CN110028788B - Polyimide composite material, porous polyimide retainer, preparation method of porous polyimide retainer and bearing - Google Patents
Polyimide composite material, porous polyimide retainer, preparation method of porous polyimide retainer and bearing Download PDFInfo
- Publication number
- CN110028788B CN110028788B CN201810027153.3A CN201810027153A CN110028788B CN 110028788 B CN110028788 B CN 110028788B CN 201810027153 A CN201810027153 A CN 201810027153A CN 110028788 B CN110028788 B CN 110028788B
- Authority
- CN
- China
- Prior art keywords
- polyimide
- retainer
- porous
- molding powder
- porous polyimide
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 229920001721 polyimide Polymers 0.000 title claims abstract description 234
- 239000004642 Polyimide Substances 0.000 title claims abstract description 233
- 239000002131 composite material Substances 0.000 title claims abstract description 26
- 238000002360 preparation method Methods 0.000 title claims abstract description 15
- 229920006259 thermoplastic polyimide Polymers 0.000 claims abstract description 28
- -1 ketone anhydride Chemical class 0.000 claims abstract description 22
- RTZKZFJDLAIYFH-UHFFFAOYSA-N ether Substances CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 claims abstract description 9
- 238000000465 moulding Methods 0.000 claims description 96
- 239000000843 powder Substances 0.000 claims description 84
- 239000000203 mixture Substances 0.000 claims description 30
- 238000001035 drying Methods 0.000 claims description 23
- 238000000034 method Methods 0.000 claims description 16
- 239000002994 raw material Substances 0.000 claims description 9
- 238000011049 filling Methods 0.000 claims description 7
- 238000002156 mixing Methods 0.000 claims description 3
- 230000001105 regulatory effect Effects 0.000 claims description 2
- 238000004519 manufacturing process Methods 0.000 claims 2
- 230000001276 controlling effect Effects 0.000 claims 1
- 238000005461 lubrication Methods 0.000 abstract description 5
- 230000007774 longterm Effects 0.000 abstract description 4
- 238000010521 absorption reaction Methods 0.000 abstract description 3
- 239000010687 lubricating oil Substances 0.000 abstract description 3
- 238000003756 stirring Methods 0.000 description 26
- 150000008064 anhydrides Chemical class 0.000 description 18
- 238000001816 cooling Methods 0.000 description 14
- 239000000463 material Substances 0.000 description 12
- 239000011148 porous material Substances 0.000 description 10
- 238000007789 sealing Methods 0.000 description 10
- 238000007873 sieving Methods 0.000 description 10
- 238000003825 pressing Methods 0.000 description 5
- 238000007796 conventional method Methods 0.000 description 4
- 238000010438 heat treatment Methods 0.000 description 4
- 230000009286 beneficial effect Effects 0.000 description 2
- 239000006185 dispersion Substances 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 238000005245 sintering Methods 0.000 description 2
- 101000731924 Saccharomyces cerevisiae (strain ATCC 204508 / S288c) 40S ribosomal protein S27-A Proteins 0.000 description 1
- 101000731894 Saccharomyces cerevisiae (strain ATCC 204508 / S288c) 40S ribosomal protein S27-B Proteins 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000001513 hot isostatic pressing Methods 0.000 description 1
- 238000011068 loading method Methods 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 229920003002 synthetic resin Polymers 0.000 description 1
- 238000001291 vacuum drying Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
- B29B7/00—Mixing; Kneading
- B29B7/002—Methods
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C43/00—Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor
- B29C43/003—Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor characterised by the choice of material
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C43/00—Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor
- B29C43/02—Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor of articles of definite length, i.e. discrete articles
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L79/00—Compositions of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing nitrogen with or without oxygen or carbon only, not provided for in groups C08L61/00 - C08L77/00
- C08L79/04—Polycondensates having nitrogen-containing heterocyclic rings in the main chain; Polyhydrazides; Polyamide acids or similar polyimide precursors
- C08L79/08—Polyimides; Polyester-imides; Polyamide-imides; Polyamide acids or similar polyimide precursors
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2201/00—Properties
- C08L2201/08—Stabilised against heat, light or radiation or oxydation
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2205/00—Polymer mixtures characterised by other features
- C08L2205/02—Polymer mixtures characterised by other features containing two or more polymers of the same C08L -group
- C08L2205/025—Polymer mixtures characterised by other features containing two or more polymers of the same C08L -group containing two or more polymers of the same hierarchy C08L, and differing only in parameters such as density, comonomer content, molecular weight, structure
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Rolling Contact Bearings (AREA)
- Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)
- Casting Or Compression Moulding Of Plastics Or The Like (AREA)
Abstract
The invention relates to a polyimide composite material, a porous polyimide retainer, a preparation method of the porous polyimide retainer and a bearing. The polyimide composite material mainly comprises the following components in percentage by mass: 55-85% of pyromellitic polyimide and 15-45% of thermoplastic polyimide; the thermoplastic polyimide is at least one of ketone anhydride type polyimide and ether anhydride type polyimide. The polyimide composite material is compounded by the pyromellitic polyimide and the thermoplastic polyimide which have high hardness, strong rigidity and infusibility, so that when the composite material is used for preparing the porous polyimide retainer, the porous polyimide retainer can improve the high tensile strength, the high hardness, the high wear resistance and the good temperature resistance of the porous polyimide retainer, reduce the aperture and the thermal expansion coefficient of the porous polyimide retainer, facilitate the release and absorption of lubricating oil, facilitate the long-term lubrication of a bearing, and can be widely applied to the field of long-life momentum bearing retainers.
