JPH0414699B2 - - Google Patents

Description

[Detailed description of the invention]

[Technical Field of the Invention] The present invention relates to a heat-resistant resin composition for molding that has excellent sliding properties, particularly on soft metals such as aluminum and brass. [Technical background of the invention and its problems] Asbestos fibers have conventionally been used as base materials for molding materials and friction materials with excellent heat resistance. However, the use of asbestos is currently prohibited because it is considered harmful. Regarding sliding properties, organic fibers are effective against hard metals such as steel, but organic fibers also have the disadvantage of high wear and poor sliding performance against soft metals such as aluminum and brass. It was hot. Furthermore, phenolic resins and epoxy resins are the mainstream resins for binders, but they lack heat resistance and are limited in their use under high load conditions. [Object of the Invention] The object of the present invention was made in view of the above-mentioned drawbacks, and it is an object of the present invention to provide a heat-resistant resin for molding that has excellent heat resistance, mechanical properties, and sliding properties, especially sliding properties on soft metals. It is intended to provide a composition. [Summary of the Invention] As a result of intensive research to achieve the above object, the present invention has been made based on the discovery that the above object can be achieved by using a thermosetting resin and a composite filler, which will be described later. be. That is, the present invention provides (A) (a) represented by the general formula ()
Addition reaction product between polymaleimide and (b) aminophenol represented by general formula () (However, in the formula, R ¹ is an n-valent organic group, X ¹ and X ² are the same or different monovalent atoms or groups selected from hydrogen atoms, halogen atoms, or organic groups, and n is an integer of 2 or more. (Represented respectively.) (However, in the formula, R ² is a monovalent atom or group selected from a hydrogen atom, a halogen atom, or an organic group, and m is 1
Each represents an integer between ~5. ) (c) Thermosetting resin 30 whose essential component is an epoxy compound having two or more epoxy groups in one molecule
~70% by weight, and 70 to 30% by weight of a composite filler whose essential components are (B)(d) fluororesin and (e) granular phenolic resin. It is a thing. Examples of the (a) polymaleimide which is one of the essential components of the thermosetting resin (A) in the present invention include ethylene bismaleimide, hexamethylene bismaleimide, m- or p-phenylene bismaleimide, 4,
4'-diphenylmethane bismaleimide, 4,4'-
Diphenyl ether bismaleimide, 4,4'-diphenylsulfone bismaleimide, 4,4'-dichlorohexylmethane bismaleimide, m- or p
-xylylene bismaleimide, 4,4'-diphenylene bismaleimide, etc., and these may be used alone or in combination of two or more. Further, if necessary, a small amount of monomaleimide such as N-3-chlorophenylmaleimide or N-4-nitrophenylmaleimide can be used in combination with these polymaleimides. As the essential component (b) aminophenol, o
-, m- or p-aminophenol and aminocresol, aminooxylenol including various substituent isomers, aminochlorophenol, aminobromophenol, aminocatechol, aminoresorcinol, aminobis(hydroxyphenol)propane, aminooxybenzoic acid, etc. These can be used alone or in combination of two or more. One or more types of each of (a) polymaleimides and (b) aminophenols are selected and reacted to obtain an addition reaction product, but the blending ratio of each is as follows:
(b) 5 to 40 parts by weight, more preferably 10 parts by weight of the aminophenol (b) per 100 parts by weight of the (a) polymaleimide.
A proportion of ~30 parts by weight is required. (b) If the amount of aminophenol is less than 5 parts by weight, the addition reaction product and the epoxy compound described below will not have sufficient compatibility;
If the amount exceeds 1 part by weight, the amino groups become excessive and the heat resistance of the resin decreases, which is not preferable. The addition reaction temperature is generally 50 to 200°C, more preferably 80 to 180°C, and the reaction time is from several minutes to several minutes.
The time period can be arbitrarily selected within the range of 10 hours depending on the reaction components. The essential component (c) which is mixed with the addition reaction product thus obtained is a compound having two or more epoxy groups in one molecule, such as bisphenol A epoxy resin, bisphenol F epoxy resin, novolac epoxy resins, polyglycidyl esters of polycarboxylic acids, polyglycidyl ethers of polyols, urethane-modified epoxy resins, aliphatic or alicyclic polyepoxides epoxidized with unsaturated compounds, epoxy resins with multiple rings, different types Examples include epoxy resins having rings and epoxy resins in which amines are glycidylated, and one or more of these may be selected and used. An addition reaction product of polymaleimide and aminophenol and an epoxy resin are used to form (A) a thermosetting resin, but an addition reaction product of polymaleimide and aminophenol,
There are preferable conditions for the blending ratio of the epoxy compound, and it is desirable that the addition reaction product be 30 to 80% by weight and the epoxy compound be 70 to 20% by weight. If the addition reaction product is less than 30% by weight, the heat resistance will not be sufficient;
If it exceeds 80% by weight, the heat resistance will be sufficient but the mechanical strength will decrease, which is not preferable. In this blending range,
