High-strength acid-resistant composite rubber material as well as preparation method and application thereof

Abstract

The invention relates to the technical field of industrial rubber roller materials, and particularly discloses a high-strength acid-resistant composite rubber material as well as a preparation method and application thereof. The high-strength acid-resistant composite rubber material is prepared from the following raw material components: a first rubber matrix, a second rubber matrix, inorganic filler, an antioxidant, an accelerant, an assistant crosslinker, a vulcanizing agent and a vulcanizing aid, wherein the first rubber matrix is prepared from tetrafluoroethylene-propylene rubber, fluororubber, nano titanium dioxide and polyurethane; the second rubber matrix comprises ethylene propylene diene monomer, ethylene-acrylate rubber and nano boron fibers; the inorganic filler comprises carbon black and nano barium sulfate. The composite rubber material provided by the invention has relatively high tensile strength, excellent acid resistance and relatively low Mooney viscosity. By utilizing the technical scheme of the invention, the problems of poor acid resistance, high Mooney viscosity and low tensile strength of the rubber material for the industrial rubber roller in the prior art are effectively solved, and a new design thought is developed for the rubber material for the industrial rubber roller.

Description

Technical Field

[0001] The present invention relates to the technical field of rubber materials for preparing industrial rubber rollers, and specifically discloses a high-strength acid-resistant composite rubber material, a preparation method thereof, and an application thereof. Background Art

[0002] A rubber roller is a roller-shaped product with a metal or other material as the core material and rubber coated on the outside and vulcanized. It is mainly applied in fields such as the paper industry, printing and dyeing industry, textile industry, printing industry, metallurgical industry, packaging machinery, and plastic processing. Among them, the rubber coated on the outside of the rubber roller directly determines the performance and application scenarios of the rubber roller. And with the rapid development of modern industry, the requirements for rubber materials are also getting higher and higher.

[0003] Rubber rollers often come into contact with various acidic media in industrial production, such as the nitric acid-hydrofluoric acid mixed solution (the concentration can reach 20%) in the pickling unit of the metallurgical industry, the acidic dampening solution (pH value 3.5 - 5.5) in the printing industry, etc. If the rubber roller is not acid-resistant, it will cause surface corrosion to produce sand holes and pits, which not only affects the product transmission quality, but also may cause equipment failures due to the exposure of the metal roller core.

[0004] Since chlorosulfonated polyethylene elastomer has excellent acid resistance and wear resistance, most of the existing commonly used acid-resistant rubber roller coating rubber materials are chlorosulfonated polyethylene elastomers. However, carbon tetrachloride pollution or lead pollution will be generated during the preparation process of chlorosulfonated polyethylene elastomer, which is not conducive to environmental protection. Moreover, the chlorosulfonated polyethylene elastomer has a relatively high Mooney viscosity and a relatively low tensile strength, and it is easy to have problems such as difficult extrusion or uneven winding during the preparation of rubber rollers, which affects the service life of the rubber rollers.

[0005] Based on this, researching and developing a rubber material with excellent acid resistance, high tensile strength, and low Mooney viscosity has important practical significance for the development of rubber materials for industrial rubber rollers. Summary of the Invention

[0006] Aiming at the problems of poor acid resistance, high Mooney viscosity, and low tensile strength of the rubber materials for industrial rubber rollers in the prior art, the present invention provides a high-strength acid-resistant composite rubber material, a preparation method thereof, and an application thereof. The raw material components of the high-strength acid-resistant composite rubber material include a first rubber matrix, a second rubber matrix, an inorganic filler, an antioxidant, an accelerator, a co-crosslinking agent, a vulcanizing agent, and a vulcanization aid; wherein, the first rubber matrix includes tetrapropyl fluoride rubber, fluororubber, nano-titanium dioxide, and polyurethane; the second rubber matrix includes ethylene propylene diene monomer rubber, ethylene-acrylate rubber, and nano-boron fiber; the inorganic filler includes carbon black and nano-barium sulfate. The composite rubber material provided by the present invention has a relatively high tensile strength, excellent acid resistance, and a relatively low Mooney viscosity, effectively making up for the deficiencies of the prior art.

[0007] To achieve the above-mentioned invention object, the present invention provides the following technical solutions: In the first aspect of the present invention, a high-strength acid-resistant composite rubber material is provided. The high-strength acid-resistant composite rubber material comprises the following raw material components in parts by mass: 40-50 parts of a first rubber matrix, 30-45 parts of a second rubber matrix, 5-10 parts of an inorganic filler, 1-5 parts of an antioxidant, 1-5 parts of an accelerator, 1-5 parts of a co-crosslinking agent, 1-5 parts of a vulcanizing agent, and 1-3 parts of a vulcanization aid; Among them, the first rubber matrix comprises tetrapropylene fluororubber, fluororubber, nano-titanium dioxide, and polyurethane; The second rubber matrix comprises ethylene propylene diene monomer rubber, ethylene-acrylate rubber, and nano-boron fiber; The inorganic filler comprises carbon black and nano-barium sulfate.

