JP2018162411A - Polyimide resin composition, and seal ring - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition that possesses a specific flexural modulus, and is excellent in slidability with a soft metal as a counterpart material (for example, aluminum, copper, zinc or the like) as well as excellent in the wear resistance of the resin composition itself.SOLUTION: A polyimide resin composition contains a thermoplastic polyimide resin 50 pts.mass-98 pts.mass, a phenolic resin carbon fiber 1 pt.mass-40 pts.mass, and a fluorine resin 1 pt.mass-10 pts.mass and has a flexural modulus of 3000 MPa-7000 MPa.SELECTED DRAWING: None

Description

  The present disclosure relates to a polyimide resin composition and a seal ring.

  In recent years, materials such as rotating bodies and housings used for automobile parts, industrial parts, office equipment and the like have been reduced in weight in order to reduce energy loss and improve exercise efficiency. For this reason, weight reduction is achieved by various parts. Metals used for structural bodies, rotating bodies, and the like have been replaced by materials having a light weight and excellent strength (for example, soft metals such as aluminum) from materials such as carbon steel and stainless steel.

  Since the heat-resistant resin material has excellent characteristics such as heat resistance and self-lubricating property, it is often used for sliding portions with various metal members. Therefore, a sliding member formed using a resin composition using a heat-resistant resin as a material has been developed in accordance with use conditions (for example, see Patent Document 1).

JP 2007-192242 A

When the mating material of the sliding member made of the resin composition is a metal member made of soft metal (aluminum, copper, zinc, etc.), the amount of self-wearing of the resin composition is small, and the amount of wear of the mating material is small. Desired.
However, the sliding member made of the resin composition may attack the metal member that is the counterpart material (wear the counterpart material). Therefore, the resin composition applied to the sliding member achieves both the wear resistance of the resin composition itself (own material) and the low aggressiveness against the metal which is the counterpart material (the friction wear characteristic of the counterpart material is good). Therefore, further improvement is required.

  The present disclosure has been made in view of the above circumstances, and an object of the present disclosure is to possess a specific bending elastic modulus and to be slidable with a soft metal (for example, aluminum, copper, zinc, etc.) that is a counterpart material. Another object of the present invention is to provide a resin composition excellent in wear resistance of the resin composition itself.

  As a result of intensive studies to achieve the above-mentioned problems, the inventors of the present invention have made a resin composition containing a specific amount of a thermoplastic polyimide resin, a phenol resin carbon fiber, and a fluororesin, and this resin composition. It was found that the above problem can be solved by controlling the flexural modulus of the resin to a range of 3000 MPa to 7000 MPa.

  That is, the following aspects are included in the means for solving the above problems.

<1> 50 to 98 parts by mass of a thermoplastic polyimide resin, 1 to 40 parts by mass of a phenol resin carbon fiber, and 1 to 10 parts by mass of a fluororesin, and a flexural modulus of 3000 MPa to A polyimide resin composition having a pressure of 7000 MPa.

<2> The polyimide resin composition according to <1>, wherein the thermoplastic polyimide resin is a thermoplastic polyimide resin having a repeating structural unit represented by the following chemical formula (1).

In the chemical formula (1), X represents a direct bond, —SO ₂ —, —CO—, —C (CH ₃ ) ₂ —, —C (CF ₃ ) ₂ —, or —S—, and R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom, an alkyl group, an alkoxy group, a halogenated alkyl group, a halogenated alkoxy group, or a halogen atom, and Y represents (A) in the following chemical formula (2), A group selected from the group consisting of (B), (C), and (D) is shown.

<3> The polyimide resin composition according to <1>, wherein the thermoplastic polyimide resin is a thermoplastic polyimide resin having a repeating structural unit represented by the following chemical formula (3).

<4> The polyimide resin composition according to <1>, wherein the thermoplastic polyimide resin is a thermoplastic polyimide resin having a repeating structural unit represented by the following chemical formula (4) and the following chemical formula (5).

  However, m and n are the molar ratio of a copolymer, and show the range of m / n = 4 mol-99 mol.

<5> The polyimide resin composition according to <1>, wherein the thermoplastic polyimide resin is a thermoplastic polyimide resin having a repeating structural unit represented by the following chemical formula (6).

