Corrosion-resistant oil-resistant PU air pipe and preparation method thereof

Abstract

The invention relates to the technical field of PU gas pipes, in particular to a corrosion-resistant and oil-resistant PU gas pipe and a preparation method thereof, and aims to solve the problems that an existing PU gas pipe is insufficient in corrosion resistance and oil resistance, and the normal service life and the working reliability of the existing PU gas pipe are seriously influenced when the existing PU gas pipe is in a corrosive environment for a long time and is in contact with oil substances. According to the PU air pipe, polyurethane resin and ethylene propylene diene monomer serve as main raw materials to prepare the PU air pipe, the PU air pipe has good flexibility, after a polyfluorotriazine ring modifier and a polyfluorographene modifier are added into the PU air pipe, the mechanical property of the PU air pipe can be improved, the resistance of the PU air pipe to corrosive media and oily substances is remarkably improved, and the service life of the PU air pipe is prolonged. The PU air pipe can still keep good transmission performance and mechanical performance under the complex environment of acid, alkali and oil stains, so that the service life of the PU air pipe is greatly prolonged, and the maintenance cost and the replacement frequency are reduced. And the service life is prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of PU air pipes, and particularly relates to a corrosion-resistant and oil-resistant PU air pipe and a preparation method thereof. Background Art

[0002] PU air pipes, namely PU pipes, are widely used in multiple fields such as pneumatic control, industrial fluid transportation, agricultural irrigation, food processing, medical equipment, and civil engineering due to their excellent flexibility. However, the existing PU air pipes have deficiencies in terms of corrosion resistance and oil resistance. Especially when in a corrosive environment for a long time and after contacting oil substances, the performance of the PU air pipes drops significantly, thus affecting their normal service life and working reliability.

[0003] Therefore, it is of great significance to develop a corrosion-resistant and oil-resistant PU air pipe and a preparation method thereof. Summary of the Invention

[0004] In order to overcome the above technical problems, the purpose of the present invention is to provide a corrosion-resistant and oil-resistant PU air pipe and a preparation method thereof, which solves the problems that the existing PU air pipes have deficiencies in terms of corrosion resistance and oil resistance, and seriously affect their normal service life and working reliability when in a corrosive environment for a long time and after contacting oil substances.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] A corrosion-resistant and oil-resistant PU air pipe, comprising the following components in parts by weight:

[0007] 70 - 80 parts of polyurethane resin, 22 - 34 parts of ethylene propylene diene monomer rubber, 3 - 11 parts of polyfluorotriazine ring modifier, 0.3 - 1.7 parts of polyfluorographene modifier, 8 - 14 parts of carbon black, 3 - 7 parts of talcum powder, 0.8 - 2.2 parts of zinc stearate, 0.2 - 0.4 parts of 2-mercaptobenzothiazole, 2 - 6 parts of dibutyl phthalate, 0.1 - 0.3 parts of 2,6-di-tert-butyl-p-cresol, and 0.1 - 0.3 parts of N-cyclohexyl-N'-phenyl-p-phenylenediamine;

[0008] Among them, the polyfluorotriazine ring modifier is prepared by the following steps:

[0009] Step a1: Add cyanuric chloride, hexafluoroisopropanol, and anhydrous acetonitrile into a three-necked flask equipped with a stirrer, a thermometer, and a gas pipe, introduce nitrogen for protection, and then stir and react at a temperature of 0 - 5°C and a stirring rate of 300 - 400 r / min for 1 - 2 h. Then, continue to stir and react at a temperature of 50 - 55°C for 2 - 3 h. After the reaction ends, cool the reaction product to room temperature, and then rotate and evaporate to remove the solvent to obtain a disubstituted fluorinated intermediate;

[0010] Step a2: Add the disubstituted fluorinated intermediate, trimethylolpropane, anhydrous potassium carbonate, and N,N-dimethylformamide into a three-necked flask equipped with a stirrer, a thermometer, and a gas pipe. Introduce nitrogen for protection. Then, stir and react at a temperature of 95 - 100 °C and a stirring rate of 300 - 400 r / min for 8 - 10 h. After the reaction ends, cool the reaction product to room temperature, then perform vacuum filtration. Rotate evaporate the filtrate to remove the solvent. Then, wash it 2 - 3 times successively with anhydrous acetone, anhydrous ethanol, and distilled water. Then, place it in a vacuum drying oven and dry it at a temperature of 60 - 65 °C for 2 - 3 h to obtain the polyfluorotriazine ring modifier.

[0011] As a further scheme of the present invention: The dosage ratio of cyanuric chloride, hexafluoroisopropanol, and anhydrous acetonitrile in step a1 is 10 mmol: 22 - 26 mmol: 50 - 60 mL.

[0012] As a further scheme of the present invention: The dosage ratio of the disubstituted fluorinated intermediate, trimethylolpropane, anhydrous potassium carbonate, and N,N-dimethylformamide in step a2 is 33 - 36 mmol: 10 mmol: 40 - 45 mmol: 80 - 100 mL.

[0013] As a further scheme of the present invention: The polyfluorographene modifier is prepared by the following steps:

[0014] Step b1: Add graphite powder, concentrated sulfuric acid, and concentrated nitric acid into a three-necked flask equipped with a stirrer, a thermometer, and a gas pipe. Introduce nitrogen for protection. Stir and react at a temperature of 25 - 30 °C and a stirring rate of 300 - 400 r / min for 5 - 10 min. Then, add potassium permanganate and continue to stir and react at a temperature of 50 - 55 °C for 3 - 5 h. Then, continue to stir and react at a temperature of 90 - 100 °C for 3 - 5 h. After the reaction ends, cool the reaction product to room temperature, then pour it into a hydrogen peroxide solution at a temperature of 0 - 5 °C. Then, centrifuge it. Wash the precipitate 3 - 5 times successively with hydrochloric acid solution and distilled water. Then, place it in a vacuum drying oven and dry it at a temperature of 50 - 55 °C for 4 - 5 h to obtain graphene oxide;