[0008] Compared with the prior art, the high-strength acid-resistant composite rubber material provided by the present invention comprises two rubber matrices. Among them, the first rubber matrix comprises tetrapropylene fluororubber, fluororubber, nano-titanium dioxide, and polyurethane. The molecular structure of tetrapropylene fluororubber contains groups such as fluorine atoms and propyl groups. The presence of these groups makes the tetrapropylene fluororubber molecules have high chemical stability. And due to the strong electronegativity of fluorine atoms and the steric hindrance effect of propyl groups, the two jointly act to greatly reduce the reaction probability between acidic substances and rubber molecules, thereby improving the acid resistance of the rubber material. A large number of C-F bonds exist in the molecular structure of fluororubber. The high bond energy makes the C-F bonds very stable, thus ensuring that fluororubber has strong stability and is not easily corroded by acidic substances. Nano-titanium dioxide has the characteristics of small size effect and high specific surface area. When it is uniformly dispersed in the rubber matrix, it can produce a strong interaction with rubber molecules, forming effective physical crosslinking points. These crosslinking points can uniformly transfer stress and prevent the expansion of rubber cracks, thereby significantly improving the tensile strength of the rubber material. At the same time, nano-titanium dioxide can fill the voids between rubber molecules to form a dense structure and prevent the intrusion of chemical substances, thereby improving the chemical corrosion resistance of the rubber material. The addition of polyurethane can effectively improve the fluidity of the rubber material, reduce the Mooney viscosity of the rubber, making it easier to flow and operate in the processing processes such as mixing and molding. It not only improves the processing efficiency but also reduces energy consumption.

[0009] Ethylene-acrylate rubber is an elastomer copolymerized from ethylene and acrylate monomers. In its molecular structure, the acrylate group belongs to a polar group, and the polar group can interact with ions in an acidic medium, such as forming hydrogen bonds or ionic dipole interactions. This interaction can form a structure similar to a protective film on the surface of the rubber material, preventing acidic substances from further penetrating into the rubber interior, thereby reducing the direct contact between acidic substances and rubber molecules and decreasing the possibility of rubber being corroded by acid. Nano boron fibers have high strength and modulus, which can effectively bear the externally applied stress and transfer the stress to the fibers, thus reducing the direct stress on the rubber molecular chains and avoiding their premature fracture. This enables the rubber material to withstand greater tensile force during the stretching process and significantly improves the tensile strength of the rubber material.

[0010] Carbon black can improve the processing performance of rubber. It can reduce the viscosity of rubber, increase the fluidity of rubber, make rubber easier to mix evenly with other compounding agents during processing, and can pass through the mold more smoothly, improving production efficiency and product quality. Nano barium sulfate has a small particle size and a large specific surface area. It can form a strong interfacial bonding force with rubber molecules, playing a role in strengthening and toughening, and improving the mechanical properties of rubber, such as tensile strength and elongation at break.

[0011] The present invention uses a first rubber matrix, a second rubber matrix, and inorganic fillers as the main raw materials, supplemented with antioxidants, accelerators, co-crosslinking agents, vulcanizing agents, and vulcanization aids to prepare a composite rubber material with good fluidity, high tensile strength, and excellent acid corrosion resistance, effectively solving the problems of poor acid resistance, high Mooney viscosity, and low tensile strength of the rubber materials used in industrial rubber rollers in the prior art, and providing a new design idea for rubber materials for industrial rubber rollers.

[0012] Preferably, the first rubber matrix comprises raw material components with the following mass percentages: 35%-50% of tetrapropylene fluoride rubber, 10%-15% of fluororubber, 10%-15% of nano titanium dioxide, and the balance of polyurethane.

[0013] More preferably, the particle size of the nano titanium dioxide is 50-100nm.

[0014] Preferably, the mass ratio of ethylene-propylene-diene monomer rubber, ethylene-acrylate rubber, and nano boron fibers in the second rubber matrix is 1:1:0.3-1:1:0.5.

[0015] Preferably, the inorganic filler is carbon black and nano barium sulfate with a mass ratio of 1:0.2-1:0.4.

[0016] More preferably, the length of the nano boron fibers is 80-120nm, and the elastic modulus is 200-400GPa.

[0017] Further preferably, the particle size of the carbon black is 10 - 20 μm.

[0018] Further preferably, the particle size of the nano barium sulfate is 50 - 100 nm.

[0019] Preferably, the antioxidant is any one or two of N - phenyl - β - naphthylamine, N,N'-diphenyl - p - phenylenediamine, N - isopropyl - N'-phenyl - p - phenylenediamine or N - (1,3 - dimethylbutyl) - N'-phenyl - p - phenylenediamine.

