JPH02120359A - Resin composition for connectors - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Object of the invention] (Industrial application field) The present invention provides a molded product having excellent rigidity and impact resistance,
Furthermore, the present invention relates to a resin composition for connectors in which the rigidity does not decrease even when water is absorbed.

(Prior Art) Polyamide is generally used as a material for connectors because of its excellent heat resistance, toughness, and electrical properties.

However, polyamide has drawbacks such as a decrease in rigidity and a decrease in dimensional stability when it absorbs water, and is not fully satisfactory as a material for connectors.

It is known to blend modified polypropylene with low water absorption to improve the water absorption of polyamide (see, for example, Japanese Patent Publication No. 55-2050'0).
In the case of this technology, new problems arise such as warping due to the difference in crystallization rate between polyamide and polypropylene, and a decrease in heat resistance and flame retardance.

(Problems to be Solved by the Invention) As mentioned above, connectors manufactured from conventional polyamide resins or resin compositions containing the same have problems such as a decrease in rigidity due to water absorption, a problem with warpage during molding, and has the problem of reduced heat resistance and flame retardancy.

Accordingly, the present invention provides a resin composition for connectors, which provides molded products with excellent rigidity, impact resistance, appearance, and flame retardancy, and which does not lose its rigidity even at high temperatures or when water is absorbed. The purpose is to

[Structure of the Invention] (Means and Effects for Solving the Problems) The resin composition for connectors of the present invention has (A) a relative viscosity n1 of 0.5.
It is characterized by containing 60 to 80% by weight of a polyamide resin having a molecular weight of 3.3 to 3.3% and 40 to 20% by weight of (B) a modified polyphenylene ether resin.

Component 1, A) constituting the resin composition for connectors of the present invention is a polyamide resin.

The polyamide resin used in the present invention includes polylactams such as nylon 6, nylon 11, and nylon 12, polyamides obtained from dicarboxylic acids and diamines such as nylon 66, nylon 6/10, and nylon 6/12, nylon 6/66, Nylon 6/6/12, nylon 6/66
/6/10, nylon 6/66/12, nylon 6/6
Examples include copolymerized polyamides such as T (T is a terephthalic acid component), polyetheramides or polyesteretheramides, and mixtures of two or more thereof. Among these, nylon 6 or nylon 66 is preferred because it has a high melting point and excellent rigidity.

The molecular weight of the polyamide resin is not particularly limited, but the relative viscosity n, (98 according to JIS K6810)
% (measured in sulfuric acid) should be between 2.30 and 3.20.

Although the terminal group concentration of the polyamide resin is not particularly limited, it is preferably a concentration that does not significantly reduce moldability.

Component (B) used in the present invention is a modified polyphenylene ether resin.

This modified polyphenylene ether resin is obtained by graft polymerizing a modifier such as an unsaturated carboxylic acid or a derivative thereof or an unsaturated imide compound to a polyphenylene ether resin.

Polyphenylene ether resin is US patent cylinder 3.30
Specification No. 6.874, Specification No. 3.306°875, Specification No. 3,257.357, and Specification No. 3.25
It can be produced by the method described in No. 7.358, and is a polymer consisting of repeating units represented by the following general formula.

(R', R'', R' and R4 represent the same or different residues such as hydrogen, halogen, alkyl group, aryl group, and n represents the degree of polymerization) As polyphenylene ether resin, poly(2, 6
-dimethylphenylene-1,4-ether), poly(2
, 6-dimethylphenylene-1,4-ether), poly(2,6-dipromophenylene-1,4-ether),
Poly(2-methyl-6-ethylphenylene-1,4-ether), poly(2-chloro-6-methylphenylene-
1,4-ether), poly(2-methyl-6-itubrobylphenylene-1,4-ether), poly(2,6-
di-n-propylphenylene-1,4-ether), poly(2-chloro-6-propylphenylene-1,4-ether), poly(2-chloro-6-ethylphenylene-1)
,4-ether), poly(2-methylphenylene-1,
4-ether), poly(2-chlorophenylene-1゜4
-ether), poly(2-methyl-6-phenylphenylene-1,4-ether), poly(2-bromo-6-phenylphenylene-1,4-ether), poly(2,4
°-methylphenylphenylene-1,4-ether),
Examples include poly(2,3,6-drimethylphenylene-1,4-ether), copolymers thereof, and copolymers obtained by graft polymerizing a styrene compound thereto.

