JPH06322232A - Phenolic resin molding material - Google Patents

Abstract

PURPOSE:To obtain a phenolic resin molding material improved in bending strength, heat resistance and wear resistance and reduced in a tendency toward wearing aluminum by mixing a glass fiber with a natural organic fiber, a silica powder, a lubricating thermoplastic resin and a vinyl acetate resin. CONSTITUTION:The material is prepared by mixing a novolac or resol phenolic resin with 40-80wt.% glass fiber, 5-20wt.% natural organic fiber of a fiber length of 1mm or below, 5-15wt.% silica powder of a particle diameter of 20mum or below, 5-25wt.% lubricating thermoplastic resin of a melting point of 400 deg.C or below and a particle diameter of 50mum or below and 40-65wt.% thermoplastic resin comprising vinyl acetate resin.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a phenolic resin molding material, which is characterized in that glass fiber, organic natural fiber, silica powder and thermoplastic resin are blended with a novolac type or resol type phenolic resin. The present invention relates to a resin molding material.

[0002]

2. Description of the Related Art Conventionally, a molded product obtained by molding a phenolic resin molding material, which is a mixture of an organic natural fiber such as pulp, cloth strips, crushed cloth, and a phenol resin, has excellent wear characteristics In the automobile field, it has been used for various switch parts, transmission parts, etc. However, from the viewpoint of improving heat resistance and strength of parts used in the automobile field and the like, materials having higher heat resistance and strength have been desired. Many phenol resin molding materials having high strength and high heat resistance, which are glass fibers or a mixture of glass fibers and an inorganic filler, are on the market, but they have problems in abrasion resistance. Glass fibers have an excellent effect in improving the strength and heat resistance, but the wear characteristics deteriorate in inverse proportion to the amount added. In particular, in the automobile field, it is often used by replacing iron, aluminum, etc., where they were originally used, which not only wears the molded product, but also wears the other materials, iron and aluminum. .

[0003]

DISCLOSURE OF THE INVENTION The present inventor does not impair the heat resistance and strength, which are the features of glass-added phenol resin molding materials, by blending glass-blended phenol resin with organic natural fibers and silica powder. It has been found that the wear characteristics are improved (see Japanese Patent Laid-Open No. 60-124646). Further, the present inventor has conducted extensive research and found that the addition of a specific thermoplastic resin to the above system further improves the wear resistance property, and has completed the present invention.

[0004]

SUMMARY OF THE INVENTION The present invention is a glass fiber,
The total amount of organic natural fibers, silica powder, and thermoplastic resin consisting of a lubricating thermoplastic resin and vinyl acetate resin is 4
0 to 65% by weight, and each component of the above four components is 40 to 80/5 to 20/5 to 15 / with respect to the total amount of these components.
The present invention relates to a phenol resin molding material, which is compounded in an amount of 5 to 25% by weight. The phenol resin used here may be novolac or resol, or those modified with these may be used. If necessary, two or more of these may be used in combination.

Next, the filler will be described. The glass fiber used here may be any chopped strand that is usually used for molding materials. Organic natural fibers include defibrated pulp, powdered pulp, raw cotton pulp,
Although a crushed cloth or the like can be used, a fine fiber having a fiber length of 1 mm or less is preferable in view of the defibration degree when the material is made into a molding material, the degree of dispersion, the bulkiness of the molding material, and the like. Silica powder
Both natural silica and synthetic silica have the effect of improving wear resistance, but fine particles having a particle size of 20 μm or less are particularly preferable. Although various kinds of thermoplastic resins can be used, particularly the desired excellent wear characteristics can be obtained by using the following two components in combination.