[0020] During the use of the rubber material, an oxidation reaction occurs, generating a large number of free radicals. These free radicals can initiate the breaking and cross - linking reactions of the rubber molecular chains, resulting in a deterioration of the rubber properties. The antioxidant can capture and convert them into relatively stable substances, thereby interrupting the free radical chain reaction and effectively delaying the aging process of the rubber material.

[0021] Preferably, the accelerator is any one or more of 2 - mercaptobenzothiazole, dibenzothiazole disulfide, tetramethylthiuram disulfide or tetraethylthiuram disulfide.

[0022] The addition of the accelerator helps to form a more uniform and dense cross - linked network structure, reducing the voids and defects inside the composite rubber material, enabling the rubber material to effectively block the intrusion of acidic molecules, and thus improving the acid - resistance of the rubber material. Moreover, the accelerator can also assist in improving the tensile properties and chemical stability of the rubber, ensuring the quality uniformity of the rubber material.

[0023] Preferably, the co - crosslinking agent is m - phenylenedimaleimide.

[0024] During the rubber vulcanization process, the co - crosslinking agent can react with the active sites on the rubber molecular chains to form more cross - link points, making the cross - linked network of the rubber material more dense. Moreover, the co - crosslinking agent can also make the filler more easily and uniformly dispersed in the rubber, avoiding the deterioration of the material properties caused by filler agglomeration.

[0025] Preferably, the vulcanizing agent is sulfur.

[0026] Preferably, the vulcanization aid is stearic acid.

[0027] The second aspect of the present invention provides a preparation method of the high - strength acid - resistant composite rubber material, comprising the following steps: Step 1: Weigh tetra - propylene fluoride rubber, fluororubber, nano - titanium dioxide and polyurethane according to the designed ratio. First, mix the tetra - propylene fluoride rubber and fluororubber evenly, conduct the first internal mixing to obtain a mixed rubber compound; add nano - titanium dioxide and polyurethane to the mixed rubber compound, conduct the second internal mixing, and discharge the rubber to obtain the first rubber matrix; Step 2: Weigh ethylene propylene diene monomer (EPDM), ethylene-acrylate rubber, and nano boron fibers according to the designed ratio. First, mix the EPDM and ethylene-acrylate rubber evenly and conduct the first stage of internal mixing. Then, add the nano boron fibers and conduct the second stage of internal mixing. After discharging the rubber, the second rubber matrix is obtained. Step 3: Weigh the first rubber matrix, the second rubber matrix, inorganic filler, antioxidant, accelerator, co-crosslinking agent, vulcanizing agent, and vulcanization aid according to the designed ratio. Mix the first rubber matrix, the second rubber matrix, and the inorganic filler evenly and conduct kneading to obtain a mixed rubber material. Add the remaining components except the accelerator and co-crosslinking agent to the mixed rubber material and conduct internal mixing. When the temperature of the rubber material drops to 60 - 70°C, add the accelerator and co-crosslinking agent, mix evenly, and discharge the rubber to obtain a high-strength acid-resistant composite rubber material.

[0028] Preferably, in Step 1, the temperature of the first stage of internal mixing is 120 - 140°C, and the time of the first stage of internal mixing is 3 - 5 minutes.

[0029] Preferably, in Step 1, the temperature of the second stage of internal mixing is 125 - 135°C, and the time of the second stage of internal mixing is 2 - 4 minutes.

[0030] Preferably, in Step 1, the temperature of discharging the rubber is 110 - 115°C.

[0031] Preferably, in Step 2, the temperature of the first stage of internal mixing is 130 - 150°C; the time of the first stage of internal mixing is 4 - 6 minutes.

[0032] Preferably, in Step 2, the temperature of the second stage of internal mixing is 135 - 140°C, and the time of the second stage of internal mixing is 3 - 4 minutes.

[0033] Preferably, in Step 2, the temperature of discharging the rubber is 105 - 110°C.

[0034] Preferably, in Step 3, the temperature of kneading is 140 - 150°C, and the time of kneading is 2 - 4 minutes.

[0035] Preferably, in Step 3, the temperature of internal mixing is 135 - 145°C, and the time of internal mixing is 1 - 3 minutes.

[0036] Preferably, in Step 3, the temperature of mixing is 120 - 130°C, and the time of mixing is 1 - 3 minutes.

[0037] Preferably, in Step 3, the temperature of discharging the rubber is 100 - 110°C.

[0038] The third aspect of the present invention provides the application of the high-strength acid-resistant composite rubber material or the high-strength acid-resistant composite rubber material prepared by using the preparation method of the high-strength acid-resistant composite rubber material in the preparation of industrial rubber rollers.

