JPH01272662A - Polyamide resin composition - Google Patents

Abstract

PURPOSE:To obtain a resin composition having excellent hot strength and thermal aging resistance, comprising a polyamide consisting of xylylenediamine and an alpha,omega-straight-chain aliphatic dibasic acid, nylon 66, powdery thermosetting resin having specific particle diameter and glass fibers. CONSTITUTION:(A) 100 pts.wt. mixture of A1: 20-99 pts.wt. polyamide resin obtained from xylylenediamine (>=60% m-xylylenediamine) and an alpha,beta-straight- chain aliphatic dibasic acid (preferably adipic acid or sebasic acid) and A2: 80-1 pts.wt. nylon 66 is blended with (B) 5-85 pts.wt., preferably 10-50 pts.wt. powdery thermosetting resin (preferably phenolic resin or xylene resin, especially phenolic resin containing 0.5-10 wt.% methylol group) having 1-800mum, preferably 1-10mum particle diameter and (C) 5-300 pts.wt., preferably 10-250 pts.wt. glass fibers to give a resin composition.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a polyamide resin composition for molding. More specifically, the present invention relates to a polyamide resin composition for molding that has excellent hot strength, heat aging resistance, mechanical properties, electrical properties, and dimensional stability, and has low water absorption.

[Prior Art] Polyamide resin (hereinafter sometimes abbreviated as "MX nylon") obtained from xylylene diamine and α,ω-direct button aliphatic dibasic acid has excellent mechanical properties and electrical properties. It has physical properties, dimensional stability, chemical resistance, etc., and has low water absorption, so it is used in various molding materials.

However, when Mx nylon is used as a mechanical material such as automobile engine covers, xylencers, and connectors that require particularly high hot strength and heat aging resistance, these properties are insufficient and it is still not suitable for practical use. It hasn't arrived yet.

Generally, in order to improve the heat aging resistance of polyamide resin,
Methods of blending copper compounds or phenol-based or phosphite-based antioxidants, and methods of blending glass fibers and other inorganic fillers to improve hot strength are known, but MX In the case of nylon, these formulations do not improve performance as much as expected.

JP-A-58-141234 and JP-A-58-
Japanese Patent No. 152046 discloses a resin composition in which a granular or powdery phenol/formaldehyde resin is blended with a thermal ijJ plastic resin such as a polyolefin resin, polystyrene resin, acrylic resin, or polyamide resin. In these publications, polyamide resins such as ordinary nylon 6 and nylon 66 resins are listed as polyamide resins among thermoplastic resins, and it is also disclosed that the heat distortion temperature, volume resistivity value by boiling, and compressive strength can be improved. However, a practical method for improving the heat aging resistance and hot strength of resin compositions containing MX nylon is not yet known.

[Interrib points to be solved by the present invention] The purpose of the present invention is to improve the problems of the prior art and to obtain an excellent heat-resistant polyamide resin composition that has both hot strength and heat aging resistance. .

"Means for Solving the Problem" As a result of our research, the present inventors found that when MX-J iron is blended with a powdered thermosetting resin such as a phenolic resin having a specific particle size and glass fiber, We have discovered a method that can yield a polyamide resin composition with excellent hot strength (!: heat resistance), and have arrived at the present invention.

That is, the invention provides poly(γ) amide resins 20 to 9 obtained from xylylene diamine and α,ω-direct aliphatic dibasic acid.
For 100 parts by weight of a polyamide resin mixture consisting of 9 parts by weight and 1 part by weight of nylon 6680-1, particles having a particle size of 1 to 8
A molding IJ made by blending 5 to 85 parts by weight of a powdered thermosetting resin with a diameter of 0.00 μm and 5=300 parts by weight of glass fiber.
7 This invention relates to a mido resin composition.

The MX nylon used in the present invention is composed of metaxylylene diamine alone or a diamine mixture of 60% or more metaxylylene diamine and 40% or less free xylylene diamine, and the general formula HOOC(CH2)YC00H (ri is 6 α,ω-linear aliphatic dibasic acids having 6 to 18 carbon atoms represented by - It is a polyamide resin synthesized by -1 through a polycondensation reaction with icosanedioic acid, etc.

Considering the balance of moldability, molding properties, etc. of the molded product obtained from the resin composition of the present invention, adipic acid and sebacic acid are particularly suitable as the α,ω-straight aliphatic dibasic acid.

Nylon 66 used in the present invention makes it possible to significantly shorten the moldability of MX nylon, that is, the molding cycle time, and its blending ratio is polyamide resin 20-9.
The amount of nylon is 661 to 80 parts by weight, preferably 5 to 75 parts by weight, per 9 heavy electric.

If the blending ratio of nylon 66 to 99 parts by weight of MX nylon is less than 1 part by weight, the effect on improving the moldability of MX nylon will be small;
If more than 6,680 parts by weight of nylon is blended, characteristics such as mechanical strength and rigidity will be impaired.

Examples of thermosetting resins used in the present invention include, but are not limited to, phenol resins, xylene resins, melamine resins, epoxy resins, unsaturated polyester resins, urea resins, furan resins, and alkyd resins. .

Among these thermosetting resins, phenol resins, xylene resins, melamine resins, and epoxy resins are preferred, and among these, phenol resins and xylene resins are particularly preferred. As the phenol resin, one containing a methylol group is preferable, and in this case, a fugnol resin containing 0.5 to 1 Qwt% of a methylITJ-l group is preferable.

The particle size of the thermosetting resin used in the present invention is 1 to 800.
μrn, preferably 1 to 100 μtn, particularly preferably 5 to 50 μm.

