JP2015048461A - Resin composition for sliding member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition having excellent toughness and heat resistance and having reduced rolling fatigue wear at ordinary temperature and in a high temperature environment, and a molded body thereof.SOLUTION: There is provided a resin composition comprising, to 100 pts.mass of a resin component made of (A) a polyamide 9T resin in which intrinsic viscosity is 1.0 dl/g or higher in 20 to 80 pts.mass and (B) a polyamide 66 resin in 80 to 20 pts.mass, (C) a polyarylene sulfide resin in 0 to 45 pts.mass and (D) a carbon fiber in which a fiber convergence agent being polyamide series in 5 to 85 pts.mass.

Description

  The present invention relates to a resin composition used for a sliding member that causes rolling sliding such as a ball bearing, a roller bearing, a linear bearing, and the like, and a molded body thereof.

Rolling bearing wear (flaking) due to rolling sliding is one of the major factors in the life of rolling bearings. Therefore, the sliding member of the rolling bearing is required to be resistant to rolling fatigue wear. Other requirements for the sliding member include that the bearing can withstand large deformation during assembly of the bearing and that it does not break, that is, has excellent toughness. In addition, the usage environment and conditions of final products incorporating rolling bearings are becoming stricter year by year, and heat resistance, light weight, productivity (time and cost), etc. are also required.
Among these various requirements, conventionally used metals and thermosetting resins are sufficient for heat resistance requirements. However, it is difficult for these materials to satisfy light weight, productivity, and rolling fatigue wear resistance at the same time. In particular, in terms of productivity, when the shape of the sliding member is complicated, secondary processing such as cutting is often required, which takes time and cost. Therefore, it can be said that light weight and productivity can be satisfied at the same time by producing by injection molding using a thermoplastic resin excellent in rolling fatigue wear resistance, toughness, and heat resistance.

A typical example of a resin excellent in rolling fatigue resistance is polyamide 66 resin, and a fiber-reinforced compound product is used in an actual product. However, when it is operated continuously for a long time in a high temperature environment exceeding 150 ° C., the wear is remarkably large and the application is difficult.
On the other hand, as a sliding member that can withstand long-term use under a high temperature and high surface pressure environment, a semi-fragrance comprising a terephthalic acid unit and a 1,9-nonanediamine unit and / or a 2-methyl-1,8-octanediamine unit. A rolling sliding member using a group 9 polyamide resin and containing a filler is known (Patent Document 1).
Therefore, as a resin composition having little rolling fatigue wear under normal temperature and high temperature environments, a resin composition in which a semi-aromatic polyamide 9T resin having high heat resistance is blended with a polyamide 66 resin resistant to rolling fatigue wear can be considered.

  However, according to the study by the present inventors, if the polyamide 9T resin is simply blended with the polyamide 66 resin and reinforced with, for example, glass fiber, the molded product of the composition has toughness, heat resistance and mechanical properties. However, it was difficult to say that the rolling fatigue wear resistance at room temperature and high temperature was excellent.

Japanese Patent No. 4766649

  An object of the present invention is to obtain a resin composition having excellent toughness and heat resistance, and excellent in rolling fatigue wear resistance in a normal temperature and high temperature environment, and a molded product thereof.

  As a result of various studies, the present inventors have included a specific amount of carbon fiber whose fiber sizing agent is polyamide based in a polyamide resin composition having a specific mass ratio of a polyamide 9T resin and a polyamide 66 resin having a specific intrinsic viscosity. The present inventors have found that a resin composition that solves the above problems and a molded product thereof can be obtained by containing a specific amount of polyarylene sulfide resin as required.

That is, the present invention is as follows.
[1] For 100 parts by mass of a resin component composed of 20 to 80 parts by mass of polyamide 9T resin having an intrinsic viscosity of 1.0 dl / g or more and (B) 80 to 20 parts by mass of polyamide 66 resin, C) Polyarylene sulfide resin 0 to 45 parts by mass, and (D) a resin composition containing 5 to 85 parts by mass of carbon fiber whose fiber sizing agent is a polyamide.
[2] The resin composition according to the above [1], wherein the polyarylene sulfide resin is a polyphenylene sulfide resin.
[3] The resin composition according to the above [1] or [2], wherein the bending strain in the ASTM tensile test piece is 3% or more.
[4] A molded article comprising the resin composition according to any one of [1] to [3].
[5] The molded article according to [4], which is used for rolling and sliding use.

