Aging-resistant rubber material for hydraulic pipe and preparation method thereof

Abstract

The present application relates to the technical field of rubber materials, and specifically discloses an anti-aging rubber material for hydraulic pipes and a preparation method thereof. The anti-aging rubber material is mainly made of the following raw materials in parts by weight: 70-90 parts of hydrogenated nitrile rubber, 10-30 parts of nitrile rubber, 9-11 parts of dioctyl phthalate, 4-6 parts of zinc oxide, 1-3 parts of stearic acid, 2-4 parts of sulfur, 0.3-0.8 parts of peroxide, 0.5-1.5 parts of accelerator, 45-55 parts of white carbon black, 10-20 parts of modified diatomite, and 2-4 parts of antioxidant; the modified diatomite is obtained by treating diatomite with 3-allyloxypropyl trimethoxysilane, N,N'-m-phenylene bismaleimide, and 3-(2-amino-5-bromo-3-pyridyl) ethyl acrylate. The anti-aging rubber material has the advantages of high tensile strength, high tear strength, and good aging resistance through the mutual cooperation between the raw materials, which meets market demand.

Description

Technical Field

[0001] The present application relates to the technical field of rubber materials, and more specifically, to an aging-resistant rubber material for hydraulic pipes and a preparation method thereof. Background Art

[0002] Hydraulic pipe is one of the important parts that cannot be ignored in modern industry. It is widely used in many fields such as mines, oil fields, metallurgy, engineering construction, ships, etc. Hydraulic pipe mainly transports oily liquids and aqueous liquids with certain pressure and temperature. Most manufacturers' hydraulic pipes are often made of rubber materials. Hydrogenated nitrile rubber has good oil resistance, chemical corrosion resistance, and ozone resistance, and has been used in hydraulic pipes. In the processing of hydraulic pipes, vulcanizers, accelerators, white carbon black, and antioxidants are often added to hydrogenated nitrile rubber, and the raw materials are mixed and vulcanized to obtain rubber materials. In actual processing, it is found that the rubber material obtained by using this formula has poor aging resistance, which affects the service life of the hydraulic pipe. Summary of the invention

[0003] In order to reduce the aging tensile strength loss rate of the aging-resistant rubber material, thereby improving the aging resistance, the present application provides an aging-resistant rubber material for hydraulic pipes and a preparation method thereof.

[0004] In the first aspect, the present application provides an aging-resistant rubber material for hydraulic pipes, which adopts the following technical solution:

[0005] The invention discloses an aging-resistant rubber material for hydraulic pipes. The aging-resistant rubber material is mainly made of the following raw materials in parts by weight: 70-90 parts of hydrogenated nitrile rubber, 10-30 parts of nitrile rubber, 9-11 parts of dioctyl phthalate, 4-6 parts of zinc oxide, 1-3 parts of stearic acid, 2-4 parts of sulfur, 0.3-0.8 parts of peroxide, 0.5-1.5 parts of accelerator, 45-55 parts of white carbon black, 10-20 parts of modified diatomaceous earth and 2-4 parts of antioxidant; the modified diatomaceous earth is obtained by treating diatomaceous earth with 3-allyloxypropyltrimethoxysilane, N,N'-m-phenylene bismaleimide and 3-(2-amino-5-bromo-3-pyridyl)ethyl acrylate.

[0006] The aging-resistant rubber material for hydraulic pipes of the present application has a tensile strength of >26MPa, a tear strength of >43kN / m, and an aging tensile strength loss rate of <5% through the mutual coordination between the raw materials. It exhibits the advantages of high tensile strength, high tear strength, and good aging resistance, and also makes the aging-resistant rubber material have better comprehensive performance to meet market demand.

