JPH02185563A - Thermosetting resin composition - Google Patents

Abstract

PURPOSE:To prepare a thermosetting resin compsn. useful as a solid lubricant which neither damages a mating material nor causes an unusual wear in a long time use by compounding a thermosetting resin with para-oriented arom. polyamide particles. CONSTITUTION:100 pts.wt. thermosetting resin is compounded with 5-300 pts.wt. para-orientated arom. polyamide particles (e.g. poly-p-phenyleneterephthalaminde). The resulting thermosetting resin compsn. is useful as a solid lubricant which neither damages a mating material nor causes an unusual wear in a long time use. Thus, the production of a sliding part to be used at a high speed, e.g. a bearing, from plastics, so far considered difficult, is made possible, contributing to weight reduction and economy.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a thermosetting resin composition. More specifically, the present invention relates to a thermosetting resin composition that has excellent mechanical properties at high temperatures, is suitable for electrical parts, mechanical parts, etc., and has excellent sliding properties.

[Prior art and its problems]

In recent years, synthetic resin products have been increasingly used as machine parts in place of metal products in response to the need for lighter weight equipment and ease of manufacturing and assembly. For example, many synthetic resin products are beginning to be used in sliding members such as bearings.

In such sliding materials, polyamide, polyacetal, fluororesin, etc. have conventionally been used as resins with good sliding properties. At relatively low temperatures, low loads, and low to medium speeds, these materials satisfy the required sliding properties even without lubrication, but as they move to high temperatures, high loads, and high speeds, seizures and resin failure occur. Flow (plastic deformation)
etc., which made it unusable.

In order to improve these drawbacks, thermosetting resin is used,
Methods of adding inorganic powder, glass fiber, aromatic polyamide fiber, carbon fiber, etc. as solid lubricants have been adopted, but adding inorganic powder may damage the mating material or cause damage to the fiber-shaped material. When added, there are problems such as fibrillation, cracking, folding, etc., occurring during sliding, and a large amount of abrasion powder being deposited, resulting in a decrease in sliding properties.

On the other hand, a method of adding Mek-oriented aromatic polyamide powder as a solid lubricant to a thermosetting resin is already known. For example, JP-A-59-227924, JP-A No. 60-179418, and JP-A No. 63-6043 disclose compositions in which aromatic polyamide powder is added to a bismaleimide-based thermosetting resin together with a fluorine-based filler. Disclosed. However, in the method using meta-oriented aromatic polyamide powder, it has been found that during sliding in a high-speed region, so-called abnormal wear occurs in which the amount of wear increases rapidly at a certain period. In other words, when sliding at high speeds, meta-oriented aromatic polyamides cannot exhibit sufficient heat resistance, and as a result of their inherent lack of hardness as a solid lubricant, when used at high speeds, the It is presumed that abnormal wear occurs from this.

[Problem to be solved by the invention]

In view of these problems, an object of the present invention is to provide a solid lubricant that does not damage mating materials and does not cause abnormal wear due to long-term use.

[Means for Solving the Problems] Accordingly, the present invention provides a thermosetting resin characterized in that 5 to 300 parts by weight of para-oriented aromatic polyamide particles are blended with 100 parts by weight of a thermosetting resin. It is a curable resin composition.

The thermosetting resin used in the present invention refers to a resin that can undergo a crosslinking reaction by heating, light, radiation, etc., or a radical generator such as peroxide, etc. Specifically, it includes phenol resin, urea resin, melamine resin, etc. Resin, melamine
Phenol cocondensation resin, xylene modified phenol resin,
Examples include guanamine resin, urea-guanamine cocondensation resin, amine resin, acetoguanamine resin, unsaturated polyester resin, polyimide resin such as bismaleimide, xylene resin, epoxy resin, epoxy acrylate resin, and the like. In the present invention, not only can the exemplified resins be used alone, but also copolymers and mixtures of two or more of them can be used, and within the range of not interfering with the aspect of the present invention. For example, it can also be used as a mixture with thermoplastic resins such as polyethylene, polypropylene, polyacecool, polyamide 1, etc.

In the present invention, it is extremely important that loosely oriented aromatic polyamide particles are used. That is, in order to obtain high sliding properties in a high-speed range and stable sliding properties for a long time, the solid lubricant itself needs to have high heat resistance. Further, in order to improve the wear characteristics without damaging the mating material, appropriate hardness is required.

It is already known that aromatic polyamides generally have excellent heat resistance, and meta-oriented aromatic polyamides also have higher heat resistance than conventional general-purpose polyamides and other polymers. As expected from its molecular chain structure, polyamide has extremely high heat resistance and even better mechanical properties, and it is markedly different from meta-oriented aromatic polyamide in terms of its properties. It is a polymer with

In the present invention, it is important to use para-oriented aromatic polyamide particles having such characteristics, and the above-mentioned functions required of a solid lubricant are satisfied for the first time.