Examples of unsaturated carboxylic acids or derivatives thereof used as modifiers include monocarboxylic acids such as acrylic acid and methacrylic acid, dicarboxylic acids such as maleic acid, itaconic acid, and fumaric acid, and anhydrides thereof. Among these, the dicarboxylic acids or their anhydrides are preferred, and maleic anhydride is particularly preferred.

Examples of the unsaturated imide compound used as a modifier include maleimide, N-methylmaleimide, N-ethylmaleimide, N-propylmaleimide, N-butylmaleimide, N-
-Octylmaleimide, N-phenylmaleimide, N-
(0-methylphenyl)maleimide, N-(m-methylphenyl)maleimide, N-(p-methylphenyl)
maleimide, N-(methoxyphenyl)maleimide, N
-(Chlorphenyl)maleimide, N-(carboxyphenyl)maleimide, N-benzylmaleimide, N-naphthylmaleimide, N-cyclohexylmaleimide, itaconimide, N-methylitaconimide, N-phenylitaconimide, etc. Can be done. Among these, N-cyclohexylmaleimide, N-benzylmaleimide, N-phenylmaleimide, and N-(carboxyphenyl)maleimide are preferred.

One type of these unsaturated carboxylic acids or derivatives thereof or unsaturated imide compounds can be used, or two types can be used.
More than one type can be used.

The amount of the modifier such as unsaturated carboxylic acid used to modify the polyphenylene ether resin is preferably 0.05% by weight or more based on the polyphenylene ether resin,
More preferably, the amount used is 0.1 to 5% by weight.
．． If the amount is less than 0.5% by weight, the compatibility between the polyamide resin and the polyphenylene ether resin will decrease, and the toughness such as tensile strength and Izot impact strength of the molded article will decrease, which is not preferable.

The modified polyphenylene ether resin can be produced by a method of melting and heating a polyphenylene ether resin, an unsaturated carboxylic acid, etc. at a temperature of 250 to 350° C. in the presence of a peroxide.

Examples of the peroxide used in this case include benzoyl peroxide, α, α-bis-t-butylperoxy-p-diisopropylbenzene, and the like.

The content of components (A) and (B) is from 60 to 60%.
80% by weight, and component (B) is 40 to 20% by weight. If the content of component (A) is less than 60% by weight, the moldability of the composition will decrease, and if it exceeds 80% by weight, the rigidity and dimensional stability will decrease due to water absorption.

The blending amounts of component (A) and component (B) are preferably 65 to 75% by weight for component (A) and 35 to 25% by weight for component (B).
Weight%.

In addition to the above-mentioned components (A) and (B), a release agent may be further blended into the resin composition for connectors of the present invention.

As the mold release agent used in the present invention, one or more types selected from polyalkylene glycols and terminal derivatives thereof, stearic acid metal salts, higher fatty acid bisamide compounds, and higher aliphatic alcohols can be used.

Examples of polyalkylene glycols and terminal derivatives thereof include polyethylene glycol, polypropylene glycol, laurylphenoxypolyethylene glycol, stearylphenoxypolyethylene glycol, polyethylene glycol diamine, polypropylene glycol diamine, methoxypolyethylene glycol, and the like.

Examples of the metal stearate include aluminum stearate, zinc stearate, tin stearate, cadmium stearate, calcium stearate, magnesium stearate, barium stearate, and lithium stearate.