[0007] Adding white carbon black to the raw materials of the aging-resistant rubber material has a reinforcing effect, which improves the strength and aging resistance of the aging-resistant rubber material. On this basis, modified diatomaceous earth is used to replace part of the white carbon black, forming the coexistence of white carbon black and modified diatomaceous earth, and the synergistic effect between them is utilized to enhance the three-dimensional network structure and improve the stability of the network structure. In the modified diatomaceous earth, 3-allyloxypropyl trimethoxysilane, N,N'-m-phenylene bismaleimide, 3-(2-amino-5-bromo-3-pyridyl) ethyl acrylate are grafted on the surface of the diatomaceous earth, and active groups such as phenyl, pyridyl, amine, ester, and imide are introduced, which not only increases the number of active groups, but also improves the activity of the modified diatomaceous earth, improves the compatibility, dispersion uniformity, and interface bonding force, enhances the interaction between it and white carbon black, improves the crosslinking density and integrity of the aging-resistant rubber material, reduces network structure defects, further improves the tensile strength, tear strength, and aging resistance of the aging-resistant rubber material, and prolongs the service life, which is suitable for the long-term and stable use of hydraulic pipes.

[0008] Optionally, the modified diatomaceous earth is prepared by the following method:

[0009] T1. Mix water and diatomaceous earth, add 3-allyloxypropyltrimethoxysilane, stir for 1-3 hours, filter and obtain a solid;

[0010] T2. Mix acetonitrile, tetrahydrofuran and solid matter, add N,N'-m-phenylene bismaleimide and 3-(2-amino-5-bromo-3-pyridyl) ethyl acrylate, add peroxide, stir for 2-4 hours, filter, wash and dry to obtain modified diatomaceous earth.

[0011] Optionally, the weight ratio of diatomaceous earth, 3-allyloxypropyltrimethoxysilane, N,N'-m-phenylene bismaleimide, and 3-(2-amino-5-bromo-3-pyridyl)ethyl acrylate is 200:(10-20):(7-9):(7-9).

[0012] In the preparation method of modified diatomite, firstly, in an aqueous system, 3-allyloxypropyl trimethoxysilane is grafted on the surface of diatomite and a carbon-carbon double bond is introduced, and then in an organic system formed by acetonitrile and tetrahydrofuran, free radicals released by peroxide are used to graft N,N'-m-phenylene bismaleimide and 3-(2-amino-5-bromo-3-pyridyl)ethyl acrylate on the surface of diatomite, thereby obtaining modified diatomite. The preparation method grafts on the surface of diatomite in steps, which is convenient for controlling the grafting reaction, ensuring the stability of the preparation of modified diatomite, and improving the stability of the network structure of the aging-resistant rubber material, improving the overall performance, so that the aging-resistant rubber material exhibits better tensile strength, tear strength and aging resistance, and prolongs the service life.

[0013] Optionally, in the method for preparing the modified diatomaceous earth, the weight ratio of the diatomaceous earth to the peroxide is 200:(0.3-0.5).

[0014] In the preparation method of modified diatomite, the amount of peroxide added is optimized to reduce the effect of too little addition on the grafting reaction and reduce the waste caused by too much addition. When the weight ratio of diatomite to peroxide is selected within the range of 200:(0.3-0.5), the stability of the grafting reaction can be ensured, and the stability of the preparation of modified diatomite can also be ensured.

[0015] Optionally, the weight ratio of diatomaceous earth, water, acetonitrile and tetrahydrofuran is 2:(17-23):(7-13):(7-13).

[0016] The amount of water added in step T1 is optimized to facilitate the diatomite to be fully dispersed in water, which is beneficial to the grafting reaction of 3-allyloxypropyltrimethoxysilane. The amount of acetonitrile and tetrahydrofuran added in step T2 is also optimized to facilitate the solid matter to be fully dispersed in the acetonitrile and tetrahydrofuran mixture, so that the solid matter and N,N'-m-phenylene bismaleimide, 3-(2-amino-5-bromo-3-pyridyl)ethyl acrylate, and peroxide are fully contacted and grafted to ensure the stability of the preparation of the modified diatomite and the use effect.

[0017] In multiple embodiments, the weight ratio of diatomaceous earth, water, acetonitrile and tetrahydrofuran is 2:20:10:10. The weight ratio can be set to 2:17:7:7, 2:17:7:13, 2:17:13:7, 2:17:13:13, 2:23:7:7, 2:23:7:13, 2:23:13:7, 2:23:13:13 as needed, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0018] Optionally, the average particle size of the diatomaceous earth used in the modified diatomaceous earth is 1-100 μm; the average particle size of the white carbon black is 100-300 μm. Preferably, the average particle size of the diatomaceous earth used in the modified diatomaceous earth is 1-50 μm. Preferably, the average particle size of the white carbon black is 100-200 μm.

