0009] This invention uses a high-speed counter-jetting jet to instantaneously homogenize natural latex, relying on high-pressure collision to achieve nanoscale composite flocculation of carbon black and rubber.

[0010] As a preferred embodiment, the specific surface area of ​​the low-hysteresis carbon black is 122~138 m². 2 / g, external surface area is 116~130×10 -5 m 3 / kg, ash content ≤0.8%.

[0011] This invention ensures sufficient and effective interfacial sites by controlling the specific surface area and external surface area of ​​low-hysteresis carbon black. When rubber products are subjected to cutting by sharp objects or strong tearing stress, the low-hysteresis carbon black with high specific surface area and external surface area prevents the initiation and rapid propagation of cracks by optimizing interfacial interactions, thereby significantly improving the tear strength and cut resistance of the product. It also significantly reduces Akron abrasion volume by reducing stress concentration points under stress. In addition, the effective interfacial bonding will not cause a large amount of molecular slip due to weak interfacial bonding, nor will it cause the rubber chain segments to be completely locked due to excessive bonding, thereby reducing the temperature rise caused by compression heat generation.

[0012] As a preferred embodiment, the preparation steps of the carbon black / styrene-butadiene rubber wet-process masterbatch in step S2 are as follows: by weight, 40-70 parts of high abrasion-resistant carbon black are mixed with 1300-2300 parts of deionized water and stirred and pre-dispersed for 60-80 minutes at a speed of 1500-2500 r / min to obtain a second carbon black slurry; 1300-2300 parts of the second carbon black slurry are added to 435 parts of styrene-butadiene rubber latex with a solid content of 23% and stirred at a speed of 600-800 r / min for 6-8 hours at 50-60℃; then 40-50 parts of coagulant are added and stirred to precipitate flocculation; the mixture is filtered, washed with deionized water, and dried at 60-80℃ until the moisture content is ≤0.8% to obtain the carbon black / styrene-butadiene rubber wet-process masterbatch.

[0013] As a preferred embodiment, the weight percentage of the high abrasion-resistant carbon black can be 40 parts, 50 parts, 60 parts, or 70 parts, etc.

[0014] As a preferred embodiment, the preparation method of the high abrasion-resistant carbon black is as follows: 10-20 parts by weight of carbon black are added to 400-500 parts by weight of a 30% hydrogen peroxide solution and ultrasonically dispersed for 30-40 minutes. Then, the mixture is heated to 60°C and refluxed with stirring for 24-30 hours. The mixture is then filtered, washed with water, and dried to obtain hydroxylated carbon black. 1800-1900 parts by weight of anhydrous ethanol and 100-200 parts by weight of deionized water are mixed and then 40-50 parts by weight of γ-glycidyl etheroxypropyltrimethoxysilane is added and ultrasonically dispersed for 30-40 minutes. The carbon black is ultrasonically dispersed for 15-25 minutes, then 10-20 parts of the hydroxylated carbon black are added and ultrasonically dispersed for 2-4 hours. The mixture is then stirred and refluxed at 78°C for 6-8 hours, filtered, washed with anhydrous ethanol, and vacuum dried to obtain epoxidized carbon black. 10-20 parts of the epoxidized carbon black are added to 1800-2000 parts of anhydrous ethanol and ultrasonically dispersed for 60-80 minutes. Then 30-40 parts of amino POSS are added and the mixture is heated to 60°C and stirred and refluxed for 12-16 hours. The mixture is then filtered, washed with water, and dried to obtain high abrasion-resistant carbon black.

[0015] This invention first uses carbon black as raw material and oxidizes it with hydrogen peroxide to introduce hydroxyl groups on the surface of the carbon black, providing reaction sites for the next silane coupling reaction. Then, the hydroxylated carbon black is treated with γ-glycidoxypropyltrimethoxysilane. While the silane coupling agent is hydrolyzed and condensed onto the carbon black surface, the terminal epoxy groups are also retained. Finally, the amino group of POSS undergoes a ring-opening reaction with the introduced epoxy groups, and POSS with a rigid cage structure is grafted onto the carbon black surface through chemical bonding, thus obtaining high wear-resistant carbon black containing POSS.