Description
Technical Field
The invention relates to a polyimide composite material, a porous polyimide retainer, a preparation method of the porous polyimide retainer and a bearing, and belongs to the technical field of polyimide composite materials.
Background
The porous polyimide retainer has the advantages of high tensile strength, good chemical stability, excellent tribology performance, good space environment resistance and the like, provides long-term, good and continuous oil lubrication in the use process, and is widely applied to long-life momentum wheel bearings with special requirements on high precision, continuous lubrication and the like.
With the further improvement of the host client on the requirements of the momentum wheel bearing on the service life and reliability, the existing porous polyimide material cannot meet the requirements on the indexes such as pore diameter, narrowing control and wear resistance, and becomes one of the main bottlenecks limiting the service life and reliability of the momentum wheel bearing increasingly, and a porous polyimide material with excellent performance is urgently needed.
In the prior art, to
9000 polyimide material is used as raw material, and hot isostatic pressing process is adopted, so that porous polyimide retainer with small pore diameter and good wear resistance and temperature resistance can be obtained, and the porous polyimide retainer with the best performance in the world is obtained. The domestic porous polyimide retainer is mainly prepared by taking thermoplastic polyimide as a raw material and adopting a constant volume process or a limiting pressing process, and the porous polyimide retainer prepared by adopting the material has the advantages of difficult control of pore diameter, large dispersion and difficulty in meeting the requirement of long service life of a bearing.
At present, there are many methods for preparing a porous polyimide retainer, and for example, a chinese patent with an issued publication number of CN103507193B discloses a preheating, limiting and pressing process for a porous polyimide composite retainer tube blank, the pressing process includes the steps of firstly, performing vacuum drying treatment on raw material polyimide, preparing a polyimide mixture according to a weight ratio, loading the mixture into a mold, performing constant temperature treatment, then, quickly taking out the mixture, performing limiting and pressurizing, maintaining pressure, demolding, and then, placing the mixture into a program-controlled sintering furnace for sintering and molding. The porous polyimide composite retainer tube blank prepared by the pressing process has wide adjustable ranges of density, pore radius and porosity. However, due to the technical process, the diameter of the hole of the retainer tube blank material prepared by the method is difficult to stably control to 1.0 μm, the dispersion of the hole diameter is large, and the wear resistance is relatively poor.
Disclosure of Invention
The invention aims to provide a polyimide composite material, which can improve the wear resistance and the temperature resistance of a porous polyimide retainer, reduce the pore diameter of the porous polyimide material, realize narrowing control and lay a material foundation for realizing the long service life of a bearing.
The invention also provides a porous polyimide retainer, a preparation method thereof and a bearing adopting the porous polyimide retainer.
In order to achieve the above object, the polyimide composite material of the present invention adopts the following technical scheme:
a polyimide composite material mainly comprises the following components in percentage by mass: 55-85% of pyromellitic polyimide and 15-45% of thermoplastic polyimide; the thermoplastic polyimide is at least one of ether anhydride type polyimide and ketone anhydride type polyimide.
