A high-flexibility rubber material for hydraulic pipe and preparation method thereof

Abstract

The present application relates to the technical field of rubber materials, and specifically discloses a highly flexible rubber material for hydraulic pipes and a preparation method thereof. The rubber material is mainly made of the following raw materials: nitrile rubber, chloroprene rubber, hyperbranched fluoropolymer, dioctyl phthalate, zinc oxide, magnesium oxide, stearic acid, sulfur, accelerator, carbon black, white carbon black, coupling agent, antioxidant; the hyperbranched fluoropolymer is obtained by reacting 2-octenyl succinic anhydride, 3-(2-aminoethylamino)propylamine, diamine, 4,4,4-trifluorobutyric acid, and p-aminophenylacetic acid. The rubber material, through the mutual coordination between the raw materials, has the advantages of high tensile strength, high elongation at break, low compression permanent deformation rate, high resilience, and good flexibility, and can adapt to the application of hydraulic pipes, enhance reliability and safety, and meet market demand.

Description

Technical Field

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

[0002] With the continuous advancement of industrial technology, hydraulic pipes have also developed rapidly. Common hydraulic pipes on the market mainly include steel pipes, copper pipes, brass pipes, rubber pipes, nylon pipes, plastic pipes, etc. For rubber hydraulic pipes, they are mainly used for hydraulic transmission and liquid transmission, for example, in engineering machinery, petroleum, chemical industry, agriculture, construction, mining, metallurgy, shipbuilding and other industries. The rubber material used in rubber hydraulic pipes generally includes nitrile rubber, zinc oxide, stearic acid, sulfur, accelerators, fillers, and antioxidants. The raw materials are mixed and vulcanized to obtain rubber materials. The rubber material obtained by this formula can improve the strength of the rubber material by adding fillers to the raw materials. However, when the amount of fillers reaches more than 50% of the total weight of nitrile rubber, the compression permanent deformation performance of the rubber material is increased, thereby affecting the resilience and flexibility of the rubber material. Summary of the invention

[0003] In order to reduce the compression permanent deformation rate of the rubber material, the present application provides a highly flexible rubber material for a hydraulic pipe and a preparation method thereof.

[0004] In a first aspect, the present application provides a highly flexible rubber material for a hydraulic pipe, which adopts the following technical solution:

[0005] A highly flexible rubber material for hydraulic pipes. The rubber material is mainly made of the following raw materials in parts by weight: 80-90 parts of nitrile rubber, 10-20 parts of chloroprene rubber, 4-6 parts of hyperbranched fluorine-containing polymer, 9-11 parts of dioctyl phthalate, 4-6 parts of zinc oxide, 2-4 parts of magnesium oxide, 1-3 parts of stearic acid, 2-4 parts of sulfur, 1-3 parts of accelerator, 35-45 parts of carbon black, 20-30 parts of white carbon black, 3-5 parts of coupling agent and 2-4 parts of antioxidant; the hyperbranched fluorine-containing polymer is obtained by reacting 2-octenyl succinic anhydride, 3-(2-aminoethylamino)propylamine, diaminobutane, 4,4,4-trifluorobutyric acid and p-aminophenylacetic acid.

[0006] The highly flexible rubber material for hydraulic pipes of the present application has a tensile strength of >17MPa and an elongation at break of >350% through the mutual coordination of raw materials. Moreover, its room temperature compression permanent deformation rate of 23°C × 70h and a compression rate of 30% is <11%, and its high temperature compression permanent deformation rate of 100°C × 70h and a compression rate of 30% is <23%. It exhibits the advantages of high tensile strength, high elongation at break, low compression permanent deformation rate, high resilience and good flexibility, has better comprehensive performance, is suitable for the application of hydraulic pipes, and meets market demand.

[0007] The rubber material of the present application, its rubber matrix is ​​acrylonitrile rubber, chloroprene rubber, and the sum of the two is 100 parts, and fillers are added on this basis, the fillers are carbon black, white carbon black, and the amount of fillers reaches more than 50% of the total weight of the rubber matrix. On this basis, hyperbranched fluoropolymers are added to the raw materials, and 2-octenyl succinic anhydride and 3-(2-aminoethylamino)propylamine are first reacted to obtain intermediate monomers, and then 4-diamine is used as the center, and it is reacted with the intermediate monomer to obtain a hyperbranched polymer, and then 4,4,4-trifluorobutyric acid and p-aminophenylacetic acid are grafted on the surface of the hyperbranched polymer to obtain a hyperbranched fluoropolymer. Hyperbranched fluoropolymers contain a large amount of active groups such as carbon-carbon double bonds, fluorine groups, phenyl groups, and amine groups, and there are also more branched structures. By utilizing hyperbranched fluoropolymers, the compatibility and vulcanization process are increased, the cross-linking density is improved, a tighter and more stable three-dimensional network structure is formed, structural defects are improved, the structural integrity is enhanced, the tensile strength and elongation at break of the rubber material are increased, and the compression permanent deformation rate is reduced, so that the rubber material has excellent flexibility and resilience, can adapt to the complex working environment of the hydraulic pipe, and enhance reliability and safety.

