Preparation method of wear-resistant organic composite material

Abstract

The invention belongs to the technical field of organic composite materials, and discloses a preparation method of a wear-resistant organic composite material. The preparation method comprises the following steps: mixing polytetrafluoroethylene, nylon, a modified filler and a metal-organic framework material with a three-dimensional network structure, drying, carrying out extrusion molding, and calcining to obtain the organic composite material, a preparation process of the modified filler comprises the following steps: stirring and mixing water and hexafluoroisopropanol, then adding a silane coupling agent, polyimide, polyethylene glycol, nano molybdenum disulfide, nano hexagonal boron nitride and carbon nanotubes, and stirring and mixing to obtain the modified filler. The modified filler prepared by a specific method and the metal-organic framework material with a three-dimensional network structure are matched with polytetrafluoroethylene and nylon, so that the wear resistance and the tensile strength of the organic composite material are remarkably improved. The application of the organic composite material in mechanical equipment is facilitated.

Description

Technical Field

[0001] The invention belongs to the technical field of organic composite materials, and particularly relates to a method for preparing a wear-resistant organic composite material. Background Art

[0002] Organic composite materials are widely used in sealing parts of mechanical equipment. For example, in some equipment with high sealing requirements, organic composite materials are often used for sealing connections. However, the sealing of existing organic composite materials is relatively easy to achieve, but the wear resistance is often insufficient. Due to the lack of wear resistance, the sealing of the material is further likely to decrease.

[0003] Some organic composite materials in the prior art have relatively low mechanical properties, such as tensile strength, which is also not conducive to the application of organic composite materials.

[0004] Therefore, there is an urgent need to provide an organic composite material with good wear resistance, which is conducive to the application of organic composite materials in mechanical equipment. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems existing in the above-mentioned prior art. The present invention provides a method for preparing a wear-resistant organic composite material. The organic composite material prepared by the preparation method of the present invention has good wear resistance and further has good tensile strength. The modified filler (the modified filler contains specific two-dimensional materials and one-dimensional materials) prepared by a specific method of the present invention, and the metal-organic framework material with a three-dimensional network structure are combined with polytetrafluoroethylene and nylon to significantly improve the wear resistance and tensile strength of the organic composite material. This is conducive to the application of the organic composite material of the present invention in mechanical equipment.

[0006] In order to solve the above problems, the present invention provides the following technical solutions:

[0007] A method for preparing a wear-resistant organic composite material comprises the following steps:

[0008] The organic composite material is obtained by mixing polytetrafluoroethylene, nylon, modified filler, and a metal-organic framework material having a three-dimensional network structure, drying, extruding, and calcining.

[0009] The preparation process of the modified filler comprises: stirring and mixing water and hexafluoroisopropanol, and then adding silane coupling agent, polyimide, polyethylene glycol, nano molybdenum disulfide, nano hexagonal boron nitride and carbon nanotubes and stirring and mixing to obtain the modified filler.

[0010] Preferably, the weight ratio of water to hexafluoroisopropanol is 10:(1-8), more preferably 10:(2-6).

[0011] Preferably, the weight ratio of water to silane coupling agent, polyimide, polyethylene glycol, nano-molybdenum disulfide, nano-hexagonal boron nitride, and carbon nanotubes is 10: (0.5-3): (3-8): (0.5-3): (0.5-1.5): (0.1-1): (0.1-0.5), and further preferably is 10: (1-2): (4-7): (1-2): (0.8-1.2): (0.2-0.9): (0.1-0.5).

[0012] Preferably, the nylon is selected from at least one of PA46 and PA9T.

[0013] Preferably, the silane coupling agent is selected from at least one of KH550 and KH560.

[0014] Preferably, the metal-organic framework material having a three-dimensional network structure is a three-dimensional network structure comprising a combination of cobalt ions, 4,4'-di(4-pyridyl)biphenyl ligands, oxalic acid ligands and phosphotungstate anions. The molecular formula of the metal-organic framework material having a three-dimensional network structure is C 210 H 156 N 18 O 92 P2W 18 Co9.

[0015] Preferably, the weight ratio of the polytetrafluoroethylene, nylon, modified filler and metal-organic framework material with a three-dimensional network structure is 65-85: (5-10): (5-20): (1.5-4.5); further preferably, the weight ratio of the polytetrafluoroethylene, nylon, modified filler and metal-organic framework material with a three-dimensional network structure is 80-85: (5-8): (8-15): (2-4.5).

[0016] Preferably, the drying temperature is 60-80° C., and the drying time is 6-20 hours.