The polyimide composite material is compounded by the pyromellitic polyimide and the thermoplastic polyimide which have high hardness, strong rigidity and infusibility, so that when the composite material is used for preparing the porous polyimide retainer, the tensile strength, the hardness, the wear resistance and the good temperature resistance of the porous polyimide retainer can be improved, the pore diameter of the porous polyimide retainer is reduced, the pore diameter distribution interval is narrowed, the thermal expansion coefficient is reduced, the release and the absorption of lubricating oil are facilitated, the long-term lubrication of a bearing is facilitated, and the composite material can be widely applied to the field of long-life momentum bearing retainers.
The mesh number of the pyromellitic polyimide is not less than 400 meshes, and the mesh number of the thermoplastic polyimide is not less than 400 meshes. The mesh number of not less than 400 means that the minimum mesh number of a screen through which the polyimide can pass is 400 mesh.
The ether anhydride type polyimide is at least one of monoether type polyimide and diether type polyimide.
The porous polyimide retainer adopts the technical scheme that:
a porous polyimide retainer is mainly prepared from the following raw materials in percentage by mass: 55-85% of pyromellitic polyimide and 15-45% of thermoplastic polyimide; the thermoplastic polyimide is at least one of ether anhydride type polyimide and ketone anhydride type polyimide.
The porous polyimide retainer has the advantages of high annular tensile strength, small pore diameter, good wear resistance, high hardness, small thermal expansion coefficient, good heat resistance and the like.
The porosity of the porous polyimide retainer is 10-30%.
The ether anhydride type polyimide is at least one of monoether type polyimide and diether type polyimide.
The preparation method of the porous polyimide retainer adopts the technical scheme that:
the preparation method of the porous polyimide retainer comprises the following steps: uniformly mixing the pyromellitic polyimide molding powder and the thermoplastic polyimide molding powder according to the formula ratio to obtain a polyimide mixture, and then carrying out hot press molding on the polyimide mixture to obtain the polyimide composite material.
The preparation method of the porous polyimide retainer has simple process, narrows the distribution range of the product pore diameter while improving the wear resistance and the temperature resistance of the porous polyimide retainer, has low cost and is convenient for popularization and application.
The mesh number of the pyromellitic polyimide molding powder is not less than 400 meshes, and the mesh number of the thermoplastic polyimide molding powder is not less than 400 meshes. The pyromellitic polyimide molding powder and the thermoplastic polyimide molding powder with the mesh number of not less than 400 can be obtained by sieving through a sieve with the mesh number of not less than 400 (such as 500 meshes, 600 meshes and the like) and taking the undersize.
The pressure of the hot-press molding is 900-1100 kg/cm2. The hot-press forming temperature is 350-400 ℃. The hot-press forming time is 30-60 min.
Before hot press molding, the polyimide mixture is filled into the holder mold, and the porosity of the porous polyimide holder is regulated and controlled by adjusting the density of the porous polyimide holder. Calculating the density of the porous polyimide retainer according to the porosity required by the porous polyimide retainer, and determining the quality of a polyimide mixture required by the preparation of the corresponding porous polyimide retainer by combining the inner diameter, the outer diameter and the height of the porous polyimide retainer.
The retainer die comprises an outer sleeve, a mandrel, a punch and a base, wherein the outer sleeve, the mandrel and the base form a retainer die cavity. Setting the inner diameter of the retainer as D, the outer diameter as D and the height as H, wherein the inner diameter of the outer sleeve is equal to the outer diameter D +3mm, the outer diameter of the mandrel is equal to the inner diameter D-3mm, and the height of the outer sleeve is equal to or more than 3H. The outer diameter of the punch is matched with the inner diameter of the outer sleeve, the inner diameter of the punch is matched with the outer diameter of the mandrel, the inner diameter of the base is matched with the outer diameter of the mandrel, and the outer diameter of the base is matched with the inner diameter of the outer sleeve.
Filling the required amount of polyimide mixture into a retainer die, closing the die, and adding a limit block with a certain height on a die mandrel, so that hBase seat+H+hPunch head＝hCore shaft+hLimiting positionAnd then hot press molding is performed.
The hot press forming is performed on a programmable hot press. The temperature control precision of the programmable hot press is +/-1 ℃.
The hot press molding is to pressurize the polyimide mixture to 900-1100 kg/cm2And then maintaining the pressure, raising the temperature to 350-400 ℃ while maintaining the pressure, and maintaining the temperature at 350-400 ℃ and maintaining the pressure for 30-60 min. The time for raising the temperature is not shorter than 60 min. Preferably, the temperature rise time is 60-80 min.
And after hot press molding, demolding when the temperature of the retainer mold is lower than 240 ℃.