[0015] Step b2: Add graphene oxide and ethanol solution into a three-necked flask equipped with a stirrer, a thermometer and a gas guide tube, introduce nitrogen for protection, stir and react for 5 - 10 min under the conditions of a temperature of 25 - 30 °C and a stirring rate of 300 - 400 r / min. Then add 3-aminopropyltrimethoxysilane and continue to stir and react for 15 - 20 h under the condition of heating to 60 - 65 °C. After the reaction is completed, cool the reaction product to room temperature, then centrifuge, wash the precipitate with absolute ethanol 3 - 5 times, and then place it in a vacuum drying oven and dry it for 4 - 5 h under the condition of a temperature of 50 - 55 °C to obtain amino-functionalized graphene oxide;

[0016] Step b3: Add amino-functionalized graphene oxide, triethylamine and dichloromethane into a three-necked flask equipped with a stirrer, a thermometer and a constant pressure dropping funnel, ultrasonically disperse for 20 - 30 min under the condition of an ultrasonic power of 250 - 350 W, and then stir and react for 10 - 20 min under the conditions of a temperature of 25 - 30 °C and a stirring rate of 300 - 400 r / min. Then, while stirring, gradually add perfluorobutanesulfonyl fluoride-dichloromethane solution drop by drop, control the dropping rate to be 1 - 2 drops / s. After the dropping is completed, heat up to 45 - 50 °C and continue to stir and react for 4 - 6 h. After the reaction is completed, cool the reaction product to room temperature, then centrifuge, wash the precipitate with anhydrous acetone 3 - 5 times, and then place it in a vacuum drying oven and dry it for 4 - 5 h under the condition of a temperature of 50 - 55 °C to obtain a polyfluorinated graphene modifier.

[0017] As a further scheme of the present invention: The dosage ratio of the graphite powder, concentrated sulfuric acid, concentrated nitric acid, potassium permanganate and hydrogen peroxide solution in step b1 is 1 g : 35 - 40 mL : 11 - 13 mL : 6 - 8 g : 50 - 60 mL.

[0018] As a further scheme of the present invention: The mass fraction of the concentrated sulfuric acid in step b1 is 96 - 98%, the mass fraction of the concentrated nitric acid is 66 - 68%, the mass fraction of the hydrogen peroxide solution is 1 - 2%, and the mass fraction of the hydrochloric acid solution is 3 - 5%.

[0019] As a further scheme of the present invention: The dosage ratio of the graphene oxide, ethanol solution and 3-aminopropyltrimethoxysilane in step b2 is 1 g : 35 - 40 mL : 1 - 5 mL.

[0020] As a further scheme of the present invention: The volume fraction of the ethanol solution in step b2 is 85 - 90%.

[0021] As a further solution of the present invention: the dosage ratio of the amino-functionalized graphene oxide, triethylamine, dichloromethane, and perfluorobutanesulfonyl fluoride-dichloromethane solution in step b3 is 1 g: 2 - 3 mL: 40 - 50 mL: 10 - 15 mL.

[0022] As a further solution of the present invention: the perfluorobutanesulfonyl fluoride-dichloromethane solution in step b3 is a solution formed by dissolving perfluorobutanesulfonyl fluoride in dichloromethane according to 0.8 - 1.6 g: 10 mL.

[0023] As a further solution of the present invention: a preparation method of a corrosion-resistant and oil-resistant PU air tube, comprising the following steps:

[0024] Step 1: Weigh 70 - 80 parts by weight of polyurethane resin, 22 - 34 parts of ethylene propylene diene monomer rubber, 3 - 11 parts of polyfluorotriazine ring modifier, 0.3 - 1.7 parts of polyfluorographene modifier, 8 - 14 parts of carbon black, 3 - 7 parts of talcum powder, 0.8 - 2.2 parts of zinc stearate, 0.2 - 0.4 parts of 2-mercaptobenzothiazole, 2 - 6 parts of dibutyl phthalate, 0.1 - 0.3 parts of 2,6-di-tert-butyl-p-cresol, and 0.1 - 0.3 parts of N-cyclohexyl-N'-phenyl-p-phenylenediamine, and set aside; the polyurethane resin is Wanhua TPU WHT-8185RV; the ethylene propylene diene monomer rubber is Dow IP4640L ethylene propylene diene monomer rubber from the United States;

[0025] Step 2: Mix the polyurethane resin, ethylene propylene diene monomer rubber, polyfluorotriazine ring modifier, polyfluorographene modifier, carbon black, talcum powder, zinc stearate, 2-mercaptobenzothiazole, dibutyl phthalate, 2,6-di-tert-butyl-p-cresol, and N-cyclohexyl-N'-phenyl-p-phenylenediamine evenly, and then extrude them through an extruder by melting, and cool and shape them to obtain a corrosion-resistant and oil-resistant PU air tube.

[0026] The beneficial effects of the present invention:

[0027] A corrosion-resistant and oil-resistant PU air tube of the present invention and its preparation method. By uniformly mixing polyurethane resin, ethylene propylene diene monomer rubber, polyfluorotriazine ring modifier, polyfluorographene modifier, carbon black, talcum powder, zinc stearate, 2-mercaptobenzothiazole, dibutyl phthalate, 2,6-di-tert-butyl-p-cresol, and N-cyclohexyl-N'-phenyl-p-phenylenediamine, and then melt-extruding through an extruder and cooling and shaping, a corrosion-resistant and oil-resistant PU air tube is obtained; this PU air tube is prepared with polyurethane resin and ethylene propylene diene monomer rubber as the main raw materials to make it have good flexibility. After adding polyfluorotriazine ring modifier and polyfluorographene modifier, its mechanical properties can be improved, and the resistance of the PU air tube to corrosive media and oily substances is significantly enhanced, enabling it to maintain good transmission performance and mechanical properties in a complex environment of acid, alkali, and oil stains, thus greatly extending the service life of the PU air tube, reducing maintenance costs and replacement frequencies. The service life is extended.

