JPS636043A - Heat-resistant resin composition for molding - Google Patents

Abstract

PURPOSE:To provide the title compsn. having excellent heat resistance, mechanical characteristics at high temp. and sliding properties against soft metal, consisting of a specified thermosetting resin and a composite filler contg. a fluororesin and an arom. polyamide powder. CONSTITUTION:100pts.wt. polymaleimide of formula I (wherein R<1> is an N-valent org. group; X<1> and X<2> are each a monovalent member selected from the group consisting of H, halogen and org. groups; and n is a number of not smaller than 2) is reacted with 5-40pts.wt. aminophenol of formula II (wherein R<2> is X<1>; and m is a number of 1-5) at 50-200 deg.C for several min to several tens of hr. The resulting addition reaction product, an epoxy compd. having at least two epoxy groups per molecule (e.g., a bisphenol A type epoxy resin) and a poly-p-vinylphenol are subjected to a dehydrogenation and thermal polymn. reaction to obtain a thermosetting resin (A) having an MW of 2,500-8,000 and a hydroxyl value of 120. 30-70wt% component A is blended with 70-30wt% composite filler (B) contg. 50-83wt% fluororesin and 5-38wt% arom. polyamide powder having a particle size of 30 mesh or larger.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) The present invention is directed to a material having good heat resistance and mechanical properties at high temperatures, and particularly excellent behavior for soft metals such as aluminum and brass. The present invention relates to a heat-resistant resin composition for molding.

(Prior Art) Asbestos fibers have conventionally been used as base materials for molding materials and friction agents with excellent heat resistance. but,
In recent years, the use of asbestos has been banned as it is considered harmful. Regarding sliding properties, carbon fiber is effective for VJ and quality metals such as steel, but aluminum,
There is a problem that carbon ta fibers have a large amount of wear and poor sliding properties against soft metals such as brass. Furthermore, although thermosetting phenolic resins and epoxy resins are the mainstream binder resins, they still lack heat resistance and are limited in their use under high load conditions.

(Problems to be Solved by the Invention) The present invention has been made in view of the above-mentioned circumstances. It is intended to provide a composition.

[Configuration of the invention (Means and actions for solving the problem) The inventors
As a result of extensive research aimed at achieving the above objectives, we have discovered that a resin composition consisting of a thermosetting resin and a composite filler, which will be described later, has heat resistance, mechanical properties at high temperatures, and sliding properties on soft metals. This discovery led to the completion of the present invention. That is, the present invention provides (A) (a) -
Numerical formula (in the formula, R1 is an organic group of Nli[j, x', x2 is the same or different monovalent atom or group selected from a hydrogen atom, a halogen atom, or an organic group, and n is an integer of 2 or more, respectively) Polymaleimides represented by (b) - formula (in the formula, R2 represents a monovalent atom or group selected from a hydrogen atom, a halogen atom, or an i group, and m represents an integer of 1 to 5, respectively) A thermosetting resin 30 containing as essential components an addition reaction product with aminophenol represented by (C) an epoxy compound having two or more epoxy groups in one molecule, and (d) polyp-vinylphenol. ~70% by weight and <8>(0)
Composite filler 30 containing 50-83% by weight of fluororesin and (f) 5-38% by weight of aromatic polyamide powder
This is a heat-resistant resin composition for molding, characterized in that it consists of 70% by weight.

Examples of the polymaleimide (a), which is one of the essential components of <A) thermosetting resin used in the present invention, include ethylene bismaleimide, hexamethylene bismaleimide, l- or p-phenylene bismaleimide, 4.4 '-diphenylmethane bismaleimide, 4.41-diphenyl ether bismaleimide, 4.4'-diphenylsulfone bismaleimide, 4.4'-dicyclohexylmethane bismaleimide, t- or p-xylylene bismaleimide, 4.4'-phenylene bismaleimide Examples include maleimide, and these may be used alone or in combination of two or more. In addition, if necessary, N
A small amount of monomaleimide such as -3-chlorophenylmaleimide or N-4-nitrophenylmaleimide can be used in combination.