  The resin composition of the present invention has excellent toughness and heat resistance, and is excellent in rolling fatigue wear resistance under normal temperature and high temperature environments. Therefore, the molded body made of the resin composition of the present invention can be suitably used for various sliding members, in particular, bearings, general linear guides, particularly linear bush cages.

FIG. 1 is a cross-sectional view schematically showing an outline of a “rolling fatigue wear tester” used in an embodiment of the present invention.

  The resin composition of the present invention comprises (A) 20 to 80 parts by mass of a polyamide 9T resin having an intrinsic viscosity of 1.0 dl / g or more and (B) 100 parts by mass of a resin component comprising 80 to 20 parts by mass of a polyamide 66 resin. In contrast, (C) 0 to 45 parts by mass of polyarylene sulfide resin and (D) 5 to 85 parts by mass of carbon fiber in which the fiber sizing agent is a polyamide system.

(A) Polyamide 9T Resin The (A) polyamide 9T resin used in the present invention imparts excellent rolling fatigue resistance to the resin composition of the present invention, particularly excellent rolling fatigue resistance in a high temperature environment. .
Here, the (A) polyamide 9T resin used in the present invention requires that the intrinsic viscosity [η] measured in concentrated sulfuric acid at 30 ° C. is 1.0 dl / g or more, and 1.1 dl / g or more. Preferably there is. When the intrinsic viscosity [η] is less than 1.0 dl / g, rolling fatigue wear at room temperature and high temperature is remarkably increased.

  The polyamide 9T resin has a dicarboxylic acid component in which 60 to 100 mol% of all dicarboxylic acid components are terephthalic acid and 60 to 100 mol% of all diamine components are 1,9-nonanediamine and / or 2-methyl-1,8- It is a semi-aromatic polyamide resin comprising a diamine component which is octanediamine. Specifically, it is a semi-aromatic polyamide resin mainly composed of polynonamethylene terephthalamide and / or poly 2-methyloctamethylene terephthalamide.

  The dicarboxylic acid component of the polyamide 9T resin contains terephthalic acid in an amount of 60 to 100 mol% of the total dicarboxylic acid component. The content of terephthalic acid in the dicarboxylic acid component is preferably 75 to 100 mol%, more preferably 90 to 100 mol%.

  Examples of dicarboxylic acid components other than terephthalic acid include malonic acid, dimethylmalonic acid, succinic acid, glutaric acid, adipic acid, 2-methyladipic acid, trimethyladipic acid, pimelic acid, 2,2-dimethylglutaric acid, 3, 3 Aliphatic dicarboxylic acids such as diethyl succinic acid, azelaic acid, sebacic acid and suberic acid; alicyclic dicarboxylic acids such as 1,3-cyclopentanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid; isophthalic acid, 2,6 -Naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,4-phenylenedioxydiacetic acid, 1,3-phenylenedioxydiacetic acid, diphenic acid, dibenzoic acid, 4, 4′-oxydibenzoic acid, diphenylmethane-4,4′-dicarboxylic acid, diphenylsulfone-4, '- dicarboxylic acid, there may be mentioned units derived from aromatic dicarboxylic acids such as 4,4'-biphenyl dicarboxylic acid, may be used alone or two or more of them.

The diamine component of the polyamide 9T resin contains 1,9-nonanediamine and / or 2-methyl-1,8-octanediamine in an amount of 60 to 100 mol% of the total diamine component. The total content of 1,9-nonanediamine and 2-methyl-1,8-octanediamine in the diamine component is preferably 70 to 100 mol%, more preferably 80 to 100 mol%.
When 1,9-nonanediamine and 2-methyl-1,8-octanediamine are used in combination, the molar ratio of 1,9-nonanediamine: 2-methyl-1,8-octanediamine is preferably 30: 70-95: 5, More preferably, it is 40: 60-90: 10, More preferably, it is 60: 40-90: 10.