[0008] Optionally, the hyperbranched fluorinated polymer is prepared by the following method:

[0009] T1, mixing 1,4-dioxane and 3-(2-aminoethylamino)propylamine to obtain an organic solution of 3-(2-aminoethylamino)propylamine;

[0010] T2, toluene and 1,4-dioxane are mixed, 2-octenylsuccinic anhydride is added, and an organic solution of 3-(2-aminoethylamino)propylamine is added dropwise. After the addition is complete, the mixture is stirred for 2-4 hours, toluene and 1,4-dioxane are removed by distillation under reduced pressure, and the mixture is dried to constant weight to obtain an intermediate monomer;

[0011] T3. At a temperature of 80-90° C., water and diaminobutane are mixed, the intermediate monomer is added, and the mixture is stirred for 3-5 hours. 4,4,4-trifluorobutyric acid and p-aminophenylacetic acid are added, and the mixture is stirred for 3-5 hours. Water is removed by distillation under reduced pressure, and the mixture is dried to constant weight to obtain a hyperbranched fluorinated polymer.

[0012] Optionally, the weight ratio of the 2-octenylsuccinic anhydride, 3-(2-aminoethylamino)propylamine, diaminobutane, 4,4,4-trifluorobutyric acid and p-aminophenylacetic acid is (9-11):(5-7):(0.1-0.3):(2-4):(1-3).

[0013] In the preparation method of the hyperbranched fluoropolymer of the present application, first in an organic system, the anhydride group in 2-octenyl succinic anhydride reacts with the secondary amine group in 3-(2-aminoethylamino)propylamine to obtain an intermediate monomer, which contains a carbon-carbon double bond, an amino terminal and a carboxyl terminal. Then in an aqueous system, with diaminodiamine as the center, two amino groups in diaminodiamine react with the carboxyl terminal in the intermediate monomer to achieve grafting, obtain a grafted product, not only introduce amino terminals, but also increase the number of branches. Further, the amino terminal in the graft reacts with the carboxyl terminal in the intermediate monomer to achieve grafting and increase the number of branches, and so on to obtain a hyperbranched polymer. The hyperbranched polymer contains a carbon-carbon double bond and an amino terminal. Afterwards, in an aqueous system, the amino terminal in the hyperbranched polymer reacts with the carboxyl in 4,4,4-trifluorobutyric acid and the carboxyl of p-aminophenylacetic acid to achieve grafting, introduce active groups such as fluoro groups and phenyl groups, thereby obtaining a hyperbranched fluoropolymer. The preparation method of the present application not only facilitates the preparation of hyperbranched fluoropolymers, but also better controls the chain growth and branch formation during the reaction process, ensures the stability of the preparation of hyperbranched fluoropolymers, enhances the strength of rubber materials, reduces the compression permanent deformation rate, and improves the overall performance of rubber materials.

[0014] Optionally, the dropwise addition time of the 3-(2-aminoethylamino)propylamine organic solution is 50-70 min.

[0015] The dripping time of the 3-(2-aminoethylamino)propylamine organic solution is limited to ensure that the 3-(2-aminoethylamino)propylamine and 2-octenylsuccinic anhydride react fully, improve the purity and yield of the intermediate monomer, ensure the quality of the hyperbranched fluorine-containing polymer, and enhance the comprehensive performance of the rubber material.

[0016] Optionally, in the method for preparing a hyperbranched fluorine-containing polymer, in step T1, the weight ratio of 1,4-dioxane to 3-(2-aminoethylamino)propylamine is (40-60):(5-7).