[0019] Optimizing the average particle size of diatomaceous earth and white carbon black not only ensures the stability of the source, but also improves the uniformity of dispersion, enhances the interaction, improves the tensile strength and tear strength of aging-resistant rubber materials, reduces the aging tensile strength loss rate of aging-resistant rubber materials, and extends the stability and life of aging-resistant rubber materials.

[0020] In multiple embodiments, the average particle size of diatomaceous earth is 45 μm, and the average particle size can be set to 1 μm, 10 μm, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm as needed, but it is not limited to the listed values, and other values ​​not listed in the numerical range are also applicable. In multiple embodiments, the average particle size of white carbon black is 150 μm, and the average particle size can be set to 100 μm, 130 μm, 180 μm, 200 μm, 230 μm, 250 μm, 280 μm, 300 μm as needed, but it is not limited to the listed values, and other values ​​not listed in the numerical range are also applicable.

[0021] Optionally, the SiO2 mass content of the diatomaceous earth used in the modified diatomaceous earth is ≥ 80%; the BET specific surface area of ​​the white carbon black is 70-130m 2 / g.

[0022] Optionally, the mass content of acrylonitrile in the hydrogenated nitrile rubber is 25-45%, and the Mooney viscosity ML (1+4, 100°C) is 60-80; the mass content of acrylonitrile in the nitrile rubber is 30-40%, and the Mooney viscosity ML (1+4, 100°C) is 40-60.

[0023] In multiple embodiments, the mass content of acrylonitrile in the hydrogenated nitrile rubber is 35%, and the Mooney viscosity ML (1+4, 100°C) is 75. The mass content of acrylonitrile can be set to 25%, 30%, or 40% as needed, and the Mooney viscosity ML (1+4, 100°C) can also be set to 60, 65, 70, or 80 as needed, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0024] In multiple embodiments, the mass content of acrylonitrile in the nitrile rubber is 33%, and the Mooney viscosity ML (1+4, 100°C) is 52. The mass content of acrylonitrile can be set to 30%, 35%, 38%, or 40% as needed, and the Mooney viscosity ML (1+4, 100°C) can also be set to 40, 45, 50, 55, or 60 as needed, but is not limited to the listed values, and other unlisted values ​​within the numerical range are equally applicable.

[0025] Optionally, the peroxide is one or more of dicumyl peroxide, benzoyl peroxide, tert-butyl perbenzoate, and cyclohexanone peroxide. Preferably, the peroxide is dicumyl peroxide.

[0026] The peroxide is optimized to facilitate the selection of peroxide, and dicumyl peroxide, benzoyl peroxide, tert-butyl perbenzoate and cyclohexanone peroxide can release free radicals, increase the crosslinking density and uniformity of the aging-resistant rubber material, enhance the network structure, improve the integrity, and make the aging-resistant rubber material show better comprehensive performance.

[0027] Optionally, the accelerator is one or more of N-cyclohexyl-2-benzothiazole sulfenamide, dibenzothiazole disulfide, dibenzothiazole disulfide, and tetramethylthiuram disulfide. Preferably, the accelerator is N-cyclohexyl-2-benzothiazole sulfenamide.

[0028] The accelerator is optimized to facilitate the selection of the accelerator, and the accelerator can significantly improve the vulcanization efficiency, reduce the vulcanization time, and enhance the strength of the aging-resistant rubber material, making it suitable for the application of hydraulic pipes.

[0029] Optionally, the antioxidant is one or more of antioxidant 4020, antioxidant 4010NA, antioxidant RD, and antioxidant TNP. Preferably, the antioxidant is antioxidant 4020.

[0030] Optimizing the antioxidant makes it easier to select it, and the antioxidant has excellent antioxidant properties, which can effectively delay the aging process of aging-resistant rubber materials and improve the service life and stability of aging-resistant rubber materials.

