JPH07207151A - Resin composition for connectors - Google Patents

Abstract

(57) [Summary] [Structure] (a) Polyamide resin containing aromatic ring: 55-
84 wt% (b) Modified polyolefin resin 35 to 15 wt% (c) Crystallinity 0 to 20%, ethylene content 70 to 95
Resin composition for connectors, wherein (d) 0 to 100 parts by weight of the inorganic reinforcing material is blended with 100 parts by weight of a mixture consisting of 10 to 1% by weight of a modified ethylene / α-olefin random copolymer of mol%. [Effect] The resin composition for a connector of the present invention has heat resistance,
It has excellent rigidity during water absorption, toughness, dimensional stability, and anti-freezing properties on roads, and is suitable as a molding material for connectors.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition for a connector which is excellent in heat resistance, rigidity upon absorption of water, toughness, dimensional stability, resistance to road anti-icing agent and the like.

[0002]

2. Description of the Related Art Polyamide resin has excellent heat resistance, oil resistance, moldability, rigidity, toughness, etc., so that it is particularly useful for interior and exterior parts of automobiles such as cooling fans and radiator tanks. Top and base,
It has been applied to various functional parts such as heater core tanks, cylinder head covers, canisters, gears, connectors, valves, oil tanks, brake piping, fuel tanks, fuel piping tubes, and exhaust gas system parts, or is being developed.

Recently, there has been an increasing demand for these parts to be lighter in weight and more highly functional, and therefore, shortening and thinning of resin parts have been positively studied, and automobile connectors are no exception. However, polyamide resin absorbs water more easily than other resins, and water absorption lowers the material rigidity or heat resistance, which greatly hinders the miniaturization, thinning, and high functionality of resin parts. It is the actual situation.

As a method of lowering the water absorption of polyamide resin and improving the dimensional stability and anti-freezing property of roads, an attempt has been made to blend a lower polyamide such as nylon 6 or nylon 66 with a higher polyamide such as nylon 11 or nylon 12. Although it has been done (JP-A-57-212252).
JP-A-57-80448, JP-A-57-
No. 80449), it was insufficient to maintain the heat resistance inherent to polyamide resins.

On the other hand, attempts have been made to reduce water absorption by mixing a polyamide resin with a polymer other than the polyamide resin (Japanese Patent Laid-Open Nos. 3-285951 and 4-202560).

[0006]

However, if a lower polyamide resin such as nylon 6 or nylon 66 is mixed with, for example, a polyolefin resin, a certain effect of lowering the water absorption can be obtained, but a polyolefin resin is simply mixed. If it is used alone, the heat resistance is lowered, or it is insufficient to obtain rigidity and dimensional stability when absorbing water. Moreover, by mixing the olefin resin, the toughness and impact resistance of nylon are impaired, and especially thinning, dimensional stability,
It is not possible to satisfy the required functions of resin molded products that require heat resistance and toughness.

Particularly in recent automobile parts, there is an increasing demand for lighter, thinner, shorter, smaller and thinner parts, and accordingly, especially connector parts in an engine muller have higher heat resistance,
Rigidity, toughness, and dimensional stability at the time of water absorption are required, and it has been an object to provide a resin composition capable of obtaining a connector molded product having these properties well balanced.

[0008]

In order to solve the above problems, the present invention takes the following means. That is, the resin composition for a connector of the present invention comprises (a) a polyamide resin containing an aromatic ring in a molecular constitution unit:
55-84% by weight (b) One modified polyolefin resin selected from a modified polypropylene resin modified with a graft monomer selected from an unsaturated carboxylic acid, an acid anhydride thereof or a derivative thereof, or a modified polyethylene resin 35-
15% by weight (c) Modified with a grafting monomer selected from unsaturated carboxylic acid, its acid anhydride or its derivative, and has a crystallinity of 0 to 20% by X-ray and an ethylene content of 70 to 95.
A resin composition for connectors, which comprises (d) 0 to 100 parts by weight of an inorganic reinforcing material based on 100 parts by weight of a mixture consisting of 10 to 1% by weight of a modified ethylene / α-olefin random copolymer of 10% by weight. It is a feature.

In the present invention, the polyamide having an aromatic ring as a molecular constitutional unit is a polyamide obtained by copolymerizing an aromatic compound such as terephthalic acid or isophthalic acid, preferably nylon 6T (T is an abbreviation for terephthalic acid). , Nylon 66 / 6T, nylon 6T / 6, nylon 6I (I is an abbreviation for isophthalic acid), nylon 66 / 6I, nylon 6I
/ 6, etc., and nylon 66 / 6T is more preferable.

Although the component composition ratio of the aromatic ring-containing polyamide used in the present invention is not particularly limited, the melting point of the polyamide determined by the component composition ratio is 270 to 320 ° C.
Is preferable, and 280 to 310 ° C. is more preferable.
Further, in the case of nylon 66 / 6T, the melting point determined by the component composition ratio thereof is preferably in the range of 270 to 300 ° C,
More preferably, it is 280 to 300 ° C.

The degree of polymerization of the aromatic ring-containing polyamide resin is not particularly limited, but in terms of moldability, the relative viscosity (ηr) measured with 98% sulfuric acid is in the range of 2.0 to 3.5. Some are preferred. The modified polypropylene resin or modified polyethylene resin as the component (b) used in the present invention, or the unmodified polyolefin resin before preparation is not particularly limited, and commercially available polypropylene resin or polyethylene resin can be used. Preferably the density is 0.89
~ 0.93 g / cm ³ , melt flow rate (ASTM
D1238) is a polypropylene resin of 0.01 to 50 g / 10 min.

Representative examples of the grafting monomers selected from unsaturated carboxylic acids, their acid anhydrides or their derivatives used as modifiers include acrylic acid, maleic acid, fumaric acid, tetrahydrophthalic acid, itaconic acid,
Unsaturated carboxylic acids such as nadic acid R, or acid anhydrides or derivatives thereof, such as maleimide, maleic anhydride, monomethyl maleate, and dimethyl maleate are exemplified. Among these, unsaturated dicarboxylic acids and their acid anhydrides are preferable, and maleic acid, nadic acid R or their acid anhydrides are particularly preferable.

The modified ethylene / α-olefin random copolymer used as the component (c) in the present invention has an X-ray crystallinity of 0 to 20%, preferably 0 to 15%.
And the ethylene content is 70 to 95 mol%, preferably 70 to 85 mol%, and the α-olefin component constituting the modified ethylene / α-olefin random copolymer has α of about 3 to 18 carbon atoms. -Is an olefin,
Propylene, 1-butene, 1-hexene, 4-methyl-
Examples thereof include 1-pentene and 1-decene, and propylene is particularly preferable.

If the modified ethylene / α-olefin random copolymer used in the present invention has a crystallinity of more than 20% or an ethylene content of more than 95 mol%, the toughness is lowered and the resulting connector molding is obtained. The product does not have sufficient toughness for practical use. On the other hand, when the content of ethylene is less than 70 mol%, the heat resistance is lowered, and the heat resistance rigidity and the water absorption rigidity of the obtained connector molded product are lowered.

Examples of the inorganic reinforcing material that can be used in the present invention include glass fiber, asbestos fiber, carbon fiber, wollastonite, talc, calcium carbonate, alumina, mica, spherical glass, potassium whisker titanate, kaolin, clay and the like. Can be mentioned. Also, various combinations of these reinforcing materials may be used. The resin composition for a connector of the present invention comprises 55 to 84% by weight of component (a) polyamide, preferably 65 to 79% by weight, and 35 to 15% by weight of component (b) modified polyolefin resin, preferably 30%.
˜20% by weight and (c) component-modified ethylene / α-olefin copolymer 10 to 1% by weight, preferably 5 to 1% by weight
100 parts by weight of the mixture consisting of 0 to 100 parts by weight of the inorganic reinforcing material (d).

If the content of the component (a) polyamide in all the polymers, that is, the polyamide containing an aromatic ring, is less than 55% by weight, the heat resistance is lowered, which is not preferable. On the other hand, if it exceeds 84% by weight, the water absorbency of the composition increases and the rigidity upon water absorption decreases, which is not preferable. When the content of the component (b) modified polyolefin resin, that is, the modified polypropylene resin or modified polyethylene resin in all polymers is less than 15% by weight, the road anti-icing resistance is lowered, and the water absorption is increased and the rigidity at the time of water absorption is decreased. It is not preferable.

On the other hand, when the amount of the modified polyolefin resin as the component (b) exceeds 35% by weight, the moldability is deteriorated, so that the appearance of the obtained connector molded product is deteriorated and the heat resistance is markedly decreased. Not practical. The component (c) -modified ethylene / α-olefin copolymer in all polymers is an essential component for imparting toughness and impact resistance. When the amount of the modified ethylene / α-olefin copolymer is less than 1% by weight, the toughness, especially the impact resistance is deteriorated. On the other hand, when the amount of the modified ethylene / α-olefin copolymer is more than 10% by weight, molding is performed. Practicality, heat resistance, and rigidity deteriorate, so it cannot be used practically.

The inorganic reinforcing material has a higher toughness, heat resistance,
Used as a mixture when imparting rigidity and impact resistance. However, the amount of inorganic reinforcement used is 10
If it exceeds 100 parts by weight relative to 0 parts by weight, moldability and appearance are deteriorated, and toughness is rather deteriorated, resulting in brittleness.
It is not preferable because the function as a connector molded product is impaired.

The mixing method of the polyamide, the modified polyolefin, the modified ethylene / α-olefin copolymer and the inorganic reinforcing material added as necessary is not particularly limited, and a commonly known method can be adopted. Further, the modification method of the polyolefin resin such as polypropylene resin or polyethylene resin, or the graft monomer selected from unsaturated carboxylic acid of ethylene / α-olefin copolymer or its derivative is not particularly limited, and the polyolefin resin or the ethylene / α-olefin may be modified in advance. The copolymer and the modified graft monomer are simultaneously supplied to the extruder, and the modified polyolefin resin or modified ethylene / α-olefin copolymer modified by kneading may be kneaded with the polyamide and the inorganic reinforcing material, Alternatively, a polyamide, an ethylene / α-olefin copolymer, and a graft monomer, which have been kneaded in advance with an extruder, and a modified polyolefin resin may be kneaded, or a graft monomer and a polyamide which are modifiers. Polyolefin resins, ethylene · alpha-olefin copolymer and inorganic reinforcements were simultaneously fed into the extruder, may be kneaded.

The kneading method is not particularly limited as long as the characteristic function of the obtained resin composition is not impaired. Further, other components such as pigments, dyes, heat-resistant agents, antioxidants, weathering agents, lubricants, crystal nucleating agents, etc. are added to the polyamide resin composition for connectors of the present invention as long as the moldability and physical properties are not impaired. Can be introduced.

Further, other resin such as polyamide, polyester, polyolefin, polyphenylene oxide and polyphenylene sulfide can be blended in the resin composition for a connector of the present invention depending on the purpose. In particular,
It is industrially useful to make several compositions having different melting points by blending one composition of the present invention with an aliphatic polyamide such as nylon 6 or nylon 66 in small amounts.

The connector in the present invention means a male / female connector for connecting various electric wires, but is preferably a connector for an automobile, more preferably a connector for a wire harness of an automobile.

[0023]

EXAMPLES The present invention will be described in detail below with reference to examples. The physical properties of the test pieces shown in Examples and Comparative Examples were measured and evaluated by the methods described below. The obtained test piece is heated to a temperature of 3
After processing for 100 hrs. In an atmosphere of 5 ° C. and a humidity of 95% RH, the elastic modulus when absorbing water was measured. The road antifreeze resistance was evaluated using the following connector molded product. (1) Tensile properties: ASTM D638 (2) Bending properties: ASTM D790 (3) Izod impact strength: ASTM D256 (4) Heat distortion temperature: ASTM D648 (5) Road antifreeze resistance: Maximum width 55 mm, height 13m
Connector molded product 1 with m, depth of 37 mm, and thickness of 1 mm as shown in FIG. 1 was treated with hot water at 80 ° C. for 24 hrs, and then a 5% calcium chloride aqueous solution was applied to the entire surface of the molded product.
Left for 1 hr in a gear oven at -30 ° C, then for 1 hr in an atmosphere of -30 ° C, then left at room temperature for 30 minutes, and then evaluated as one cycle of cold heat treatment / calcium chloride coating treatment in which a 5% calcium chloride aqueous solution is entirely coated. Then, the number of cycles until cracks that could be observed with the naked eye were generated on the surface of the connector molded article 1 was measured. Example 1 To 100 parts by weight of a polypropylene resin having a melt flow rate (MFR) of 0.5 g / 10 min was added 0.6 part of a mixture of maleic anhydride and a peroxide, and the mixture was uniformly mixed with a stirrer to obtain a pipe having a diameter of 45 mm. A modified polypropylene was obtained by melt-kneading with a twin-screw type extruder.

25% by weight of the modified polypropylene pellets obtained here was mixed with nylon 66/6 having a relative viscosity of 2.55.
73% by weight of T (66 / 6T = 62/38% by weight) copolymer, and 2% of crystallinity and 75 mol% of ethylene content
2% by weight of a mixture of ethylene and propylene copolymer 10
A mixture of maleic anhydride and a peroxide was added to 0 part by weight.
After uniformly mixing 3 parts by weight, the mixture was melt-kneaded and pelletized with a twin-screw extruder having a diameter of 45 mm.

The pellets obtained here were vacuum dried at 80 ° C., and then the temperature of the cylinder was 300 ° C. by an injection molding machine.
The ASTM test piece and the connector molded article of FIG. 1 were molded under a mold temperature of 100 ° C. The measurement results of the physical properties of the obtained test piece at the time of absolute dryness and at the time of water absorption are as follows, and it was found that the composition had well-balanced toughness, heat resistance and rigidity.