Before the pyromellitic polyimide molding powder and the thermoplastic polyimide molding powder are mixed, the pyromellitic polyimide molding powder is dried for 1-4 hours at 200-240 ℃.
Before the pyromellitic polyimide molding powder and the thermoplastic polyimide molding powder are mixed, the thermoplastic polyimide molding powder is dried for 1-4 hours at the temperature of 120-180 ℃.
The drying of the homopolyphenylene polyimide and the thermoplastic polyimide is carried out in a drying oven. After drying, cooling to room temperature.
The pyromellitic polyimide molding powder and the thermoplastic polyimide molding powder can be mixed uniformly by the following method: putting the pyromellitic polyimide molding powder and the thermoplastic polyimide molding powder into a mechanical stirrer together to stir for 3-5 times, wherein the stirring time is controlled to be 20-30 s each time, and the rotating speed of the mechanical stirrer is controlled to be 10000-12000 r/min each time of stirring. Judging whether the pyromellitic polyimide molding powder and the thermoplastic polyimide molding powder in the polyimide composite material are mixed uniformly or not, observing the color difference of the polyimide composite material by using a microscope, and obtaining the uniformly mixed polyimide composite material without obvious color difference. For example, regarding the homopolyphenylene polyimide molding powder and the thermoplastic polyimide molding powder having a mesh number of not less than 400 mesh, twenty times or forty times microscope observation can be used to judge whether or not they are mixed. The pyromellitic polyimide molding powder is light yellow, the monoether anhydride polyimide is bright yellow, the diether anhydride polyimide is grayish gray, and the ketone anhydride type polyimide is light yellow in the thermoplastic polyimide molding powder.
And before hot press molding, sealing and storing the polyimide mixture.
The technical scheme adopted by the bearing of the invention is as follows:
a bearing using the porous polyimide retainer.
The bearing provided by the invention adopts the polyimide retainer, and has the advantages of light weight, high hardness, good wear resistance and temperature resistance and long service life.
Detailed Description
The technical solution of the present invention will be further described with reference to the following embodiments.
The pyromellitic polyimide molding powder, the mono-ether anhydride type polyimide molding powder, the di-ether anhydride type polyimide molding powder and the ketone anhydride type polyimide molding powder used in the embodiment are all commercially available products, wherein: the number of the pyromellitic polyimide molding powder is P84NT2, and the powder is purchased from winning industry group; the monoether anhydride type polyimide molding powder is the grade YS20 and is purchased from Shanghai research institute of synthetic resin; the grade of the bi-ether anhydride type polyimide molding powder is HI-P-100, which is purchased from Nakawasaki polyimide materials Co.Ltd; the ketone anhydride type polyimide molding powder is available from the winning industry group under the brand number P84NT 1.
The inner diameter D of the porous polyimide retainer is 28.2mm, the outer diameter D of the porous polyimide retainer is 35.6mm, and the height H of the porous polyimide retainer is 6.6 mm; the equipment adopted by the hot-press molding is a programmable hot press, and the temperature control precision is +/-1 ℃.
The retainer die adopted by the hot-press forming comprises an outer sleeve, a mandrel, a punch and a base, wherein the outer sleeve, the mandrel and the base form a retainer die cavity. The inner diameter of the outer sleeve of the retainer die is 38.6mm which is the outer diameter D +3mm of the retainer, and the outer diameter of the mandrel is 38.6mm which is the outer diameter of the retainerThe inner diameter d-3mm is 25.2mm, the height H of the retainer, which is equal to or more than 3 times of the height of the mandrel, of the outer sleeve is 19.8mm, the outer diameter of the punch is matched with the inner diameter of the outer sleeve, the inner diameter of the punch is matched with the outer diameter of the mandrel, the inner diameter of the base is matched with the outer diameter of the mandrel, and the outer diameter of the base is matched with the inner diameter of the outer sleeve. The mandrel is provided with a limiting block for limiting the lowest position of the punch in a downward pressing manner, and the height h of the limiting blockLimiting positionThe calculation can be made according to the following formula: h isLimiting position＝H+hBase seat+hPunch head-hCore shaft. In the hot-press molding process, when the punch head is pressed down to contact with the limiting block, the height of the die cavity of the retainer is consistent with that of the porous polyimide retainer.