When the particle size of the thermosetting resin is 800 μm or more, moldability decreases.

The blending ratio of the thermosetting resin used in the present invention is 5 to 85 parts by weight, preferably 10 to 50 parts by weight, based on 100 parts by weight of the polyamide resin mixture.

If the thermosetting resin is less than 5 parts by weight per 100 parts by weight of the polyamide resin mixture, the improvement in hot strength and heat aging resistance will be negligible, while if the thermosetting resin is 85 parts by weight or more, the mechanical strength and moldability will be significantly improved. This is not desirable as it spoils the appearance.

The blending ratio of glass fiber used in the present invention is 5 to 5 parts by weight per 100 parts by weight of the polyamide resin mixture in the present invention.
The amount is 300 parts by weight, preferably 10 to 250 parts by weight.

If the blending ratio of glass iJ1 fibers is less than 5 parts by weight with respect to 10 weight parts of the polyamide resin mixture in the present invention, the effect of improving mechanical strength, thermal properties, etc. will not be sufficient; If the amount is more than 1 part by weight, moldability, warpage characteristics, and surface smoothness are impaired, which is not preferable.

The polyamide resin composition of the present invention is generally melt-kneaded in an extruder at a temperature 5 to 50 t' higher than the melting point of the polyamide resin, and then mixed with pellets. Manufactured by

The composition of the present invention contains one or more commonly used additives, such as stabilizers against aging due to oxidation, heat, and ultraviolet rays, inhibitors, nucleating agents, plasticizers, mold release agents, flame retardants, Contains antistatic agents, lubricants, etc. 1. can be used.

Moreover, without impairing the purpose of the present invention, commonly used inorganic fillers such as calcium carbonate, talc, and wollastonite, whiskers such as potassium titanate and silicon carbide, carbon fibers, alumina/silica ceramic fibers, etc. may be blended. You can also use

[Action and effect of the invention]

The polyamide resin composition of the present invention has excellent performance in hot strength and heat aging resistance, and is useful for automobile engine covers, xylencers, connectors, and other applications that require heat resistance. .

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to Examples and Comparative Examples.

The mechanical properties were determined by the following test method.

Tensile m degree: ASTM D638 Tensile elongation +ASTM 0638 Tensile modulus: ASTM 0638 Bending strength: ASTM D790 Flexural modulus: ASTM D790 Example 1 Poly(methaxylylene adipamide) manufactured by Mitsubishi Gas Chemical ■
pellet (1 g of polymer dissolved in 100 ml of 98% sulfuric acid, measured at 25°C, and the relative viscosity (hereinafter referred to as "relative viscosity")
100 parts by weight of nylon 66 (relative viscosity: 2.25) 2
5 parts by weight, particulate phenolic resin (manufactured by Kanebo, product name:
Belval (registered trademark) R-800 (primary particle size 1~
20 μm)) and 70 parts by weight of chopped glass fiber strands having a length of 3 nm were added, mixed in a tumbler, melted and kneaded at 280°C using a vented extruder, and then extruded into a string. After cooling in a water bath, it was cut and dried to produce a pellet-shaped molding material.

Next, this molding material was injection molded at a mold temperature of 130°C.
A molded product C was obtained.

Table 1 shows the heat aging resistance test results of the molded products, and Table 2 shows the hot strength test results.

Example 2 Example 1 except that the blending amount of nylon 66 was 38 parts by weight, the particulate phenol resin was 51 parts by weight, and the chopped glass fiber strand was 189 parts by weight.
A pellet-shaped molding material was produced by blending and melt-kneading in the same manner as above.

Next, it was molded in the same manner as in Example 1 to obtain a molded product. Table 1 shows the heat aging resistance test results of the molded products, and Table 2 shows the hot strength test results.

Comparative Example 1 Example 1 except that particulate phenolic resin was not blended.
A pellet-shaped molding material was obtained in the same manner as above.

Next, this molding material was grown in the same manner as in Example 1 to obtain a molded product.

The evaluation results of this molded product are shown in Tables 1 and 2.

Comparative Example 2 Example 2 except that particulate phenolic resin was not blended.
A pellet-shaped molding material was obtained in the same manner as above.

Next, this molding material was molded in the same manner as in Example 1 to obtain a molded product.

The evaluation results of this molded product are shown in Tables 1 and 2.

Comparative Example 3 Nylon 6 pellet (relative viscosity 82.30) 1
00 parts by weight, 40 parts by weight of particulate phenolic resin (same as used in Example 1), glass fiber (length: 3
rnm chopped strand) was added, mixed in a tumbler, and heated at 260°C using a vented extruder.
After melt-kneading, the mixture was extruded into a string shape, cooled in a water bath, cut, and dry-burned to produce a pellet-shaped molding material.

Next, this molding material was injection molded at a mold temperature of 80° C. to obtain a molded product.

The evaluation results of the molded products are shown in Tables 1 and 2.

Table 1 The comparison value was taken as the retention rate.

Table 2 Patent applicant: Mitsubishi Gas Chemical Co., Ltd. Agent: Patent Attorney Sadafumi Kohori

Claims (1)

[Claims] (1) Particle size for 100 parts by weight of a polyamide resin mixture consisting of 20 to 99 parts by weight of a polyamide resin obtained from xylylene diamine and an α,ω-linear aliphatic dibasic acid and 6680 to 1 part by weight of nylon. 5 to 85 parts by weight of a powdered thermosetting resin with a diameter of 1 to 800 μm and 5 to 30 parts of glass fiber
0 parts by weight of a polyamide resin composition for molding.