[0017] In step T1, the amount of 1,4-dioxane added is optimized to facilitate the dispersion of 3-(2-aminoethylamino)propylamine in 1,4-dioxane. In one embodiment, the weight ratio of 1,4-dioxane to 3-(2-aminoethylamino)propylamine is 50:5, in another embodiment, the weight ratio of 1,4-dioxane to 3-(2-aminoethylamino)propylamine is 50:6, in another embodiment, the weight ratio of 1,4-dioxane to 3-(2-aminoethylamino)propylamine is 50:7, and the weight ratio can be set to 40:5, 40:6, 40:7, 60:5, 60:6, 60:7 as needed, but it is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0018] Optionally, in the method for preparing a hyperbranched fluorinated polymer, in step T2, the weight ratio of toluene, 1,4-dioxane, and 2-octenylsuccinic anhydride is (20-40):(10-30):(9-11).

[0019] In step T2, the addition amounts of toluene and 1,4-dioxane are optimized to facilitate the dispersion of 2-octenylsuccinic anhydride in toluene and 1,4-dioxane, and also to facilitate the full contact and reaction of 2-octenylsuccinic anhydride and 3-(2-aminoethylamino)propylamine. In one embodiment, the weight ratio of toluene, 1,4-dioxane and 2-octenyl succinic anhydride is 30:20:9. In another embodiment, the weight ratio of toluene, 1,4-dioxane and 2-octenyl succinic anhydride is 3:2:1. In another embodiment, the weight ratio of toluene, 1,4-dioxane and 2-octenyl succinic anhydride is 30:20:11. The weight ratio can be set to 20:10:9, 20:10:11, 20:30:9, 20:30:11, 40:10:9, 40:10:11, 40:30:9, 40:30:11 as needed, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0020] Optionally, in the method for preparing a hyperbranched fluorinated polymer, in step T3, the weight ratio of water to diamine is (80-120):(0.1-0.3).

[0021] In step T3, the amount of water added is optimized to facilitate the full contact and reaction of diaminobenzene, intermediate monomer, 4,4,4-trifluorobutyric acid, and p-aminophenylacetic acid. In one embodiment, the weight ratio of water to diaminobenzene is 100:0.1, in another embodiment, the weight ratio of water to diaminobenzene is 100:0.2, and in another embodiment, the weight ratio of water to diaminobenzene is 100:0.3. The weight ratio can be set to 80:0.1, 80:0.2, 80:0.3, 120:0.1, 120:0.2, 120:0.3 as needed, but it is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0022] Optionally, the average particle size of the carbon black is 100-300 μm, and the average particle size of the white carbon black is 100-300 μm.

[0023] The average particle size of carbon black and the average particle size of white carbon black are limited so that the carbon black and white carbon black are evenly dispersed in the rubber material, thereby reducing internal stress concentration, improving the strength and durability of the rubber material, and extending the service life, making it suitable for the application of hydraulic pipes.

[0024] In multiple embodiments, the average particle size of carbon black is 150 μm, which can be set to 100 μm, 130 μm, 180 μm, 200 μm, 230 μm, 250 μm, 280 μm, 300 μm as needed, but 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, which can be set to 100 μm, 130 μm, 180 μm, 200 μm, 230 μm, 250 μm, 280 μm, 300 μm as needed, but is not limited to the listed values, and other values ​​not listed in the numerical range are also applicable.

[0025] Optionally, the iodine absorption value of the carbon black is 70-100 g / kg, and the BET specific surface area of ​​the white carbon black is 70-130 m 2 / g.

[0026] The iodine absorption value of carbon black and the BET specific surface area of ​​white carbon black are limited to ensure the stability of the sources of carbon black and white carbon black, and also to ensure the quality of rubber materials. In multiple implementation schemes, the iodine absorption value of carbon black is 82g / kg, and the iodine absorption value can be set to 70g / kg, 75g / kg, 80g / kg, 85g / kg, 90g / kg, 95g / kg, 100g / kg 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 implementation schemes, the BET specific surface area of ​​white carbon black is 90m 2 / g, the BET specific surface area can be set to 70m 2 / g, 75m 2 / g, 80m 2 / g, 85m 2 / g, 95m 2 / g、100m 2 / g、105m 2 / g, 110m 2 / g, 115m 2 / g, 120m 2 / g, 125m 2 / g, 130m 2 / g, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0027] Optionally, the mass content of acrylonitrile in the nitrile rubber is 30-40%, and the Mooney viscosity ML (1+4, 100°C) is 40-60; the mass content of chlorine in the chloroprene rubber is 30-40%, and the Mooney viscosity ML (1+4, 100°C) is 40-60.