The quality of the polyimide compound used to prepare the porous polyimide retainer in each example can be determined with reference to the following method: the theoretical density ρ ═ ρ of the porous polyimide holder was calculated assuming that the porosity of the porous polyimide holder was 15% and the wall thickness was 10mmEntityX (1-15%); wherein,
or
m1Is the mass percentage of the pyromellitic polyimide; other cases can be calculated by referring to the above method; then, the volume V ═ pi (D) of the porous polyimide retainer was calculated from the dimensions of the height h, the inner diameter D, and the outer diameter D of the retainer as set2-d2) And/4 × h, and finally obtaining the polyimide mixture with the mass m ═ ρ V required by the preparation of the porous polyimide retainer.
Example 1
The polyimide composite material of the embodiment comprises the following components in percentage by mass: 70% of pyromellitic polyimide molding powder and 30% of monoether anhydride type polyimide molding powder.
The porous polyimide retainer of the embodiment is prepared from the following raw materials in percentage by mass: 70% of pyromellitic polyimide molding powder and 30% of monoether anhydride type polyimide molding powder; the porosity of the porous polyimide holder was 20%.
The preparation method of the porous polyimide retainer of the embodiment comprises the following steps:
1) putting the pyromellitic polyimide molding powder into a drying oven, drying for 2h at 240 ℃, cooling to room temperature, then sieving with a 400-mesh sieve, and sealing and storing the undersize for later use;
putting the monoether anhydride type polyimide molding powder into a drying oven, drying for 2h at 150 ℃, cooling to room temperature, then sieving with a 400-mesh sieve, and sealing and storing the undersize for later use;
2) respectively putting the prepared amounts of the pyromellitic polyimide molding powder and the monoether anhydride type polyimide molding powder into a mechanical stirrer to stir for 3 times from the pyromellitic polyimide molding powder and the monoether anhydride type polyimide molding powder which are stored in a sealed way, wherein the stirring time is 30s each time, and the stirring rotating speed is 12000r/min each time; after each stirring, observing the color difference of the mixture by using a forty-fold microscope, wherein the color difference is more obvious after the first two times of stirring, and the polyimide mixture without obvious color difference is obtained after the third time of stirring;
3) filling the obtained polyimide mixture into a mold cavity of the retainer, closing the mold, setting the porosity of the porous polyimide retainer to be 20%, calculating the height of the limiting block, placing the limiting block into the mold, transferring the mold of the retainer to a programmable hot press, and pressurizing to 1000kg/cm2And then starting a heating program, heating to 375 ℃ after 80min, then preserving heat for 30min, releasing pressure, taking out the retainer mold, naturally cooling, and demolding when the temperature is lower than 240 ℃ to obtain the material.
The bearing of this example was produced by a conventional method using the porous polyimide holder of this example.
Example 2
The polyimide composite material of the embodiment comprises the following components in percentage by mass: 55% of pyromellitic polyimide molding powder and 45% of diether anhydride type polyimide molding powder.
The porous polyimide retainer of the embodiment is prepared from the following raw materials in percentage by mass: 55% of pyromellitic polyimide molding powder and 45% of diether anhydride type polyimide molding powder; the porosity of the porous polyimide holder was 10%.
The preparation method of the porous polyimide retainer of the embodiment comprises the following steps:
1) putting the pyromellitic polyimide molding powder into a drying oven, drying for 1h at 240 ℃, cooling to room temperature, then sieving with a 400-mesh sieve, and sealing and storing the undersize for later use;
putting the diether anhydride type polyimide molding powder into a drying oven, drying for 1h at 180 ℃, cooling to room temperature, then sieving with a 400-mesh sieve, and sealing and storing undersize for later use;
2) respectively putting the prepared amounts of the pyromellitic polyimide molding powder and the diether anhydride type polyimide molding powder into a mechanical stirrer to stir for 3 times from the pyromellitic polyimide molding powder and the diether anhydride type polyimide molding powder which are stored in a sealed way, wherein the stirring time is 30s each time, and the stirring speed is 12000r/min each time; after each stirring, observing the color difference of the mixture by using a forty-fold microscope, wherein the color difference is more obvious after the first two times of stirring, and the polyimide mixture without obvious color difference is obtained after the third time of stirring;
3) filling the obtained polyimide mixture into a mold cavity of the retainer, closing the mold, setting the porosity of the porous polyimide retainer to be 10%, calculating the height of the limiting block, putting the limiting block into the mold, transferring the mold of the retainer into a programmable hot press, and pressurizing to 900kg/cm2And then starting a heating program, heating to 350 ℃ after 70min, then preserving heat for 60min, releasing pressure, taking out the retainer mold, naturally cooling, and demolding when the temperature is lower than 240 ℃ to obtain the material.