[0028] During the preparation of the corrosion-resistant and oil-resistant PU air tube, a polyfluorotriazine ring modifier was first prepared. First, cyanuric chloride and hexafluoroisopropanol were reacted. The cyanuric chloride molecule has three active chlorine atoms: the primary chlorine atom can react at 0-5°C, the secondary chlorine atom can react at 40-60°C, and the tertiary chlorine atom can react at 90-100°C. Therefore, two chlorine atoms on the cyanuric chloride were controlled to react with the hydroxyl groups on the hexafluoroisopropanol to obtain a disubstituted fluorinated intermediate. Then, the disubstituted fluorinated intermediate and trimethylolpropane were reacted, and the remaining one chlorine atom on the disubstituted fluorinated intermediate reacted with the hydroxyl group on the trimethylolpropane to obtain the polyfluorotriazine ring modifier; the fluorine atoms in this polyfluorotriazine ring modifier have extremely strong electronegativity and a small atomic radius, which enables the fluorine atoms to closely surround the triazine ring structure to form a dense fluorinated layer. This fluorinated layer can not only effectively block the penetration of corrosive media and oily substances, but also the triazine ring forms hydrogen bonds with the PU molecular chain to enhance the interfacial bonding. In addition, the triazine ring structure itself has high rigidity and stability, which can enhance the intermolecular interaction force between the molecular chains of the PU matrix, thereby improving the overall strength of the material.

[0029] In the process of preparing the corrosion-resistant and oil-resistant PU air pipe, a polyfluorinated graphene modifier was also prepared. Graphene oxide was prepared using graphite powder as the raw material. Then, 3-aminopropyltrimethoxysilane was used to modify the surface of graphene oxide to improve its dispersibility and avoid its agglomeration, while introducing a large number of amino groups to obtain amino-functionalized graphene oxide. Subsequently, amino-functionalized graphene oxide and perfluorobutanesulfonyl fluoride were reacted, and the amino groups on the amino-functionalized graphene oxide reacted with the sulfonyl fluoride groups on perfluorobutanesulfonyl fluoride, thereby introducing a large number of fluorine atoms onto the surface of graphene oxide to obtain a polyfluorinated graphene modifier; Graphene has excellent mechanical strength. Adding it to the PU air pipe can significantly improve its mechanical properties. At the same time, the two-dimensional sheet structure of graphene can form an effective barrier in the PU matrix to prevent the diffusion of corrosive media and oily substances. At the same time, the fluorination treatment further enhances the corrosion resistance and hydrophobicity of graphene, enabling graphene to better play a protective role in the PU matrix. Detailed implementation mode

[0030] The following will combine the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0031] Example 1:

[0032] This example is a preparation method of a corrosion-resistant and oil-resistant PU air pipe, including the following steps:

[0033] Step S1: Add 10 mmol of cyanuric chloride, 22 mmol of hexafluoroisopropanol, and 50 mL of anhydrous acetonitrile into a three-necked flask equipped with a stirrer, a thermometer, and a gas pipe, and introduce nitrogen protection. Then, stir and react for 1 h under the conditions of a temperature of 0 °C and a stirring rate of 300 r / min. Then, continue to stir and react for 2 h under the condition of heating to 50 °C. After the reaction is completed, cool the reaction product to room temperature, and then rotate and evaporate to remove the solvent to obtain a disubstituted fluorinated intermediate.

[0034] Step S2: Add 33 mmol of the disubstituted fluorine-containing intermediate, 10 mmol of trimethylolpropane, 40 mmol of anhydrous potassium carbonate, and 80 mL of N,N-dimethylformamide into a three-necked flask equipped with a stirrer, a thermometer, and a gas pipe. Introduce nitrogen for protection. Then, stir and react at a temperature of 95 °C and a stirring rate of 300 r / min for 8 h. After the reaction ends, cool the reaction product to room temperature, then perform vacuum filtration. Rotate and evaporate the filtrate to remove the solvent. Then, wash it twice with anhydrous acetone, anhydrous ethanol, and distilled water in sequence. Then, place it in a vacuum drying oven and dry it at a temperature of 60 °C for 2 h to obtain the polyfluorotriazine ring modifier;

[0035] Step S3: Add 1 g of graphite powder, 35 mL of concentrated sulfuric acid with a mass fraction of 96%, and 11 mL of concentrated nitric acid with a mass fraction of 66% into a three-necked flask equipped with a stirrer, a thermometer, and a gas pipe. Introduce nitrogen for protection. Stir and react at a temperature of 25 °C and a stirring rate of 300 r / min for 5 min. Then, add 6 g of potassium permanganate and continue to stir and react at a temperature of 50 °C for 3 h. Then, continue to stir and react at a temperature of 90 °C for 3 h. After the reaction ends, cool the reaction product to room temperature, then pour it into 50 mL of hydrogen peroxide solution with a mass fraction of 1% at a temperature of 0 °C. Then, centrifuge it. Wash the precipitate three times with hydrochloric acid solution with a mass fraction of 3% and distilled water in sequence. Then, place it in a vacuum drying oven and dry it at a temperature of 50 °C for 4 h to obtain graphene oxide;

[0036] Step S4: Add 1 g of graphene oxide and 35 mL of ethanol solution with a volume fraction of 85% into a three-necked flask equipped with a stirrer, a thermometer, and a gas pipe. Introduce nitrogen for protection. Stir and react at a temperature of 25 °C and a stirring rate of 300 r / min for 5 min. Then, add 1 mL of 3-aminopropyltrimethoxysilane and continue to stir and react at a temperature of 60 °C for 15 h. After the reaction ends, cool the reaction product to room temperature, then centrifuge it. Wash the precipitate three times with anhydrous ethanol. Then, place it in a vacuum drying oven and dry it at a temperature of 50 °C for 4 h to obtain amino-functionalized graphene oxide;

[0037] Step S5: Add 1 g of amino-functionalized graphene oxide, 2 mL of triethylamine, and 40 mL of dichloromethane into a three-necked flask equipped with a stirrer, a thermometer, and a constant-pressure dropping funnel. Ultrasonically disperse for 20 min under the condition of an ultrasonic power of 250 W, then stir and react for 10 min at a temperature of 25 °C and a stirring rate of 300 r / min. Then, while stirring, gradually add dropwise 10 mL of a perfluorobutanesulfonyl fluoride-dichloromethane solution formed by dissolving 0.8 g of perfluorobutanesulfonyl fluoride in 10 mL of dichloromethane, control the dropping rate at 1 drop / s. After the dropping is completed, continue to stir and react at a temperature of 45 °C for 4 h. After the reaction is completed, cool the reaction product to room temperature, then centrifuge, wash the precipitate with anhydrous acetone three times, and then place it in a vacuum drying oven and dry at a temperature of 50 °C for 4 h to obtain a polyfluorinated graphene modifier;