[0016] As a preferred embodiment, the coagulant is one of calcium chloride, aluminum chloride, sodium chloride, magnesium chloride, and dinitrile diamine formaldehyde condensate; the mass concentration fraction of the aqueous coagulant solution is 2-10%.

[0017] As a preferred embodiment, the mixing step in step S3 is as follows: by weight, carbon black / natural rubber wet masterbatch and carbon black / styrene-butadiene rubber wet masterbatch are put into an internal mixer and mixed at 90~110℃ for 3~5 minutes and then left to stand for 24~30 hours to obtain the masterbatch matrix.

[0018] The mass ratio of the carbon black / natural rubber wet-process masterbatch to the carbon black / styrene-butadiene rubber wet-process masterbatch is (8~9):(5~6).

[0019] As a preferred embodiment, the two-stage mixing step in step S4 is as follows: by weight, 150 parts of the masterbatch matrix are added to an internal mixer, followed by 4-5 parts of zinc oxide, 1-2 parts of stearic acid, 0.5-1.0 parts of antioxidant 4020, 0.5-1.0 parts of microcrystalline wax, and 4-5 parts of tackifying resin. The two-stage mixing is carried out for 3-6 minutes, and the temperature is controlled at ≤165℃ for debinding to obtain the intermediate mixing material.

[0020] As a preferred embodiment, the zinc oxide may be present in parts by weight of 4, 4.2, 4.4, 4.6, 4.8, or 5.0 parts, etc.

[0021] As a preferred embodiment, the stearic acid may be present in parts by weight of 1.0, 1.2, 1.4, 16, 1.8, or 2.0 parts, etc.

[0022] As a preferred embodiment, the antioxidant 4020 can be present in parts by weight of 0.5, 0.6, 0.7, 0.8, 0.9, or 1.0 parts, etc.

[0023] As a preferred embodiment, the weight parts of the microcrystalline wax can be 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, or 1.0 parts, etc.

[0024] As a preferred embodiment, the tackifying resin may be present in parts by weight of 4, 4.2, 4.4, 4.6, 4.8, or 5.0 parts, etc.

[0025] As a preferred embodiment, the tackifying resin is an alkylphenol resin.

[0026] As a preferred embodiment, the three-stage mixing step in step S4 is as follows: by weight, the intermediate mixing material is put into a mixer, and then 1-2 parts of sulfur and 0.8-1.2 parts of accelerator are added. The mixture is mixed in three stages for 3-5 minutes, and the temperature is controlled at ≤105℃ for debinding.

[0027] As a preferred embodiment, the sulfur may be present in parts by weight of 1.0, 1.2, 1.4, 16, 1.8, or 2.0 parts, etc.

[0028] As a preferred embodiment, the accelerator may be present in weight parts of 0.8, 0.9, 1.0, 1.1, or 1.2 parts, etc.

[0029] As a preferred embodiment, the accelerator is accelerator CZ or accelerator DZ.

[0030] As a preferred embodiment, the vulcanization conditions in step S4 are: vulcanization temperature of 140~150℃ and vulcanization time of 20~30min.

[0031] Secondly, the present invention provides a high-performance mining rubber product prepared based on wet-process masterbatch by the preparation method described in the first aspect.

[0032] Compared with the prior art, the advantages and beneficial effects of the present invention are as follows: (1) This invention uses a dual-differentiated wet-process masterbatch preparation + dual masterbatch compounding synergy + segmented controllable internal mixing process. Targeting the characteristics of natural rubber and styrene-butadiene rubber matrices, dedicated wet-processes are used to prepare functional masterbatches. The natural rubber system employs a continuous high-pressure jet method to maximize the preservation of the rubber molecular chain integrity and achieve ultra-low hysteresis heat generation. The styrene-butadiene rubber system employs a stirring mixing and flocculation method to enhance filler wetting and interfacial bonding, significantly improving cut resistance and abrasion resistance. The two functional masterbatches are compounded with a dedicated additive system, and after segmented internal mixing, low-temperature final mixing, and vulcanization molding, a mineral rubber product with an extremely balanced comprehensive performance is obtained.