The bearing of this example was produced by a conventional method using the porous polyimide holder of this example.
Example 3
The polyimide composite material of the embodiment comprises the following components in percentage by mass: 85% of pyromellitic polyimide molding powder and 15% of ketone anhydride type polyimide molding powder.
The porous polyimide retainer of the embodiment is prepared from the following raw materials in percentage by mass: 85% of pyromellitic polyimide molding powder and 15% of ketone anhydride type polyimide molding powder; the porosity of the porous polyimide holder was 28%.
The preparation method of the porous polyimide retainer of the embodiment comprises the following steps:
1) putting the pyromellitic polyimide molding powder into a drying oven, drying for 4h at 200 ℃, cooling to room temperature, then sieving with a 400-mesh sieve, and sealing and storing the undersize for later use;
putting the ketone anhydride type polyimide molding powder into a drying oven, drying for 4h at 120 ℃, cooling to room temperature, then sieving with a 400-mesh sieve, and sealing and storing the undersize for later use;
2) respectively putting the prepared amounts of the pyromellitic polyimide molding powder and the ketone anhydride type polyimide molding powder into a mechanical stirrer to be stirred for 5 times from the sealed and stored pyromellitic polyimide molding powder and the sealed and stored ketone anhydride type polyimide molding powder, wherein the stirring time is 20s each time, and the stirring speed is 10000r/min each time;
observing the color difference of the mixture by using a forty-fold microscope after each stirring is finished, wherein the color difference is obvious after the first four times of stirring, and the polyimide mixture without obvious color difference is obtained after the fifth stirring;
3) filling the obtained polyimide mixture into a mold cavity of the retainer, closing the mold, setting the porosity of the porous polyimide retainer to be 28%, calculating the height of the limiting block, placing the limiting block into the mold, transferring the mold of the retainer into a programmable hot press, and pressurizing to 1100kg/cm2And then starting a heating program, heating to 400 ℃ after 65min, then preserving heat for 45min, releasing pressure, taking out the retainer mold, naturally cooling, and demolding when the temperature is lower than 240 ℃ to obtain the material.
The bearing of this example was produced by a conventional method using the porous polyimide holder of this example.
Example 4
The polyimide composite material comprises the following components in percentage by mass: 65% of pyromellitic polyimide molding powder, 20% of ketone anhydride type polyimide molding powder and 15% of monoether anhydride type polyimide molding powder.
The porous polyimide retainer of the embodiment is prepared from the following raw materials in percentage by mass: 65% of pyromellitic polyimide molding powder, 20% of ketone anhydride type polyimide molding powder and 15% of monoether anhydride type polyimide molding powder; the porosity of the polyimide cage was 20%.
The preparation method of the porous polyimide retainer of the embodiment comprises the following steps:
1) putting the pyromellitic polyimide molding powder into a drying oven, drying for 2h at 240 ℃, cooling to room temperature, then sieving with a 400-mesh sieve, and sealing and storing the undersize for later use;
putting the ketone anhydride type polyimide molding powder into a drying oven, drying for 2h at 150 ℃, cooling to room temperature, then sieving with a 400-mesh sieve, and sealing and storing the undersize for later use;
putting the monoether anhydride type polyimide molding powder into a drying oven, drying for 2h at 150 ℃, cooling to room temperature, then sieving with a 400-mesh sieve, and sealing and storing the undersize for later use;
2) respectively putting the prepared amounts of the pyromellitic polyimide molding powder, the ketone anhydride type polyimide molding powder and the monoether anhydride type polyimide molding powder into a mechanical stirrer to stir for 3 times from the pyromellitic polyimide molding powder, the ketone anhydride type polyimide molding powder and the monoether anhydride type polyimide molding powder which are stored in a sealed way, wherein the stirring time is 30s each time, and the stirring speed is 12000r/min each time; after each stirring, observing the color difference of the mixture by using a forty-fold microscope, wherein the color difference is more obvious after the first two times of stirring, and the polyimide mixture without obvious color difference is obtained after the third time of stirring;
3) filling the obtained polyimide mixture into a mold cavity of the retainer, closing the mold, setting the porosity of the porous polyimide retainer to be 20%, calculating the height of the limiting block, placing the limiting block into the mold, transferring the mold of the retainer to a programmable hot press, and pressurizing to 1000kg/cm2Then starting a heating program, heating to 375 ℃ for 80min, then preserving heat for 30min, releasing pressure, taking out and preserving heatNaturally cooling the holder mold, and demolding when the temperature is lower than 200 ℃ to obtain the product.