[0038] Step S6: Weigh 70 parts by weight of polyurethane resin, 22 parts of ethylene propylene diene monomer rubber, 3 parts of polyfluorotriazine ring modifier, 0.3 parts of polyfluorinated graphene modifier, 8 parts of carbon black, 3 parts of talcum powder, 0.8 parts of zinc stearate, 0.2 parts of 2-mercaptobenzothiazole, 2 parts of dibutyl phthalate, 0.1 parts of 2,6-di-tert-butyl-p-cresol, and 0.1 parts of N-cyclohexyl-N'-phenyl-p-phenylenediamine, and set aside; the polyurethane resin is Wanhua TPU WHT-8185RV; the ethylene propylene diene monomer rubber is Dow IP4640L ethylene propylene diene monomer rubber from the United States;

[0039] Step S7: Mix the polyurethane resin, ethylene propylene diene monomer rubber, polyfluorotriazine ring modifier, polyfluorinated graphene modifier, carbon black, talcum powder, zinc stearate, 2-mercaptobenzothiazole, dibutyl phthalate, 2,6-di-tert-butyl-p-cresol, and N-cyclohexyl-N'-phenyl-p-phenylenediamine evenly, and then melt and extrude through an extruder, and cool and shape to obtain a corrosion-resistant and oil-resistant PU air tube.

[0040] Example 2:

[0041] The present embodiment is a preparation method of a corrosion-resistant and oil-resistant PU air tube, including the following steps:

[0042] Step S1: Add 10 mmol of cyanuric chloride, 24 mmol of hexafluoroisopropanol, and 55 mL of anhydrous acetonitrile into a three-necked flask equipped with a stirrer, a thermometer, and a gas guide tube, introduce nitrogen protection, then stir and react for 1.5 h at a temperature of 3 °C and a stirring rate of 350 r / min, then continue to stir and react at a temperature of 52 °C for 2.5 h. After the reaction is completed, cool the reaction product to room temperature, and then rotate and evaporate to remove the solvent to obtain a disubstituted fluorinated intermediate;

[0043] Step S2: Add 35 mmol of a disubstituted fluorine-containing intermediate, 10 mmol of trimethylolpropane, 42 mmol of anhydrous potassium carbonate, and 90 mL of N,N-dimethylformamide into a three-necked flask equipped with a stirrer, a thermometer, and a gas pipe. Protect with nitrogen. Then, stir and react at a temperature of 100 °C and a stirring rate of 350 r / min for 9 h. After the reaction ends, cool the reaction product to room temperature, then perform vacuum filtration. Rotate and evaporate the filtrate to remove the solvent. Then, wash it twice with anhydrous acetone, anhydrous ethanol, and distilled water in sequence. Then, place it in a vacuum drying oven and dry it at a temperature of 62 °C for 2.5 h to obtain a polyfluorotriazine ring modifier;

[0044] Step S3: Add 1 g of graphite powder, 38 mL of concentrated sulfuric acid with a mass fraction of 97%, and 12 mL of concentrated nitric acid with a mass fraction of 67% into a three-necked flask equipped with a stirrer, a thermometer, and a gas pipe. Protect with nitrogen. Stir and react at a temperature of 28 °C and a stirring rate of 350 r / min for 7 min. Then, add 7 g of potassium permanganate and continue to stir and react at a temperature of 52 °C for 4 h. Then, continue to stir and react at a temperature of 95 °C for 4 h. After the reaction ends, cool the reaction product to room temperature, then pour it into 55 mL of hydrogen peroxide solution with a mass fraction of 1.5% at a temperature of 3 °C. Then, centrifuge. Wash the precipitate four times with a hydrochloric acid solution with a mass fraction of 4% and distilled water in sequence. Then, place it in a vacuum drying oven and dry it at a temperature of 52 °C for 4.5 h to obtain graphene oxide;

[0045] Step S4: Add 1 g of graphene oxide and 38 mL of ethanol solution with a volume fraction of 88% into a three-necked flask equipped with a stirrer, a thermometer, and a gas pipe. Protect with nitrogen. Stir and react at a temperature of 28 °C and a stirring rate of 350 r / min for 8 min. Then, add 3 mL of 3-aminopropyltrimethoxysilane and continue to stir and react at a temperature of 62 °C for 18 h. After the reaction ends, cool the reaction product to room temperature, then centrifuge. Wash the precipitate four times with anhydrous ethanol. Then, place it in a vacuum drying oven and dry it at a temperature of 52 °C for 4.5 h to obtain amino-functionalized graphene oxide;

[0046] Step S5: Add 1 g of amino-functionalized graphene oxide, 2.5 mL of triethylamine, and 45 mL of dichloromethane into a three-necked flask equipped with a stirrer, a thermometer, and a constant-pressure dropping funnel. Ultrasonically disperse for 25 min under the condition of an ultrasonic power of 300 W. Then, carry out a stirring reaction for 15 min at a temperature of 28 °C and a stirring rate of 350 r / min. After that, while stirring, gradually add dropwise 12 mL of a perfluorobutanesulfonyl fluoride-dichloromethane solution formed by dissolving 1.2 g of perfluorobutanesulfonyl fluoride in 10 mL of dichloromethane, control the dropping rate at 1 drop / s. After the dropping is completed, continue the stirring reaction for 5 h under the condition of heating to 48 °C. After the reaction is completed, cool the reaction product to room temperature, then centrifuge, wash the precipitate 4 times with anhydrous acetone, and then place it in a vacuum drying oven and dry for 4.5 h at a temperature of 52 °C to obtain a polyfluorinated graphene modifier;