<6> A seal ring obtained by molding the polyimide resin composition according to any one of <1> to <5>.

  According to the polyimide resin composition according to the present disclosure, the resin composition has a specific flexural modulus, is excellent in slidability with a soft metal (for example, aluminum, copper, zinc, etc.) as a counterpart material, and is a resin composition. A resin composition excellent in its own wear resistance is provided.

  Hereinafter, an example of an embodiment of a polyimide resin composition according to the present disclosure will be described in detail. In addition, the numerical range shown using "to" in this specification shows the range which includes the numerical value described before and behind "to" as a minimum value and a maximum value, respectively.

<Polyimide resin composition>
In the polyimide resin composition according to the present disclosure, a phenol resin carbon fiber and a fluororesin are blended with a thermoplastic polyimide resin so as to have a specific composition. The polyimide resin composition according to the present disclosure has a specific bending elastic modulus and is excellent in slidability with a counterpart material by setting these components to the compositions shown below. Therefore, the polyimide resin composition according to the present disclosure has good frictional wear characteristics with soft metals (for example, aluminum, copper, zinc, etc.), and is excellent in wear resistance of the resin material itself.

(Composition ratio of polyimide resin composition)
The thermoplastic polyimide resin is contained in the range of 50 to 98 parts by mass in 100 parts by mass of the total amount of the thermoplastic polyimide resin, the phenol resin carbon fiber, and the fluororesin. When the content of the thermoplastic polyimide resin exceeds 98 parts by mass, the content of the thermoplastic polyimide resin is too large, and wear during sliding becomes significant. When the content of the thermoplastic polyimide resin is less than 50 parts by mass, the heat resistance of the resin composition tends to decrease. A preferable range of the content of the thermoplastic polyimide resin is 50 parts by mass to 92 parts by mass, and a more preferable range is 60 parts by mass to 90 parts by mass.

  The phenol resin carbon fiber is contained in the range of 1 part by mass to 40 parts by mass in 100 parts by mass of the total amount of the thermoplastic polyimide resin, the phenol resin carbon fiber, and the fluororesin. When the content of the phenol resin carbon fiber exceeds 40 parts by mass, the phenol resin carbon fiber in the polyimide resin composition easily wears the counterpart metal during sliding. Moreover, since the viscosity of a resin composition increases and it becomes easy to produce fluidity | liquidity, the shaping | molding process by injection molding etc. may become difficult. When the content of the phenol resin carbon fiber is less than 1 part by mass, it is difficult to obtain the effect of containing the phenol resin carbon fiber. The range with preferable content of a phenol resin carbon fiber is 5 mass parts-40 mass parts, More preferably, they are 5 mass parts-30 mass parts.

  The fluororesin is contained in the range of 1 to 10 parts by mass in 100 parts by mass of the total amount of the thermoplastic polyimide resin, the phenol resin carbon fiber, and the fluororesin. When the content of the fluororesin exceeds 10 parts by mass, the wear of the resin increases during sliding, and the wear resistance tends to decrease. The preferable range of the content of the fluororesin is 3 to 10 parts by mass, more preferably 5 to 10 parts by mass.

(Bending elastic modulus of polyimide resin composition)
The polyimide resin composition according to the present disclosure has a flexural modulus of 3000 MPa to 7000 MPa. The flexural modulus is preferably 3000 MPa to 6000 MPa, more preferably 3000 MPa to 5000 MPa. If the flexural modulus is less than 3000 MPa, the molded product obtained from the polyimide resin composition is excessively soft, easily deformed by stress during friction, and appropriate slidability cannot be obtained. On the other hand, if the flexural modulus is 7000 MPa, the molded product obtained from the polyimide resin composition is excessively hard and may cause wear and deformation of a soft metal that is a friction counterpart.

  Hereinafter, each component of the polyimide resin composition according to the present disclosure will be described.

(Thermoplastic polyimide resin)
In this specification, a thermoplastic polyimide resin is a resin having a polyimide bond as a repeating unit, and represents a polyimide resin having a weighted deflection temperature of 200 ° C. or higher.

  The thermoplastic polyimide resin is not particularly limited as long as the above conditions are satisfied. A preferable example of the thermoplastic polyimide resin is a polyimide resin having a repeating unit represented by the following chemical formula (1).