In addition, the essential component (b) amine phenol is 0-,
Examples include m-1 or p-aminophenol and amine cresol, aminoxylenol containing various substituent isomers, amic 1m) L/phenol, aminobromophenol, aminocatechol, amylzorcine, aminooxybenzoic acid, etc. Or use a mixture of two or more.

In the present invention, an addition reaction product is obtained by reacting polymaleimides and aminophenols, and the blending ratio of each is (a) 1 ooam part of polymaleimide and (b) 5 to 40 parts by weight of aminophenol. part, more preferably 10 to 30 parts by weight. If the amine phenol is less than 5 parts by weight, the addition reaction product and (C) described below
The compatibility with the epoxy compound and (d'') poly p-vinylphenol is insufficient, and on the other hand, if the blending amount of aminophenol exceeds 40%, the amino groups become excessive and the heat resistance of the resin decreases. Not preferred. The temperature of the addition reaction is - generally 50 to 200°C, more preferably 80 to 1
The temperature is 80° C., and the reaction time can be arbitrarily selected from several minutes to several tens of hours depending on the reaction components.

The essential component (C) used in the present invention is an epoxy compound having two or more epoxy groups in one molecule, such as bisphenol A epoxy resin, sphenol F epoxy resin, novolak epoxy resin, and glycidyl polycarboxylic acid. Ester resins, polyglycidyl ethers of polyols, urethane-modified epoxy resins, aliphatic or alicyclic polyepoxides obtained by epoxidizing unsaturated compounds, epoxy resins with heterocycles, epoxy resins with heterocycles, glycidylated amines Examples include epoxy resins, which can be used alone or in combination of two or more.

The other essential component (d) poly-p-vinylphenol used in the present invention is, for example, one obtained by dehydrogenating and thermally polymerizing p-vinylphenol, and has a molecular weight of 12,500 yen.
~8,000 and a fi of about 120 per hydroxyl group is preferable. There are no particular restrictions on the method for synthesizing polyp-vinylphenol, and the method is not particularly limited to the above method. For the purpose of improving the heat resistance of the resin composition, part or all of the poly p-vinylphenol can be replaced with a bromide of poly p-vinylphenol. The blending ratio of the polymaleimide-aminophenol addition reaction product, epoxy resin, and polyp-vinylphenol can be varied over a wide range depending on the use and purpose. The blending ratio of the polymaleimide-aminophenol addition reaction product is preferably 30 to 80% by weight in the thermosetting resin. When the proportion is less than 30% by weight, heat resistance deteriorates, and when it exceeds 80% by weight, although heat resistance is sufficient, mechanical strength decreases, which is not preferable. The blending ratio of poly p-vinylphenol is 1 hydroxyl equivalent (b) for 1 epoxy equivalent <a>
) [(b)/(a)=1] is preferable, but practically the equivalent ratio is preferably in the range of 0.8 to 1.2.

There is no particular limitation on the order of mixing or reaction of the above-mentioned components, and a thermosetting resin having good curability and moldability and excellent heat resistance can be obtained.

However, usually first, (a) a polymaleimide and (b)
A product is obtained by addition reaction with amine phenol of
A thermosetting resin (A) is obtained by adding (C) an epoxy compound having two or more epoxy groups in one molecule and (d) poly p-vinylphenol.

Examples of the (e) fluororesin used as one component of the (B) composite filler used in the present invention include tetrafluoroethylene resin, fluorinated alkoxyethylene resin, fluorinated ethylene propylene ether resin, and tetrafluoroethylene hexafluoride resin. Examples include propylene copolymer resin and calcined Teflon powder. Examples of aromatic polyamide powder used as other components include Conex (manufactured by Teijin, trade name), and this powder preferably has a mesh size of 30 or more. Fluororesin and aromatic The blending ratio of polyamide powder is 50 to 8 fluororesin in the composite filler.
3% by weight, and 5-38% by weight of aromatic polyamide powder
It is preferable to contain. Less than 50% by weight of the fluororesin and less than 5% by weight of the aromatic polyamide powder have no effect on stagnation properties, and more than 83% by weight of the fluororesin and 38% by weight of the aromatic polyamide powder deteriorates heat resistance, which is not preferred.