[0028] The acrylonitrile content and Mooney viscosity of the nitrile rubber are limited, and the chlorine content and Mooney viscosity of the chloroprene rubber are also limited to ensure the stability of the sources of the nitrile rubber and the chloroprene rubber, and also to ensure the quality of the rubber material. In multiple embodiments, the acrylonitrile mass content in the nitrile rubber is 33%, and the Mooney viscosity ML (1+4, 100°C) is 52. The acrylonitrile mass content can be set to 30%, 35%, 37%, and 40% as needed. The Mooney viscosity ML (1+4, 100°C) can also be set to 40, 45, 50, 55, and 60 as needed, but it is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable. In multiple embodiments, the chlorine mass content in the chloroprene rubber is 36%, and the Mooney viscosity ML (1+4, 100°C) is 55. The chlorine mass content can be set to 30%, 32%, 35%, 37%, or 40% as needed, and the Mooney viscosity ML (1+4, 100°C) can also be set to 40, 45, 50, or 60 as needed, but is not limited to the listed values, and other unlisted values ​​within the numerical range are equally applicable.

[0029] Optionally, the coupling agent is one or more of coupling agent KH560, coupling agent KH570, coupling agent KH580, and coupling agent KH792.

[0030] Further limiting the coupling agent not only facilitates the selection of the coupling agent, but also coupling agent KH560, coupling agent KH570, coupling agent KH580, and coupling agent KH792 can improve the interfacial bonding strength of the rubber material, enhance the interaction between carbon black, white carbon black and raw materials, reduce interface defects, and improve the mechanical properties and aging resistance of the rubber material.

[0031] Optionally, the accelerator is one or more of accelerator MBTS, accelerator NOBS, accelerator DETU, and accelerator CZ.

[0032] Further limiting the accelerator not only facilitates the selection of the accelerator, but also accelerator MBTS, accelerator NOBS, accelerator DETU, and accelerator CZ can significantly promote the vulcanization reaction, shorten the vulcanization time, improve the vulcanization efficiency and vulcanization quality of the rubber material, and make the rubber material have better strength, resilience and heat resistance.

[0033] Optionally, the antioxidant is one or more of antioxidant 4020, antioxidant 4010, antioxidant 445, antioxidant 264, antioxidant AW, and antioxidant SP.

[0034] Further limiting the antioxidant not only facilitates the selection of the antioxidant, but also antioxidant 4020, antioxidant 4010, antioxidant 445, antioxidant 264, antioxidant AW and antioxidant SP can effectively inhibit the aging of rubber materials due to oxidation or thermal degradation during use, reduce the influence of the external environment on the rubber materials, and ensure the reliability, safety and life of the rubber materials.

[0035] In a second aspect, the present application provides a method for preparing a highly flexible rubber material for a hydraulic pipe, which adopts the following technical solution:

[0036] A method for preparing a highly flexible rubber material for a hydraulic pipe mainly comprises the following steps:

[0037] S1, mixing nitrile rubber, chloroprene rubber, magnesium oxide, and antioxidant for 3-5 minutes, adding stearic acid and dioctyl phthalate, mixing for 3-5 minutes, adding carbon black, white carbon black, and coupling agent, mixing for 8-12 minutes, adding hyperbranched fluorinated polymer, zinc oxide, sulfur, and accelerator, mixing for 4-6 minutes, taking out, and standing at room temperature for 22-26 hours to obtain a mixed rubber;

[0038] S2. vulcanizing the rubber mixture to obtain a rubber material.

[0039] Optionally, in step S2, the vulcanization temperature is 150-160°C, the pressure is 6-10 MPa, and the time is 50-70 min.

[0040] Optimizing the vulcanization temperature, pressure and time can effectively promote the cross-linking reaction between the raw materials, improve the mechanical strength and heat resistance of the rubber material, and help improve the uniformity and density of the internal structure of the rubber material, so that the rubber material can maintain high flexibility while enhancing the overall performance and extending the service life.

[0041] In multiple embodiments, the vulcanization temperature is 155°C, the pressure is 8 MPa, and the time is 60 min. The temperature can be set to 150°C, 152°C, 157°C, or 160°C as needed. The pressure can also be set to 6MPa, 7MPa, 9MPa, or 10MPa as needed. The time can also be set to 50min, 55min, 65min, or 70min as needed. However, the process is not limited to the listed values, and other values ​​not listed within the numerical range are equally applicable.