[0039] In summary, the high-strength acid-resistant composite rubber material provided by the present invention has high tensile strength, excellent acid resistance and low Mooney viscosity. Using the technical solution provided by the present invention effectively solves the problems of low tensile strength, poor acid resistance and high Mooney viscosity of the rubber material for industrial rubber rollers in the prior art, and opens up a new design idea for the development of the rubber material for industrial rubber rollers. Detailed Embodiments

[0040] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all 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.

[0041] Example 1 This example provides a high-strength acid-resistant composite rubber material and its preparation method, which specifically include the following content: The high-strength acid-resistant composite rubber material includes the following raw material components in parts by mass: 45 parts of the first rubber matrix, 40 parts of the second rubber matrix, 8 parts of inorganic filler, 4 parts of N-phenyl-β-naphthylamine, 3 parts of 2-mercaptobenzothiazole, 3 parts of m-phenylene bismaleimide, 4 parts of sulfur and 3 parts of stearic acid; The first rubber matrix includes the following raw material components in mass percentage: 45% of tetrapropyl fluororubber, 15% of fluororubber, 10% of nano-titanium dioxide and 30% of polyurethane; wherein, the particle size of the nano-titanium dioxide is 80 nm.

[0042] The second rubber matrix is ethylene propylene diene monomer rubber, ethylene-acrylate rubber and nano-boron fiber with a mass ratio of 1:1:0.4; wherein, the length of the nano-boron fiber is 100 nm and the elastic modulus is 300 GPa.

[0043] The inorganic filler is carbon black and nano-barium sulfate with a mass ratio of 1:0.3; wherein, the particle size of the carbon black is 20 μm; the particle size of the nano-barium sulfate is 70 nm.

[0044] The preparation method of the high-strength acid-resistant composite rubber material includes the following steps: Step 1: Weigh tetrapropyl fluororubber, fluororubber, nano-titanium dioxide and polyurethane according to the designed ratio. First, mix the tetrapropyl fluororubber and fluororubber evenly, and conduct primary kneading at 130 °C for 4 min to obtain a mixed rubber compound; add nano-titanium dioxide and polyurethane to the mixed rubber compound, conduct secondary kneading at 130 °C for 3 min, cool down to 110 °C, and discharge the rubber to obtain the first rubber matrix; Step 2: Weigh ethylene propylene diene monomer (EPDM), ethylene-acrylate rubber and nano-boron fiber according to the designed ratio. First, mix the EPDM and ethylene-acrylate rubber evenly, conduct primary kneading at 140 °C for 5 min, then add the nano-boron fiber, conduct secondary kneading at 138 °C for 4 min, cool down to 106 °C, and discharge the rubber to obtain the second rubber matrix; Step 3: Weigh the first rubber matrix, the second rubber matrix, inorganic filler, N-phenyl-β-naphthylamine, 2-mercaptobenzothiazole, m-phenylene bismaleimide, sulfur and stearic acid according to the designed ratio; mix the first rubber matrix, the second rubber matrix and the inorganic filler evenly, and conduct kneading at 145 °C for 3 min to obtain a mixed rubber compound; Add the remaining components except 2-mercaptobenzothiazole and m-phenylene bismaleimide to the mixed rubber compound, conduct kneading at 138 °C for 2 min. When the temperature of the rubber compound drops to 65 °C, add 2-mercaptobenzothiazole and m-phenylene bismaleimide, conduct mixing at 130 °C for 2 min, cool down to 110 °C, and discharge the rubber to obtain a high-strength acid-resistant composite rubber material.

[0045] Example 2 This example provides a high-strength acid-resistant composite rubber material and its preparation method, which specifically includes the following content: The high-strength acid-resistant composite rubber material includes the following raw material components in parts by mass: 40 parts of the first rubber matrix, 45 parts of the second rubber matrix, 5 parts of inorganic filler, 5 parts of N,N'-diphenyl-p-phenylenediamine, 5 parts of dibenzothiazole disulfide, 3 parts of m-phenylene bismaleimide, 4 parts of sulfur and 3 parts of stearic acid; The first rubber matrix includes the following raw material components in mass percentage: 35% of tetrapropyl fluororubber, 15% of fluororubber, 15% of nano-titanium dioxide and 35% of polyurethane; among them, the particle size of the nano-titanium dioxide is 100 nm.

[0046] The second rubber matrix is a mixture of EPDM, ethylene-acrylate rubber and nano-boron fiber with a mass ratio of 1:1:0.3; among them, the length of the nano-boron fiber is 120 nm and the elastic modulus is 400 GPa.

[0047] The inorganic filler is carbon black and nano barium sulfate with a mass ratio of 1:0.4; wherein, the particle size of the carbon black is 10 μm; the particle size of the nano barium sulfate is 50 nm.

