JP2002020582A - Phenolic resin molding material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a phenolic resin molding material filled with glass fiber and having improved mechanical properties, especially tensile strength. SOLUTION: The phenolic resin molding material contains (A) glass fibers having fiber diameter of 9-13 μm and fiber length of 1-6 mm and (B) glass fibers having fiber diameter of 15-25 μm and fiber length of 1-6 mm at a B/A ratio of 0.05-0.5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a glass fiber-filled phenolic resin molding material having excellent mechanical strength.

[0002]

2. Description of the Related Art Phenolic resin molding materials have been widely studied as alternatives to parts that have conventionally used many metals because of their excellent heat resistance, strength, dimensional stability, chemical resistance and the like.
Further, conventionally, glass fibers have been generally used as a filler in order to improve the properties of phenol molding materials, particularly, mechanical strength. In recent years, as component shapes have become smaller and more complex,
It is essential to further improve the performance of phenolic resin molding materials. However, it is difficult for conventional glass fiber-filled phenolic resin molding materials to sufficiently meet the required characteristics.

[0003]

SUMMARY OF THE INVENTION The present inventor has studied to improve mechanical strength among the above-mentioned required characteristics.
Conventionally, in a glass fiber-filled phenolic resin molding material, mechanical strength, particularly tensile strength, can be improved by using two specific glass fibers in combination.

[0004]

According to the present invention, there is provided a phenolic resin molding material filled with glass fiber, wherein (A) the fiber diameter is 9%.
Glass fibers having a fiber length of 1 to 6 mm and a fiber length of 1 to 6 mm, and a fiber diameter of 15 to 25 μm and a fiber length of 1 to 6 mm (B).
The present invention relates to a glass fiber-filled phenolic resin molding material, characterized in that the phenolic resin molding material has a molecular weight of 0.5.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The phenolic resin used in the present invention includes a solid novolak type phenolic resin and a solid resol type phenolic resin, and is not particularly limited.
Further, the glass fiber as the filler is (A) a fiber diameter of 9-1.
A chopped strand having a fiber length of 3 μm and a fiber length of 1 to 6 mm and a chopped strand (B) having a fiber diameter of 15 to 25 μm and a fiber length of 1 to 6 mm are used in combination.

[0006] The compounding amount of the compound will be described. The compounding amount of the phenolic resin is 25 to 40% by weight based on the whole molding material. If it exceeds 40% by weight, the ratio of the glass fiber becomes small, and a molded product having sufficient mechanical strength cannot be obtained. On the other hand, if the content is less than 25% by weight, it may be difficult to form a molding material or the flowability may be poor and the moldability may be reduced. Therefore, the above range is optimal.

The compounding amount of the glass fiber is 50 to 70% by weight based on the whole molding material. 50 glass fiber
When the amount is less than% by weight, the reinforcing effect for improving the mechanical properties is reduced. On the other hand, if it exceeds 70% by weight, the amount of the resin is inevitably reduced, so that it may be difficult to form a molding material or the moldability may be reduced. The use ratio (B) / (A) of the two types of glass fibers is 0.05 to
0.5. When this ratio is less than 0.05, the amount of fibers having a large glass fiber diameter decreases. Therefore, the effect of using glass fiber having a large fiber diameter is reduced, and the effect of improving mechanical properties is small. Moreover, the compounding amount of glass fiber is 50 to
In the range of 70% by weight, the number of fibers decreases as the amount of the glass fiber having a large fiber diameter increases, and when the combined ratio exceeds 0.5, the reinforcing effect for improving the mechanical strength by the glass fiber decreases. . The use ratio (B) / (A) of the two types of glass fibers is particularly preferably in the range of 0.05 to 0.3 because the tensile strength, the bending strength and the impact strength are improved in a well-balanced manner.

[0008] The phenolic resin molding material of the present invention is prepared by heating and melting and kneading a mixture of a resin, a filler and additives using a roll, a kneader, a twin-screw extruder or the like, and then cooling and pulverizing the mixture. can get.

[0009]

EXAMPLES Examples and comparative examples will be described below.
Table 1 shows the composition of the glass fiber-filled phenolic resin molding material and the results of measuring the mechanical strength of the molding material obtained in each example. In the glass fibers used in the examples, the glass fiber (A) has a glass fiber diameter of 11 μm and a fiber length of 3 mm, and the glass fiber (B) has a glass fiber diameter of 23 μm and a fiber length of 3 mm. Comparative Example 1 is a case where only the glass fiber (A) is used. Comparative Example 2 is a case where only the glass fiber (B) was used. In Examples 1 and 2, part of the glass fiber (A) of the comparative example was replaced with glass fiber (B), and the combination ratio (B) / (A) was 0.1 in Example 1 and Example 2
Is 0.3. The test pieces used for the evaluation were obtained by transfer molding. Further, the measurement of the mechanical strength was performed based on JIS K 6911.

[0010]

[Table 1] It can be seen that the phenolic resin molding material obtained in each example is superior in tensile strength, bending strength and impact strength as compared with the molding material obtained in the comparative example.

[0011]

According to the present invention, in a phenolic molding material filled with glass fiber, (A) glass fiber having a fiber diameter of 9 to 13 μm and a fiber length of 1 to 6 mm, and (B) fiber diameter of 15 to 25
By using a glass fiber having a fiber length of 1 to 6 mm in μm and two types of glass fibers having different fiber diameters in a specific ratio, it is possible to improve the mechanical strength, particularly the tensile strength, of the phenolic resin molding material. .

Claims (1)

[Claims] 1. A phenolic resin molding material filled with glass fiber, wherein (A) the fiber diameter is 9 to 13 μm and the fiber length is 1 to 1.
6 mm glass fiber, and (B) fiber diameter 15 to 25 μ
m, a glass fiber having a fiber length of 1 to 6 mm, wherein the usage ratio (B) / (A) is 0.05 to 0.5.