In the chemical formula (1), X represents a direct bond, —SO ₂ —, —CO—, —C (CH ₃ ) ₂ —, —C (CF ₃ ) ₂ —, or —S—, and R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom, an alkyl group, an alkoxy group, a halogenated alkyl group, a halogenated alkoxy group, or a halogen atom, and Y represents (A) in the following chemical formula (2), A group selected from the group consisting of (B), (C), and (D) is shown.

  The thermoplastic polyimide resin having a repeating unit represented by the chemical formula (1) is an aromatic ether diamine represented by the following chemical formula (7) and an aromatic tetracarboxylic dianhydride represented by the following chemical formula (8). The product can be produced by reacting the product with a raw material in the presence or absence of an organic solvent and imidizing the resulting polyamic acid chemically or thermally. These specific production methods can utilize the conditions of known polyimide resin production methods.

  However, in the chemical formula (7), X has the same meaning as X in the chemical formula (1).

  In the chemical formula (8), Y represents a group selected from the group consisting of (A), (B), (C), and (D) in the chemical formula (2).

In chemical formula (1) and chemical formula (7), groups represented by R ¹ , R ² , R ³ and R ⁴ are a hydrogen atom, an alkyl group, an alkoxy group, a halogenated alkyl group, a halogenated alkoxy group or a halogen atom. . Among these, a hydrogen atom is preferable.

Examples of the alkyl group represented by R ¹ , R ² , R ³ , and R ⁴ include an alkyl group having 1 to 4 carbon atoms. Specific examples include alkyl groups such as a methyl group and an ethyl group.
Examples of the alkoxy group represented by R ¹ , R ² , R ³ , and R ⁴ include an alkoxy group having 1 to 4 carbon atoms. Specific examples include alkyl groups such as methoxy group and ethoxy group.
The halogenated alkyl group represented by R ¹ , R ² , R ³ , R ⁴ is a group in which a halogen atom (a chlorine atom, a fluorine atom, a bromine atom, an iodine atom, etc.) is substituted on an alkyl group having 1 to 4 carbon atoms. Is mentioned. Specific examples include a fluoromethyl group and a trifluoromethyl group.
The halogenated alkoxy group represented by R ¹ , R ² , R ³ , or R ⁴ is a group in which a halogen atom (a chlorine atom, a fluorine atom, a bromine atom, an iodine atom, or the like) is substituted on an alkoxy group having 1 to 4 carbon atoms. Is mentioned. Specific examples include a fluoromethoxy group.
Examples of the halogen atom represented by R ¹ , R ² , R ³ , or R ⁴ include a chlorine atom, a fluorine atom, a bromine atom, and an iodine atom.

In chemical formula (1) and chemical formula (7), X represents a direct bond, —SO ₂ —, —CO—, —C (CH ₃ ) ₂ —, —C (CF ₃ ) ₂ — or —S—. Among these, X is preferably a direct bond, —SO ₂ —, —CO—, or —C (CH ₃ ) ₂ —.

  In chemical formula (1) and chemical formula (8), Y is a tetravalent aromatic group selected from the group consisting of (A), (B), (C), and (D) in chemical formula (2). Among these, Y is preferably (A) in the chemical formula (2). That is, it is preferable to use pyromellitic dianhydride as the aromatic tetracarboxylic dianhydride.

  It is more preferable that the polyimide resin composition according to the present disclosure uses a thermoplastic polyimide resin having a repeating unit represented by the following chemical formula (3) as the thermoplastic polyimide resin.

  In addition, the thermoplastic polyimide resin which has a repeating unit represented by the said Chemical formula (3) can be purchased as Mitsui Chemicals, Inc. make: brand name AURUM (trademark).

  In the polyimide resin composition according to the present disclosure, the aromatic ether diamine or aromatic tetracarboxylic dianhydride that is a raw material of the thermoplastic polyimide resin can be used alone or in combination, and the polyimide according to the present disclosure Other copolymer components may be included as long as the purpose of the resin composition is not impaired. In addition, a plurality of polyimide resins obtained from different monomers may be arbitrarily polymer blended as long as the purpose of the polyimide resin composition according to the present disclosure is not impaired.