[0047] Step S6: Weigh 75 parts by weight of polyurethane resin, 27 parts of ethylene propylene diene monomer rubber, 7 parts of polyfluorotriazine ring modifier, 1.0 part of polyfluorinated graphene modifier, 12 parts of carbon black, 5 parts of talcum powder, 1.5 parts of zinc stearate, 0.3 part of 2-mercaptobenzothiazole, 4 parts of dibutyl phthalate, 0.2 part of 2,6-di-tert-butyl-p-cresol, and 0.2 part of N-cyclohexyl-N'-phenyl-p-phenylenediamine, and set aside; the polyurethane resin is Wanhua TPU WHT-8185RV; the ethylene propylene diene monomer rubber is Dow IP4640L ethylene propylene diene monomer rubber from the United States;

[0048] Step S7: Mix the polyurethane resin, ethylene propylene diene monomer rubber, polyfluorotriazine ring modifier, polyfluorinated graphene modifier, carbon black, talcum powder, zinc stearate, 2-mercaptobenzothiazole, dibutyl phthalate, 2,6-di-tert-butyl-p-cresol, and N-cyclohexyl-N'-phenyl-p-phenylenediamine evenly, and then melt-extrude through an extruder and cool and shape to obtain a corrosion-resistant and oil-resistant PU air tube.

[0049] Example 3:

[0050] This example is a preparation method of a corrosion-resistant and oil-resistant PU air tube, including the following steps:

[0051] Step S1: Add 10 mmol of cyanuric chloride, 26 mmol of hexafluoroisopropanol, and 60 mL of anhydrous acetonitrile into a three-necked flask equipped with a stirrer, a thermometer, and a gas guide tube, introduce nitrogen for protection, then carry out a stirring reaction for 2 h at a temperature of 5 °C and a stirring rate of 400 r / min, and then continue the stirring reaction for 3 h at a temperature of 55 °C. After the reaction is completed, cool the reaction product to room temperature, and then remove the solvent by rotary evaporation to obtain a disubstituted fluorinated intermediate;

[0052] Step S2: Add 36 mmol of a disubstituted fluorine-containing intermediate, 10 mmol of trimethylolpropane, 45 mmol of anhydrous potassium carbonate, and 100 mL of N,N-dimethylformamide into a three-necked flask equipped with a stirrer, a thermometer, and a gas pipe. Protect it by introducing nitrogen. Then, stir and react for 10 h under the conditions of a temperature of 100 °C and a stirring rate of 400 r / min. After the reaction is completed, cool the reaction product to room temperature, then perform vacuum filtration. Rotate and evaporate the filtrate to remove the solvent. Then, wash it three times with anhydrous acetone, anhydrous ethanol, and distilled water in sequence. Then, place it in a vacuum drying oven and dry it for 3 h under the condition of a temperature of 65 °C to obtain a polyfluorotriazine ring modifier;

[0053] Step S3: Add 1 g of graphite powder, 40 mL of concentrated sulfuric acid with a mass fraction of 98%, and 13 mL of concentrated nitric acid with a mass fraction of 68% into a three-necked flask equipped with a stirrer, a thermometer, and a gas pipe. Protect it by introducing nitrogen. Stir and react for 10 min under the conditions of a temperature of 30 °C and a stirring rate of 400 r / min. Then, add 8 g of potassium permanganate and continue to stir and react for 5 h under the condition of heating to 55 °C. Then, continue to stir and react for 5 h under the condition of heating to 100 °C. After the reaction is completed, cool the reaction product to room temperature, then pour it into 60 mL of hydrogen peroxide solution with a mass fraction of 2% at a temperature of 5 °C. Then, centrifuge it. Wash the precipitate five times with a hydrochloric acid solution with a mass fraction of 5% and distilled water in sequence. Then, place it in a vacuum drying oven and dry it for 5 h under the condition of a temperature of 55 °C to obtain graphene oxide;

[0054] Step S4: Add 1 g of graphene oxide and 40 mL of ethanol solution with a volume fraction of 90% into a three-necked flask equipped with a stirrer, a thermometer, and a gas pipe. Protect it by introducing nitrogen. Stir and react for 10 min under the conditions of a temperature of 30 °C and a stirring rate of 400 r / min. Then, add 5 mL of 3-aminopropyltrimethoxysilane and continue to stir and react for 20 h under the condition of heating to 65 °C. After the reaction is completed, cool the reaction product to room temperature, then centrifuge it. Wash the precipitate five times with anhydrous ethanol. Then, place it in a vacuum drying oven and dry it for 5 h under the condition of a temperature of 55 °C to obtain amino-functionalized graphene oxide;

[0055] Step S5: Add 1 g of amino-functionalized graphene oxide, 3 mL of triethylamine, and 50 mL of dichloromethane into a three-necked flask equipped with a stirrer, a thermometer, and a constant-pressure dropping funnel. Ultrasonically disperse for 30 min under the condition of an ultrasonic power of 350 W. Then, stir and react for 20 min at a temperature of 30 °C and a stirring rate of 400 r / min. After that, while stirring, gradually add dropwise 15 mL of a perfluorobutanesulfonyl fluoride-dichloromethane solution formed by dissolving 1.6 g of perfluorobutanesulfonyl fluoride in 10 mL of dichloromethane, control the dropping rate at 2 drops / s. After the dropping is completed, continue to stir and react at 50 °C for 6 h. After the reaction ends, cool the reaction product to room temperature, then centrifuge, wash the precipitate with anhydrous acetone 5 times, and then place it in a vacuum drying oven and dry at 55 °C for 5 h to obtain a polyfluorinated graphene modifier;

[0056] Step S6: Weigh 80 parts of polyurethane resin, 34 parts of ethylene propylene diene monomer rubber, 11 parts of polyfluorotriazine ring modifier, 1.7 parts of polyfluorinated graphene modifier, 14 parts of carbon black, 7 parts of talcum powder, 2.2 parts of zinc stearate, 0.4 part of 2-mercaptobenzothiazole, 6 parts of dibutyl phthalate, 0.3 part of 2,6-di-tert-butyl-p-cresol, and 0.3 part of N-cyclohexyl-N'-phenyl-p-phenylenediamine by weight, and set aside; the polyurethane resin is Wanhua TPU WHT-8185RV; the ethylene propylene diene monomer rubber is Dow IP4640L ethylene propylene diene monomer rubber from the United States;

[0057] Step S7: Mix the polyurethane resin, ethylene propylene diene monomer rubber, polyfluorotriazine ring modifier, polyfluorinated graphene modifier, carbon black, talcum powder, zinc stearate, 2-mercaptobenzothiazole, dibutyl phthalate, 2,6-di-tert-butyl-p-cresol, and N-cyclohexyl-N'-phenyl-p-phenylenediamine evenly, and then melt and extrude through an extruder, and cool and shape to obtain a corrosion-resistant and oil-resistant PU air tube.