[0031] In a second aspect, the present application provides a method for preparing an aging-resistant rubber material for a hydraulic pipe, which adopts the following technical solution:

[0032] A method for preparing an aging-resistant rubber material for a hydraulic pipe mainly comprises the following steps:

[0033] S1, mixing hydrogenated nitrile rubber, nitrile rubber and antioxidant for 3-5 minutes, adding stearic acid and dioctyl phthalate, mixing for 3-5 minutes, adding white carbon black and modified diatomaceous earth, mixing for 8-12 minutes, adding zinc oxide, sulfur, peroxide and accelerator, mixing for 4-6 minutes, taking out, standing at a temperature of 20-30° C. for 20-24 hours, and obtaining a mixed rubber;

[0034] S2. vulcanize the mixed rubber at a temperature of 160-170°C and a pressure of 8-12MPa for 30-50min, take it out, and dry it to obtain an aging-resistant rubber material.

[0035] The hydrogenated nitrile rubber, nitrile rubber, dioctyl phthalate, zinc oxide, stearic acid, sulfur, peroxide, accelerator, white carbon black, modified diatomaceous earth and antioxidant are mixed in steps to obtain a rubber mix, and then the rubber mix is ​​vulcanized to obtain an aging-resistant rubber material. This method is not only convenient for the preparation and control of the aging-resistant rubber material, but also allows the raw materials to be fully mixed, enhances dispersibility and processability, ensures the quality of the aging-resistant rubber material, and is suitable for large-scale industrial batch production.

[0036] In multiple embodiments, the temperature of the vulcanization treatment is 165°C, the pressure is 10MPa, and the time is 40min. The temperature can be set to 160°C, 162°C, 167°C, or 170°C as needed. The pressure can also be set to 8MPa, 9MPa, 11MPa, or 12MPa as needed. The time can also be set to 30min, 35min, 45min, or 50min as needed. However, the above values ​​are not limited to the above values, and other values ​​not listed within the range are also applicable.

[0037] In summary, this application has at least the following beneficial effects:

[0038] The aging-resistant rubber material for hydraulic pipes of the present application adds white carbon black and modified diatomaceous earth to the raw materials, grafts 3-allyloxypropyltrimethoxysilane, N,N'-m-phenylene bismaleimide, and 3-(2-amino-5-bromo-3-pyridyl)ethyl acrylate to the diatomaceous earth surface, and introduces active groups such as phenyl, pyridyl, amine, ester, and imide. The synergistic effect between them and the mutual coordination between other raw materials are utilized to enhance the three-dimensional network structure, improve the crosslinking density and integrity, so that the tensile strength of the aging-resistant rubber material is greater than 26MPa, the tear strength is greater than 43kN / m, and the aging tensile strength loss rate is less than 5%, showing the advantages of high tensile strength, high tear strength, and good aging resistance, and also making the aging-resistant rubber material have better comprehensive performance to meet market demand. DETAILED DESCRIPTION

[0039] In order to make the present application easier to understand, the present application will be further described in detail below in conjunction with the examples, which are merely illustrative and are not intended to limit the scope of application of the present application. The raw materials or components used in the present application can be obtained through commercial routes or conventional methods unless otherwise specified.

[0040] Preparation Example

[0041] Preparation Example 1

[0042] A modified diatomaceous earth is prepared by the following method:

[0043] T1. Add 200 g of diatomaceous earth to 2000 g of water at a rotation speed of 400 r / min, stir for 5 min, add 15 g of 3-allyloxypropyltrimethoxysilane, stir for 2 h, filter and obtain a solid.

[0044] Among them, the average particle size of diatomite is 45μm, and the mass content of SiO2 in diatomite is 87%.

[0045] T2, at a speed of 400r / min, add 1000g of tetrahydrofuran to 1000g of acetonitrile, and stir for 1min. Add the solid obtained in step T1, and stir for 5min. Add 8g of N,N'-m-phenylene bismaleimide and 8g of 3-(2-amino-5-bromo-3-pyridyl)ethyl acrylate, and stir for 5min. Add 0.4g of peroxide, stir for 3h, and filter. Wash once with acetonitrile, wash once with tetrahydrofuran, wash once with ethanol, wash once with water, and dry to obtain modified diatomite.