[0017] Preferably, the extrusion molding pressure is 30-50 MPa, and the extrusion molding time is 10-25 minutes.

[0018] Preferably, the calcination holding temperature is 220-350°C, more preferably 260-300°C.

[0019] Preferably, the calcination holding time is 60-80 minutes, more preferably 70-80 minutes.

[0020] Preferably, the heating temperature during calcination starts from room temperature and is increased at a rate of 3-8°C / min.

[0021] Preferably, the calcination can be performed in an air environment.

[0022] Preferably, during the preparation of the modified filler, nano tungsten disulfide is also added when nano molybdenum disulfide is added. The further addition of nano tungsten disulfide makes the prepared modified filler have better compatibility with the metal-organic framework material with a three-dimensional network structure (both nano tungsten disulfide and the metal-organic framework material with a three-dimensional network structure contain tungsten, which is conducive to improving the dispersion uniformity of the two-dimensional nano tungsten disulfide), thereby further improving the wear resistance of the organic composite material.

[0023] Preferably, the weight ratio of the nano tungsten disulfide to the nano molybdenum disulfide is 1:(0.2-1).

[0024] A wear-resistant organic composite material is prepared by the above preparation method.

[0025] A device comprises the above organic composite material.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] (1) The modified filler prepared by the specific method of the present invention and the metal-organic framework material with a three-dimensional network structure combined with polytetrafluoroethylene and nylon significantly improve the wear resistance and tensile strength of the organic composite material. This is conducive to the application of the organic composite material of the present invention in mechanical equipment.

[0028] (2) In the process of preparing the modified filler, the present invention adds polyimide, nano molybdenum disulfide, nano hexagonal boron nitride, and carbon nanotubes to the mixed solvent of water and hexafluoroisopropanol. With the auxiliary effect of silane coupling agent and polyethylene glycol, the compatibility of each component is improved, so that polyimide, nano molybdenum disulfide, nano hexagonal boron nitride, and carbon nanotubes can be evenly dispersed. When the formed modified filler is further mixed with polytetrafluoroethylene, nylon, and metal-organic framework material with a three-dimensional network structure, due to the polyfluoride characteristics of hexafluoroisopropanol, the dispersion uniformity of each component (polytetrafluoroethylene, nylon, metal-organic framework material with a three-dimensional network structure, and modified filler) is further improved, and the modified filler can also be evenly dispersed in the metal-organic framework material with a three-dimensional network structure, and further evenly dispersed in polytetrafluoroethylene. Since nylon, modified filler, and metal-organic framework material with a three-dimensional network structure have good dispersibility in polytetrafluoroethylene, the organic composite material finally obtained has good wear resistance and tensile strength. DETAILED DESCRIPTION

[0029] In order to make the technical scheme of the present invention more clearly understood by those skilled in the art, the following embodiments are listed for illustration. It should be pointed out that the following embodiments do not limit the protection scope of the present invention.

[0030] Unless otherwise specified, the raw materials, reagents or devices used in the following examples can be obtained from conventional commercial sources or by existing known methods.

[0031] The metal-organic framework material with a three-dimensional network structure used in the following examples is prepared from Example 1 of CN117964909A. Nylon is a powdered nylon with a mesh size of 200 meshes.

[0032] Example 1

[0033] A method for preparing a wear-resistant organic composite material comprises the following steps:

[0034] Polytetrafluoroethylene, nylon (PA46), modified filler, and metal-organic framework material with a three-dimensional network structure are stirred and mixed at a stirring rate of 500 rpm for 20 minutes, dried at 70°C for 14 hours, and then extruded at a pressure of 48 MPa for 20 minutes, and then calcined. The calcination process is in an air atmosphere, starting from room temperature, and heating to 330°C at a rate of 4°C / min for 70 minutes to obtain an organic composite material;

[0035] The preparation process of the modified filler includes: stirring and mixing water and hexafluoroisopropanol, and then adding silane coupling agent (KH550), polyimide, polyethylene glycol 400, nano molybdenum disulfide, nano hexagonal boron nitride, and carbon nanotubes, stirring and mixing, stirring at a rate of 600 revolutions per minute, stirring for 60 minutes, and obtaining the modified filler; the weight ratio of water to hexafluoroisopropanol is 10:3;

[0036] The weight ratio of water to silane coupling agent, polyimide, polyethylene glycol 400, nano molybdenum disulfide, nano hexagonal boron nitride, and carbon nanotube is 10:1:7:2:1:0.2:0.3;

[0037] The weight ratio of polytetrafluoroethylene, nylon, modified filler, and metal-organic framework material with a three-dimensional network structure is 80:5:12:3.