[0058] Comparative Example 1:

[0059] This comparative example is a preparation method of a corrosion-resistant and oil-resistant PU air tube, including the following steps:

[0060] Step S1: Weigh 80 parts of polyurethane resin, 34 parts of ethylene propylene diene monomer rubber, 14 parts of carbon black, 7 parts of talcum powder, 2.2 parts of zinc stearate, 0.4 part of 2-mercaptobenzothiazole, 6 parts of dibutyl phthalate, 0.3 part of 2,6-di-tert-butyl-p-cresol, and 0.3 part of N-cyclohexyl-N'-phenyl-p-phenylenediamine by weight, and set aside; the polyurethane resin is Wanhua TPU WHT-8185RV; the ethylene propylene diene monomer rubber is Dow IP4640L ethylene propylene diene monomer rubber from the United States;

[0061] Step S2: Mix polyurethane resin, ethylene propylene diene monomer (EPDM), carbon black, talcum powder, zinc stearate, 2-mercaptobenzothiazole, dibutyl phthalate, 2,6-di-tert-butyl-p-cresol, and N-cyclohexyl-N'-phenyl-p-phenylenediamine evenly, then melt and extrude through an extruder, and cool and shape to obtain a corrosion-resistant and oil-resistant PU air tube.

[0062] Comparative Example 2:

[0063] This comparative example is a preparation method of a corrosion-resistant and oil-resistant PU air tube, including the following steps:

[0064] Step S1: Add 10 mmol of cyanuric chloride, 26 mmol of hexafluoroisopropanol, and 60 mL of anhydrous acetonitrile into a three-necked flask equipped with a stirrer, a thermometer, and a gas guide tube, introduce nitrogen for protection, then stir and react for 2 h under the conditions of a temperature of 5°C and a stirring rate of 400 r / min, then continue to stir and react for 3 h under the condition of heating to 55°C. After the reaction is completed, cool the reaction product to room temperature, then rotate and evaporate to remove the solvent to obtain a disubstituted fluorinated intermediate;

[0065] Step S2: Add 36 mmol of disubstituted fluorinated intermediate, 10 mmol of trimethylolpropane, 45 mmol of anhydrous potassium carbonate, and 100 mL of N,N-dimethylformamide into a three-necked flask equipped with a stirrer, a thermometer, and a gas guide tube, introduce nitrogen for protection, then stir and react for 10 h under the conditions of a temperature of 100°C and a stirring rate of 400 r / min. After the reaction is completed, cool the reaction product to room temperature, then vacuum filter, rotate and evaporate the filtrate to remove the solvent, then wash 3 times with anhydrous acetone, anhydrous ethanol, and distilled water in sequence, and then place it in a vacuum drying oven and dry for 3 h under the condition of a temperature of 65°C to obtain a polyfluorotriazine ring modifier;

[0066] Step S3: Weigh 80 parts of polyurethane resin, 34 parts of ethylene propylene diene monomer (EPDM), 11 parts of polyfluorotriazine ring modifier, 14 parts of carbon black, 7 parts of talcum powder, 2.2 parts of zinc stearate, 0.4 part of 2-mercaptobenzothiazole, 6 parts of dibutyl phthalate, 0.3 part of 2,6-di-tert-butyl-p-cresol, and 0.3 part of N-cyclohexyl-N'-phenyl-p-phenylenediamine by weight for standby; the polyurethane resin is Wanhua TPU WHT-8185RV; the ethylene propylene diene monomer (EPDM) is Dow IP4640L ethylene propylene diene monomer (EPDM) from the United States;

[0067] Step S4: Mix polyurethane resin, ethylene propylene diene monomer (EPDM), polyfluoro triazine ring modifier, carbon black, talcum powder, zinc stearate, 2-mercaptobenzothiazole, dibutyl phthalate, 2,6-di-tert-butyl-p-cresol, and N-cyclohexyl-N'-phenyl-p-phenylenediamine evenly, then melt and extrude through an extruder, and obtain a corrosion-resistant and oil-resistant PU air tube after cooling and shaping.

[0068] Comparative Example 3:

[0069] This comparative example is a preparation method of a corrosion-resistant and oil-resistant PU air tube, including the following steps:

[0070] Step S1: Add 1 g of graphite powder, 40 mL of concentrated sulfuric acid with a mass fraction of 98%, and 13 mL of concentrated nitric acid with a mass fraction of 68% into a three-necked flask equipped with a stirrer, a thermometer, and a gas pipe, introduce nitrogen protection, stir and react for 10 min at a temperature of 30 °C and a stirring rate of 400 r / min, then add 8 g of potassium permanganate and continue to stir and react for 5 h at a temperature of 55 °C, then continue to stir and react for 5 h at a temperature of 100 °C. After the reaction is completed, cool the reaction product to room temperature, then pour it into 60 mL of hydrogen peroxide solution with a mass fraction of 2% at a temperature of 5 °C, then centrifuge, wash the precipitate with a hydrochloric acid solution with a mass fraction of 5% and distilled water 5 times successively, and then place it in a vacuum drying oven and dry for 5 h at a temperature of 55 °C to obtain graphene oxide;

[0071] Step S2: Add 1 g of graphene oxide and 40 mL of ethanol solution with a volume fraction of 90% into a three-necked flask equipped with a stirrer, a thermometer, and a gas pipe, introduce nitrogen protection, stir and react for 10 min at a temperature of 30 °C and a stirring rate of 400 r / min, then add 5 mL of 3-aminopropyltrimethoxysilane and continue to stir and react for 20 h at a temperature of 65 °C. After the reaction is completed, cool the reaction product to room temperature, then centrifuge, wash the precipitate with anhydrous ethanol 5 times, and then place it in a vacuum drying oven and dry for 5 h at a temperature of 55 °C to obtain amino-functionalized graphene oxide;