[0033] (2) This invention adopts a wet-process masterbatch system, realizing a dual wet-process masterbatch compound synergistic system. It uses low-heat-generating natural rubber wet-process masterbatch + high-cut-resistant styrene-butadiene rubber wet-process masterbatch to completely solve the performance shortcomings of a single rubber system and the bottleneck that wet mixing cannot achieve a multiphase rubber system. At the same time, it takes into account the multiple properties required for mining tires, such as low dynamic hysteresis, fatigue resistance, high cut resistance, and high wear resistance, breaking through the bottleneck that the properties of traditional blended rubber compounds cannot be compatible.

[0034] (3) The wet process of the present invention has the advantage of extreme dispersion. Through wet co-coagulation of latex and carbon black slurry, carbon black is uniformly dispersed in rubber latex at the nanoscale, which completely eliminates the filler agglomeration that is difficult to avoid in dry mixing. At the same time, through the reinforcement of the filler-rubber interface, the interface slippage and frictional heat generation are reduced.

[0035] (4) The POSS introduced by the high wear-resistant carbon black of the present invention has an inorganic cage-type nanostructure with high hardness and high rigidity, which can effectively anchor the rubber molecular chain to restrict the slippage and breakage of the molecular chain under the action of external force, and improve the tear resistance of rubber products. At the same time, POSS can construct a nano-level hard wear-resistant protective layer to ensure good wear resistance and cut resistance. In addition, POSS modification effectively improves the interfacial compatibility between carbon black and rubber matrix, weakens the filler agglomeration phenomenon, optimizes the regularity of rubber crosslinking network, and reduces ineffective energy consumption and heat accumulation during dynamic deformation process, thereby effectively reducing the temperature rise of rubber products during compression heat generation. Detailed Implementation

[0036] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0037] The sources of some components in the examples and comparative examples are as follows: Low-hysteresis carbon black I, model MH163, with a specific surface area of ​​135 m² 2 / g, with an external surface area of ​​128×10 -5 m 3 / kg, ash content 0.68%, purchased from Jiangxi Black Cat Carbon Black Co., Ltd.; Hydrogen peroxide solution, catalog number H112515, with a mass concentration of 20%, was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd. γ-glycidoxypropyltrimethoxysilane, CAS No. 2530-83-8, was purchased from Shanghai Maclean Biochemical Technology Co., Ltd. Amino POSS, item number 9502028, was purchased from Forsmann Technology (Beijing) Co., Ltd. Zinc oxide, CAS No. 1314-13-2, was purchased from Shanghai Maclean Biochemical Technology Co., Ltd. Stearic acid, CAS No. 57-11-4, purchased from Shanghai Maclean Biochemical Technology Co., Ltd. Antioxidant 4020, CAS No. 793-24-8, was purchased from Nanjing Tonghe Chemical Co., Ltd. Microcrystalline wax, product number C304670, was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd. Alkylphenol resin, model 551, purchased from Shenzhen Yunlin Chemical Co., Ltd. Sulfur, CAS No. 7704-34-9, purchased from Shandong Hubin Rubber Technology Co., Ltd. Accelerator CZ, CAS No. 95-33-0, was purchased from Nanjing Tonghe Chemical Co., Ltd. Accelerator DZ, CAS No. 4979-32-2, was purchased from Nanjing Tonghe Chemical Co., Ltd.

[0038] Example 1 This embodiment provides a method for preparing high-performance mining rubber products based on wet-process masterbatch, including the following steps: S1. By weight, 50 parts of low-hysteresis carbon black I (model MH163) and 1670 parts of deionized water are mixed and pre-dispersed by stirring at a speed of 2500 r / min for 60 min to obtain the first carbon black slurry. 1670 parts of the first carbon black slurry and 167 parts of natural rubber latex with a solid content of 60% are added to a high-pressure jetting device. The jetting pressure is controlled at 100 MPa and the flow rate is 320 m / s. High-speed counter-jetting jetting is performed. The resulting masterbatch is filtered and dried until the moisture content is ≤0.8% to obtain carbon black / natural rubber wet-process masterbatch.