[0038] Example 2

[0039] A method for preparing a wear-resistant organic composite material comprises the following steps:

[0040] Polytetrafluoroethylene, nylon (PA9T), modified filler, and metal-organic framework material with a three-dimensional network structure are stirred and mixed at a rate of 500 rpm for 20 minutes, dried at 75°C for 12 hours, and then extruded at a pressure of 45MPa for 20 minutes, and then calcined. The calcination process is in an air atmosphere, starting from room temperature, and heating to 340°C at a rate of 5°C / min for 70 minutes to obtain an organic composite material;

[0041] The preparation process of the modified filler includes: stirring and mixing water and hexafluoroisopropanol, and then adding silane coupling agent (KH560), polyimide, polyethylene glycol 400, nano molybdenum disulfide, nano hexagonal boron nitride, and carbon nanotubes, stirring and mixing, the stirring rate is 600 revolutions per minute, stirring for 70 minutes, and obtaining the modified filler; the weight ratio of water to hexafluoroisopropanol is 10:4;

[0042] The weight ratio of water to silane coupling agent, polyimide, polyethylene glycol 400, nano molybdenum disulfide, nano hexagonal boron nitride, and carbon nanotube is 10:1.5:8:1.5:0.8:0.4:0.2;

[0043] The weight ratio of polytetrafluoroethylene, nylon, modified filler, and metal-organic framework material with a three-dimensional network structure is 70:8:15:2.5.

[0044] Example 3

[0045] A method for preparing a wear-resistant organic composite material comprises the following steps:

[0046] Polytetrafluoroethylene, nylon (PA46), modified filler, and metal-organic framework material with a three-dimensional network structure are stirred and mixed at a stirring rate of 500 rpm for 20 minutes, dried at 70°C for 14 hours, and then extruded at a pressure of 48 MPa for 20 minutes, and then calcined. The calcination process is in an air atmosphere, starting from room temperature, and heating to 330°C at a rate of 4°C / min for 70 minutes to obtain an organic composite material;

[0047] The preparation process of the modified filler includes: stirring and mixing water and hexafluoroisopropanol, and then adding silane coupling agent (KH550), polyimide, polyethylene glycol 400, nano molybdenum disulfide, nano tungsten disulfide, nano hexagonal boron nitride, and carbon nanotubes, stirring and mixing, stirring at a rate of 600 revolutions per minute, stirring for 60 minutes, and obtaining the modified filler; the weight ratio of water to hexafluoroisopropanol is 10:3;

[0048] The weight ratio of water to silane coupling agent, polyimide, polyethylene glycol 400, nano molybdenum disulfide, nano hexagonal boron nitride, and carbon nanotube is 10:1:7:2:1:0.2:0.3;

[0049] The weight ratio of polytetrafluoroethylene, nylon, modified filler, and metal-organic framework material with a three-dimensional network structure is 80:5:12:3;

[0050] The weight ratio of nano tungsten disulfide to nano molybdenum disulfide is 1:0.5.

[0051] Comparative Example 1

[0052] Compared with Example 1, the only difference of Comparative Example 1 is that an equal amount of polyimide is used to replace the modified filler, and other raw materials and processes are the same as those of Example 1.

[0053] Comparative Example 2

[0054] Compared with Example 1, the difference of Comparative Example 2 is that an equal amount of commercially available ZIF-8 (commercially available ZIF-8 is composed of Zn ion clusters and 2-methylimidazole ligands) is used to replace the metal-organic framework material with a three-dimensional network structure in Example 1, and other raw materials and processes are the same as those in Example 1.

[0055] Comparative Example 3

[0056] Compared with Example 1, the difference of Comparative Example 3 is that the nano-molybdenum disulfide and nano-hexagonal boron nitride in Example 1 are replaced by an equal amount of graphene, and other raw materials and processes are the same as those in Example 1.

[0057] Comparative Example 4

[0058] Compared with Example 1, the difference of Comparative Example 4 is that an equal amount of propylene glycol is used to replace the hexafluoroisopropanol in Example 1, and other raw materials and processes are the same as those in Example 1.

[0059] Product effect testing

[0060] The organic composite materials prepared in the above examples and comparative examples were tested for tensile strength and wear resistance (wear resistance was measured by friction coefficient and wear scar width) according to the following methods.

[0061] Tensile strength: Referring to the method of GB / T1040.2-2006, a 1A type specimen was used, the specimen gauge length was (50.0±0.5) mm, and the tensile test was performed using a universal testing machine at a stretching rate of 50 mm / min. Five specimens were tested for each embodiment or comparative example, and the average value of the tensile strength was calculated. The results are shown in Table 1.