[0072] Step S3: Add 1 g of amino-functionalized graphene oxide, 3 mL of triethylamine, and 50 mL of dichloromethane into a three-necked flask equipped with a stirrer, a thermometer, and a constant-pressure dropping funnel. Ultrasonically disperse for 30 min under the condition of an ultrasonic power of 350 W. Then, stir and react for 20 min under the conditions of a temperature of 30 °C and a stirring rate of 400 r / min. After that, while stirring, gradually add dropwise 15 mL of a perfluorobutanesulfonyl fluoride-dichloromethane solution formed by dissolving 1.6 g of perfluorobutanesulfonyl fluoride in 10 mL of dichloromethane, control the dropping rate at 2 drops / s. After the dropping is completed, continue to stir and react at 50 °C for 6 h. After the reaction is completed, cool the reaction product to room temperature, then centrifuge, wash the precipitate 5 times with anhydrous acetone, and then place it in a vacuum drying oven and dry at 55 °C for 5 h to obtain a polyfluorinated graphene modifier;

[0073] Step S4: Weigh 80 parts of polyurethane resin, 34 parts of ethylene propylene diene monomer rubber, 1.7 parts of polyfluorinated graphene modifier, 14 parts of carbon black, 7 parts of talcum powder, 2.2 parts of zinc stearate, 0.4 part of 2-mercaptobenzothiazole, 6 parts of dibutyl phthalate, 0.3 part of 2,6-di-tert-butyl-p-cresol, and 0.3 part of N-cyclohexyl-N'-phenyl-p-phenylenediamine according to weight parts for standby; the polyurethane resin is Wanhua TPU WHT-8185RV; the ethylene propylene diene monomer rubber is Dow IP4640L ethylene propylene diene monomer rubber from the United States;

[0074] Step S5: Mix the polyurethane resin, ethylene propylene diene monomer rubber, polyfluorinated graphene modifier, carbon black, talcum powder, zinc stearate, 2-mercaptobenzothiazole, dibutyl phthalate, 2,6-di-tert-butyl-p-cresol, and N-cyclohexyl-N'-phenyl-p-phenylenediamine evenly, and then melt and extrude through an extruder, and cool and shape to obtain a corrosion-resistant and oil-resistant PU air tube.

[0075] Measure the tensile strength of the corrosion-resistant and oil-resistant PU air tubes of Examples 1-3 and Comparative Examples 1-3 according to the GB / T528-2009 standard, and the measurement results are shown in the following table;

[0076]

[0077] Referring to the data in the above table, according to the comparison between Examples 1-3 and Comparative Examples 1-3, it can be known that the corrosion-resistant and oil-resistant PU air tubes of the present application have excellent corrosion resistance and oil resistance.

[0078] Among them, the acid corrosion retention rate = tensile property after acid treatment / tensile property before acid treatment × 100%; among them, the acid treatment method is: immerse the sample in a sulfuric acid solution with a mass fraction of 5% for 30 d, then take it out, wash it with distilled water until neutral, and test it after drying.

[0079] Among them, the alkali corrosion retention rate = tensile property after alkali treatment / tensile property before alkali treatment × 100%; among them, the alkali treatment method is: immerse the sample in a sodium hydroxide solution with a mass fraction of 5% for 30 days, then take it out, wash it with distilled water until neutral, dry it, and then test it.

[0080] Among them, the oil corrosion retention rate = tensile property after oil treatment / tensile property before oil treatment × 100%; among them, the oil treatment method is: immerse the sample in IRM902 rubber test oil for 30 days, then take it out, wash it with distilled water until neutral, dry it, and then test it.

[0081] In the description of this specification, the description referring to terms such as "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0082] The above content is only an example and illustration of the present invention. Those skilled in the art of this technology can make various modifications or supplements to the described specific embodiments or use similar methods for substitution. As long as they do not deviate from the invention or exceed the scope defined by this application, they shall fall within the protection scope of the present invention.

Claims

1. A corrosion-resistant and oil-resistant PU air pipe, characterized in that: It comprises the following components in parts by weight: 70-80 parts of polyurethane resin, 22-34 parts of EPDM rubber, 3-11 parts of polyfluorotriazine ring modifier, 0.3-1.7 parts of polyfluoro graphene modifier, 8-14 parts of carbon black, 3-7 parts of talc, 0.8-2.2 parts of zinc stearate, 0.2-0.4 parts of 2-mercaptobenzothiazole, 2-6 parts of dibutyl phthalate, 0.1-0.3 parts of 2,6-di-tert-butyl-p-cresol and 0.1-0.3 parts of N-cyclohexyl-N'-phenyl-p-phenylenediamine; Wherein, the polyfluorotriazine ring modifier is prepared by the following steps: Step a1: Add cyanuric chloride, hexafluoroisopropanol and anhydrous acetonitrile into a three-necked flask equipped with a stirrer, a thermometer and a gas guide tube, introduce nitrogen protection, and then stir the reaction at a temperature of 0-5°C and a stirring rate of 300-400r / min for 1-2h, then heat the temperature to 50-55°C and continue stirring the reaction for 2-3h. After the reaction is completed, the reaction product is cooled to room temperature, and then the solvent is removed by rotary evaporation to obtain a disubstituted fluorine-containing intermediate; Step a2: Add the disubstituted fluorine-containing intermediate, trimethylolpropane, anhydrous potassium carbonate and N,N-dimethylformamide into a three-necked flask equipped with a stirrer, a thermometer and an air duct, introduce nitrogen protection, and then stir the reaction at a temperature of 95-100°C and a stirring rate of 300-400r / min for 8-10h. After the reaction, cool the reaction product to room temperature, vacuum filter, and rotary evaporate the filtrate to remove the solvent. Then wash it with anhydrous acetone, anhydrous ethanol and distilled water for 2-3 times in sequence, and then place it in a vacuum drying oven and dry it at a temperature of 60-65°C for 2-3h to obtain a polyfluorotriazine ring modifier.