A thermosetting resin with good curability and moldability and excellent heat resistance can be obtained without limiting the order of mixing or reaction. However, in the usual case, first an addition reaction is carried out between the polymaleimide (a) and the aminophenol (b) to obtain an addition reaction product, which is then added to the addition reaction product containing two or more epoxy groups in one molecule of (c). By mixing an epoxy compound, the thermosetting resin (A) can be obtained. Therefore, the composition of the present invention comprises (B) a composite comprising (A) the thermosetting resin obtained as described above, (d) a fluororesin, and (e) a granular phenolic resin as essential components. It is obtained by uniformly mixing and kneading fillers. Examples of the fluororesin (d) which is an essential component of the composite filler (B) used in the present invention include tetrafluoroethylene resin, fluoride alkoxyethylene resin, fluoride ethylene propylene ether resin, and tetrafluoroethylene propylene ether resin. Examples include hexafluoropropylene copolymer resin and fired fluororesin powder, and these may be used alone or in combination of two or more. Examples of the granular phenolic resin (e), which is another essential component, include Bell Pearl R-900, Bell Pearl S-930, Bell Pearl S-970 (trade name manufactured by Kanebo Co., Ltd.), which may be used alone or in combination. Use by mixing more than one species. The blending ratio of the fluororesin (d) and the granular phenolic resin (e) is:
It is preferable that the fluororesin and granular phenolic resins contain 50 to 83% by weight and 5 to 38% by weight of the composite additive (B). If the fluororesin is less than 50% by weight or less than 5% by weight of the particulate phenolic resin, there is no effect on sliding properties, and if it exceeds 83% or 38% by weight, heat resistance deteriorates, which is not preferable. Further, other components of the composite filler (B) include graphite, molybdenum disulfide, boron nitride, and the like. Particularly when heat insulation is required, graphite is not preferred, so it is added as appropriate. In addition, examples of internal mold release agents include carnauba wax, higher saturated fatty acid esters, stearic acid, zinc stearate, and other components may be added as necessary. As described above, the heat-resistant resin composition for molding of the present invention is characterized by comprising (A) 30 to 70% by weight of a thermosetting resin and (B) 70 to 30% by weight of a composite filler. The reason for limiting the blending ratio to the above range is that (A) thermosetting resin less than 30% by weight will result in poor workability and moldability, and if it exceeds 70% by weight, a molded product that satisfies the required properties will not be obtained. It's for a reason. Further, the resin composition of the present invention is thermosetting,
Generally, it is cured by heating to a temperature of 150 to 250°C, but if necessary, various additives can be added to further improve various properties. For example, curing properties can be further improved by adding a curing catalyst such as a known acid anhydride, boron fluoride complex, tertiary amine, imidazole, quaternary ammonium salt, or peroxide. [Examples of the Invention] The present invention will be specifically described below with reference to Examples. Examples 1-6 N,N'-methylenebisphenylmaleimide,
Each compounded component of m-aminophenol, epoxy resin, and 2-ethyl-4-methylimitazole was added to the first
A thermosetting resin was synthesized by selecting the weight composition ratio shown in the table. Using the obtained resin, a composite filler was blended in the weight composition ratio shown in Table 1, and the mixture was uniformly stirred and kneaded to obtain a heat-resistant resin composition for molding. Comparative Examples 1 to 4 Resin compositions were obtained in the same manner as in the examples using the composition ratios shown in Table 1. In this way, the resin compositions obtained in Examples 1 to 6 and Comparative Examples 1 to 4 were molded using a pressure molding machine at a temperature of 200 to 220.
℃, a pressure of 100 to 300 kg/cm ² , and a time of 1 to 2 minutes/mm per mm, followed by a curing treatment at 200 to 230° C. for 5 to 15 hours to produce molded products for various tests. Regarding the mechanical properties of this test molding, please refer to JIS-
Measured according to K-6911. In addition, the sliding properties were measured using a thrust type friction and wear tester under the conditions of 2 cm ²
(Ring shape with outer diameter 25.6φ and inner diameter 20.0φ, 3S finish) Made of aluminum metal with a sliding surface area ^of
The coefficient of dynamic friction was determined using the cumulative load (after 10 minutes of operation at ^cm2 ). In addition, the sliding speed is 0.3cm/sec, and the load is 10Kg/ ^cm2.
The amount of wear was measured after continuous operation for 24 hours under these conditions. The results are shown in Table 1.

【table】

【table】

[Table] [Effects of the invention] The heat-resistant resin composition for molding of the present invention has heat resistance,
It not only has excellent mechanical properties, especially sliding properties against soft metals such as aluminum and brass, but also has good workability and moldability, and can be used in a wide range of applications such as sliding materials, friction materials, and electrical insulation materials. can.

Claims (1)

[Scope of Claims] 1 (A) An addition reaction product of (a) a polymaleimide represented by the general formula () and (b) an aminophenol represented by the general formula (), and two in one molecule. 30 to 70% by weight of a thermosetting resin containing (c) an epoxy compound having the above epoxy groups as an essential component; (However, in the formula, R ¹ is an n-valent organic group, X ¹ and X ² are the same or different monovalent atoms or groups selected from hydrogen atoms, halogen atoms, or organic groups, and n is 2
each of the above integers) (However, in the formula, R ² represents a monovalent atom or group selected from a hydrogen atom, a halogen atom, or an organic group, m
represent integers from 1 to 5, respectively) Heat-resistant resin composition. 2 In the composite filler of (B), 50% of the fluororesin of (d)
The heat-resistant resin composition for molding according to claim 1, characterized in that it contains the granular phenolic resin (e) in an amount of 5 to 38% by weight.