[0039] S2. The preparation steps of the carbon black / styrene-butadiene rubber wet process masterbatch in step S2 are as follows: by weight, 50 parts of high abrasion-resistant carbon black and 1670 parts of deionized water are mixed and pre-dispersed by stirring at a speed of 1800 r / min for 670 min to obtain a second carbon black slurry; 1670 parts of the second carbon black slurry are added to 435 parts of styrene-butadiene rubber latex with a solid content of 23%, and stirred at a speed of 700 r / min for 7 h at 57 °C. Then, 48 parts of calcium chloride aqueous solution with a mass concentration of 5% are added and stirred to precipitate flocculation. The mixture is filtered, washed with deionized water, and dried at 70 °C until the moisture content is ≤0.8% to obtain the carbon black / styrene-butadiene rubber wet process masterbatch.

[0040] S3. By weight, carbon black / natural rubber wet masterbatch and carbon black / styrene-butadiene rubber wet masterbatch with a mass ratio of 9:6 are put into an internal mixer and mixed at 110°C for 3 minutes and then left to stand for 24 hours to obtain the masterbatch matrix.

[0041] S4. By weight, 150 parts of the masterbatch matrix are added to an internal mixer, followed by 5 parts of zinc oxide, 2 parts of stearic acid, 1.0 part of antioxidant 4020, 1.0 part of microcrystalline wax, and 5 parts of alkylphenol resin. The mixture is then mixed for 3 minutes in two stages, and the temperature is controlled at 162°C for discharge to obtain intermediate compound. The intermediate compound is then added to an internal mixer, followed by 2 parts of sulfur and 1.2 parts of accelerator CZ. The mixture is then mixed for 3 minutes in three stages, and the temperature is controlled at 103°C for discharge. The mixture is then pressed into sheets using an open mill and vulcanized at 150°C for 20 minutes to obtain a high-performance mining rubber product prepared based on wet-process masterbatch.

[0042] Preparation of the high abrasion-resistant carbon black: By weight, 20 parts of carbon black were added to 500 parts of a 30% hydrogen peroxide solution and ultrasonically dispersed for 40 min. The mixture was then heated to 60°C and refluxed with stirring for 30 h. After filtration, washing with water, and drying, hydroxylated carbon black was obtained. 1900 parts of anhydrous ethanol and 100 parts of deionized water were mixed, and 50 parts of γ-glycidyl etheroxypropyltrimethoxysilane were added and ultrasonically dispersed for 25 min. Then, 20 parts of the hydroxylated carbon black were added and ultrasonically dispersed for 4 h. The mixture was then stirred and refluxed at 78°C for 8 h. After filtration, washing with anhydrous ethanol, and vacuum drying, epoxide carbon black was obtained. 20 parts of the epoxide carbon black were added to 2000 parts of anhydrous ethanol and ultrasonically dispersed for 80 min. Then, 40 parts of amino POSS were added and the mixture was heated to 60°C and refluxed with stirring for 16 h. After filtration, washing with water, and drying, high abrasion-resistant carbon black was obtained.

[0043] Comparative Example 1 This comparative example describes a method for preparing a rubber product, comprising the following steps: S1. By weight, add 60 parts of natural rubber dry rubber and 40 parts of styrene-butadiene rubber dry rubber to a mixer and plasticize for 1 minute. Then add 30 parts of low hysteresis carbon black MH163 and 20 parts of high abrasion-resistant carbon black and mix for 3 minutes. Then add 5 parts of zinc oxide, 2 parts of stearic acid, 1.0 part of antioxidant 4020, 1.0 part of microcrystalline wax and 5 parts of alkylphenol resin and mix for 3 minutes. Control the temperature at 162℃ to discharge the rubber and obtain the intermediate compound. S2. The intermediate compound is fed into an internal mixer with 2 parts sulfur and 1.2 parts accelerator CZ, and mixed for 3 minutes. The temperature is controlled at 103°C for degassing. The mixture is then pressed into sheets using an open mill and vulcanized at 150°C for 20 minutes to obtain rubber products.