[0046] Wherein, the peroxide is benzoyl peroxide.

[0047] Preparation Example 2

[0048] A modified diatomaceous earth is prepared by the following method:

[0049] T1. Add 200 g of diatomaceous earth to 2000 g of water at a rotation speed of 400 r / min, stir for 5 min, add 10 g of 3-allyloxypropyltrimethoxysilane, stir for 1 h, filter and obtain a solid.

[0050] Among them, the average particle size of diatomite is 45μm, and the mass content of SiO2 in diatomite is 87%.

[0051] T2, at a speed of 400r / min, add 1000g of tetrahydrofuran to 1000g of acetonitrile, and stir for 1min. Add the solid obtained in step T1, and stir for 5min. Add 7g of N,N'-m-phenylene bismaleimide and 9g of 3-(2-amino-5-bromo-3-pyridyl)ethyl acrylate, and stir for 5min. Add 0.3g of peroxide, stir for 4h, and filter. Wash once with acetonitrile, wash once with tetrahydrofuran, wash once with ethanol, wash once with water, and dry to obtain modified diatomite.

[0052] Wherein, the peroxide is benzoyl peroxide.

[0053] Preparation Example 3

[0054] A modified diatomaceous earth is prepared by the following method:

[0055] T1. Add 200 g of diatomaceous earth to 2000 g of water at a rotation speed of 400 r / min, stir for 5 min, add 20 g of 3-allyloxypropyltrimethoxysilane, stir for 3 h, filter and obtain a solid.

[0056] Among them, the average particle size of diatomite is 45μm, and the mass content of SiO2 in diatomite is 87%.

[0057] T2, at a speed of 400r / min, add 1000g of tetrahydrofuran to 1000g of acetonitrile, and stir for 1min. Add the solid obtained in step T1, and stir for 5min. Add 9g of N,N'-m-phenylene bismaleimide and 7g of 3-(2-amino-5-bromo-3-pyridyl)ethyl acrylate, and stir for 5min. Add 0.4g of peroxide, stir for 2h, and filter. Wash once with acetonitrile, wash once with tetrahydrofuran, wash once with ethanol, wash once with water, and dry to obtain modified diatomite.

[0058] Wherein, the peroxide is benzoyl peroxide. Example

[0059] Table 1 Amount of each raw material used in aging-resistant rubber materials (unit: ×10g)

[0060] Example 1

[0061] An aging-resistant rubber material for hydraulic pipes, the raw materials and raw material ratios of which are shown in Table 1.

[0062] The mass content of acrylonitrile in hydrogenated nitrile rubber is 35%, and the Mooney viscosity ML (1+4, 100°C) is 75; the mass content of acrylonitrile in nitrile rubber is 33%, and the Mooney viscosity ML (1+4, 100°C) is 52; the peroxide is diisopropylbenzene peroxide; the accelerator is N-cyclohexyl-2-benzothiazole sulfonamide; the antioxidant is antioxidant 4020; the average particle size of white carbon black is 150μm, and the BET specific surface area is 90m 2 / g; the modified diatomaceous earth was prepared by the method of Preparation Example 1.

[0063] A method for preparing an aging-resistant rubber material for a hydraulic pipe mainly comprises the following steps:

[0064] S1. Add hydrogenated nitrile rubber, nitrile rubber and antioxidant into a mixer and mix for 4 minutes. Add stearic acid and dioctyl phthalate and mix for 4 minutes. Add white carbon black and modified diatomaceous earth and mix for 10 minutes. Add zinc oxide, sulfur, peroxide and accelerator and mix for 5 minutes. Take out and stand at 25°C for 22 hours to obtain a mixed rubber.

[0065] S2, adding the mixed rubber obtained in step S1 into a vulcanizer, vulcanizing for 40 minutes at a temperature of 165°C and a pressure of 10 MPa, taking out, drying for 2 hours at a temperature of 160°C, and obtaining an aging-resistant rubber material.