In the present invention, "para-oriented aromatic polyamide" means
Refers to a polyamide in which aromatic groups in which a divalent bond is located at the rose H position are connected by an amide bond (-C-N-), and the aromatic group specifically refers to a divalent bond. The hand is I, 4-phenylene (bara phenylene) or 4,4
'-Biphenylene, 1,4-naphthylene, etc., which are coaxially opposite to the aromatic ring, or 1,5-naphthylene, 2,6-naphthylene, which are arranged in the opposite direction parallel to the aromatic ring. means an aromatic group. These aromatic groups may contain one or more lower alkyl groups such as methyl and ethyl groups, alkoxy groups such as methoxy and ethoxy groups, and haloken groups such as chlorine.

Typical of these para -oriented aromatic fragrances Poramide include polybarabens amide, polybarafenylene telepramide, poly -4,4 'Ciamino Hens Annilid Televo Kuramide, Bo IJ -N, N' -P - Phenylene bis(p-benzamide) terephthalamide, polyvaraphenylene-26-naphthalamide, copoly-varaphenylene/3,4' (oxydiphenylene) terephthalamide, copoly-varaphenylene/4,4'(
33'-dimethylbiphenylene)-terephthalamide,
Examples include poly-2-chloro-bara phenylene terephthalamide F and the like. Among these, poly-paraphenylene terephthalamide or a copolymer in which 40 mol% or more of the repeating units constituting the polymer are paraphenylene terephthalamide units is preferred from the viewpoint of dimensional stability, heat resistance, and chemical resistance.

Such a randomly oriented aromatic polyamyl is produced by a so-called low-temperature solution polymerization method (for example, Japanese Patent Publication No. 35-1439) from a corresponding aromatic cyclic diamine and an aromatic cyclic dibasic acid halide.
9, etc.), it can be obtained in high yield as a polymer with a high degree of polymerization.

Para-oriented aromatic polyamide used in the present invention
The degree of polymerization is not particularly limited, but one having an logarithmic viscosity (ηinh) of 0.8 or more is usually used.

To obtain particles from such para-oriented aromatic polyamides,
The isolated and purified polymer is usually milled using commonly used mechanical grinding means such as ball mills, hammer mills, die mills, etc.
Obtained by grinding with a mill or the like. or,
For example, fine particles can also be obtained by the method disclosed in JP-A-62-32123. In the present invention, the means for obtaining particles is not particularly limited.

The particle size (representing the average particle size, hereinafter simply referred to as particle size) of the aromatic polyamide particles used in the present invention may vary depending on the material of the other side when used as a sliding joint, but is usually 100 μm or less. Those are preferably used.

In order to obtain particularly high sliding properties, the particle size must be increased to 5 or 50 μm.
It is preferable to use particles within this range.

The shape of the particles can be spherical, scale-like, rod-like, etc. to obtain smooth sliding properties, but in order to obtain particularly uneven sliding properties, spherical shapes are preferred. is desirable.

In the thermosetting resin composition of the present invention, the mixing ratio of the above-mentioned thermosetting resin and para-oriented aromatic polyamide particles is an important factor. It is necessary to use 5 to 300 parts by weight of aromatic polyamide particles.

If the mixing ratio of the para-oriented aromatic polyamide particles is less than 5 parts by weight, the effect is small, the friction coefficient and abrasion properties are both insufficient, and high sliding characteristics cannot be obtained. On the other hand, 3
00 parts by weight or more is not preferable because the hard para-oriented aromatic polyamide particles themselves act as a base material and increase the coefficient of friction.

The preferred mixing ratio of para-oriented aromatic polyamide particles is 5 to 5.
The amount is preferably 200 parts by weight, and more preferably 10 to 100 parts by weight from the viewpoint of heat resistance, mechanical properties, and sliding properties.

A conventionally known method may be used to mix the thermosetting resin and para-oriented aromatic polyamide particles in the above-mentioned mixing ratio to form the composition of the present invention. Specifically, for example, there is a method of mixing a thermosetting resin powder and a predetermined amount of one particle of unevenly oriented aromatic polyamide using a mixer such as a Henschel mixer, a ball mill, a tumbler mixer, or the like.

The method of molding the composition of the present invention into, for example, a sliding material is not particularly limited, but usually -■ The mixed powder is shaped by compressing it, and then heated and pressurized. A compression molding method of hardening molding is used. Further, depending on the case, it is also possible to mix a thermoplastic resin 7 and perform extrusion molding, etc., and it may be selected as appropriate depending on the usage I:I.

