JPH0249341B2 - FUENOORUJUSHISEIKEIZAIRYO - Google Patents

Description

[Detailed description of the invention]

[Technical Field of the Invention] The present invention relates to a phenolic resin molding material that has excellent heat resistance, mechanical strength, abrasion resistance, and electrical properties. [Technical background of the invention and its problems] Phenol resin is a filler, a plasticizer, a colorant,
It is widely used as a molding material mixed and kneaded with mold release agents. Generally, phenolic resin molding materials use wood flour as the main filler, so they have drawbacks such as heat resistance, mechanical strength, and abrasion resistance. To improve this drawback, there are methods using inorganic materials such as asbestos, calcium carbonate, and talc as fillers. Although this improves heat resistance, it has drawbacks in mechanical strength and wear resistance. In an attempt to improve this, there are methods using graphite and molybdenum disulfide as fillers, but although the wear resistance is improved, there are drawbacks in mechanical strength and electrical properties. In an attempt to improve this, products using glass fiber as a filler had high heat resistance and mechanical strength, but had drawbacks in abrasion resistance (especially abrasion of the mating metal material). Furthermore, those using natural organic fibers as fillers have good mechanical strength and abrasion resistance, but lack heat resistance. Excellent heat resistance in such situations,
There was a need for a phenolic resin molding material with well-balanced mechanical strength, wear resistance and electrical properties. [Object of the Invention] An object of the present invention is to provide a well-balanced phenolic resin molding material with excellent heat resistance, mechanical strength, abrasion resistance, and electrical properties that eliminates the above-mentioned drawbacks. [Summary of the Invention] In the present invention, as a result of intensive research to achieve the above-mentioned object, it was discovered that a molding material described below has the above-mentioned desired characteristics. That is, the present invention mainly comprises (a) one or more resins selected from phenolic resins, xylene resins, and xylene-modified phenolic resins, (b) glass fibers, (c) natural organic fibers, and (d) boron nitride. A phenolic resin molding material characterized by containing 5 to 40% glass fiber in the molding material.
It is a well-balanced phenolic resin molding material containing 5-30% by weight of natural organic fibers and 1-30% by weight of boron nitride, and has excellent heat resistance, mechanical strength, abrasion resistance, and electrical properties. The one or more resins selected from (a) phenolic resins, xylene resins and xylene-modified phenolic resins used in the present invention include the following. As the phenolic resin, for example, phenols such as phenol and cresol, or phenols modified with molasses, lignin, xylene, naphthalene, or petroleum aromatic hydrocarbons, and formalin or paraformaldehyde are blended in an appropriate molar ratio. , a novolak-type phenolic resin initial condensate, a resol-type phenolic resin initial condensate, and a mixture of a novolak-type phenolic resin initial condensate and a resol-type phenolic resin initial condensate, which are obtained by reaction under a catalyst. Examples of the xylene resin or xylene-modified phenol resin include xylene formaldehyde resin or xylene-modified phenol resin obtained by reacting xylene formaldehyde resin with phenol or alkylphenol. The glass fiber (b) used in the present invention is 2-
0.1~25 strands of single fibers with a diameter of 30μ
Examples include those cut into mm. In addition, (c) natural organic fibers used in the present invention include cotton flock, α-cellulose, flax, hemp,
Examples include jute, cotton woven fabric, and fluff powder. Furthermore, as (d) boron nitride used in the present invention, there is, for example, boron nitride manufactured by Denki Kagaku Kogyo Co., Ltd. As mentioned above, the present invention comprises (a) one or more resins selected from phenolic resins, xylene resins, and xylene-modified phenolic resins, (b) glass fibers, (c) organic natural fibers, (d) This is a phenolic resin molding material whose main component is boron nitride, and the blending ratio of each component will be explained below. The blending ratio of glass fiber is 5% to the molding material.