  Examples of diamine components other than the above include ethylenediamine, propylenediamine, 1,4-butanediamine, 1,6-hexanediamine, 1,8-octanediamine, 1,10-decanediamine, 1,12-dodecanediamine, 2- Methyl-1,5-pentanediamine, 3-methyl-1,5-pentanediamine, 2,2,4-trimethyl-1,6-hexanediamine, 2,4,4-trimethyl-1,6-hexanediamine, Aliphatic diamines such as 5-methyl-1,9-nonanediamine; cycloaliphatic diamines such as cyclohexanediamine, methylcyclohexanediamine, and isophoronediamine; p-phenylenediamine, m-phenylenediamine, p-xylylenediamine, m-xylylene Range amine, 4,4'-diaminodiphenylmethane, 4,4'-di Mino diphenyl sulfone, aromatic diamines such as 4,4'-diaminodiphenyl ether, or can be given any mixture thereof.

  In addition, the end of the molecular chain of the polyamide 9T resin is preferably sealed with an end-capping agent, and the end group is preferably 40 mol% or more, more preferably 60 mol% or more, and even more preferably 70 mol. % Or more is preferably sealed.

  The end capping agent is not particularly limited as long as it is a monofunctional compound having reactivity with the amino group or carboxyl group at the end of the polyamide. From the viewpoint of reactivity and stability of the capping end, monocarboxylic acid is used. An acid or a monoamine is preferable, and a monocarboxylic acid is more preferable from the viewpoint of easy handling. In addition, acid anhydrides such as phthalic anhydride, monoisocyanates, monoacid halides, monoesters, monoalcohols, and the like can be used.

  The monocarboxylic acid used as the terminal blocking agent is not particularly limited as long as it has reactivity with an amino group. For example, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, Aliphatic monocarboxylic acids such as lauric acid, tridecylic acid, myristic acid, palmitic acid, stearic acid, pivalic acid, and isobutyric acid; alicyclic monocarboxylic acids such as cyclohexanecarboxylic acid; benzoic acid, toluic acid, α-naphthalenecarboxylic acid Examples thereof include aromatic monocarboxylic acids such as acid, β-naphthalenecarboxylic acid, methylnaphthalenecarboxylic acid, and phenylacetic acid, or any mixture thereof. Of these, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, lauric acid, tridecylic acid, myristic acid, palmitic acid, stearic acid, in terms of reactivity, stability of the sealing end, price, etc. Benzoic acid is particularly preferred.

  The monoamine used as a terminal blocking agent is not particularly limited as long as it has reactivity with a carboxyl group. For example, methylamine, ethylamine, propylamine, butylamine, hexylamine, octylamine, decylamine, Aliphatic monoamines such as stearylamine, dimethylamine, diethylamine, dipropylamine, dibutylamine; alicyclic monoamines such as cyclohexylamine, dicyclohexylamine; aromatic monoamines such as aniline, toluidine, diphenylamine, naphthylamine, or any of these Mention may be made of mixtures. Of these, butylamine, hexylamine, octylamine, decylamine, stearylamine, cyclohexylamine, and aniline are particularly preferable from the viewpoints of reactivity, boiling point, stability of the sealing end, and price.

  The amount of the end-capping agent used when producing the polyamide 9T resin is determined from the intrinsic viscosity [η] of the finally obtained polyamide resin and the end group sealing rate. The specific amount used varies depending on the reactivity, boiling point, reaction apparatus, reaction conditions, etc. of the end-capping agent used, but is usually within a range of 0.5 to 10 mol% with respect to the total number of moles of diamine. used.

(B) Polyamide 66 resin The polyamide 66 resin used in the present invention is an aliphatic polyamide resin composed of adipic acid and 1,6-hexamethylenediamine, and imparts rolling fatigue resistance to the resin composition of the present invention. .
The polyamide 66 resin can be produced by a known method, and the viscosity number at a formic acid concentration of 90% is preferably 130 to 150 [ml / g], and preferably 135 to 145 [ml / g]. More preferred.

(C) Polyarylene sulfide resin (C) Polyarylene sulfide resin used as necessary in the present invention is a polymer having a repeating unit represented by the following general formula (I), and the resin composition of the present invention has a high temperature. The stability of rolling sliding can be improved.
-(Ar-S)-(I)
(In the formula (I), Ar represents an arylene group, and S represents sulfur.)

  Among the polyarylene sulfide resins, it is preferable to use a polyphenylene sulfide resin in which the arylene group is a phenylene group. Examples of such polyphenylene sulfide resin include polyphenylene sulfide resins in which the arylene group is represented by the following structural formula.

The polyphenylene sulfide resin comprising these phenylene groups may be either a homopolymer comprising the same repeating unit, a copolymer comprising two or more different phenylene groups, or a mixture thereof.
Further, in the polyarylene sulfide resin, a part of the polymer chain may be substituted with another polymer as long as the effects of the present invention are not impaired. Examples of the polymer to be substituted in this way include polyamide polymers, polyester polymers, polyarylene ether polymers, polystyrene polymers, polyolefin polymers, fluorine-containing polymers, polyolefin elastomers, polyamide elastomers, and silicone elastomers. Can be mentioned.
Such polyarylene sulfide resin can be produced, for example, by the method described in Japanese Patent Publication Nos. 45-3368 and 52-12240. The polyarylene sulfide resin may be heated to increase the molecular weight in the air, or may be chemically modified using a compound such as an acid anhydride.

  The melt viscosity (shear rate 1216 / sec) at 300 ° C. of the polyarylene sulfide resin used as necessary in the present invention is preferably 100 to 1500 poise, and more preferably 350 to 700 poise.

(D) Carbon fiber (D) Carbon fiber used for this invention improves the mechanical characteristic of the resin composition of this invention, and there exists an effect | action which improves bending strength especially.
In the present invention, a polyamide-based fiber sizing agent is used from the viewpoint of compatibility with the matrix resin. When other fiber sizing agents are used, rolling fatigue wear at room temperature and high temperature is remarkably increased. The carbon fiber is preferably chopped fiber having a cut length of 6 mm and a fiber diameter of 6 to 7 μm.
When replaced with glass fiber with the same volume fraction as carbon fiber, rolling fatigue wear at room temperature and high temperature is significantly increased and cannot be used.

  In addition to the above components (A) to (D), the heat resistant resin composition of the present invention includes an antioxidant, a nucleating agent, a plasticizer, a mold release agent, a flame retardant, a pigment, carbon black, and an antistatic agent. Arbitrary arbitrary additives, such as these, can be mix | blended in the range which does not inhibit the effect of this invention.

  For example, if it is about 1 mass% of the whole, an antioxidant may be added for the purpose of improving the thermal stability of the compound and the product. As the antioxidant, pentaerythritol tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) brovionate] (manufactured by Ciba Japan, IRGANOX 1010) is preferable.

In the resin composition of the present invention, when the total of (A) the polyamide 9T resin having an intrinsic viscosity of 1.0 dl / g or more and (B) the polyamide 66 resin is 100 parts by mass, (A) the intrinsic viscosity is 1 The content ratio (parts by mass) of polyamide 9T resin: (B) polyamide 66 resin which is 0.0 dl / g or more is 20:80 to 80:20, preferably 40:60 to 80:20, more preferably 60. : 40 to 80:20.
When the polyamide 9T resin having an intrinsic viscosity of 1.0 dl / g or less is less than 20 parts by mass, the heat resistance is poor, and rolling fatigue wear at high temperatures is remarkably increased. Remarkably larger.

In the heat-resistant resin composition of the present invention, (C) with respect to 100 parts by mass of a polyamide resin component comprising (A) a polyamide 9T resin having an intrinsic viscosity of 1.0 dl / g or more and (B) a polyamide 66 resin. Content of polyarylene sulfide resin is 0-45 mass parts, Preferably it is 1-30 mass parts, More preferably, it is 1-10 mass parts.
When the polyarylene sulfide is 45 parts by weight or more, the toughness is poor, and rolling fatigue wear at room temperature and high temperature is remarkably increased. Moreover, the stability of rolling sliding at high temperature is improved by including 1 part by weight or more of polyarylene sulfide.

Further, in the heat resistant resin composition of the present invention, (A) with respect to 100 parts by mass of a polyamide resin component consisting of a polyamide 9T resin having an intrinsic viscosity of 1.0 dl / g or more and (B) a polyamide 66 resin, D) Content of the carbon fiber whose fiber sizing agent is polyamide is 5 to 85 parts by mass, preferably 10 to 50 parts by mass, and more preferably 10 to 15 parts by mass.
If the carbon fiber is less than 5 parts by mass, the bending strength (strength) is poor, and rolling fatigue wear at room temperature and high temperature is remarkably increased. If the carbon fiber is 85 parts by mass or more, the toughness is poor, and rolling fatigue wear at room temperature and high temperature is remarkably increased.

There is no restriction | limiting in particular about the preparation method of the resin composition of this invention, It can prepare by a well-known method. For example, the above components may be mixed at various temperatures and then blended by various methods such as melt kneading, and the method is not particularly limited.
Among the mixing / kneading methods, melt kneading using a twin screw extruder is preferably used. In melt kneading using a twin screw extruder, kneading at 310 ° C. or more and less than 340 ° C. is preferable. By setting the kneading temperature to 310 ° C. or higher, the polyamide 9T resin having the highest melting point as a raw material does not completely melt and the viscosity does not become too high, so that the productivity is not lowered. Further, by setting the temperature to less than 340 ° C., it is possible to minimize the thermal decomposition of the polyamide 66 resin having the lowest decomposition temperature as a raw material.

There is no restriction | limiting in particular also about the shaping | molding method using the resin composition of this invention, It is possible to use well-known shaping | molding processing methods, such as injection molding and extrusion molding. Of these, injection molding is preferably used.
The molding temperature during injection molding is preferably 300 ° C or higher and lower than 340 ° C. By setting the molding temperature to 300 ° C. or higher, the fluidity does not decrease because the melting temperature is higher than the melting point of the melt-kneaded resin mixture. Moreover, by making it less than 340 degreeC, it does not exceed the decomposition temperature of the resin mixture melt-kneaded, and thermal decomposition can be suppressed to the minimum.
Moreover, as mold temperature, 120-160 degreeC is preferable and 130-140 degreeC is further more preferable. By setting the mold temperature to 130 ° C. or higher, the mixture is sufficiently crystallized, and the performance of the present composition is sufficiently exhibited. Moreover, by setting it as 140 degrees C or less, the deformation | transformation of the resin at the time of mold release can be suppressed.

Hereinafter, the present invention will be described more specifically based on examples, but the present invention is not limited to these examples.
In addition, the physical property test and the rolling fatigue wear test in the following examples and comparative examples were performed as follows.

(1) Bending strength (strength)
Measured according to ASTM D790. Tests were carried out after leaving a test piece molded to a thickness of 3.2 mm according to ASTM D790 dimensions at a temperature of 23 ± 5 ° C. and a humidity of 50 ± 10% for 48 hours. The R diameter of the fulcrum was 2 mm at the bottom, 5 mm at the top, the span was 50 mm, and the test speed was 2 mm / min.
If it is 200 MPa or more, it can be said that the product has sufficient strength for practical use. In the case of less than 200 MPa, “x” is added in Table 1.

(2) Bending strain (toughness)
Measured according to ASTM D790. Tests were carried out after leaving a test piece molded to a thickness of 3.2 mm according to ASTM D790 dimensions at a temperature of 23 ± 5 ° C. and a humidity of 50 ± 10% for 48 hours. The R diameter of the fulcrum was 2 mm at the bottom, 5 mm at the top, the span was 50 mm, and the test speed was 2 mm / min.
If it is 3% or more, it can be said that the product has sufficient toughness for practical use. In the case of less than 3%, “x” is added in Table 1.

(3) Deflection temperature under load (heat resistance)
Measured according to ASTM D648. Tests were carried out after leaving a test piece molded to a thickness of 3.2 mm according to ASTM D648 standard at a temperature of 23 ± 5 ° C. and a humidity of 50 ± 10% for 48 hours. The load was 1.8 MPa, the heating rate was 120 ° C./h, the strain was 0.26 mm, and the span was 100 mm.
If it is 220 degreeC or more, it can be said that it has sufficient heat resistance practically as a product. In the case of less than 220 ° C., “x” is added in Table 1.