The bearing of this example was produced by a conventional method using the porous polyimide holder of this example.
The porous polyimide holders of examples 1 to 4 and
the performance of the 9000 porous polyimide cages were compared as shown in table 1.
TABLE 1 porous polyimide holders and porous polyimide films of examples 1 to 4
9000 cage Performance comparison
As can be seen from the data in Table 1, the porous polyimide retainer materials of examples 1-4 have pore diameters of 0.7-1.4 μm, greatly improved wear resistance, higher annular tensile strength, high hardness, small thermal expansion coefficient, good heat resistance and the like, and have the best performance in the world
The 9000 porous polyimide cage performs comparably.
The polyimide composite material has the characteristics of high annular tensile strength, high hardness, small thermal expansion coefficient, good heat resistance and the like, and can be used as a long-life bearing retainer; the porous polyimide retainer has small hole diameter, is beneficial to the release and absorption of lubricating oil, greatly improves the wear resistance, is beneficial to the long-term lubrication of the bearing, and can be widely applied to the field of long-life momentum wheel bearings.
Claims (3)
1. A preparation method of a porous polyimide retainer is characterized by comprising the following steps: the method comprises the following steps: uniformly mixing the formula amount of the pyromellitic polyimide molding powder and the formula amount of the thermoplastic polyimide molding powder to obtain a polyimide mixture, then carrying out hot press molding on the polyimide mixture, and then carrying out demoulding treatment to obtain the polyimide composite material;
the mesh number of the pyromellitic polyimide molding powder is not less than 400 meshes, and the mesh number of the thermoplastic polyimide molding powder is not less than 400 meshes;
the porous polyimide retainer is mainly prepared from the following raw materials in percentage by mass: 55-85% of pyromellitic polyimide and 15-45% of thermoplastic polyimide; the thermoplastic polyimide is ether anhydride type polyimide;
before hot press molding, filling a polyimide mixture into a holder mold, regulating and controlling the porosity of a porous polyimide holder by adjusting the density of the porous polyimide holder, calculating the density of the porous polyimide holder according to the porosity required by the porous polyimide holder, and determining the quality of the polyimide mixture required by preparing the corresponding porous polyimide holder by combining the inner diameter, the outer diameter and the height of the porous polyimide holder;
the retainer die comprises an outer sleeve, a mandrel, a punch and a base, wherein the outer sleeve, the mandrel and the base form a retainer die cavity; filling the required amount of polyimide mixture into a retainer die, closing the die, and adding a limit block with a certain height on a die mandrel, so that hBase seat+HHolding rack+hPunch head=hCore shaft+hLimiting positionThen hot-press forming is carried out;
the hot press molding is to pressurize the polyimide mixture to 900-1100 kg/cm2And then maintaining the pressure, raising the temperature to 350-400 ℃ while maintaining the pressure, and maintaining the temperature at 350-400 ℃ and maintaining the pressure for 30-60 min.
2. The method for producing a porous polyimide holder according to claim 1, characterized in that: the porosity of the porous polyimide retainer is 10-30%.