[0066] Example 2

[0067] An aging-resistant rubber material for hydraulic pipes, which differs from Example 1 in that the raw material ratio of the aging-resistant rubber material is different, and the raw material ratio of the aging-resistant rubber material is shown in Table 1.

[0068] Example 3

[0069] An aging-resistant rubber material for hydraulic pipes, which differs from Example 1 in that the raw material ratio of the aging-resistant rubber material is different, and the raw material ratio of the aging-resistant rubber material is shown in Table 1.

[0070] Example 4

[0071] An aging-resistant rubber material for hydraulic pipes is different from Example 1 in that the source of the modified diatomaceous earth in the raw materials of the aging-resistant rubber material is different, and the modified diatomaceous earth is prepared by the method of Preparation Example 2.

[0072] Example 5

[0073] An aging-resistant rubber material for hydraulic pipes is different from Example 1 in that the modified diatomaceous earth in the raw materials of the aging-resistant rubber material has a different source, and the modified diatomaceous earth is prepared by the method of Preparation Example 3.

[0074] Comparative Example

[0075] Comparative Example 1

[0076] An aging-resistant rubber material for hydraulic pipes is different from Example 1 in that an equal amount of white carbon black is used to replace modified diatomaceous earth in the raw materials of the aging-resistant rubber material.

[0077] Comparative Example 2

[0078] An aging-resistant rubber material for hydraulic pipes is different from Example 1 in that an equal amount of diatomaceous earth is used to replace white carbon black and modified diatomaceous earth in the raw materials of the aging-resistant rubber material.

[0079] Comparative Example 3

[0080] An aging-resistant rubber material for hydraulic pipes is different from Example 1 in that an equal amount of diatomaceous earth is used to replace modified diatomaceous earth in the raw materials of the aging-resistant rubber material.

[0081] Comparative Example 4

[0082] An aging-resistant rubber material for hydraulic pipes is different from Example 1 in that the source of modified diatomaceous earth in the raw materials of the aging-resistant rubber material is different.

[0083] The modified diatomaceous earth was prepared by the following method: 200 g of diatomaceous earth was added to 2000 g of water at a rotation speed of 400 r / min, and stirred for 5 min. 31 g of 3-allyloxypropyltrimethoxysilane was added, and stirred for 2 h, and filtered to obtain a solid.

[0084] Among them, the average particle size of diatomite is 45μm, and the mass content of SiO2 in diatomite is 87%.

[0085] Comparative Example 5

[0086] An aging-resistant rubber material for hydraulic pipes is different from Example 1 in that the source of modified diatomaceous earth in the raw materials of the aging-resistant rubber material is different.

[0087] The modified diatomaceous earth was prepared by the following method: 200 g of diatomaceous earth was added to 2000 g of water at a rotation speed of 400 r / min, and stirred for 5 min. 31 g of 3-aminopropyltrimethoxysilane was added, and stirred for 2 h, and filtered to obtain a solid.

[0088] Among them, the average particle size of diatomite is 45μm, and the mass content of SiO2 in diatomite is 87%.

[0089] Comparative Example 6

[0090] An aging-resistant rubber material for hydraulic pipes, which differs from Example 1 in that, in the raw materials of the aging-resistant rubber material, in the preparation method of modified diatomaceous earth, an equal amount of N,N'-m-phenylene bismaleimide is used to replace 3-(2-amino-5-bromo-3-pyridyl)ethyl acrylate.

[0091] Comparative Example 7

[0092] An aging-resistant rubber material for hydraulic pipes, which differs from Example 1 in that, in the raw materials of the aging-resistant rubber material, in the preparation method of modified diatomaceous earth, an equal amount of 3-(2-amino-5-bromo-3-pyridyl)ethyl acrylate is used to replace N,N'-m-phenylene bismaleimide.

[0093] Performance Testing

[0094] The aging-resistant rubber materials obtained in Examples 1-5 and Comparative Examples 1-7 were respectively taken, and the following performance tests were performed on the aging-resistant rubber materials. The test results are shown in Table 2.