Further, other components used include graphite, molybdenum disulfide, boron nitride, and the like.

Particularly when heat resistance is required, graphite is not preferred, so it is selected and added as appropriate. In addition, examples of the internal exfoliant include carnauba wax, higher saturated fatty acid ester, stearic acid, zinc stearate, etc., and these are added as necessary.

The heat-resistant resin composition for molding of the present invention includes the above-mentioned thermosetting resin 30-70 weight 96 weight composite filler 30-70 weight Φ
%, but the reason why these blending ratios are limited to the above range is that the thermosetting resin is 30% by weight.
If it is less than 70% by weight, workability and moldability are poor, and if it exceeds 70% by weight, a molded product that satisfies the required properties cannot be obtained. Furthermore, the resin composition of the present invention is thermosetting, and is generally cured by heating to a temperature of 150 to 250°C, but various additives may be added as necessary to further improve various properties. It can also be improved. For example, curing properties can be further improved by adding known curing catalysts such as acid anhydrides, boron fluoride complexes, tertiary amines, imidazoles, quaternary ammonium salts, and peroxides.

(Example) Next, the present invention will be specifically explained using examples.

Examples 1-6 N,N'-methylene bismaleimide, doaminophenol, epoxy resin, poly p-vinylphenol, 2-
Each component of ethyl-4-methylimidazole was selected at the lff1 composition ratio shown in Table 1, and a thermosetting resin was synthesized. A composite filler was added to the obtained thermosetting resin at the weight composition ratio shown in Table 1, and the mixture was uniformly stirred and mixed to obtain a heat-resistant resin composition for molding.

Comparative Examples 1 to 4 Resins and heat-resistant resin compositions for molding were obtained in the same manner as in the examples using the composition ratios shown in Table 1.

In this way, the heat-resistant resin compositions for molding obtained in Examples 1 to 6 and Comparative Examples 1 to 4 were molded using a pressure molding machine at a temperature of 2.
00~220℃, pressure ioo~300kaf/C12,
Pressure forming at a time of 1 to 2 minutes/mm, followed by 200 to
Various test moldings were made by curing at 230°C for 5 to 15 hours. The mechanical properties of this test molded article were measured according to JIS-6911. In addition, the sliding characteristics were measured using a thrust type 1f abrasion tester,
2CII12 (outer diameter 25.6φ.

Cylindrical shape with an inner diameter of 20.0φ, aluminum (A5052-BD) metal with a sliding area (3S finish), no lubrication, sliding speed 1m/sec, pressure ff110~5
The coefficient of dynamic friction was determined at 0 kc+f/cm2 (cumulative load after 10 minutes of operation at 10 kgf/cm2). Further, the amount of wear was measured after continuous operation for 24 hours under the conditions of a sliding speed of 0.30 m/sec and a load of 10 kof/cm2. These results are shown in Table 2, and the remarkable effects of the present invention were confirmed.

[Effects of the Invention] As is clear from the above explanation and Table 2, the heat-resistant resin composition for molding of the present invention has excellent heat resistance because it is a specific polyimide resin, and has excellent mechanical properties and sliding properties at high temperatures. In particular, it has excellent sliding properties on soft metals such as aluminum and brass, and also has good workability and moldability, and can be used in a wide range of applications such as active materials, friction materials, and electrical insulation materials.

Claims (1)

[Claims] 1 (A) (a) General formula ▲ Numerical formulas, chemical formulas, tables, etc. ▼ (In the formula, R^1 is an N-valent organic group, X^1 and X^2 are hydrogen atoms, (b) General formula ▲ Numerical formula, chemical formula, table, etc. ▼ (In the formula, R^2 represents a monovalent atom or group selected from a hydrogen atom, a halogen atom, or an organic group, and m represents an integer of 1 to 5, respectively) with an addition reaction product with an aminophenol; (c) an epoxy compound having two or more epoxy groups in one molecule; (d) 30 to 70% by weight of a thermosetting resin containing polyp-vinylphenol as an essential component; (B) (e) A heat-resistant resin composition for molding, comprising 50-83% by weight of a fluororesin and (f) 30-70% by weight of a composite filler containing 5-38% by weight of aromatic polyamide powder.