As a higher fatty acid bisamide compound, ethylene bis(
Examples include stearylamide), methylene bis(stearylamide), and distearyladipamide.

Examples of higher aliphatic alcohols include lauryl alcohol,
Examples include myristyl alcohol, cetyl alcohol, stearyl alcohol, aracyl alcohol, and behenyl alcohol.

The content of the mold release agent is the total amount of the polyamide resin as the component (A) and the polyphenylene ether resin as the component (B).
0.05 to 10 parts by weight, preferably 0 parts by weight
．． It is 1 to 1 part by weight. If the content of the mold release agent is less than 0.05 parts by weight, the cooling time during injection molding will take too long, and even if the content exceeds 10 parts by weight, the cooling time during injection molding will no longer be shortened. On the contrary, the mechanical properties of the molded product deteriorate.

A dye, a pigment, a heat resistance imparting agent, and a flame retardant can be added to the resin composition for a connector of the present invention, if necessary.

The method for producing the resin composition for connectors of the present invention is not particularly limited, and can be produced, for example, by the following method.

A modified polyphenylene ether resin (or a modified polyphenylene ether resin 4 resin and a mold release agent) is added to the polyamide which is still in a molten state after the completion of the polymerization reaction.
Method of melt-kneading at 50°C, preferably 250 to 320°C: Method of tri-blending modified polyphenylene ether resin (or modified polyphenylene ether resin and mold release agent) with powdered or pelleted polyamide: Polyamide and modified polyphenylene ether resin A method such as a method of melt-kneading (or a modified polyphenylene ether resin and a mold release agent) using an extruder can be applied.

The resin composition for connectors of the present invention can be used as a manufacturing material for various electrical components, such as connectors, junction blocks, fuse boxes, and relay boxes.

(Example) Examples and comparative examples are shown below. Note that parts represent parts by weight.

Example 1 Polyamide 66 having a relative viscosity of 2.50 was produced by melt polymerizing substantially equimolar salts of hexamethylene diamine and adipic acid.

Next, 0.4 parts of polyphenylene ether resin having an intrinsic viscosity of 0.49 (25°C, in chloroform) was used.
5 parts of maleic anhydride and 2 parts for this maleic anhydride.
30 parts of benzoyl peroxide using an extruder
A modified polyolefin resin was produced by kneading at 0°C.

Thereafter, 70 parts of the polyamide resin and 30 parts of modified polyphenylene ether resin were mixed into a screw with a screw diameter of 30 mm.
A pellet of the resin composition for connectors of the present invention was obtained by melt-kneading at 280° C. using an extruder.

Using the pellet of the composition thus obtained, the properties of the injection molded article were measured. The molding conditions and measurement method are shown below. The results are shown in Table 1.

Injection molding machine: Toshiba Machine 15-80 cylinder - Set temperature: C + 260°C: C.

280°C: C, 280°CTC, (nozzle part) 280°C Injection pressure 600 kg / cm 2 mold parts / 80°C Injection time: 10 seconds Cooling time = 20 seconds At below ■～ ■ and ■ are tests in an absolutely dry state, and ■ and ■ are tests after water absorption.

■Tensile strength: ASTM D-638 ■Bending modulus:
ASTM D-790 ■Izotsu impact strength: AST
M D-256 ■Heat distortion temperature: ASTM D-64
8 (Load: 4.6 kg/Cm'') ■Moldability: The resin composition of the present invention was molded under the following molding conditions, and the flow length was measured.

(Molding conditions) Schilling temperature: C, 260°C: C2290'C;
Ca290°C: C4 (nozzle part) 290°C, injection pressure 800kg/cm" Mold temperature: 80°C Injection time = 10 seconds Cooling time: 20 seconds ■Flammability: Evaluated by UL vertical combustion test.

■Water absorption rate: The following formula when immersed in water at 23°C for 24 hours: Water absorption rate (%) = Water absorption rate was determined from the weight of the test piece before immersion.