[0095] Among them, the tensile strength of aging-resistant rubber materials is tested in accordance with GB / T528-2009 "Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber".

[0096] According to GB / T529-2008 “Determination of tear strength of vulcanized rubber or thermoplastic rubber”, the tear strength of aging-resistant rubber materials is tested.

[0097] According to GB / T3512-2014 "Hot air accelerated aging and heat resistance test for vulcanized rubber or thermoplastic rubber", the aging tensile strength loss rate of aging resistant rubber materials is tested. The smaller the aging tensile strength loss rate, the better the aging resistance of the aging resistant rubber material.

[0098] Moreover, the aging of the aging-resistant rubber material is hot air aging, and the hot air aging temperature is 150°C and the time is 72 hours. Aging tensile strength loss rate / (%)=(tensile strength before aging-tensile strength after aging) / tensile strength before aging×100%.

[0099] Table 2 Test results

[0100]

[0101] As can be seen from Table 2, the aging-resistant rubber material of the present application has high tensile strength and tear strength, with a tensile strength of 26.68-28.75 MPa and a tear strength of 43.37-44.96 kN / m, showing the characteristics of high tensile strength and high tear strength. It also has a low aging tensile strength loss rate, which is 2.28-4.57%, showing high aging resistance and meeting market demand.

[0102] Comparative Examples 1-3 are compared. In Comparative Example 1, white carbon black is added to the raw materials of the aging-resistant rubber material; in Comparative Example 2, diatomaceous earth is added to the raw materials of the aging-resistant rubber material; in Comparative Example 3, white carbon black and diatomaceous earth are added to the raw materials of the aging-resistant rubber material. It can be seen that adding white carbon black and diatomaceous earth to the raw materials of the aging-resistant rubber material at the same time and utilizing the synergistic effect between them effectively increases the tensile strength, tear strength and aging resistance.

[0103] Comparative Examples 3-4 are compared. In Comparative Example 3, diatomaceous earth is added to the raw materials of the aging-resistant rubber material; in Comparative Example 4, modified diatomaceous earth is added to the raw materials of the aging-resistant material, and 3-allyloxypropyltrimethoxysilane is used to treat the diatomaceous earth. It can be seen that modifying the diatomaceous earth can improve the use effect of the modified diatomaceous earth. Combined with Comparative Example 5, modified diatomaceous earth is added to the raw materials of the aging-resistant material of Comparative Example 5, and 3-aminopropyltrimethoxysilane is used to treat the diatomaceous earth. It can be seen that different organic substances grafted on the surface of diatomaceous earth have different effects on the use of diatomaceous earth.

[0104] Comparative Example 4, Comparative Examples 6-7, and Example 1 are compared, and Comparative Example 4 is used as the basis. Compared with Comparative Example 4, in Comparative Example 6, in the modified diatomite preparation method, N, N'-m-phenylene bismaleimide is used to treat the solid; in Comparative Example 7, compared with Comparative Example 4, in the modified diatomite preparation method, 3-(2-amino-5-bromo-3-pyridyl) ethyl acrylate is used to treat the solid; in Example 1, compared with Comparative Example 4, in the modified diatomite preparation method, N, N'-m-phenylene bismaleimide and 3-(2-amino-5-bromo-3-pyridyl) ethyl acrylate are used to treat the solid. It can be seen that on the basis of grafting 3-allyloxypropyltrimethoxysilane on the surface of diatomite, N,N'-m-phenylene bismaleimide and 3-(2-amino-5-bromo-3-pyridyl)ethyl acrylate are further grafted, and active groups such as phenyl, pyridyl, amine, ester, and imide are introduced to enhance the interaction between the modified diatomite and silica, enhance the cross-linked network structure, reduce structural defects, further improve the tensile strength, tear strength and aging resistance, and make the aging-resistant rubber material show better comprehensive performance.

[0105] It should be noted that the embodiments described above are only used to explain the present application and do not constitute any limitation to the present application. The present application is described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory words, rather than restrictive words. The present application may be modified as specified within the scope of the claims of the present application, and the present invention may be revised without departing from the scope and spirit of the present application. Although the present application described therein relates to specific methods, materials and embodiments, it does not mean that the present application is limited to the specific examples disclosed therein. On the contrary, the present application can be extended to all other methods and applications with the same functions.