As the first component, a polyolefin such as polyethylene or a lubricating resin such as a fluorine resin such as a tetrafluoroethylene resin can be used. Although the molecular weight is not particularly specified, a polymer having a high molecular weight is effective to the extent that compatibility with the phenolic resin, dispersibility, and workability during materialization are not impaired. Considering these, it is desirable that the polyethylene resin has a melting point of 120 ° C. or less and a particle size of 50 μm or less and the tetrafluoroethylene resin has a melting point of 400 ° C. or less and a particle size of 50 μm or less. The first component here serves to form a film on the surface of the molded product and reduce the wear coefficient. As the second component, a vinyl acetate resin is used, but a liquid one having a polymerization degree of 200 or less and a solid one having a polymerization degree of 200 or more can be used. Further, the presence or absence of modification such as ethylene copolymerization and acrylic copolymerization does not matter. Considering workability in forming a molding material, a solid vinyl acetate resin having a degree of polymerization of about 5000 is preferably pulverized into a powder. The vinyl acetate resin serves to prevent the static strength such as bending strength and tensile strength from being lowered by adding the organic natural fiber, the silica-like powder and the thermoplastic resin component of the first component. The combination ratio of the first component and the second component is not particularly limited, but is preferably 20 to 50/50 to 80% by weight from the viewpoint of balance of wear characteristic strength.

If the composition of these fillers is 65% by weight or more with respect to the total amount of the molding material, it is difficult to make them into molding materials,
If the content is less than 10% by weight, the flowability of the molding material, the heat resistance of the molded product, the strength, the dimensional stability and the like will be problematic. Therefore, the content of the filler is preferably 40 to 65% by weight. A method of forming a molding material is a method of using a roll, a co-kneader, an extruder, etc., for a blend of a resin, a filler, an additive, etc., after heating and melting and kneading, and then pelletizing or cooling and pulverizing the material, or There is a method in which a varnish is added to the filler and the additive and the mixture is stirred by using a Henschel mixer, a super mixer or the like to impregnate the filler with the resin, and then the solvent is removed to form the material. In any of the manufacturing methods, if the above composition, a molding material having excellent wear resistance can be obtained, but from the viewpoint of heat resistance, a molding material having a small residual volatile content can be obtained with a roll, a co-kneader, or an extruder. It is desirable to manufacture. A molding having excellent heat resistance, abrasion resistance and strength can be obtained by heating, pressurizing and curing the molding material obtained as described above by a usual molding method.

[0008]

EXAMPLES Next, the present invention will be explained based on Examples and Comparative Examples. Here, "part" means "part by weight". Example 1 (A) Novolak type phenolic resin having a weight average molecular weight of 5000 (charged molar ratio 0.83, hydrochloric acid catalyst, O / P ratio 0.75) 35 parts (B) hexamethylenetetramine 6 (C) glass fiber (Nippon Electric Glass) (1.5 mm length) 40 (D) crushed cloth (1 mm pass) 5 (E) amorphous silica (Nippon Silica Industry Co., Ltd. primary particle size of about 16 nm) 5 (F) PTFE (Kitamura melting point 320) (° C, particle size 30 μm) 2 (G) Vinyl acetate resin (Nippon Gosei Kagaku Kogyo Co., Ltd., degree of polymerization: 5000) 5 (H) Curing accelerator, mold release material, pigment, etc. 4 are mixed and heated and kneaded with a dry roll to mold. The material was manufactured.

Example 2 (A) Novolak type phenol resin having a weight average molecular weight of 6500 (charged molar ratio 0.88, oxalic acid catalyst, O / P ratio 0.8) 40 parts (B) hexamethylenetetramine 7 (C) glass fiber ( Nippon Electric Glass Co., Ltd. 1.5 mm length 35 (D) Crushed cloth (1 mm pass) 7 (E) Amorphous silica (Nippon Silica Industry Co., Ltd. primary particle size of about 16 nm) 7 (F) Polyethylene (Sumitomo Seika (Melting point: 105 ° C, particle size: 25 μm) 1 (G) Liquid vinyl acetate resin (Nippon Gosei Kagaku Kogyo Co., Ltd., degree of polymerization: 200) 3 (H) Extruder compounded with 5 curing accelerators, release agents, pigments, etc. And melt-kneaded to produce a molding material.
Example 3 (A) Dimethylene ether resol type phenolic resin (Sumitomo Dures Co., Ltd. PR-53529) 30 parts (B) Novolac type phenolic resin having a weight average molecular weight of 6500 8 (C) Glass fiber (Nippon Electric Glass ( 35 mm (D) Crushed cloth (1 mm pass) 7 (E) Amorphous silica (Nippon Silica Industry Co., Ltd. primary particle size of about 16 nm) 7 (F) Polyethylene (Sumitomo Seika Chemical Co., Ltd. melting point 105 ° C., particle size 25 μm) 1 (G) Liquid vinyl acetate resin (Nippon Gosei Kagaku Kogyo Co., Ltd., degree of polymerization: 200) 5 (H) Curing accelerator, release agent, pigment, etc. 5 are mixed and melt-kneaded in an extruder. Then, the mixture was pelletized with a granulator to produce a molding material.