2. The corrosion-resistant and oil-resistant PU air pipe according to claim 1, characterized in that: The usage ratio of cyanuric chloride, hexafluoroisopropanol and anhydrous acetonitrile in step a1 is 10mmol:22-26mmol:50-60mL.

3. The corrosion-resistant and oil-resistant PU air pipe according to claim 1, characterized in that: The usage ratio of the disubstituted fluorinated intermediate, trimethylolpropane, anhydrous potassium carbonate and N,N-dimethylformamide in step a2 is 33-36 mmol: 10 mmol: 40-45 mmol: 80-100 mL.

4. The corrosion-resistant and oil-resistant PU air pipe according to claim 1, characterized in that: The polyfluorinated graphene modifier is prepared by the following steps: Step b1: adding graphite powder, concentrated sulfuric acid and concentrated nitric acid to a three-necked flask equipped with an agitator, a thermometer and an air duct, introducing nitrogen protection, stirring and reacting for 5-10 minutes at a temperature of 25-30°C and a stirring rate of 300-400r / min, then adding potassium permanganate and heating to 50-55°C and continuing to stir and react for 3-5 hours, then heating to 90-100°C and continuing to stir and react for 3-5 hours, after the reaction is completed, the reaction product is cooled to room temperature, then poured into a hydrogen peroxide solution at a temperature of 0-5°C, then centrifuged, and the precipitate is washed with hydrochloric acid solution and distilled water for 3-5 times in sequence, then placed in a vacuum drying oven, and dried at a temperature of 50-55°C for 4-5 hours to obtain graphene oxide; Step b2: adding graphene oxide and ethanol solution to a three-necked flask equipped with a stirrer, a thermometer and an air duct, introducing nitrogen protection, stirring the reaction for 5-10 minutes at a temperature of 25-30°C and a stirring rate of 300-400r / min, then adding 3-aminopropyltrimethoxysilane and heating to 60-65°C and continuing to stir the reaction for 15-20 hours, cooling the reaction product to room temperature after the reaction is completed, and then centrifuging it, washing the precipitate with anhydrous ethanol for 3-5 times, and then placing it in a vacuum drying oven, and drying it at a temperature of 50-55°C for 4-5 hours to obtain amino-modified graphene oxide; Step b3: Add the aminated graphene oxide, triethylamine and dichloromethane to a three-necked flask equipped with a stirrer, a thermometer and a constant pressure dropping funnel, and ultrasonically disperse for 20-30 minutes at an ultrasonic power of 250-350W, then stir and react for 10-20 minutes at a temperature of 25-30°C and a stirring rate of 300-400r / min, then add perfluorobutylsulfonyl fluoride-dichloromethane solution dropwise while stirring, and control the dropping rate to 1-2 drops / s. After the addition is completed, the temperature is raised to 45-50°C and the stirring reaction is continued for 4-6 hours. After the reaction is completed, the reaction product is cooled to room temperature and then centrifuged. The precipitate is washed with anhydrous acetone for 3-5 times, and then placed in a vacuum drying oven and dried at a temperature of 50-55°C for 4-5 hours to obtain a polyfluoro graphene modifier.

5. The corrosion-resistant and oil-resistant PU air pipe according to claim 4, characterized in that: The usage ratio of the graphite powder, concentrated sulfuric acid, concentrated nitric acid, potassium permanganate and hydrogen peroxide solution in step b1 is 1g:35-40mL:11-13mL:6-8g:50-60mL.

6. The corrosion-resistant and oil-resistant PU air pipe according to claim 4, characterized in that: The mass fraction of the concentrated sulfuric acid in step b1 is 96-98%, the mass fraction of the concentrated nitric acid is 66-68%, the mass fraction of the hydrogen peroxide solution is 1-2%, and the mass fraction of the hydrochloric acid solution is 3-5%.

7. The corrosion-resistant and oil-resistant PU air pipe according to claim 4, characterized in that: The usage ratio of the graphene oxide, the ethanol solution and the 3-aminopropyltrimethoxysilane in step b2 is 1 g: 35-40 mL: 1-5 mL; the volume fraction of the ethanol solution is 85-90%.

8. The corrosion-resistant and oil-resistant PU air pipe according to claim 4, characterized in that: The usage ratio of the amino-modified graphene oxide, triethylamine, dichloromethane and perfluorobutylsulfonyl fluoride-dichloromethane solution in step b3 is 1 g: 2-3 mL: 40-50 mL: 10-15 mL.

9. The corrosion-resistant and oil-resistant PU air pipe according to claim 4, characterized in that: The perfluorobutylsulfonyl fluoride-dichloromethane solution in step b3 is a solution formed by dissolving perfluorobutylsulfonyl fluoride in dichloromethane at a ratio of 0.8-1.6 g:10 mL.

10. A method for preparing a corrosion-resistant and oil-resistant PU air pipe, characterized in that: The following steps are involved: Step 1: Weigh 70-80 parts of polyurethane resin, 22-34 parts of EPDM rubber, 3-11 parts of polyfluorotriazine ring modifier, 0.3-1.7 parts of polyfluoro graphene modifier, 8-14 parts of carbon black, 3-7 parts of talc, 0.8-2.2 parts of zinc stearate, 0.2-0.4 parts of 2-mercaptobenzothiazole, 2-6 parts of dibutyl phthalate, 0.1-0.3 parts of 2,6-di-tert-butyl-p-cresol and 0.1-0.3 parts of N-cyclohexyl-N'-phenyl-p-phenylenediamine according to weight parts, and set aside; the polyurethane resin is Wanhua TPU WHT-8185RV; the EPDM rubber is Dow IP4640L EPDM rubber; Step 2: Evenly mix the polyurethane resin, EPDM rubber, polyfluorotriazine ring modifier, polyfluorographene modifier, carbon black, talc, zinc stearate, 2-mercaptobenzothiazole, dibutyl phthalate, 2,6-di-tert-butyl-p-cresol and N-cyclohexyl-N'-phenyl-p-phenylenediamine, and then melt-extrude through an extruder, cool and shape, and obtain a corrosion-resistant and oil-resistant PU air pipe.

Images