[0048] The preparation method of the high-strength acid-resistant composite rubber material comprises the following steps: Step 1: Weigh tetrapropyl fluoride rubber, fluororubber, nano titanium dioxide and polyurethane according to the designed ratio. First, mix the tetrapropyl fluoride rubber and the fluororubber evenly, and conduct primary mixing for 4 min at 130 °C to obtain a mixed rubber compound; add the nano titanium dioxide and the polyurethane to the mixed rubber compound, conduct secondary mixing for 3 min at 130 °C, cool down to 110 °C, and discharge the rubber to obtain a first rubber matrix. Step 2: Weigh ethylene propylene diene monomer rubber, ethylene-acrylate rubber and nano boron fiber according to the designed ratio. First, mix the ethylene propylene diene monomer rubber and the ethylene-acrylate rubber evenly, conduct primary mixing for 5 min at 140 °C, then add the nano boron fiber, conduct secondary mixing for 4 min at 138 °C, cool down to 106 °C, and discharge the rubber to obtain a second rubber matrix. Step 3: Weigh the first rubber matrix, the second rubber matrix, the inorganic filler, N,N'-diphenyl-p-phenylenediamine, dibenzothiazyl disulfide, m-phenylene bismaleimide, sulfur and stearic acid according to the designed ratio; mix the first rubber matrix, the second rubber matrix and the inorganic filler evenly, and conduct kneading for 3 min at 145 °C to obtain a mixed rubber compound; Add the remaining components except dibenzothiazyl disulfide and m-phenylene bismaleimide to the mixed rubber compound, conduct mixing for 2 min at 138 °C. When the temperature of the rubber compound drops to 62 °C, add dibenzothiazyl disulfide and m-phenylene bismaleimide, conduct mixing for 2 min at 125 °C, cool down to 110 °C, and discharge the rubber to obtain the high-strength acid-resistant composite rubber material.

[0049] Example 3 This example provides a high-strength acid-resistant composite rubber material and its preparation method, which specifically includes the following content: The high-strength acid-resistant composite rubber material comprises the following raw material components in parts by mass: 50 parts of the first rubber matrix, 30 parts of the second rubber matrix, 10 parts of the inorganic filler, 2 parts of N-isopropyl-N'-phenyl-p-phenylenediamine, 3 parts of tetramethylthiuram disulfide, 3 parts of m-phenylene bismaleimide, 5 parts of sulfur and 3 parts of stearic acid; The first rubber matrix comprises the following raw material components in mass percentage: 50% of tetrapropyl fluoride rubber, 10% of fluororubber, 10% of nano titanium dioxide and 30% of polyurethane; wherein, the particle size of the nano titanium dioxide is 70 nm.

[0050] The second rubber matrix is ethylene propylene diene monomer (EPDM), ethylene-acrylate rubber and nano boron fibers with a mass ratio of 1:1:0.4; wherein, the length of the nano boron fibers is 80 nm and the elastic modulus is 250 GPa.

[0051] The inorganic filler is carbon black and nano barium sulfate with a mass ratio of 1:0.3; wherein, the particle size of the carbon black is 15 μm; the particle size of the nano barium sulfate is 60 nm.

[0052] The preparation method of the high-strength acid-resistant composite rubber material comprises the following steps: Step 1: Weigh tetrapropyl fluoride rubber, fluororubber, nano titanium dioxide and polyurethane according to the designed ratio. First, mix the tetrapropyl fluoride rubber and the fluororubber evenly, and conduct primary mixing for 4 min at 130 °C to obtain a mixed rubber compound; add the nano titanium dioxide and the polyurethane to the mixed rubber compound, conduct secondary mixing for 3 min at 130 °C, cool down to 110 °C, and discharge the rubber to obtain the first rubber matrix; Step 2: Weigh ethylene propylene diene monomer (EPDM), ethylene-acrylate rubber and nano boron fibers according to the designed ratio. First, mix the ethylene propylene diene monomer (EPDM) and the ethylene-acrylate rubber evenly, conduct primary mixing for 5 min at 140 °C, then add the nano boron fibers, conduct secondary mixing for 4 min at 138 °C, cool down to 106 °C, and discharge the rubber to obtain the second rubber matrix; Step 3: Weigh the first rubber matrix, the second rubber matrix, the inorganic filler, N-isopropyl-N'-phenyl-p-phenylenediamine, tetramethylthiuram disulfide, m-phenylene bismaleimide, sulfur and stearic acid according to the designed ratio; mix the first rubber matrix, the second rubber matrix and the inorganic filler evenly, and conduct kneading for 3 min at 145 °C to obtain a mixed rubber compound; Add the remaining components except 2-mercaptobenzothiazole and m-phenylene bismaleimide to the mixed rubber compound, conduct mixing for 2 min at 138 °C. When the temperature of the rubber compound drops to 68 °C, add tetramethylthiuram disulfide and m-phenylene bismaleimide, conduct mixing for 3 min at 120 °C, cool down to 100 °C, and discharge the rubber to obtain the high-strength acid-resistant composite rubber material.