  In the polyimide resin composition according to the present disclosure, a thermoplastic polyimide resin in which the thermoplastic composition polyimide resin has repeating units represented by the following chemical formula (4) and the following chemical formula (5) is also given as a preferred example.

However, m and n are molar ratios of the copolymer, and m / n = 4 to 99 (mol% / mol%). m / n is preferably 5 to 99, more preferably 6 to 99.
m and n each represents 1 or more.

  The thermoplastic polyimide resin having a repeating structural unit represented by the above chemical formula (4) and chemical formula (5) is prepared by using an aromatic solvent such as an aromatic ether diamine and an aromatic tetracarboxylic dianhydride as raw materials. The reaction can be performed in the presence or absence, and the resulting polyamic acid can be chemically or thermally imidized for production. These specific production methods can utilize the conditions of known polyimide resin production methods.

  In the polyimide resin composition according to the present disclosure, a thermoplastic polyimide resin in which the thermoplastic polyimide resin has a repeating unit represented by the following chemical formula (6) is also given as a preferred example.

  The thermoplastic polyimide resin having a repeating structural unit represented by the above chemical formula (6) is obtained by using the corresponding aromatic ether diamine and aromatic tetracarboxylic dianhydride as raw materials in the presence or absence of an organic solvent. The resulting polyamic acid can be produced by chemically or thermally imidizing by reacting under the following conditions. These specific manufacturing methods can utilize the conditions of the manufacturing method of a well-known thermoplastic polyimide resin.

In the polyimide resin composition according to the present disclosure, the thermoplastic polyimide resin is a melt-moldable resin. The logarithmic viscosity of the thermoplastic polyimide resin is not particularly limited, but is preferably in the range of 0.35 dl / g to 1.30 dl / g, and preferably in the range of 0.40 dl / g to 1.20 dl / g. .
When the logarithmic viscosity is 0.35 dl / g or more, a decrease in mechanical strength due to a small molecular weight of the thermoplastic polyimide resin tends to be suppressed. Further, when the logarithmic viscosity is 1.30 dl / g or less, a decrease in fluidity of the resin composition due to an excessively high molecular weight of the thermoplastic polyimide resin is suppressed. In particular, when a resin molded body is produced by a molding method such as injection molding or extrusion molding using the resin composition of the present disclosure, it can have appropriate fluidity.

  The measurement of the logarithmic viscosity of the polymer in the polyimide resin composition according to the present disclosure was performed by heating to 200 ° C. with a solvent having a concentration of 0.5 g / 100 ml in a mixed solvent of parachlorophenol / phenol (90/10 mass ratio), Measured after cooling to 35 ° C. The definition of the logarithmic viscosity is described in “Polymer Handbook” published by Asakura Shoten, edited by the Japan Society for Analytical Chemistry, 1995, first edition, P58.

(Phenolic resin carbon fiber)
In the polyimide resin composition according to the present disclosure, the phenol resin carbon fiber is a fiber obtained by a manufacturing method in which a phenol resin fiber is manufactured using a phenol resin as a raw material and then calcined and carbonized.

  As the phenol resin carbon fiber, any phenol resin may be obtained as a raw material. Examples of the phenolic resin include novolak type phenolic resins, resol type phenolic resins, and resins in which both novolac type and resol type phenolic resins are mixed.

Examples of the fiber made from a novolak type phenolic resin include fibers produced by melt spinning an uncured and thermoplastic novolak type phenolic resin and then undergoing a curing step (for example, Japanese Patent Publication No. 48-11284). See the official gazette).
Examples of the fiber using a resol type phenol resin as a raw material include a fiber obtained by adding an acid catalyst to a liquid resol type phenol resin and centrifugally spinning it (see, for example, JP-A-59-179811). ). Further, for example, fibers obtained by a so-called melt blown method in which a solid resol type phenolic resin is melted and pulled by a heated air flow from a spinning nozzle (see, for example, JP-A-9-132818) can be mentioned.
Examples of fibers made from a resin obtained by mixing both a resol type and a novolac type phenol resin are fibers obtained by a melt blown method from a mixture of both types of phenol resins (for example, JP-A-9-176918). Reference).

  Examples of the phenol resin fiber include “Kinol” (trade name, manufactured by Gunei Chemical Industry Co., Ltd.). This phenol resin fiber is a suitable fiber as a phenol resin fiber for performing firing carbonization.