[0042] In summary, this application has at least the following beneficial effects:

[0043] The highly flexible rubber material for hydraulic pipe of the present application is prepared by adding a hyperbranched fluorine-containing polymer to the raw material of the rubber material, wherein the hyperbranched fluorine-containing polymer contains a large number of active groups such as carbon-carbon double bonds, fluorine groups, phenyl groups, amine groups, and a large number of branched structures. The hyperbranched fluorine-containing polymer and the raw material cooperate with each other to increase compatibility and cross-linking density, form a tighter and more stable three-dimensional network structure, reduce structural defects, and improve integrity, so that the tensile strength of the rubber material is greater than 17MPa, and the elongation at break is greater than 350%. Moreover, the room temperature compression permanent deformation rate of the rubber material at 23°C×70h and a compression rate of 30% is less than 11%, and the high temperature compression permanent deformation rate of the rubber material at 100°C×70h and a compression rate of 30% is less than 23%. The rubber material exhibits the advantages of high tensile strength, high elongation at break, low compression permanent deformation rate, high resilience, and good flexibility, and can adapt to the complex working environment of the hydraulic pipe, enhance reliability and safety, and meet market demand. DETAILED DESCRIPTION

[0044] 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.

[0045] Preparation Example

[0046] Preparation Example 1

[0047] A hyperbranched fluorine-containing polymer is prepared by the following method:

[0048] T1. Add 6 g of 3-(2-aminoethylamino)propylamine to 50 g of 1,4-dioxane at a rotation speed of 500 r / min, and stir for 5 min to obtain an organic solution of 3-(2-aminoethylamino)propylamine.

[0049] T2. Add 20 g of 1,4-dioxane to 30 g of toluene at a speed of 2000 r / min and stir for 3 min. Add 10 g of 2-octenylsuccinic anhydride and stir for 5 min. Add the 3-(2-aminoethylamino)propylamine organic solution obtained in step T1 dropwise. The 3-(2-aminoethylamino)propylamine organic solution is added dropwise within 60 min. After the addition is complete, stir for 3 h. Remove toluene and 1,4-dioxane by vacuum distillation and dry to constant weight to obtain the intermediate monomer.

[0050] T3, at a speed of 500 r / min and a temperature of 85°C, add 0.2 g of diaminobutane to 100 g of water and stir for 5 min. Add the intermediate monomer obtained in step T2 and stir for 4 h. Add 3.2 g of 4,4,4-trifluorobutyric acid and 1.7 g of p-aminophenylacetic acid and stir for 4 h. Remove water by vacuum distillation and dry to constant weight to obtain a hyperbranched fluorinated polymer.

[0051] Preparation Example 2

[0052] A hyperbranched fluorine-containing polymer is prepared by the following method:

[0053] T1. Add 5 g of 3-(2-aminoethylamino)propylamine to 50 g of 1,4-dioxane at a rotation speed of 500 r / min, and stir for 5 min to obtain an organic solution of 3-(2-aminoethylamino)propylamine.

[0054] T2. Add 20 g of 1,4-dioxane to 30 g of toluene at a speed of 2000 r / min and stir for 3 min. Add 9 g of 2-octenylsuccinic anhydride and stir for 5 min. Add the 3-(2-aminoethylamino)propylamine organic solution obtained in step T1 dropwise. The 3-(2-aminoethylamino)propylamine organic solution is added dropwise within 50 min. After the addition is complete, stir for 2 h. Remove toluene and 1,4-dioxane by vacuum distillation and dry to constant weight to obtain the intermediate monomer.

[0055] T3, at a speed of 500 r / min and a temperature of 80°C, add 0.3 g of diaminobutane to 100 g of water and stir for 5 min. Add the intermediate monomer obtained in step T2 and stir for 3 h. Add 2 g of 4,4,4-trifluorobutyric acid and 3 g of p-aminophenylacetic acid and stir for 5 h. Remove water by vacuum distillation and dry to constant weight to obtain a hyperbranched fluorinated polymer.

[0056] Preparation Example 3

[0057] A hyperbranched fluorine-containing polymer is prepared by the following method:

[0058] T1. Add 7 g of 3-(2-aminoethylamino)propylamine to 50 g of 1,4-dioxane at a rotation speed of 500 r / min, and stir for 5 min to obtain an organic solution of 3-(2-aminoethylamino)propylamine.

[0059] T2. Add 20 g of 1,4-dioxane to 30 g of toluene at a speed of 2000 r / min and stir for 3 min. Add 10 g of 2-octenylsuccinic anhydride and stir for 5 min. Add the 3-(2-aminoethylamino)propylamine organic solution obtained in step T1 dropwise. The 3-(2-aminoethylamino)propylamine organic solution was added dropwise within 70 min. After the addition was completed, stir for 4 h. Remove toluene and 1,4-dioxane by vacuum distillation and dry to constant weight to obtain the intermediate monomer.