[0053] Comparative Example 1 This comparative example provides a high-strength acid-resistant composite rubber material and its preparation method. The difference from Example 1 is that: the first rubber matrix is a chlorosulfonated polyethylene elastomer, and other components and preparation processes remain unchanged. The specific content is as follows: The high-strength acid-resistant composite rubber material comprises the following raw material components in parts by mass: 45 parts of chlorosulfonated polyethylene elastomer, 40 parts of the second rubber matrix, 8 parts of inorganic filler, 4 parts of N-phenyl-β-naphthylamine, 3 parts of 2-mercaptobenzothiazole, 3 parts of m-phenylene bismaleimide, 4 parts of sulfur and 3 parts of stearic acid; The second rubber matrix is ethylene propylene diene monomer (EPDM), ethylene-acrylate rubber and nano boron fibers with a mass ratio of 1:1:0.4; wherein, the length of the nano boron fibers is 100 nm and the elastic modulus is 300 GPa.

[0054] The inorganic filler is carbon black and nano barium sulfate with a mass ratio of 1:0.3; wherein, the particle size of the carbon black is 20 μm; the particle size of the nano barium sulfate is 70 nm.

[0055] The preparation method of the high-strength acid-resistant composite rubber material comprises the following steps: Step 1: Weigh EPDM, ethylene-acrylate rubber and nano boron fibers according to the designed ratio. First, mix EPDM and ethylene-acrylate rubber evenly, conduct primary mixing for 5 min at 140 °C, then add the nano boron fibers, conduct secondary mixing for 4 min at 138 °C, cool down to 106 °C, and discharge the rubber to obtain the second rubber matrix. Step 3: Weigh chlorosulfonated polyethylene elastomer, the second rubber matrix, inorganic filler, N-phenyl-β-naphthylamine, 2-mercaptobenzothiazole, m-phenylene bismaleimide, sulfur and stearic acid according to the designed ratio; mix the first rubber matrix, the second rubber matrix and the inorganic filler evenly, conduct kneading for 3 min at 145 °C to obtain a mixed rubber material. Add the remaining components except 2-mercaptobenzothiazole and m-phenylene bismaleimide to the mixed rubber material, conduct mixing for 2 min at 138 °C. When the temperature of the rubber material drops to 65 °C, add 2-mercaptobenzothiazole and m-phenylene bismaleimide, conduct mixing for 2 min at 130 °C, cool down to 110 °C, and discharge the rubber to obtain the high-strength acid-resistant composite rubber material.

[0056] Comparative Example 2 This comparative example provides a high-strength acid-resistant composite rubber material and its preparation method. The difference from Example 1 is that the second rubber matrix is replaced with an equal amount of chlorosulfonated polyethylene elastomer, and other components and preparation processes remain unchanged. The specific content is as follows: The high-strength acid-resistant composite rubber material comprises the following raw material components in parts by mass: 45 parts of the first rubber matrix, 40 parts of chlorosulfonated polyethylene elastomer, 8 parts of inorganic filler, 4 parts of N-phenyl-β-naphthylamine, 3 parts of 2-mercaptobenzothiazole, 3 parts of m-phenylene bismaleimide, 4 parts of sulfur and 3 parts of stearic acid; The first rubber matrix comprises the following raw material components in mass percentage: 45% of tetrapropyl fluoride rubber, 15% of fluororubber, 10% of nano titanium dioxide and 30% of polyurethane; wherein, the particle size of the nano titanium dioxide is 80 nm.

[0057] The inorganic filler is carbon black and nano barium sulfate with a mass ratio of 1:0.3; wherein, the particle size of the carbon black is 20 μm; the particle size of the nano barium sulfate is 70 nm.

[0058] The preparation method of the high-strength acid-resistant composite rubber material comprises the following steps: Step 1: Weigh tetrapropylene fluoride rubber, fluororubber, nano titanium dioxide and polyurethane according to the designed ratio. First, mix the tetrapropylene fluoride rubber and fluororubber evenly, and conduct primary mixing for 4 min at 130 °C to obtain a mixed rubber compound; add nano titanium dioxide and polyurethane to the mixed rubber compound, conduct secondary mixing for 3 min at 130 °C, cool down to 110 °C, and discharge the rubber to obtain a first rubber matrix. Step 2: Weigh the first rubber matrix, chlorosulfonated polyethylene elastomer, inorganic filler, N-phenyl-β-naphthylamine, 2-mercaptobenzothiazole, m-phenylene bismaleimide, sulfur and stearic acid according to the designed ratio; mix the first rubber matrix, second rubber matrix and inorganic filler evenly, and conduct kneading for 3 min at 145 °C to obtain a mixed rubber compound; Add the remaining components except 2-mercaptobenzothiazole and m-phenylene bismaleimide to the mixed rubber compound, conduct mixing for 2 min at 138 °C. When the temperature of the rubber compound drops to 65 °C, add 2-mercaptobenzothiazole and m-phenylene bismaleimide, conduct mixing for 2 min at 130 °C, cool down to 110 °C, and discharge the rubber to obtain the high-strength acid-resistant composite rubber material.