3. The method for producing a porous polyimide holder according to claim 1, characterized in that: before mixing the pyromellitic polyimide molding powder and the thermoplastic polyimide molding powder, drying the pyromellitic polyimide molding powder at 200-240 ℃ for 1-4 h, and drying the thermoplastic polyimide molding powder at 120-180 ℃ for 1-4 h.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810027153.3A CN110028788B (en) | 2018-01-11 | 2018-01-11 | Polyimide composite material, porous polyimide retainer, preparation method of porous polyimide retainer and bearing |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810027153.3A CN110028788B (en) | 2018-01-11 | 2018-01-11 | Polyimide composite material, porous polyimide retainer, preparation method of porous polyimide retainer and bearing |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110028788A CN110028788A (en) | 2019-07-19 |
| CN110028788B true CN110028788B (en) | 2021-11-26 |
Family
ID=67234675
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810027153.3A Active CN110028788B (en) | 2018-01-11 | 2018-01-11 | Polyimide composite material, porous polyimide retainer, preparation method of porous polyimide retainer and bearing |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110028788B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113510891B (en) * | 2021-04-23 | 2022-09-27 | 中国科学院兰州化学物理研究所 | Two-stage hole polyimide material, preparation method thereof, two-stage hole polyimide retainer and application thereof |
| CN113147105A (en) * | 2021-04-23 | 2021-07-23 | 中国科学院兰州化学物理研究所 | Porous polyimide oil storage and retention structure and preparation method and application thereof |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5939498A (en) * | 1998-04-07 | 1999-08-17 | E. I. Du Pont De Nemours And Company | High modulus polyimide blend |
| JP3708348B2 (en) * | 1998-12-24 | 2005-10-19 | 三井化学株式会社 | Polyimide resin composition |
| DE102005034969A1 (en) * | 2005-07-22 | 2007-02-08 | Inspec Fibres Gmbh | Process for the preparation of a block copolymer of polyimides and use of the block copolymer for the production of powders and moldings |
| CN100462403C (en) * | 2006-07-24 | 2009-02-18 | 海洋化工研究院 | Blend of polyimide polymer and its use as high temperature resisting dipping glue |
| JP4680288B2 (en) * | 2008-10-10 | 2011-05-11 | トヨタ自動車株式会社 | Friction material and friction material manufacturing method |
| CN101456967B (en) * | 2009-01-05 | 2011-10-12 | 中国工程物理研究院化工材料研究所 | Method for preparing thermoplastic polyimide porous material |
| CN103160124B (en) * | 2013-02-26 | 2015-01-28 | 洛阳轴研科技股份有限公司 | Method for producing holder blank with ether anhydride type polyimide molding powder composite material |
| CN103507193B (en) * | 2013-10-15 | 2015-11-18 | 洛阳轴研科技股份有限公司 | Porous polyimide composite holder pipe preheats spacing pressing process |
| CN103756313B (en) * | 2013-12-13 | 2017-01-11 | 洛阳轴研科技股份有限公司 | Method used for increasing hear resistance of ketone-anhydride type polyimide retainer tube blank |
-
2018
- 2018-01-11 CN CN201810027153.3A patent/CN110028788B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN110028788A (en) | 2019-07-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110028788B (en) | Polyimide composite material, porous polyimide retainer, preparation method of porous polyimide retainer and bearing | |
| CN111763429B (en) | Porous polyimide composite material for bearing retainer, preparation method of porous polyimide composite material and bearing retainer | |
| CN105061956B (en) | A kind of polyether-ether-ketone modified polytetrafluoroethylcomposite composite material, retainer and preparation method thereof | |
| CN111170756B (en) | Preparation method of revolving body carbon/carbon composite material | |
| CN102828096B (en) | Metal ceramic cutting tool material and preparation method thereof | |
| CN113953512B (en) | Large length-diameter ratio deep-hole thin-wall tungsten alloy shell and hot isostatic pressing preparation method thereof | |
| CN104987630A (en) | Modified polytrifluorochloroethylene and molding process thereof | |
| CN106041047A (en) | Powder metallurgy high-strength bearing material and preparation method thereof | |
| CN109808114B (en) | Preparation method of bearing retainer material and preparation method of bearing retainer | |
| CN105154731A (en) | Aluminum base antiwear composite material and preparation method thereof | |
| CN103756313A (en) | Method used for increasing hear resistance of ketone-anhydride type polyimide retainer tube blank | |
| CN1321791C (en) | Material of porous polyimide holder and molding technique | |
| CN112658266A (en) | Pore characteristic light gradient material and application thereof | |
| CN113002004A (en) | Preparation method of modified polytetrafluoroethylene self-lubricating composite material | |
| CN104496498B (en) | A kind of preparation method of bottom casting train wheel graphite jig | |
| CN113290759A (en) | Forming method of small-size polyimide self-lubricating composite retainer material | |
| CN108620574B (en) | Forming agent, feed and preparation method thereof, green body and preparation method thereof | |
| CN112276075B (en) | Binder for metal powder injection molding and preparation method and application thereof | |
| CN110313233B (en) | A kind of manufacturing process of WCu cavity liner | |
| CN103507193B (en) | Porous polyimide composite holder pipe preheats spacing pressing process | |
| CN103305001A (en) | Manufacturing method of ketone-anhydride type polyimide composite retainer tube blank | |
| CN113563626A (en) | Method for manufacturing polyimide holder material | |
| CN110421866B (en) | Polyimide material, polyimide retainer and preparation method thereof | |
| CN118855862A (en) | Porous polyimide retainer material with gradient pore structure, preparation method thereof and bearing | |
| CN110016229B (en) | Low-oil-outlet-rate microporous core valve material and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |