JP2008038062A - Sliding material composition - Google Patents

Abstract

[PROBLEMS] A conventional sliding material composition filled with glass fiber, carbon fiber, various metal powders, etc. has a high surface hardness or elastic modulus, and tends to wear a soft metal member such as aluminum or mild steel. was there.
The sliding material composition of the present invention is a composition comprising a baked carbonized phenol resin fiber and a thermoplastic resin or a thermosetting resin, and the baked carbonized phenol resin fiber has an elastic modulus. In addition, it is difficult to defibrate compared to aromatic polyamide fibers and can be uniformly dispersed in a matrix resin. Its friction coefficient and wear amount are sufficiently small and can be used practically.
[Selection figure] None

Description

  The present invention relates to a sliding material composition suitable for a case where the counterpart material is a soft metal member such as aluminum. More specifically, the present invention relates to a composition comprising a sliding resin composition comprising a calcined phenol resin fiber and a thermoplastic resin or a thermosetting resin.

  When sliding between metals such as gears and bearings, oil and grease are used together as a lubricant in order to prevent frictional resistance and wear. However, since it is necessary to periodically replenish oil and grease, a combination of a metal and a resin is becoming widespread as a method not using a lubricant in recent years. In the case of iron or stainless steel as the counterpart material, glass fiber, carbon fiber, various metal powders, and the like are filled in the resin in order to improve wear on the resin side having low surface hardness (see, for example, Patent Document 1). Furthermore, there is provided a sliding material composition filled with graphite or a fluororesin in order to lower the friction coefficient. However, with the recent trend toward weight reduction, the case of using aluminum as the counterpart material of the sliding material composition is increasing. In that case, if the sliding material composition is a member filled with conventional glass fiber, carbon fiber, various metal powders, etc., the surface hardness or elastic modulus of these fillers is high, and a soft metal member such as aluminum or mild steel Since it is easy to wear, there is a problem that it is restricted in actual use.

On the other hand, there is a description that wear resistance is improved when a very small amount of aromatic polyamide short fibers of about several percent are dispersed in a thermosetting resin (see, for example, Non-Patent Document 1). However, the combination of thermosetting resin and aromatic polyamide short fiber has poor dispersibility of the aromatic polyamide fiber in the matrix resin, making it difficult to obtain a homogeneous resin sliding material composition. Had a problem. In addition, filling an aromatic polyamide fiber into a thermoplastic resin (see, for example, Patent Document 2), the aromatic polyamide fiber is kneaded into a resin melted by an extruder or the like when the aromatic polyamide fiber is kneaded. The fiber is easily defibrated and becomes cottony, the dispersibility of the aromatic polyamide fiber in the matrix resin is poor, and it is difficult to obtain a homogeneous sliding material composition like the thermosetting resin.
Japanese Patent Laid-Open No. 11-71470 JP 2006-45413 A “Nikkei Mechanical” magazine, September 9, 1985, published by Nikkei Inc. 195-201

  The object of the present invention is to solve the above-mentioned problems of the prior art and to provide a sliding material composition having excellent sliding characteristics when the counterpart material is a soft metal member such as aluminum or mild steel. It is in.

  As a result of intensive studies on the sliding material composition, the present inventors have found that the sliding material composition is composed of a baked carbonized phenol resin fiber and a thermoplastic resin or a thermosetting resin. In the case of a metal member, it has been found that the sliding characteristics are excellent, and the present invention has been completed. That is, the calcined phenol resin fiber has a lower elastic modulus than glass fiber, carbon fiber, and various metal powders, and does not wear a soft metal member such as aluminum or mild steel as a counterpart material. Furthermore, it is difficult to defibrate compared to aromatic polyamide fiber, and it can be uniformly dispersed in a thermoplastic resin melted by an extruder or the like.

  The sliding material composition of the present invention comprises a composition of a baked carbonized phenol resin fiber and a thermoplastic resin or a thermosetting resin, and exhibits excellent sliding characteristics when the counterpart material is a soft metal member such as aluminum. Show.

  The present invention relates to a sliding material composition comprising (1) a calcined phenol resin fiber and (2) a thermoplastic resin or a thermosetting resin.

  Hereinafter, the present invention will be described in detail. The thermoplastic resin used in the present invention includes, for example, polyethersulfone, polysulfone, polyetherimide, polysulfone, polycarbonate, polyarylate, ABS, etc. as an amorphous resin, and polyphenylene sulfide, polyethylene terephthalate, poly, etc. as a crystalline resin. Examples include butylene terephthalate, aliphatic nylon, semi-aromatic nylon, aromatic nylon, polyoxymethylene, polypropylene, polyetherketone, polyetheretherketone, fluorine-based resin, and liquid crystal polymers. Examples of the thermosetting resin include epoxy resin, phenol resin, polyimide resin, silicone resin, fluorine resin, polyamideimide resin, polybenzimidazole resin, and the like.

  The calcined phenol resin fiber used in the present invention is produced by producing a phenol resin fiber and then calcining it in a high temperature furnace. Specifically, the phenol resin fiber is made of a novolac type phenol resin, a resol type phenol resin, or a mixture of both novolak type and resol type phenol resins. Any of them can be adopted. As a fiber using a novolac type phenolic resin as a raw material, for example, there is an uncured and thermoplastic novolac type phenolic resin which is melt-spun and then manufactured through a curing process (Japanese Patent Publication No. 48-11284). Examples of the fiber made from the resol type phenol resin include, for example, a fiber obtained by adding an acid catalyst to a liquid resol type phenol resin and spinning it (Japanese Patent Laid-Open No. 59-179811), or a solid resol There is a fiber (Japanese Patent Laid-Open No. 9-132818) obtained by melting a type phenolic resin and pulling and spinning by a heated air stream from a spinning nozzle. Examples of fibers made from both resol-type and novolac-type phenol resins include fibers obtained by a melt blown method from a mixture of both types of phenol resins (Japanese Patent Laid-Open No. 9-176918). Phenol resin fibers are widely used in “Kinol” (registered trademark of Nippon Kynol Co., Ltd.), and can be preferably used in the present invention.

  Furthermore, it is necessary to cut or pulverize this phenol resin fiber to adjust it to a fiber length suitable for use in the present invention. The cutting can be performed using a known apparatus such as a guillotine cutter, a rotary cutter, or a disk cutter. The pulverization can be performed using a known apparatus such as a hammer mill, a disk mill, a vibration mill, or a ball mill.

  The fiber length and fiber diameter are not particularly limited, but the fiber length is preferably in the range of 0.1 mm to 10 mm. If the fiber length is less than 0.1 mm, the reinforcing effect of the resin component which is a matrix is small, and wear tends to occur. Moreover, the thing exceeding 10 mm is not preferable because there is a risk of causing insufficient dispersion of fibers in the resin component as a matrix. The fiber diameter is not particularly limited, but the fiber diameter is preferably in the range of 5 to 50 μm.

  In order to obtain the calcined phenol resin fiber used in the present invention, it is necessary to carbonize the phenol resin fiber having the above-mentioned fiber length adjusted. Carbonization of the phenol resin fiber may be performed according to a conventionally known method. For example, nitrogen, argon etc. are mentioned as an inert gas used by carbonization. Moreover, you may carry out in a vacuum instead of an inert gas. The carbonization temperature is, for example, in the range of 600 ° C to 1200 ° C, and more preferably in the range of 800 ° C to 1000 ° C.

  The sliding material composition of the present invention preferably contains one or more lubricant imparting agents such as fluororesin, graphite, molybdenum disulfide and the like because the friction coefficient is improved. Further, in the case of a thermoplastic resin, 30 to 90% by mass of the thermoplastic resin, 5 to 40% by mass of the baked carbonized phenol resin fiber, and one of lubricant imparting agents such as fluororesin, graphite and molybdenum disulfide. Or the sliding material composition whose 2 or more types of sum total is the range of 5-30 mass% is preferable. If the thermoplastic resin is less than 30% by mass, the molding fluidity is poor and the practicality is poor. If the calcined phenol resin fiber is less than 5% by mass and the total of one or more of the lubricant imparting agents is less than 5% by mass, sufficient sliding characteristics cannot be obtained.

  In addition, fillers such as calcium carbonate, mica, glass beads, clay, silica, alumina, talc, diatomaceous earth, hydrated alumina, shirasu balloon, etc., or carbon fiber, glass fiber, titanium, etc. Potassium acid fibers, ceramic fibers, metal fibers, boron fibers, silicon carbide fibers, rock wool fibers, aramid fibers, and the like may be used in combination.

  The soft metal member such as aluminum which is the subject of the present invention includes, for example, aluminum, copper, tin, lead or zinc and an alloy containing at least one of them, but is not necessarily limited. As the sliding condition, not only unlubricated but also, for example, in grease or oil, the sliding characteristics are further improved.

  EXAMPLES The present invention will be specifically described below based on examples, but the present invention is not limited to these. The evaluation method of slidability was in accordance with the Suzuki friction and wear test.

[Test method]
(1) Friction coefficient In accordance with Suzuki's frictional wear test, Al (ADC5052) was used as the counterpart material, and the friction coefficient after 1 hour at room temperature was determined. The surface pressure and speed at this time are 10 kg / cm ² and 50 m / min.
(2) Abrasion Amount According to the Suzuki-type frictional wear test, Al (ADC5052) was used as the counterpart material, and the amount of wear for 1 hour was measured at room temperature. The surface pressure was 10 kg / cm ² and the speed was 50 m / min.

[Examples 1 and 2]
As a crystalline thermoplastic resin, polyphenylene sulfide resin (trade name T-4, manufactured by Toprene), calcined phenol resin fiber (fiber diameter 15 μ, fiber length 0.5 mm), PTFE (trade name Fullon L169J, manufactured by Asahi Glass Co., Ltd.) Were dry blended using a mixer at the ratio shown in Table 1, and then extruded and granulated at 300 ° C. using a twin-screw extruder, and the resulting pellets were injected into an injection molding machine (cylinder temperature 270 to 300 ° C., gold The mold temperature was 190 ° C.), and a test piece defined by the test method described above was molded. The results are shown in Table 1.

[Example 3]
As a crystalline thermoplastic resin, an aromatic polyamide resin (trade name: Polyamide MXD6 # 6000, manufactured by Mitsubishi Gas Chemical Co., Inc.), 70% by mass, baked carbonized phenol resin fiber (fiber diameter 15 μ, fiber length 1.0 mm) 20% by mass and 10% by mass of PTFE (trade name Fullon L169J, manufactured by Asahi Glass Co., Ltd.) was dry blended using a mixer, then extruded and granulated at 280 ° C. using a twin screw extruder, and the resulting pellets were injected into an injection molding machine ( Cylinder temperature was 240 to 280 ° C. and mold temperature was 130 ° C.), and a test piece defined in the test method described above was molded. The results are shown in Table 1.

[Example 4]
As a crystalline thermoplastic resin, polyether ether ketone resin (trade name: Victrex PEEK450P, manufactured by Victrex) 80% by mass, calcined and carbonized phenol resin fiber (fiber diameter 15 μ, fiber length 0.5 mm) 10% by mass and PTFE ( Product name Fullon L169J (manufactured by Asahi Glass Co., Ltd.) 10% by weight is dry blended using a mixer, and then extruded and granulated at 350 ° C. using a twin screw extruder, and the resulting pellets are injection molded (cylinder temperature) 300 to 360 ° C., mold temperature 200 ° C.), and a test piece defined in the test method described above was molded. The results are shown in Table 1.

[Example 5]
Polyethersulfone resin (trade name: PES grade E2010, manufactured by BASF) as an amorphous thermoplastic resin, 70% by mass, baked carbonized phenol resin fiber (fiber diameter 15 μm, fiber length 1.5 mm) 20% by mass fluororesin ( (Product name: L180, manufactured by Asahi ICI Fluoropolymers Co., Ltd.) 10% by mass dry blended using a mixer, then extruded and granulated at 330-370 ° C using a twin screw extruder, and the resulting pellets were injection molded The sample was supplied to a machine (cylinder temperature 340 to 370 ° C., mold temperature 170 ° C.), and a test piece defined in each test method described above was molded. The results are shown in Table 1.

[Example 6]
As thermosetting resin, polyamide imide resin (trade name: Torlon, manufactured by Amoco) 85% by mass, calcined phenol resin fiber (fiber diameter 15 μ, fiber length 0.5 mm) 10% by mass and PTFE (trade name: Fullon L169J, Asahi Glass) 5% by mass) was dry blended using a mixer, and then extruded and granulated at 300 to 370 ° C. using a twin screw extruder, and the resulting pellets were injection molded (cylinder temperature 320 to 370 ° C.). , A mold temperature of 200 ° C.), a test piece defined by the test method described above was molded, and the test piece was thermally crosslinked at 300 ° C. for 2 days, and then subjected to a sliding test. The results are shown in Table 1.

[Example 7]
As thermosetting resin, phenol resin (trade name: Restop PL2211, manufactured by Gunei Chemical Industry Co., Ltd.) 50 mass%, calcined phenol resin fiber (fiber diameter 15 μ, fiber length 3 mm) 30 mass%, and scaly graphite (trade name PS- 99 (made by Nishimura Graphite Co., Ltd.) 20% by mass using a mixer, and then heat-cured using a compression molding machine at a temperature of 180 ° C., a pressure of 100 kg / cm ² for 5 minutes, and determined by the test method described above. The obtained test piece was molded and subjected to a sliding test. The results are shown in Table 1.

[Example 8]
As liquid crystal polymer, 70% by mass of liquid crystalline polyester resin (trade name: Vectra, manufactured by Polyplastics Co., Ltd.), 20% by mass of calcined phenol resin fiber (fiber diameter 15 μ, fiber length 1.5 mm), fluororesin PTFE (trade name) 10% by mass of Fullon L169J (Asahi Glass Co., Ltd.) was dry blended using a mixer, then extruded and granulated at 300 ° C. using a twin screw extruder, and the resulting pellets were injected into an injection molding machine (cylinder temperature 280-800). 320 ° C. and a mold temperature of 150 ° C.), and a test piece defined in each test method described above was molded. The results are shown in Table 1.

[Comparative Example 1]
The same procedure was used except that polyparaphenylene terephthalamide fiber (trade name: Twaron chopped fiber TWND34B, manufactured by Akzo (3 mm length)) was used as an aramid fiber instead of the calcinated phenolic resin fiber in Example 1. Extrusion was performed at 300 ° C. using a twin-screw extruder and granulated. However, the aromatic polyamide fiber was disentangled in several tens of minutes, and the cotton-like one closed the resin inlet and could not be continuously produced. Part of the obtained pellets was supplied to an injection molding machine (cylinder temperature 270 to 300 ° C., mold temperature 190 ° C.), and a test piece defined in the test method described above was molded. The results are shown in Table 2, but the sliding characteristics were not satisfactory. When observed with a microscope, a mass of several hundred μ was dispersed.

[Comparative Example 2]
Example 3 was the same as Example 2 except that pitch-based carbon fiber (trade name M107, manufactured by Kureha Chemical Co., Ltd.) was used as the carbon fiber instead of the calcined phenolic resin fiber. The results are shown in Table 2, but the sliding characteristics were not satisfactory.

[Comparative Example 3]
Example 4 was the same as Example 4 except that PAN-based carbon fiber (trade name: HTA-C6, manufactured by Toho Tenax Co., Ltd.) was used as the carbon fiber instead of the calcined phenolic resin fiber. The results are shown in Table 2, but the sliding characteristics were not satisfactory.

  As is apparent from Tables 1 and 2, when a baked carbonized phenolic resin is used as the fiber, both the friction amount and the friction coefficient are small and can be sufficiently put into practical use. On the other hand, when the calcined phenolic resin is not used, both the amount of friction and the coefficient of friction are larger than those of the examples and are not practical.

Claims (3)

  A sliding material composition comprising a calcined phenolic resin fiber and a thermoplastic resin or a thermosetting resin.   The sliding material composition according to claim 1, comprising one or more of lubricant imparting agents such as fluororesin, graphite, and molybdenum disulfide.   In Claim 2, 30-90 mass% of thermoplastic resins, 5-40 mass% of baked carbonized phenol resin fibers, and one or more of lubricant imparting agents such as fluororesin, graphite, molybdenum disulfide, etc. The sliding material composition whose sum total is the range of 5-30 mass%.