[0059] Comparative Example 3 This comparative example provides a high-strength acid-resistant composite rubber material and its preparation method. The difference from Example 1 is that the inorganic filler is replaced with an equal amount of white carbon black, and other components and preparation processes remain unchanged. The specific content is as follows: The high-strength acid-resistant composite rubber material comprises the following raw material components in parts by mass: 45 parts of the first rubber matrix, 40 parts of the second rubber matrix, 8 parts of white carbon black, 4 parts of N-phenyl-β-naphthylamine, 3 parts of 2-mercaptobenzothiazole, 3 parts of m-phenylene bismaleimide, 4 parts of sulfur and 3 parts of stearic acid; The first rubber matrix comprises the following raw material components in mass percentage: 45% of tetrapropylene fluoride rubber, 15% of fluororubber, 10% of nano titanium dioxide and 30% of polyurethane; wherein, the particle size of the nano titanium dioxide is 80 nm.

[0060] The second rubber matrix is ethylene propylene diene monomer rubber, ethylene-acrylate rubber and nano boron fiber with a mass ratio of 1:1:0.4; wherein, the length of the nano boron fiber is 100 nm and the elastic modulus is 300 GPa.

[0061] The preparation method of the high-strength acid-resistant composite rubber material comprises the following steps: Step 1: Weigh tetrapropyl fluororubber, fluororubber, nano titanium dioxide and polyurethane according to the designed ratio. First, mix the tetrapropyl fluororubber and fluororubber evenly, and conduct primary mixing for 4 min at 130 °C to obtain a mixed rubber compound; add nano titanium dioxide and polyurethane to the mixed rubber compound, conduct secondary mixing for 3 min at 130 °C, cool down to 110 °C, and discharge the rubber to obtain a first rubber matrix; Step 2: Weigh ethylene propylene diene monomer rubber, ethylene-acrylate rubber and nano boron fiber according to the designed ratio. First, mix the ethylene propylene diene monomer rubber and ethylene-acrylate rubber evenly, conduct primary mixing for 5 min at 140 °C, then add the nano boron fiber, conduct secondary mixing for 4 min at 138 °C, cool down to 106 °C, and discharge the rubber to obtain a second rubber matrix; Step 3: Weigh the first rubber matrix, the second rubber matrix, white carbon black, N-phenyl-β-naphthylamine, 2-mercaptobenzothiazole, m-phenylene bismaleimide, sulfur and stearic acid according to the designed ratio; mix the first rubber matrix, the second rubber matrix and the inorganic filler evenly, and conduct kneading for 3 min at 145 °C to obtain a mixed rubber compound; Add the remaining components except 2-mercaptobenzothiazole and m-phenylene bismaleimide to the mixed rubber compound, conduct mixing for 2 min at 138 °C. When the temperature of the rubber compound drops to 65 °C, add 2-mercaptobenzothiazole and m-phenylene bismaleimide, conduct mixing for 2 min at 130 °C, cool down to 110 °C, and discharge the rubber to obtain a high-strength acid-resistant composite rubber material.

[0062] In order to further reflect the technical effects of the present invention, the high-strength acid-resistant composite rubber materials obtained in Examples 1-3 and Comparative Examples 1-3 of the present invention were tested as follows: The Mooney viscosity was tested according to GB / T 1232.1-2000, the acid resistance was tested according to GB / T 1690-2006, and the acid cleaning solution was a 5 wt% hydrofluoric acid solution and a 16 wt% nitric acid solution with a volume ratio of 1:1. The tensile properties were tested according to GB / T 528-2009. The test results are shown in Table 1.

[0063] Table 1 Performance test results of each high-strength acid-resistant composite rubber material

[0064] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements or improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A high-strength acid-resistant composite rubber material, characterized in that: The high-strength acid-resistant composite rubber material comprises the following raw material components in parts by mass: 40-50 parts of a first rubber matrix, 30-45 parts of a second rubber matrix, 5-10 parts of an inorganic filler, 1-5 parts of an antioxidant, 1-5 parts of an accelerator, 1-5 parts of a co-crosslinking agent, 1-5 parts of a vulcanizing agent, and 1-3 parts of a vulcanization aid; Among them, the first rubber matrix includes tetrapropyl fluoride rubber, fluororubber, nano-titanium dioxide, and polyurethane; The second rubber matrix includes ethylene propylene diene monomer rubber, ethylene-acrylate rubber, and nano-boron fiber; The inorganic filler includes carbon black and nano-barium sulfate.