[0044] Comparative Example 2 This comparative example describes a method for preparing a rubber product, comprising the following steps: S1. By weight, add 90 parts of carbon black / natural rubber wet masterbatch and 40 parts of styrene-butadiene rubber dry rubber to a mixer and plasticize for 1 minute. Then add 20 parts of high abrasion-resistant carbon black and mix for 3 minutes. Then add 5 parts of zinc oxide, 2 parts of stearic acid, 1.0 part of antioxidant 4020, 1.0 part of microcrystalline wax, and 5 parts of alkylphenol resin and mix for 3 minutes. Control the temperature at 162℃ for debinding to obtain the intermediate compound. S2. The intermediate compound is fed into an internal mixer with 2 parts sulfur and 1.2 parts accelerator CZ, and mixed for 3 minutes. The temperature is controlled at 103°C for degassing. The mixture is then pressed into sheets using an open mill and vulcanized at 150°C for 20 minutes to obtain rubber products.

[0045] Comparative Example 3 This comparative example describes a method for preparing a rubber product, comprising the following steps: S1. By weight, add 60 parts of carbon black / styrene-butadiene rubber wet masterbatch and 60 parts of natural rubber dry rubber to a mixer and plasticize for 1 minute. Then add 30 parts of carbon black MH163 and mix for 3 minutes. Then add 5 parts of zinc oxide, 2 parts of stearic acid, 1.0 part of antioxidant 4020, 1.0 part of microcrystalline wax, and 5 parts of alkylphenol resin and mix for 3 minutes. Control the temperature at 162℃ for debinding to obtain the intermediate compound. S2. The intermediate compound is fed into an internal mixer with 2 parts sulfur and 1.2 parts accelerator CZ and mixed at 100°C for 8 minutes. The mixture is then discharged at 103°C. The mixture is pressed into sheets using an open mill and vulcanized at 150°C for 20 minutes to obtain rubber products.

[0046] Performance testing (1) Hardness test: The test shall be conducted in accordance with the requirements of GB / T 39693.4-2025 Determination of hardness of vulcanized rubber or thermoplastic rubber - Part 4: Determination of indentation hardness by Shore hardness tester (Shore hardness).

[0047] (2) Tensile property test: The test shall be conducted in accordance with the requirements of GB / T 528-2009 Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber.

[0048] (3) Tear strength test: The test shall be conducted in accordance with the requirements of GB / T 529-2008 Determination of tear strength of vulcanized rubber or thermoplastic rubber (trouser-shaped, right-angled and crescent-shaped specimens).

[0049] (4) Abrasion resistance test: The test shall be conducted in accordance with the requirements of GB / T 1689-2014 Determination of abrasion resistance of vulcanized rubber (using Akron abrasion tester).

[0050] (5) Cut resistance test: The rubber dynamic cut resistance tester was used to determine the sample rotation speed of 750 rpm, the cutting frequency of 60 times / minute, and the test time of 15 minutes. The cut resistance was evaluated by the cutting loss mass.

[0051] (6) Compression heat generation temperature rise test: The test shall be conducted in accordance with the requirements of GB / T 1687.3-2016 Determination of temperature rise and fatigue resistance of vulcanized rubber in flexural test Part 3: Compression flexural test (constant strain type)

[0052] Table 1 Performance Test Results

[0053] This invention first pre-disperses low-hysteresis carbon black with deionized water at high speed to obtain a first carbon black slurry, which is then combined with natural rubber latex to prepare a carbon black / natural rubber wet-process masterbatch. Next, high-abrasion-resistant carbon black is pre-dispersed with deionized water at high speed to obtain a second carbon black slurry, which is then combined with styrene-butadiene rubber latex to prepare a carbon black / styrene-butadiene rubber wet-process masterbatch. Then, the carbon black / natural rubber wet-process masterbatch and the carbon black / styrene-butadiene rubber wet-process masterbatch are mixed in a first-stage compounding process to obtain a masterbatch matrix. Finally, the masterbatch matrix is ​​mixed with zinc oxide, stearic acid, antioxidant, microcrystalline wax, and tackifying resin for a second-stage compounding process to obtain a compounding intermediate. The compounding intermediate is then mixed with sulfur and an accelerator for a third-stage compounding process. The mixture is then pressed into sheets using a two-roll mill and vulcanized to obtain a high-performance mining rubber product based on the wet-process masterbatch.