(4) Rolling fatigue wear (rolling fatigue wear resistance) in high-temperature and normal-temperature atmospheres
This test is a sliding test in which the rolling element 3 (ball) of a single type thrust ball bearing is rotated (autorotated, revolved) while being pressed against the surface of the resin molded body 1 with a constant load to generate fatigue wear on the resin molded body 1. .
The configuration of the testing machine includes a non-rotating side and a rotating side. On the non-rotating side, the disk-shaped resin molded body 1 is fixed to the metal holder 7, and this is attached to the non-rotating shaft 6 with high accuracy. On the rotation side, the race ring 2 with a race is fixed to the rotation shaft 5 with high accuracy, and the rolling element 3 and the retainer 4 for holding it are placed on the race ring 2. The upper end of the non-rotating shaft 6 is connected to the load cell via a spring coil (not shown).
When the load cell itself moves downward by the screw mechanism of the tester main body, the spring coil is compressed, a load corresponding to the compression displacement amount and the spring constant is generated, and the rolling element 3 is pressed against the surface of the resin molded body 1. The pressing load is detected by the load cell, and is controlled to be constant by feedback so as to become a set load. When the rotating shaft 5 is rotated at a constant peripheral speed in this state, the rolling element 3 and the cage 4 rotate (revolve) in conjunction with each other, and the rolling element 3 rolls and slides on the surface of the resin molded body 1 (autorotation). To do. The frictional heat transmitted to the holder 7 at that time is measured by the thermocouple 8. Further, the torque (rolling resistance) transmitted from the rotating shaft 5 to the non-rotating shaft 6 can be detected (not shown). When wear of the resin molded body 1 proceeds due to rolling fatigue, the non-rotating side is displaced downward by the amount of wear. The amount of displacement is read by a sensor, and when the displacement due to wear exceeds a certain level (15 μm or more in this study), the test is stopped, and the rolling fatigue wear resistance of the resin material is relative to the length of the previous time (lifetime). Comparison or pass / fail judgment is made.
In addition, by attaching and detaching the furnace 9, the test can be performed in a normal temperature atmosphere and a high temperature atmosphere.

The test conditions are as follows.
The thrust load in the thrust direction was 50 N, the rotation speed of the rotating shaft 6 was 2970 rpm (3.5 m / s), the test temperature in a high temperature atmosphere was 150 ° C., and the test temperature in a normal temperature atmosphere was 23 ° C., which is room temperature. The rolling element 3, the cage 4, and the raceway ring 2 with a race were used from a single type thrust ball bearing (model number: 51104) manufactured by NSK. The material of the rolling element 3 which is the counterpart material of the resin molded body is SUJ2.
A disk-shaped molded product having a thickness of 3.0 mm and φ50.0 mm was used as a test piece, and the test piece was immersed in pure water at 23 ° C. for 72 hours, and then the test was performed in a normal temperature atmosphere or a high temperature atmosphere.
When the displacement due to wear does not reach 15 μm even after 200 hours, it is assumed that the wear resistance is practically sufficient, and is indicated by “◯” in Table 1, and otherwise indicated by “X”.

  In the above test, when the change in wear displacement during the test is small and the rolling slide is stable (the amplitude of the wear displacement waveform is about 0 to 4 μm), the stability of the rolling slide is shown in Table 1 as “◯”, somewhat unsatisfactory. When stable behavior is observed (wear displacement waveform amplitude is about 5-9 μm), rolling sliding stability is “△”, and when change is large and unstable (wear displacement waveform amplitude is 10 μm or more), rolling The stability of sliding was expressed as “×”.

  In addition, this test was originally devised in the position of the acceleration test, and the set value of 200 hours is different from the lifetime when applied to a practical product.

Examples 1-7 and Comparative Examples 1-8
After dry blending the following blending components in the proportions shown in Table 1, melt-kneading is performed using a twin screw extruder at a cylinder temperature of 320 ° C. while side-feeding reinforcing fibers (carbon fibers or glass fibers). After cooling the strands in a water bath, the pellets were prepared by cutting to a certain width with a pelletizer.
The obtained pellet was processed into a test piece shape according to the above-mentioned various tests (1) to (4) by injection molding, and the test was carried out. The test results are shown in Table 1.