Claims

1. An aging-resistant rubber material for hydraulic pipes, characterized in that: The aging-resistant rubber material is mainly made of the following raw materials in parts by weight: 70-90 parts of hydrogenated nitrile rubber, 10-30 parts of nitrile rubber, 9-11 parts of dioctyl phthalate, 4-6 parts of zinc oxide, 1-3 parts of stearic acid, 2-4 parts of sulfur, 0.3-0.8 parts of peroxide, 0.5-1.5 parts of accelerator, 45-55 parts of white carbon black, 10-20 parts of modified diatomaceous earth, and 2-4 parts of antioxidant; the modified diatomaceous earth is obtained by treating diatomaceous earth with 3-allyloxypropyltrimethoxysilane, N,N'-m-phenylene bismaleimide, and 3-(2-amino-5-bromo-3-pyridyl)ethyl acrylate; The modified diatomaceous earth is prepared by the following method: T1. Mix water and diatomaceous earth, add 3-allyloxypropyltrimethoxysilane, stir for 1-3 hours, filter and obtain a solid; T2. Mix acetonitrile, tetrahydrofuran and solid matter, add N,N'-m-phenylene bismaleimide and 3-(2-amino-5-bromo-3-pyridyl) ethyl acrylate, add peroxide, stir for 2-4 hours, filter, wash and dry to obtain modified diatomaceous earth.

2. The aging-resistant rubber material for hydraulic pipe according to claim 1, characterized in that: The weight ratio of diatomaceous earth, 3-allyloxypropyltrimethoxysilane, N,N'-m-phenylene bismaleimide and 3-(2-amino-5-bromo-3-pyridyl)ethyl acrylate is 200:(10-20):(7-9):(7-9).

3. The anti-aging rubber material for hydraulic pipe according to claim 1, characterized in that: In the preparation method of the modified diatomaceous earth, the weight ratio of the diatomaceous earth to the peroxide is 200:(0.3-0.5).

4. The anti-aging rubber material for hydraulic pipe according to claim 1, characterized in that: The weight ratio of diatomaceous earth, water, acetonitrile and tetrahydrofuran is 2:(17-23):(7-13):(7-13).

5. The anti-aging rubber material for hydraulic pipe according to claim 1, characterized in that: The average particle size of the diatomaceous earth used in the modified diatomaceous earth is 1-100 μm; the average particle size of the white carbon black is 100-300 μm.

6. The anti-aging rubber material for hydraulic pipe according to claim 1, characterized in that: The peroxide is one or more of dicumyl peroxide, benzoyl peroxide, tert-butyl perbenzoate and cyclohexanone peroxide.

7. The anti-aging rubber material for hydraulic pipe according to claim 1, characterized in that: The accelerator is one or more of N-cyclohexyl-2-benzothiazole sulfenamide, dibenzothiazyl disulfide, dibenzothiazyl disulfide, and tetramethylthiuram disulfide.

8. The anti-aging rubber material for hydraulic pipe according to claim 1, characterized in that: The antioxidant is one or more of antioxidant 4020, antioxidant 4010NA, antioxidant RD, and antioxidant TNP.

9. A method for preparing an aging-resistant rubber material for hydraulic pipe according to any one of claims 1 to 8, characterized in that: The main steps are as follows: S1, mixing hydrogenated nitrile rubber, nitrile rubber and antioxidant for 3-5 minutes, adding stearic acid and dioctyl phthalate, mixing for 3-5 minutes, adding white carbon black and modified diatomaceous earth, mixing for 8-12 minutes, adding zinc oxide, sulfur, peroxide and accelerator, mixing for 4-6 minutes, taking out, standing at a temperature of 20-30° C. for 20-24 hours, and obtaining a mixed rubber; S2. vulcanize the mixed rubber for 30-50 minutes at a temperature of 160-170°C and a pressure of 8-12MPa, take it out, and dry it to obtain an aging-resistant rubber material.

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