Furthermore, the phenol resin fiber for performing firing carbonization is preferably adjusted by a treatment such as cutting and pulverization in order to obtain a target fiber length.
The phenol resin fiber may be cut using a known apparatus. For example, devices for cutting include devices such as a guillotine cutter, a rotary cutter, and a disk cutter.
What is necessary is just to grind | pulverize a phenol resin fiber using a well-known apparatus. For example, devices for crushing include devices such as a hammer mill, a disk mill, a vibration mill, and a ball mill.

  The phenol resin carbon fiber is obtained by firing and carbonizing a phenol resin fiber having a adjusted fiber length. The method for firing and carbonizing the phenol resin fiber is not particularly limited, but may be performed by a known method. For example, calcination carbonization may be performed using an inert gas such as nitrogen or argon, and calcination carbonization may be performed in a vacuum instead of the inert gas. The temperature of calcination carbonization is good to carry out in the range of 600 to 1200 degreeC (preferably 800 to 1000 degreeC), for example.

  The fiber length and fiber diameter of the phenol resin carbon fiber are not particularly limited. For example, the fiber length of the phenol resin carbon fiber is preferably in the range of 0.1 mm to 10 mm. When the fiber length is 0.1 mm or more, wear of the resin component is easily suppressed. On the other hand, when the fiber length is 10 mm or less, a decrease in the dispersibility of the phenol resin carbon fiber in the polyimide resin composition is easily suppressed. Moreover, as a fiber diameter of a phenol resin carbon fiber, it is good in the range of 5 micrometers-50 micrometers, for example.

(Fluorine resin)
In the polyimide resin composition according to the present disclosure, examples of the fluororesin include at least one selected from the group consisting of the following (a) to (f).
(A) In the molecule, a tetrafluoroethylene resin having a repeating structural unit represented by the chemical formula-(CF ₂ CF ₂ )-(b) In the molecule, chemical formula-(CF ₂ CF ₂ )-and chemical formula- In the molecule of tetrafluoroethylene resin-hexafluoropropylene copolymer resin (c) having a repeating structural unit represented by [CF (CF ₃ ) CF ₂ ] —, chemical formula − (CF ₂ CF ₂ ) and chemical formula − _{[CF (OC m F2 m + 1} ) CF 2 ] (wherein, m is a positive integer) tetrafluoroethylene having a repeating structural unit represented by - the perfluoroalkyl vinyl ether copolymer resin (d) in the molecule, formula - _(CF 2 CF 2) - and the formula - _(CH 2 CH ₂₎ - to repeat tetrafluoroethylene-ethylene copolymer resin having a structural unit (e) in the molecule represented by the formula - (C ₂ CH ₂₎ - and the formula - (CFClCF ₂₎ - Table with - ethylene copolymer resin (f) in the molecule, the formula _{- - (CF 2 CH 2)} 3 fluorinated ethylene chloride having a repeating structural unit represented by Vinylidene fluoride resin having a repeating structural unit

  The total content of the thermoplastic polyimide resin, the phenol resin carbon fiber, and the fluororesin is preferably 95% by mass or more, and may be 100% by mass with respect to the total amount of the resin composition.

(Other additives)
In the polyimide resin composition according to the present disclosure, if necessary, within the range that does not impair the characteristics of the polyimide resin composition according to the present disclosure (for example, 5% by mass or less (including 0% by mass)), the following Ingredients may be included.
The polyimide resin composition according to the present disclosure includes carbon fiber, glass fiber, potassium titanate fiber, aluminum borate fiber, metal fiber, ceramic fiber, boron fiber, silicon carbide fiber, asbestos fiber, rock wool fiber, and aramid fiber. You may contain at least 1 sort from the group which consists of.

  Furthermore, in the polyimide resin composition according to the present disclosure, if necessary, graphite, mica, synthetic mica, wollastonite, talc, silicone oil within a range not impairing the characteristics of the polyimide resin composition according to the present disclosure. , Fluorinated oil, glass beads, graphite, molybdenum disulfide, clay, silica, alumina, diatomaceous earth, hydrated alumina, shirasu balloon, carbon nanotube, calcium carbonate, hydrotalcite, filler, lubricant, mold release agent , Stabilizers, colorants, crystal nucleating agents and the like may be contained.