[0062] Friction coefficient and wear scar width: refer to the method of GB / T 3960-2016, and use a friction and wear testing machine for testing. The organic composite material prepared in the embodiment or comparative example is used as a sample and installed in the testing machine. The sample is installed above the test ring and loaded. The sample remains stationary and the test ring rotates at a certain speed.

[0063] The test ring material is 45 # Steel, HRC40-45, size outer diameter (40±0.5)mm, inner diameter 16mm, width 10mm, outer circle needs to be chamfered, the chamfer is 0.5*45°, the coaxiality deviation between the outer circle surface and the inner circle is less than 0.01mm, and the outer circle surface roughness Ra is not greater than 0.4; the test ring rotates at 200r / min, the test time is 2h, the load is 210N, and it is carried out under non-lubricated conditions. Five samples are tested in each group, and their average friction value is calculated. The results are shown in Table 1.

[0064] Table 1

[0065]

[0066] It can be seen from Table 1 that the organic composite material prepared in the embodiment of the present invention has significantly higher tensile strength and better wear resistance than that in the comparative example.

[0067] It can be further seen from Example 1 and Comparative Examples 1-4 that the present invention is selective in the type of raw materials used for the modified filler, and not all two-dimensional materials can replace the nano-molybdenum disulfide and nano-hexagonal boron nitride of the present invention. The metal-organic framework material with a three-dimensional network structure used in the present invention improves the compatibility of each component due to its unique composition and structure, so that the prepared organic composite material has good tensile strength and wear resistance. Hexafluoroisopropanol is also conducive to improving the compatibility of each component, thereby enhancing the tensile strength and wear resistance of the organic composite material.

[0068] The above content describes the basic principle and main features of the present invention and the advantages of the present invention. It should be understood by those skilled in the art that protection scope of the present invention is not limited by the above-described embodiments. Without departing from the spirit and scope of the present invention, the present invention also has various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed for protection.

Claims

1. A method for preparing an organic composite material, characterized in that: The following steps are involved: The organic composite material is obtained by mixing polytetrafluoroethylene, nylon, modified filler, and a metal-organic framework material having a three-dimensional network structure, drying, extruding, and calcining. The preparation process of the modified filler comprises: stirring and mixing water and hexafluoroisopropanol, and then adding silane coupling agent, polyimide, polyethylene glycol, nano molybdenum disulfide, nano hexagonal boron nitride and carbon nanotubes and stirring and mixing to obtain the modified filler.

2. The preparation method according to claim 1, characterized in that: The weight ratio of water to hexafluoroisopropanol is 10:(1-8).

3. The preparation method according to claim 1, characterized in that: The weight ratio of water to silane coupling agent, polyimide, polyethylene glycol, nano molybdenum disulfide, nano hexagonal boron nitride and carbon nanotube is 10: (0.5-3): (3-8): (0.5-3): (0.5-1.5): (0.1-1): (0.1-0.5).

4. The preparation method according to claim 1, characterized in that: The nylon is selected from at least one of PA46 and PA9T.

5. The preparation method according to claim 1, characterized in that: The metal-organic framework material with a three-dimensional network structure is a three-dimensional network structure comprising a combination of cobalt ions, 4,4'-di(4-pyridyl)biphenyl ligands, oxalic acid ligands and phosphotungstate anions. The molecular formula of the metal-organic framework material with a three-dimensional network structure is C 210 H 156 N 18 O 92 P2W 18 Co9.

6. The preparation method according to any one of claims 1 to 5, characterized in that: The weight ratio of the polytetrafluoroethylene, nylon, modified filler and metal-organic framework material with a three-dimensional network structure is 65-85: (5-10): (5-20): (1.5-4.5).

7. The preparation method according to any one of claims 1 to 5, characterized in that: The pressure of the extrusion molding is 30-50 MPa, and the time of the extrusion molding is 10-25 minutes.

8. The preparation method according to any one of claims 1 to 5, characterized in that: The calcination holding temperature is 220-350° C., the calcination holding time is 60-80 minutes, and the heating temperature during calcination is started from room temperature and heated at a rate of 3-8° C. / minute.

9. An organic composite material, characterized in that: The invention is prepared by the preparation method according to any one of claims 1 to 8.

10. A device, characterized in that: The organic composite material comprises the organic composite material prepared by the preparation method according to any one of claims 1 to 8 or the organic composite material according to claim 9.

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