The thermosetting resin composition of the present invention contains, in addition to the thermosetting resin and the para-oriented aromatic polyamide particles, additives and fillers that can be widely incorporated into synthetic resins. They can be used in combination as appropriate within a range that does not reduce the properties. Such additives include, for example, a mold release agent, f
Examples include, but are not limited to, refractory agents, weather resistance improvers, etc., and it is of course possible to use conventionally known and publicly used solid or liquid lubricants, such as tetrafluoroethylene resin, Graphi 1~, fluorinated graphite, talc, boron nitride, silicone resin or oil, and other industrial lubricants can also be selected and used as appropriate depending on the purpose of use. In any case, it is of course possible to modify the intermediate or final product to improve its properties by chemical or physical treatment, as long as the performance of the thermosetting resin composition of the present invention is not impaired.

EXAMPLES Hereinafter, the present invention will be explained in more detail and concretely using examples.

Evaluation of friction and wear properties Friction coefficient: surface pressure of 10 kg/
c+fl, linear velocity 60 cm/sec, 50 hours, mating material 34
Measured without 5C oil.

Wear coefficient: surface pressure 2kg/c by precious wood type friction and wear tester
Ifl, linear velocity 60 cm/sec, 50 hours, mating material 345
C Measured without oil.

Reference Example 1 8.5 kg of lithium chloride and 10.8 kg of paraphenylenediamine were added and dissolved in 250 kg of N-methyl-2-pyrrolidone in a polymerization vessel equipped with a stirrer, and then 20.5 kg of powdered terephthalic acid chloride was added. Polymerization was carried out by adding 3 kg at once. About 3 minutes after the addition, stirring became difficult, so stirring was stopped and the mixture was allowed to stand for 30 minutes, to obtain a polymerized and solidified dope that solidified into a cheese shape.

Next, this polymerized and solidified dope was put into a Henschel mixer together with water and stirred for 30 minutes to perform pulverization. This Henschel mixer is equipped with a vertical blade located at a distance of 5 mm from the vessel wall. After finishing the crushing operation,
The contents were taken out and the polymer particles were washed with water and then dried.

The obtained dry particles were placed in a Wiley-type pulverizer and pulverized to obtain particles of polyparaphenylene terephthalamyl having average particle diameters of 37 μm and 84 μm, respectively.

Logarithmic viscosity of the obtained particles (ηinh = ff1n77
r/C.

Measured in 98% sulfuric acid at 30°C 0.2g/100cc)
was 4.78.

Reference Example 2 Polymetaphenylene isophthalamide particles (average particle diameter: 78 μm) were obtained from metaphenylene diamine and isophthalic acid chloride in the same manner as in Reference Example 1.

Examples 1-4. Comparative Examples 1 and 2 The poly-
It was mixed with paraphenylene terephthalamide powder at the mixing ratio shown in Table 1, and then a test piece was molded at a mold temperature of 180° C. and a curing time of 45 seconds.

Using this test piece, a friction and wear test was conducted and the results obtained are shown in Table 1.

For comparison, a molded test piece containing no poly-paraphenylene terephthalamide powder was prepared in the same manner and evaluated. The results are listed in Table 1, and it was proven that the molded product of the present invention was superior to these comparative examples in terms of both friction and abrasion properties.

Example 5 As a thermosetting resin, 125 gr of Kerimid '1000 powder manufactured by Rhone Poulenc and 37.5 gr of the poly-bula phenylene terephthalamide powder having an average particle diameter of 84 μm obtained in Reference Example 1 were mixed. The obtained mixed powder is filled into a mold and 300 kg/c+f
l.

It was heated and cured at 230°C for 15 minutes to form a test piece for evaluation of friction and abrasion properties. The friction coefficient of this test piece is 0.17, and the wear coefficient is 0.1XIO-1.
°cnl/kg -c+n, and had extremely excellent friction and wear characteristics.

〔Effect of the invention〕

As is clear from the above explanation and examples (by blending para-oriented aromatic polyamide particles into a thermosetting resin, the sliding properties, especially in the high-speed range, are significantly improved, and the sliding properties are stable for a long time. As a result, it becomes possible to use resin for sliding materials such as bearings in high-speed ranges, which has been considered difficult in the past, and has great effects in terms of weight reduction and economic efficiency.

Patent applicant: Asahi Kasei Industries, Ltd.

Claims (1)

[Claims] (1) A thermosetting resin composition comprising 5 to 300 parts by weight of para-oriented aromatic polyamide particles per 100 parts by weight of the thermosetting resin.