<Polyamide 9T resin-1 (PA9T-1 (intrinsic viscosity 1.2 dl / g))>
Semi-aromatic polyamide resin (grade name, manufactured by Kuraray Co., Ltd.) obtained from a dicarboxylic acid component mainly composed of terephthalic acid and a diamine component mainly composed of 1,9-nonanediamine and 2-methyl-1,8-octanediamine “GC72010”).

<Polyamide 9T resin-2 (PA9T-2 (intrinsic viscosity 0.9 dl / g))>
Semi-aromatic polyamide resin (grade name, manufactured by Kuraray Co., Ltd.) obtained from a dicarboxylic acid component mainly composed of terephthalic acid and a diamine component mainly composed of 1,9-nonanediamine and 2-methyl-1,8-octanediamine “GC61210”).

<Polyamide 66 resin (PA66)>
Aliphatic polyamide resin (made by Rhodia Japan, grade name “27AE1K”) composed of adipic acid and 1,6-hexamethylenediamine.

<Polyphenylene sulfide resin (PPS)>
Resin composed of repeating units of phenylene and sulfur (made by DIC, grade name “LR-2G”).

<Carbon fiber-1 (CF-1 (nylon-based sizing agent))>
PAN chopped carbon fiber having a diameter of 6 to 7 μm. Nylon fiber sizing agent is used (manufactured by Mitsubishi Rayon Co., Ltd., grade name “TR06NLB6R”).

<Carbon fiber-1 (CF-2 (urethane sizing agent))>
PAN chopped carbon fiber having a diameter of 6 to 7 μm. Urethane fiber sizing agent is used (Mitsubishi Rayon Co., grade name “TR06ULB6R”).

<Glass fiber (GF)>
Glass fiber with a diameter of 10 μm (Owens Corning, grade name “CS03 JAFT591”)

The following is confirmed from the results of the above examples and comparative examples.
For example, when polyamide 9T resin-2 having a low intrinsic viscosity is used, rolling fatigue wear at room temperature and high temperature is large (Comparative Example 6), and glass fiber is used as a filler at room temperature and high temperature. Rolling fatigue wear resistance and rolling sliding stability are poor (Comparative Example 7), and using a urethane-based sizing agent carbon fiber has poor rolling fatigue wear resistance at room temperature and high temperature ( Comparative Example 8).
On the other hand, by blending the polyamide 9T resin-1, polyamide 66 resin, polyphenylene sulfide resin, and carbon fiber whose fiber sizing agent is polyamide-based within the scope of claim 1, it has excellent toughness and heat resistance, Resin compositions with less rolling fatigue wear under normal temperature and high temperature environments are obtained (Examples 1 to 7).

  The resin composition of the present invention is excellent in rolling fatigue wear resistance and toughness for sliding members, and particularly has excellent sliding characteristics at high temperatures, and is used for bearings, general linear guides, especially linear bush cages, etc. It can be used suitably.

DESCRIPTION OF SYMBOLS 1 Resin molding 2 Raceway 3 Rolling body 4 Cage 5 Rotating shaft 6 Non-rotating shaft 7 Metal holder 8 Thermocouple 9 Furnace

Claims (5)

  (A) Polyamide 9T resin having an intrinsic viscosity of 1.0 dl / g or more 20 to 80 parts by mass and (B) Polyamide 66 resin 80 to 20 parts by mass with respect to 100 parts by mass of resin component (C) Poly A resin composition comprising 0 to 45 parts by mass of an arylene sulfide resin and 5 to 85 parts by mass of (D) a carbon fiber in which the fiber sizing agent is polyamide.   The resin composition according to claim 1, wherein the polyarylene sulfide resin is a polyphenylene sulfide resin.   The resin composition according to claim 1 or 2, wherein the bending strain in the ASTM tensile test piece is 3% or more.   The molded object which consists of a resin composition in any one of Claims 1-3.   The molded article according to claim 4, which is used for rolling and sliding applications.

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