[0054] Compared to Example 1, the dry mixing process for preparing rubber products resulted in decreased tear strength, poorer abrasion resistance and cut resistance, and increased compression heat generation (Comparative Example 1). The wet mixing technology achieved nanoscale uniform dispersion of carbon black in the rubber matrix, eliminating the filler agglomeration defects that are difficult to avoid in dry mixing. Compared to dry mixing, the tear strength of the rubber compound was significantly improved, abrasion resistance was greatly enhanced, cut resistance was significantly strengthened, and dynamic heat generation was significantly reduced. The dual wet masterbatch compound system achieves a synergistic breakthrough in both cut resistance and low heat generation, fully meeting the requirements for heavy-duty extreme working conditions in mining.

[0055] Compared to Example 1, without the addition of carbon black / styrene-butadiene rubber wet masterbatch, the material's tear strength decreased, abrasion resistance and cut resistance deteriorated, and compression heat generation temperature rise increased (Comparative Example 2); compared to Example 1, without the addition of carbon black / natural rubber wet masterbatch, the material's tear strength decreased, abrasion resistance and cut resistance deteriorated, and compression heat generation temperature rise increased (Comparative Example 3). The dual wet masterbatch system, when combined, forms a high-strength, high-modulus composite material, providing excellent abrasion resistance and cut resistance. The synergistic effect of the two systems allows the compound to maintain high abrasion resistance and high cut resistance while achieving a balance with low heat generation. Using only one wet masterbatch system in combination with a dry masterbatch system is insufficient to achieve optimal performance; the dual wet masterbatch system comprehensively outperforms the dry masterbatch system or the comparative scheme of a single wet masterbatch combined with a dry masterbatch.

Claims

1. A method for preparing high-performance mining rubber products based on wet-process masterbatch, characterized in that, Includes the following steps: S1. Low-hysteresis carbon black is pre-dispersed with deionized water by high-speed stirring to obtain a first carbon black slurry. The first carbon black slurry is then mixed with natural rubber latex by a continuous high-pressure jet process to prepare carbon black / natural rubber wet masterbatch. S2. High abrasion-resistant carbon black is pre-dispersed with deionized water by high-speed stirring to obtain a second carbon black slurry. The second carbon black slurry is then mixed with styrene-butadiene rubber latex by a flocculation wet process to prepare carbon black / styrene-butadiene rubber wet masterbatch. S3. The carbon black / natural rubber wet masterbatch from step S1 and the carbon black / styrene-butadiene rubber wet masterbatch from step S2 are mixed in a first stage to obtain the masterbatch matrix. S4. The masterbatch matrix described in step S3 is mixed with zinc oxide, stearic acid, antioxidant 4020, microcrystalline wax, and tackifying resin for two-stage mixing to obtain intermediate mixing material; the intermediate mixing material is mixed with sulfur and accelerator for three-stage mixing, pressed into sheets on an open mill, and vulcanized to obtain high-performance mining rubber products based on wet masterbatch.

2. The method for preparing high-performance mining rubber products based on wet-process masterbatch according to claim 1, characterized in that, The preparation steps of the carbon black / natural rubber wet process masterbatch in step S1 are as follows: by weight, 40-70 parts of low hysteresis carbon black and 1300-2300 parts of deionized water are mixed and pre-dispersed by stirring at a speed of 2000-3000 r / min for 50-60 min to obtain the first carbon black slurry; 1300-2300 parts of the first carbon black slurry and 167 parts of natural rubber latex with a solid content of 60% are added to a high-pressure jetting device, the jetting pressure is controlled at 80-120 MPa and the flow rate is 300-350 m / s, and a high-speed counter-jetting jet is performed. The obtained masterbatch is filtered and dried until the moisture content is ≤0.8% to obtain the carbon black / natural rubber wet process masterbatch.

3. The method for preparing high-performance mining rubber products based on wet-process masterbatch according to claim 2, characterized in that, The specific surface area of ​​the low-hysteresis carbon black is 122~138 m². 2 / g, external surface area is 116~130×10 -5 m 3 / kg, ash content ≤0.8%.