2. The high-strength acid-resistant composite rubber material according to claim 1, characterized in that: The first rubber matrix comprises the following raw material components in mass percentage: 35%-50% of tetrapropyl fluoride rubber, 10%-15% of fluororubber, 10%-15% of nano-titanium dioxide, and the balance of polyurethane.

3. The high-strength acid-resistant composite rubber material according to claim 1, characterized in that: The mass ratio of ethylene propylene diene monomer rubber, ethylene-acrylate rubber, and nano-boron fiber in the second rubber matrix is 1:1:0.3-1:1:0.5; and / or The inorganic filler is carbon black and nano-barium sulfate with a mass ratio of 1:0.2-1:0.

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4. The high-strength acid-resistant composite rubber material according to claim 3, wherein: The length of the nano-boron fiber is 80-120 nm, and the elastic modulus is 200-400 GPa; and / or The particle size of the carbon black is 10-20 μm; and / or The particle size of the nano-barium sulfate is 50-100 nm.

5. The high-strength acid-resistant composite rubber material according to claim 1, wherein: The antioxidant is any one or two of N-phenyl-β-naphthylamine, N,N'-diphenyl-p-phenylenediamine, N-isopropyl-N'-phenyl-p-phenylenediamine, or N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine; and / or The accelerator is any one or more of 2-mercaptobenzothiazole, dibenzothiazole disulfide, tetramethylthiuram disulfide, or tetraethylthiuram disulfide; and / or The co-crosslinking agent is m-phenylene bismaleimide; and / or The vulcanizing agent is sulfur; and / or The vulcanization aid is stearic acid.

6. The preparation method of the high-strength acid-resistant composite rubber material according to any one of claims 1-5, characterized in that: It includes the following steps: Step 1: Weigh tetrapropyl fluoride rubber, fluororubber, nano-titanium dioxide, and polyurethane according to the designed ratio. First, mix the tetrapropyl fluoride rubber and fluororubber evenly, conduct primary mixing in a mixer to obtain a mixed rubber compound; add nano-titanium dioxide and polyurethane to the mixed rubber compound, conduct secondary mixing in a mixer, and discharge the rubber to obtain the first rubber matrix; Step 2: Weigh ethylene propylene diene monomer rubber, ethylene-acrylate rubber, and nano-boron fiber according to the designed ratio. First, mix the ethylene propylene diene monomer rubber and ethylene-acrylate rubber evenly, conduct primary mixing in a mixer, and then add the nano-boron fiber for secondary mixing in a mixer, and discharge the rubber to obtain the second rubber matrix; Step 3: Weigh the first rubber matrix, the second rubber matrix, the inorganic filler, the antioxidant, the accelerator, the co-crosslinking agent, the vulcanizing agent, and the vulcanization aid according to the designed ratio; mix the first rubber matrix, the second rubber matrix, and the inorganic filler evenly, conduct kneading to obtain a mixed rubber material; add the remaining components except the accelerator and the co-crosslinking agent to the mixed rubber material, conduct mixing in a mixer. When the temperature of the rubber compound drops to 60-70 °C, add the accelerator and the co-crosslinking agent, mix evenly, and discharge the rubber to obtain the high-strength acid-resistant composite rubber material.

7. The preparation method of the high-strength acid-resistant composite rubber material according to claim 6, characterized in that: In Step 1, the temperature of the first stage of internal mixing is 120 - 140 °C, and the time of the first stage of internal mixing is 3 - 5 min; and / or In Step 1, the temperature of the second stage of internal mixing is 125 - 135 °C, and the time of the second stage of internal mixing is 2 - 4 min; and / or In Step 1, the temperature of the rubber discharging is 110 - 115 °C.

8. The preparation method of the high-strength acid-resistant composite rubber material according to claim 6, characterized in that: In Step 2, the temperature of the first stage of internal mixing is 130 - 150 °C; the time of the first stage of internal mixing is 4 - 6 min; and / or In Step 2, the temperature of the second stage of internal mixing is 135 - 140 °C, and the time of the second stage of internal mixing is 3 - 4 min; and / or In Step 2, the temperature of the rubber discharging is 105 - 110 °C.

9. The preparation method of the high-strength acid-resistant composite rubber material according to claim 6, characterized in that: In Step 3, the temperature of the kneading is 140 - 150 °C, and the time of the kneading is 2 - 4 min; and / or In Step 3, the temperature of the internal mixing is 135 - 145 °C, and the time of the internal mixing is 1 - 3 min; and / or In Step 3, the temperature of the mixing is 120 - 130 °C, and the time of the mixing is 1 - 3 min.

10. Use of a high-strength acid-resistant composite rubber material according to any one of claims 1 - 5 or a high-strength acid-resistant composite rubber material prepared by a preparation method of a high-strength acid-resistant composite rubber material according to any one of claims 6 - 9 in the preparation of an industrial rubber roller.

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