  Furthermore, the polyimide resin composition according to the present disclosure may include various liquid crystal polymers, thermoplastic resins (for example, polyetherimide, Ether nitrile, polyether ketone, polyether ether ketone, polyether ketone ketone, polyether ketone ether ketone ketone, polyamideimide, polyether sulfone, polysulfone, polyarylate and / or polyphenylene sulfide), thermosetting resin (eg epoxy A resin, a polybenzimidazole resin, a polyimide resin, or the like).

(Production method of polyimide resin composition)
The manufacturing method of the polyimide resin composition which concerns on this indication is not specifically limited, A well-known manufacturing method is applicable. For example, a mixture containing a thermoplastic polyimide resin, a phenol resin carbon fiber, and a fluororesin in a specific composition may be continuously melt-kneaded using a single-screw or multi-screw extruder, You may melt-knead by batch type, such as a lavender.
What is necessary is just to determine as temperature (cylinder temperature) in the case of melt-kneading according to melting | fusing point etc. of the resin component which comprises a polyimide resin composition.

(Molding of polyimide resin composition)
The polyimide resin composition according to the present disclosure is not particularly limited, and all known molding methods can be used. For example, a molding method may be mentioned in which molding is performed by injection molding. It can be applied to various uses by molding by injection molding. It can also be used by cutting the molded product obtained by injection molding to finish it into a final shape. In addition, it is also possible to perform molding by a conventionally known method such as extrusion molding, compression molding, and transfer molding.

For example, when molding by injection molding, conditions such as cylinder temperature, injection pressure, mold temperature, etc. may be determined according to the shape of the thermoplastic polyimide resin composition, resin molded body, and the like.
The polyimide resin composition according to the present disclosure may be molded by a molding method such as injection molding and applied as a seal ring. For example, when the polyimide resin composition according to the present disclosure is applied to a seal ring, a resin molded body obtained by injection molding or the like may be heat-treated before actual use. Effects such as an increase in crystallinity and dimensional stability can be expected by heat treatment.

(Use of polyimide resin composition)
The polyimide resin composition according to the present disclosure has a specific flexural modulus, is excellent in slidability with a soft metal (for example, aluminum, copper, zinc, etc.), and has good friction and wear characteristics of the counterpart material, Moreover, since the resin material itself is excellent in wear resistance, it can be widely used in various parts such as automobile parts and industrial machine parts that require frictional wear characteristics with soft metals.
Polyimide resin compositions include, for example, gears, thrust washers, seal rings, piston rings, turbo seal parts (abre seals), wear rings, guide rollers, retainers, bushes, transportation equipment, etc. that require sliding characteristics with soft metals. It can be applied to various sliding members.
In particular, since the polyimide resin composition has the above characteristics, it is suitable as a seal ring for a rotating shaft in a transmission such as an automobile, and can be more preferably applied as a seal ring for an automatic transmission, for example.

  Hereinafter, although the resin composition concerning this indication is explained concretely with an example, the resin composition concerning this indication is not limited to these examples. Note that “part” means “part by mass” unless otherwise specified.

  In the following examples and comparative examples, the resin compositions were evaluated in the following manner.

[Bending elastic modulus]
Based on ASTM D790, a bending test was performed at a test speed of 1.5 mm / min and a measurement temperature of 23 ° C., and a flexural modulus was measured.

[Abrasion amount (wear amount of own material, wear amount of counterpart material)]
In accordance with the Suzuki friction and wear test (JIS K7218: 1986), an aluminum alloy (ADC-12) was used as the counterpart material, and the amount of wear after 6 hours was measured in an ATF (automatic transmission fluid) at room temperature. The surface pressure was 3 MPa and the speed was 250 m / min.

[Coefficient of friction]
According to the Suzuki type friction and wear test (JIS K7218: 1986), an aluminum alloy (ADC-12) was used as a counterpart material, and the friction coefficient after 6 hours was determined in an ATF (automatic transmission fluid) at room temperature. The surface pressure and speed at this time are 3 MPa and 250 m / min.