[0060] T3, at a speed of 500 r / min and a temperature of 90°C, add 0.1 g of diaminobutane to 100 g of water and stir for 5 min. Add the intermediate monomer obtained in step T2 and stir for 5 h. Add 4 g of 4,4,4-trifluorobutyric acid and 1 g of p-aminophenylacetic acid and stir for 3 h. Remove water by vacuum distillation and dry to constant weight to obtain a hyperbranched fluorinated polymer. Example

[0061] Table 1 Amount of each raw material used in rubber materials (unit: ×10g)

[0062] Example 1

[0063] A highly flexible rubber material for hydraulic pipes, the raw materials and raw material ratios of which are shown in Table 1.

[0064] Among them, the mass content of acrylonitrile in nitrile rubber is 33%, and the Mooney viscosity ML (1+4, 100℃) is 52; the mass content of chlorine in chloroprene rubber is 36%, and the Mooney viscosity ML (1+4, 100℃) is 55; the accelerator is accelerator MBTS; the average particle size of carbon black is 150μm, and the iodine absorption value is 82g / kg; the average particle size of white carbon black is 150μm, and the BET specific surface area is 90m 2 / g; the coupling agent is coupling agent KH560; the antioxidant is antioxidant 4020; the hyperbranched fluorine-containing polymer is prepared by the method of Preparation Example 1.

[0065] A method for preparing a highly flexible rubber material for a hydraulic pipe mainly comprises the following steps:

[0066] S1. Use a mixer to add chloroprene rubber, magnesium oxide, and antioxidant to nitrile rubber, and mix for 4 minutes. Add stearic acid and dioctyl phthalate, and mix for 4 minutes. Add carbon black, white carbon black, and coupling agent, and mix for 10 minutes. Add hyperbranched fluorinated polymer, zinc oxide, sulfur, and accelerator, and mix for 5 minutes. Take out, stand at 23°C for 24 hours, and obtain a mixed rubber.

[0067] S2. vulcanizing the mixed rubber with a vulcanizing machine to obtain a rubber material.

[0068] The vulcanization temperature is 155°C, the pressure is 8 MPa, and the time is 60 min. Example 2

[0069] A highly flexible rubber material for hydraulic pipes, which differs from Example 1 in that the raw material ratio of the rubber material is different, and the raw material ratio is shown in Table 1. Example 3

[0070] A highly flexible rubber material for hydraulic pipes, which differs from Example 1 in that the raw material ratio of the rubber material is different, and the raw material ratio is shown in Table 1. Example 4

[0071] A highly flexible rubber material for hydraulic pipes, which differs from Example 1 in that the source of the hyperbranched fluoropolymer in the raw materials of the rubber material is different, and the hyperbranched fluoropolymer is prepared by the method of Preparation Example 2. Example 5

[0072] A highly flexible rubber material for hydraulic pipes, which differs from Example 1 in that the source of the hyperbranched fluorine-containing polymer in the raw materials of the rubber material is different, and the hyperbranched fluorine-containing polymer is prepared by the method of Preparation Example 3.

[0073] Comparative Example

[0074] Comparative Example 1

[0075] A highly flexible rubber material for hydraulic pipes, which differs from Example 1 in that no hyperbranched fluorine-containing polymer is added to the raw materials of the rubber material.

[0076] Comparative Example 2

[0077] A highly flexible rubber material for hydraulic pipes, which differs from Example 1 in that an equal amount of hyperbranched polymer is used to replace a hyperbranched fluorine-containing polymer in the raw materials of the rubber material.

[0078] The hyperbranched polymer is prepared by the following method:

[0079] T1. Add 6 g of 3-(2-aminoethylamino)propylamine to 50 g of 1,4-dioxane at a rotation speed of 500 r / min, and stir for 5 min to obtain an organic solution of 3-(2-aminoethylamino)propylamine.

[0080] T2. Add 20 g of 1,4-dioxane to 30 g of toluene at a speed of 2000 r / min and stir for 3 min. Add 10 g of 2-octenylsuccinic anhydride and stir for 5 min. Add the 3-(2-aminoethylamino)propylamine organic solution obtained in step T1 dropwise. The 3-(2-aminoethylamino)propylamine organic solution is added dropwise within 60 min. After the addition is complete, stir for 3 h. Remove toluene and 1,4-dioxane by vacuum distillation and dry to constant weight to obtain the intermediate monomer.