4. The method for preparing high-performance mining rubber products based on wet-process masterbatch according to claim 1, characterized in that, The preparation steps of the carbon black / styrene-butadiene rubber wet process masterbatch in step S2 are as follows: by weight, 40-70 parts of high abrasion-resistant carbon black and 1300-2300 parts of deionized water are mixed and pre-dispersed by stirring at a speed of 1500-2500 r / min for 60-80 min to obtain a second carbon black slurry; 1300-2300 parts of the second carbon black slurry are added to 435 parts of styrene-butadiene rubber latex with a solid content of 23% and stirred at a speed of 600-800 r / min at 50-60℃ for 6-8 h; then 40-50 parts of coagulant are added and stirred to precipitate flocculation; the mixture is filtered, washed with deionized water, and dried at 60-80℃ until the moisture content is ≤0.8% to obtain the carbon black / styrene-butadiene rubber wet process masterbatch.

5. The method for preparing high-performance mining rubber products based on wet-process masterbatch according to claim 4, characterized in that, The preparation method of the high abrasion-resistant carbon black is as follows: 10-20 parts by weight of carbon black are added to 400-500 parts by weight of a 30% hydrogen peroxide solution and ultrasonically dispersed for 30-40 minutes. The mixture is then heated to 60°C and refluxed with stirring for 24-30 hours. After filtration, washing with water, and drying, hydroxylated carbon black is obtained. 1800-1900 parts by weight of anhydrous ethanol and 100-200 parts by weight of deionized water are mixed, and then 40-50 parts by weight of γ-glycidyl etheroxypropyltrimethoxysilane are added and ultrasonically dispersed for 15 minutes. After ~25 min, add 10~20 parts of the hydroxylated carbon black and ultrasonically disperse for 2~4 h. Then stir and reflux at 78℃ for 6~8 h, filter, wash with anhydrous ethanol, and vacuum dry to obtain epoxidized carbon black. Add 10~20 parts of the epoxidized carbon black to 1800~2000 parts of anhydrous ethanol and ultrasonically disperse for 60~80 min. Then add 30~40 parts of aminoPOSS and heat to 60℃ and stir and reflux for 12~16 h. Filter, wash with water, and dry to obtain high abrasion-resistant carbon black.

6. The method for preparing high-performance mining rubber products based on wet-process masterbatch according to claim 4, characterized in that, The coagulant is one of calcium chloride, aluminum chloride, sodium chloride, magnesium chloride, and dinitrile diamine formaldehyde condensate; the mass concentration fraction of the aqueous solution of the coagulant is 2-10%.

7. The method for preparing high-performance mining rubber products based on wet-process masterbatch according to claim 1, characterized in that, The mixing step described in step S3 is as follows: by weight, carbon black / natural rubber wet masterbatch and carbon black / styrene-butadiene rubber wet masterbatch with a mass ratio of (8~9):(5~6) are put into an internal mixer and mixed at 90~110℃ for 3~5 minutes and then left to stand for 24~30 hours to obtain the masterbatch matrix.

8. The method for preparing high-performance mining rubber products based on wet-process masterbatch according to claim 1, characterized in that, The two-stage mixing step in step S4 is as follows: by weight, the masterbatch matrix is ​​put into an internal mixer, and then 4-5 parts of zinc oxide, 1-2 parts of stearic acid, 0.5-1.0 parts of antioxidant 4020, 0.5-1.0 parts of microcrystalline wax, and 4-5 parts of tackifying resin are added. The two-stage mixing is carried out for 3-6 minutes, and the temperature is controlled at ≤165℃ for debinding to obtain the intermediate mixing material.

9. The method for preparing high-performance mining rubber products based on wet-process masterbatch according to claim 1, characterized in that, The three-stage mixing process in step S4 is as follows: by weight, the intermediate mixing material is put into an internal mixer, and then 1-2 parts of sulfur and 0.8-1.2 parts of accelerator are added. The mixture is then mixed in three stages for 3-5 minutes at 90-100℃, and the temperature is controlled to be ≤105℃ for debinding.

10. A high-performance mining rubber product prepared based on wet-process masterbatch, characterized in that, It is prepared by the preparation method according to any one of claims 1 to 9.

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