Comparative Example 1 (A) Novolak type phenol resin having a weight average molecular weight of 5000 (charged molar ratio 0.83, hydrochloric acid catalyst, O / P ratio 0.75) 35 parts (B) hexamethylenetetramine 6 (C) glass fiber ( (Nippon Electric Glass Co., Ltd., 1.5 mm long) 55 (D) A curing accelerator, a release agent, a pigment and the like 4 were blended and heated and kneaded with a dry roll to produce a molding material. << Comparative Example 2 >> (A) Novolak type phenolic resin having a weight average molecular weight of 5000 (charge molar ratio 0.83, hydrochloric acid catalyst, O / P ratio 0.75) 42 parts (B) hexamethylenetetramine 7 (C) glass fiber (Nippon Electric Glass Co., Ltd. 1.5 mm length) 40 (D) Crushed cloth (1 mm pass) 5 (E) Amorphous silica (Nippon Silica Industry Co., Ltd. primary particle size of about 16 nm) 5 (F) Curing accelerator, release agent, pigment Other 4 was blended and heated and kneaded with a dry roll to produce a molding material.

Comparative Example 3 (A) Novolak type phenolic resin having a weight average molecular weight of 5000 (charge molar ratio 0.83, hydrochloric acid catalyst, O / P ratio 0.75) 40 parts (B) hexamethylenetetramine 7 (C) glass fiber ( Nippon Electric Glass Co., Ltd. 1.5 mm length 40 (D) Crushed cloth (1 mm pass) 5 (E) Amorphous silica (Nippon Silica Industry Co., Ltd. primary particle size of about 16 nm) 5 (F) PTFE (Co., Ltd.) Kitamura melting point 320 ° C., particle size 30 μm) 2 (G) A curing accelerator, a release agent, a pigment and the like 4 were blended and heated and kneaded with a dry roll to produce a molding material. Bending strength, Charpy impact strength, and Suzuki type abrasion test (counterpart material: aluminum) were evaluated for Examples 1 to 3 and Comparative Examples 1 to 3, and the results are shown in Tables 1 and 2.
Shown in.

[0012]

[Table 1]

[0013]

[Table 2]

(Measurement method) Bending strength, Charpy impact strength: Heat deformation temperature according to JIS K 6911: Wear amount according to ASTM D 648 (Suzuki type wear test): Load 20 Kg, peripheral speed 50 mm /
sec, time 4 hours The molding materials obtained in Examples 1 to 3 have excellent flexural strength and heat resistance, and are very excellent in wear resistance and aluminum wear resistance of the molding itself. can get.
Comparative Example 1 is a case where only glass fiber is used as the filler, and the bending strength is large, but the abrasion of the molded product itself and aluminum is very large. In Comparative Example 2, when the thermoplastic resin is not added, the wear of the molded product itself is greatly improved, but the wear amount of aluminum is not significantly improved and the bending strength is also reduced. Comparative Example 3 is a case in which vinyl acetate is not added among the thermoplastic resins, but although the wear characteristics are improved, the bending strength is reduced.

[0015]

EFFECTS OF THE INVENTION As is clear from the above examples, the molding material of the present invention has excellent flexural strength and heat resistance while being extremely excellent in wear resistance and aluminum wear resistance of the molding itself. A molded product can be obtained.

Claims (1)

[Claims] 1. A glass fiber, an organic natural fiber, a silica powder, and a thermoplastic resin comprising a lubricating thermoplastic resin and a vinyl acetate resin are contained in an amount of 40 to 65% by weight based on the total amount, and each of the four components is contained. A phenol resin molding material, which is blended so as to be 40 to 80/5 to 20/5 to 15/5 to 25% by weight with respect to the total amount of these components.