[Limit PV value]
In accordance with Suzuki friction and wear test (JIS K7218: 1986), an aluminum alloy (ADC-12) is used as the mating material, at room temperature, at a speed of V250 m / min, in an ATF (automatic transmission fluid) and tested for 6 hours. The upper limit surface pressure P at which the composition does not buckle was determined, and the value of P × V [(MPa) × (m / min)] at that time was determined.

<Example 1>
85 parts by mass of a thermoplastic polyimide resin having a repeating structural unit represented by the chemical formula (3) (trade name: Aurum (registered trademark) PD450, manufactured by Mitsui Chemicals, Inc.) and a fluororesin (Asahi Glass Fluoropolymers, Inc.) 10 parts by mass of product name, Aflon PTFE L-180) was dry blended using a mixer. Then, using a biaxial extruder, 5 parts by mass of quinol carbon fiber (manufactured by Gunei Chemical Industry Co., Ltd., fiber length: 3 mm, fiber diameter: 11 μm to 12 μm, carbon content: 95%), which is a phenol resin carbon fiber It was supplied from a feeder, extruded at 400 ° C. to 420 ° C. and granulated to obtain pellets. The obtained pellets were supplied to an injection molding machine (cylinder temperature of 400 ° C. to 420 ° C., injection pressure of 230 MPa, mold temperature of 190 ° C.), and the test pieces defined in each test method described above were molded. Table 1 shows the results of the molded products evaluated by the test methods described above.

<Examples 2 to 4>
A test piece was molded in the same manner as in Example 1 except that the composition of the thermoplastic polyimide resin, the phenol resin carbon fiber, and the fluororesin was changed to the ratio shown in Table 1. Table 1 shows the results of each molded article evaluated by the test methods described above.

<Comparative Examples 1-3>
The test was conducted in the same manner as in Example except that the quinol carbon fiber was changed to a PAN-based carbon fiber (manufactured by Toho Tenax Co., Ltd., fiber length: 6 mm, fiber diameter: 7 μm) using acrylonitrile resin as a raw material, and the ratio shown in Table 1 was used. A piece was molded. Table 1 shows the results of each molded article evaluated by the test methods described above.

As shown in Table 1, a comparative example in which the composition of the thermoplastic polyimide resin, the phenol resin carbon fiber, and the fluororesin exceeds the specified range of the polyimide resin composition according to the present disclosure is the amount of wear of the own material and the counterpart material It can be seen that the amount of wear is inferior.
Moreover, even if the composition of the thermoplastic polyimide resin and the fluororesin is within the specified range of the polyimide resin composition according to the present disclosure, the comparative example using the PAN-based carbon fiber instead of the phenol resin carbon fiber is It can be seen that the wear amount of the own material and the wear amount of the counterpart material are inferior.

Claims (6)

50 parts by mass to 98 parts by mass of a thermoplastic polyimide resin, 1 part by mass to 40 parts by mass of a phenol resin carbon fiber, and 1 part by mass to 10 parts by mass of a fluororesin,
A polyimide resin composition having a flexural modulus of 3000 MPa to 7000 MPa. The polyimide resin composition according to claim 1, wherein the thermoplastic polyimide resin is a thermoplastic polyimide resin having a repeating structural unit represented by the following chemical formula (1).

(In the chemical formula (1), X represents a direct bond, —SO ₂ —, —CO—, —C (CH ₃ ) ₂ —, —C (CF ₃ ) ₂ —, or —S—, and R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom, an alkyl group, an alkoxy group, a halogenated alkyl group, a halogenated alkoxy group, or a halogen atom, and Y represents (A) in the following chemical formula (2) And a group selected from the group consisting of (B), (C), and (D).
The polyimide resin composition according to claim 1, wherein the thermoplastic polyimide resin is a thermoplastic polyimide resin having a repeating structural unit represented by the following chemical formula (3).
The polyimide resin composition according to claim 1, wherein the thermoplastic polyimide resin is a thermoplastic polyimide resin having a repeating structural unit represented by the following chemical formula (4) and the following chemical formula (5).


(However, m and n are the molar ratio of a copolymer, and show the range of m / n = 4-99.) The polyimide resin composition according to claim 1, wherein the thermoplastic polyimide resin is a thermoplastic polyimide resin having a repeating structural unit represented by the following chemical formula (6).
  The seal ring which shape | molded the polyimide resin composition of any one of Claims 1-5.