[0081] T3. Add 0.2 g of diaminobutane to 100 g of water at a speed of 500 r / min and a temperature of 85°C, and stir for 5 min. Add the intermediate monomer obtained in step T2, and stir for 4 h. Add 4.9 g of water, and stir for 4 h. Remove water by vacuum distillation, and dry to constant weight to obtain a hyperbranched fluorine-containing polymer.

[0082] Comparative Example 3

[0083] A highly flexible rubber material for hydraulic pipes, which differs from Example 1 in that, in the raw materials of the rubber material, in the preparation method of the hyperbranched fluorine-containing polymer, an equal amount of 4,4,4-trifluorobutyric acid is used to replace p-aminophenylacetic acid.

[0084] Comparative Example 4

[0085] A highly flexible rubber material for hydraulic pipes, which differs from Example 1 in that, in the raw materials of the rubber material, in the preparation method of the hyperbranched fluorine-containing polymer, an equal amount of p-aminophenylacetic acid is used to replace 4,4,4-trifluorobutyric acid.

[0086] Performance Testing

[0087] The rubber materials obtained in Examples 1-5 and Comparative Examples 1-4 were respectively taken and the following performance tests were performed on the rubber materials. The test results are shown in Table 2.

[0088] Among them, according to GB / T528-2009 "Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber", the tensile strength and elongation at break of rubber materials are tested.

[0089] According to GB / T7759.1-2015 "Determination of compression set of vulcanized rubber or thermoplastic rubber Part 1: At room temperature and high temperature conditions", the compression set rate of rubber materials is tested.

[0090] Moreover, the conditions for the room temperature compression permanent deformation rate are: 23°C×70h, compression rate 30%; the conditions for the high temperature compression permanent deformation rate are: 100°C×70h, compression rate 30%.

[0091] Table 2 Test results

[0092]

[0093] As can be seen from Table 2, the rubber material of the present application has high tensile strength and elongation at break, with a tensile strength of 17.31-18.63MPa and an elongation at break of 360-385%, showing the advantages of high tensile strength and high elongation at break, and it also has a low compression permanent deformation rate, 23℃×70h, 30% compression permanent deformation rate at room temperature is 9.31-10.14%, 100℃×70h, 30% compression permanent deformation rate at high temperature is 20.63-22.28%, showing the advantage of low compression permanent deformation rate. The rubber material of the present application, through the mutual cooperation between the raw materials, has the advantages of high tensile strength, high elongation at break, low compression permanent deformation rate, high resilience, and good flexibility, showing good comprehensive performance and meeting market demand.

[0094] Comparative Examples 1-2 are compared, and Comparative Example 1 is used as the basis. Comparative Example 2 is compared to Comparative Example 1, and a hyperbranched polymer is added to the raw material of the rubber material, and 2-octenyl succinic anhydride, 3-(2-aminoethylamino) propylamine, and diamine are used to react to obtain. It can be seen from this that adding a hyperbranched polymer in the raw material of the rubber material is conducive to improving tensile strength and reducing compression set. In conjunction with Example 1, Example 1 is compared to Comparative Example 1, and a hyperbranched fluorinated polymer is added to the raw material of the rubber material, and 2-octenyl succinic anhydride, 3-(2-aminoethylamino) propylamine, diamine, 4,4,4-trifluorobutyric acid, and p-aminophenylacetic acid are used to react to obtain. It can be seen from this that on the basis of adding a hyperbranched polymer in the raw material of the rubber material, further modification treatment is carried out, which can effectively improve the interaction between the hyperbranched polymer and the raw material, enhance the stability of the network structure, improve tensile strength and elongation at break, and reduce compression set.

[0095] Comparative Examples 2-4 and Example 1 are compared, and Comparative Example 2 is used as the basis. Compared with Comparative Example 2, Comparative Example 3 grafts 4,4,4-trifluorobutyric acid on the surface of the hyperbranched polymer. Compared with Comparative Example 2, Comparative Example 4 grafts p-aminophenylacetic acid on the surface of the hyperbranched polymer; Compared with Comparative Example 2, Example 1 grafts 4,4,4-trifluorobutyric acid and p-aminophenylacetic acid on the surface of the hyperbranched polymer. It can be seen that by simultaneously grafting 4,4,4-trifluorobutyric acid and p-aminophenylacetic acid on the surface of the hyperbranched polymer, and introducing active groups such as fluorine, phenyl, and amine groups, the compatibility, dispersibility, and bonding strength of the hyperbranched fluorinated polymer can be further enhanced, the crosslinking density and the stability of the network structure can be enhanced, the tensile strength can be further improved, and the compression permanent deformation rate can be further reduced, so that the rubber material exhibits better comprehensive performance.