If the content is less than 5% by weight, the mechanical strength will be weak, and if it exceeds 40% by weight, the abrasion resistance will be poor, which is not preferred. It is preferably 15 to 25% by weight. The blending ratio of natural organic fibers is 5 to 30% by weight based on the molding material. If it is less than 5% by weight, the mechanical strength will be weak, and if it exceeds 30% by weight, the heat resistance will be poor, which is not preferable. It is preferably within the range of 8 to 20% by weight. The blending ratio of boron nitride is 1 to 30% by weight based on the molding material. If it is less than 1% by weight, it has no effect on wear resistance and heat resistance, and if it exceeds 30% by weight, the mechanical strength is poor, which is not preferable. Therefore, each component is limited within the above range. In addition to the above, the phenolic resin molding material of the present invention may contain additives such as a curing agent, a coloring agent, a curing accelerator, a flame retardant, a mold release agent, a lubricant, a coupling agent, a plasticizer, etc., as necessary. Can be done. The molding material of the present invention is usually produced as follows. A predetermined amount of resin, glass fiber, natural organic fiber, and boron nitride, as well as curing agents and other additives as necessary, are added and mixed, uniformly dispersed, heated and kneaded in a kneader, and then cooled and solidified. It is crushed into an appropriate size using a crusher to obtain a phenolic resin molding material. [Effects of the Invention] The phenolic resin molding material of the present invention has high heat resistance, high mechanical strength, excellent wear resistance and electrical properties, and is an extremely well-balanced molding material. [Examples of the Invention] Hereinafter, the present invention will be specifically explained with reference to Examples, but the present invention is not limited to these Examples. Hereinafter, "%" means "% by weight". Example 1 45% novolac type phenolic resin, 7% hexamethylenetetramine, 20% glass fiber, 10% cotton flock, 10% boron nitride, and 8% other additives were mixed at room temperature and kneaded at 90 to 110°C. After cooling, the mixture was pulverized to obtain a phenolic resin molding material. The obtained molding material was molded and cured in a mold heated to 170°C by compression molding and injection molding to obtain a molded product. Various properties of this molded article were measured and are shown in Table 1. Example 2 40% novolac type phenolic resin, 5% xylene-modified phenolic resin, 7% hexamethylenetetramine, 20% glass fiber, 10% cotton flock, 10% boron nitride, and 8% other additives were mixed at room temperature, After kneading at 90 to 110°C, the mixture was cooled and pulverized to obtain a phenolic resin molding material. A molded article was made from the obtained molding material in the same manner as in Example 1, and its properties were measured and are shown in Table 1. Example 3 50% resol type phenolic resin, 15% glass fiber
%, 15% cotton woven fabric, 15% boron nitride, and 5% other additives were obtained in the same manner as in Example 1, and then molded products were made and their properties were measured, as shown in Table 1. Ta. Comparative Example 1 50% novolac type phenolic resin, 8% hexamethylenetetramine, 35% wood flour, and 7% other additives.
A molding material was obtained by the same method as in Example 1,
Next, we made a molded product and measured its characteristics, so the first step was to
Shown in the table. Comparative Example 2 40% resol type phenolic resin, 10% xylene modified phenolic resin, 15% glass fiber, 15% cotton woven fabric
%, 15% kaolin clay, and 5% other additives to obtain a molding material in the same manner as in the example. Next, molded products were made and their properties were measured and are shown in Table 1.

[Table] As is clear from Table 1, the phenolic resin molding material of the present invention was found to be excellent in heat resistance, mechanical strength, abrasion resistance, and electrical properties.

Claims (1)

[Scope of Claims] 1 (a) 1 selected from phenolic resins, xylene resins, and xylene-modified phenolic resins;
A phenolic resin molding material characterized in that the main component is a species or two or more kinds of resins (b) glass fibers (c) natural organic fibers (d) boron nitride. 2 Glass fiber 5-40% by weight based on the molding material,
The phenolic resin molding material according to claim 1, characterized in that it contains 5 to 30% by weight of natural organic fibers and 1 to 30% by weight of boron nitride.