■ Retention rate of bending elastic modulus: The bending elastic modulus after water absorption under the conditions of (■) above was determined in the same manner as ((2) above), and the following formula and the components shown in Table 1 were used in the same manner as in Example 1. A pellet of the resin composition and a pellet for comparison were manufactured. Using this pellet, each characteristic was measured in the same manner as in Example 1. The results are shown in Table 1.

I asked for it from.

■Appearance was evaluated by second visual inspection.

Examples 2 to 4 and Comparative Examples 1 to 5 Example 5 0.15 parts of methoxypolyethylene glycol was further added to 100 parts of the resin composition produced in Example 2,
The mixture was mixed for 30 minutes to obtain pellets of the resin composition for connectors of the present invention.

The pellets of the obtained resin composition were dried under vacuum at 80° C. for 48 hours, and then the releasability from the mold when injection molded was measured. The injection molding conditions and the method for measuring mold releasability are as follows. The results are shown in Table 2.

Warm birch bean injection molding machine: Toshiba Machine IS-75P N I
I cylinder setting temperature: C, 260℃; C2270℃:
C, 280℃: C4 (nozzle part) 280℃ Injection pressure 650kg/cm" Mold temperature: Moving mold 80℃ Fixed mold 80℃ Injection time: 10 seconds Cooling time: 12 seconds The mold properties were measured using a mold and an injection molding machine equipped with a mold release force measurement device as shown in the figure.In the figure, 1 is the cylinder of the injection molding machine, 2 is the molded product, 3 is the fixed mold, and 4 is the injection molding machine. 2 Zect turbines, 5 is a core, 6 is a movable mold, 7 is an ejector plate, 8 is a pressure sensor, 9 is a pressure sensor fixing plate, 10 is a knockout rod, and 11 is a recorder.Fixed mold 3 and movable mold Type 6 is 80mm wide and 100mm long.
It is processed to form a mold with a depth of 30 mm and a wall thickness of 2 mm, with cross-shaped ribs inside.

To measure the mold releasability, after injecting the resin composition under the above conditions, the movable mold 6 is first moved backward, then the knockout rod 10 is pressed against the pressure sensor 8, and the molding is performed via the ejector plate 7 and the ejector turbine 4. The force (release force) applied to the pressure sensor 8 when the product 2 was released from the core 5 was measured using a recorder.

Examples 6 to 12 and Comparative Example 6.7 A resin composition for a connector of the present invention was obtained in the same manner as in Example 6 using each component shown in Table 2.

The mold release force was measured in the same manner as in Example 6 using the obtained composition. The results are shown in Table 2.

Various properties were equivalent to those of Example 2 shown in Table 1.

[Effects of the Invention] The resin composition for connectors of the present invention has excellent moldability, and its molded products have excellent rigidity, impact resistance, appearance, and flame retardance. Furthermore, the molded article maintains excellent rigidity even under high temperatures and when water is absorbed.

[Brief explanation of the drawing]

The figure is a schematic diagram of a mold and an injection molding machine equipped with a mold release force measuring device. Teitemari - 11Fft official book (method) % formula % 1. Indication of the case 1988 Patent Application No. 270973 2. Name of the invention Resin composition for connectors 3. Person making the amendment Relationship to the case Patent applicant name Title +0201 Ube Industries Co., Ltd. 4. Date of agent's amendment order: March 7, 1999 (shipping port) 6. Brief explanation column of drawings in the specification subject to amendment and drawing No. 1

Claims (2)

[Claims] (1) For a connector characterized by containing (A) 60 to 80% by weight of a polyamide resin having a relative viscosity η_r of 0.5 to 3.3 and (B) 40 to 20% by weight of a modified polyphenylene ether resin. Resin composition. (2) A resin composition for connectors, which contains 0.05 to 10 parts by weight of a mold release agent based on 100 parts by weight of the total amount of components (A) and (B) according to claim 1.