[0096] 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. A highly flexible rubber material for hydraulic pipe, characterized in that: The rubber material is mainly made of the following raw materials in parts by weight: 80-90 parts of nitrile rubber, 10-20 parts of chloroprene rubber, 4-6 parts of hyperbranched fluorine-containing polymer, 9-11 parts of dioctyl phthalate, 4-6 parts of zinc oxide, 2-4 parts of magnesium oxide, 1-3 parts of stearic acid, 2-4 parts of sulfur, 1-3 parts of accelerator, 35-45 parts of carbon black, 20-30 parts of white carbon black, 3-5 parts of coupling agent, and 2-4 parts of antioxidant; the hyperbranched fluorine-containing polymer is obtained by reacting 2-octenyl succinic anhydride, 3-(2-aminoethylamino)propylamine, diaminobutane, 4,4,4-trifluorobutyric acid, and p-aminophenylacetic acid; The hyperbranched fluorine-containing polymer is prepared by the following method: T1, mixing 1,4-dioxane and 3-(2-aminoethylamino)propylamine to obtain an organic solution of 3-(2-aminoethylamino)propylamine; T2, toluene and 1,4-dioxane are mixed, 2-octenylsuccinic anhydride is added, and an organic solution of 3-(2-aminoethylamino)propylamine is added dropwise. After the addition is complete, the mixture is stirred for 2-4 hours, toluene and 1,4-dioxane are removed by distillation under reduced pressure, and the mixture is dried to constant weight to obtain an intermediate monomer; T3, at a temperature of 80-90° C., water and diaminobutane were mixed, the intermediate monomer was added, the mixture was stirred for 3-5 hours, 4,4,4-trifluorobutyric acid and p-aminophenylacetic acid were added, the mixture was stirred for 3-5 hours, water was removed by distillation under reduced pressure, and the mixture was dried to constant weight to obtain a hyperbranched fluorinated polymer; The weight ratio of the 2-octenylsuccinic anhydride, 3-(2-aminoethylamino)propylamine, diaminobutane, 4,4,4-trifluorobutyric acid and p-aminophenylacetic acid is (9-11):(5-7):(0.1-0.3):(2-4):(1-3).

2. The highly flexible rubber material for hydraulic pipe according to claim 1, characterized in that: The dropping time of the 3-(2-aminoethylamino)propylamine organic solution is 50-70 minutes.

3. The highly flexible rubber material for hydraulic pipe according to claim 1, characterized in that: The average particle size of the carbon black is 100-300 μm, and the average particle size of the white carbon black is 100-300 μm.

4. The highly flexible rubber material for hydraulic pipe according to claim 1, characterized in that: The coupling agent is one or more of coupling agent KH560, coupling agent KH570, coupling agent KH580, and coupling agent KH792.

5. The highly flexible rubber material for hydraulic pipe according to claim 1, characterized in that: The accelerator is one or more of accelerator MBTS, accelerator NOBS, accelerator DETU and accelerator CZ.

6. The highly flexible rubber material for hydraulic pipe according to claim 1, characterized in that: The antioxidant is one or more of antioxidant 4020, antioxidant 4010, antioxidant 445, antioxidant 264, antioxidant AW, and antioxidant SP.

7. A method for preparing a highly flexible rubber material for hydraulic pipe according to any one of claims 1 to 6, characterized in that: The main steps are as follows: S1, mixing nitrile rubber, chloroprene rubber, magnesium oxide, and antioxidant for 3-5 minutes, adding stearic acid and dioctyl phthalate, mixing for 3-5 minutes, adding carbon black, white carbon black, and coupling agent, mixing for 8-12 minutes, adding hyperbranched fluorinated polymer, zinc oxide, sulfur, and accelerator, mixing for 4-6 minutes, taking out, and standing at room temperature for 22-26 hours to obtain a mixed rubber; S2. vulcanizing the rubber mixture to obtain a rubber material.

8. The method for preparing a highly flexible rubber material for hydraulic pipe according to claim 7, characterized in that: In step S2, the vulcanization temperature is 150-160°C, the pressure is 6-10 MPa, and the time is 50-70 min.

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