Tensile strength: 60 MPa Izod impact strength: 110 J / m Heat distortion temperature: 185 ° C. Bending elastic modulus (during water absorption): 1400 MPa When the connector molded product was subjected to the above-mentioned calcium chloride cycle test, it was 50 It was confirmed that the surface of the molded product did not crack at all even after the cycle was exceeded, and that the connector had excellent road freezing resistance. Comparative Example 1 25% by weight of the modified polypropylene resin used in Example 1,
Nylon 66 / 6T with relative viscosity of 2.55 (66 / 6T =
62/38 wt% ratio) 60 wt% copolymer, crystallinity 2
%, 100 parts by weight of a mixture of 15% by weight of an ethylene / propylene copolymer having an ethylene content of 75 mol% and 0.3 part by weight of a mixture of maleic anhydride and a peroxide were homogeneously mixed, and Melt kneading and pelletizing were carried out by the same method.

After the pellets were vacuum dried in the same manner as in Example 1, ASTM test pieces were molded. However, since the amount of the component (c) was too large, the molding fluidity was poor, and thus the appearance gloss of the test pieces was lowered. The results of measuring the physical properties of the obtained test piece during absolute drying and water absorption are as follows, and although it has excellent impact resistance, it is inferior in heat resistance and elastic modulus during water absorption, and has a property balance as a resin composition for connectors. Proved to be inferior to.

Tensile strength: 45 MPa Izod impact strength: 205 J / m Heat distortion temperature: 95 ° C. Bending elastic modulus (at the time of water absorption): 850 MPa When a connector is molded with this composition, flow marks and welds are formed due to poor molding fluidity. It was found that it cannot be used as a conspicuous connector product. Example 2 Nylon 66 / 6T (66/6) having a modified polypropylene resin used in Example 1 of 23.5% by weight and a relative viscosity of 2.50
T = 55/45% by weight) 100% by weight of a mixture of 75% by weight of copolymer, 12% of crystallinity and 1.5% by weight of ethylene / propylene copolymer having an ethylene content of 79 mol%,
A uniform mixture of 0.3 parts by weight of a mixture of maleic anhydride and peroxide was melt-kneaded and pelletized by the same method as in Example 1.

The pellets obtained here were vacuum dried in the same manner as in Example 1, and then ASTM test pieces were molded under the same molding conditions. The results of measuring the physical properties of the obtained test piece at the time of absolute drying and at the time of absorbing water are as follows, and it was revealed that the composition had a balance of toughness, heat resistance and rigidity. Tensile strength: 65MPa Izod impact strength: 100J / m Heat distortion temperature: 196 ° C Bending elastic modulus (during water absorption): 1620MPa When the above-mentioned calcium chloride resistance cycle test was performed on the molded connector molded product, it exceeded 50 cycles. However, it was found that the surface of the molded product did not crack at all, and it was a connector molded product having excellent road freeze resistance. Comparative Example 2 35% by weight of the modified polypropylene resin used in Example 2,
Nylon 66 / 6T with relative viscosity 2.50 (66 / 6T =
55/45% by weight) A mixture of 65% by weight of the copolymer was melt-kneaded and pelletized in the same manner as in Example 1.

The pellets obtained here were vacuum dried in the same manner as in Example 1, and then ASTM test pieces were molded under the same molding conditions. However, since the component (c) was not present, the molding fluidity was poor and therefore the test pieces were prepared. The external gloss of The results of measuring the physical properties of the obtained test piece during absolute drying and when absorbing water are as follows, but it was found that the toughness and heat resistance were inferior.

Tensile strength: 50 MPa Izod impact strength: 85 J / m Heat distortion temperature: 110 ° C. Bending elastic modulus (during water absorption): 1000 MPa When a connector molded product was molded, a weld line was conspicuous and therefore could not be used as a product. found. Example 3 20% by weight of the modified polypropylene resin used in Example 1,
Nylon 66 / 6T with relative viscosity 2.65 (66 / 6T =
65/35% by weight) copolymer 79% by weight, crystallinity 1
An example was prepared by uniformly mixing 0.3 part by weight of a mixture of maleic anhydride and peroxide with 100 parts by weight of a mixture of 2% and 1% by weight of an ethylene / propylene copolymer having an ethylene content of 79 mol%. Melt kneading and pelletizing in the same manner as in 1.

The pellets obtained here were vacuum dried in the same manner as in Example 1, and then ASTM test pieces were molded under the same molding conditions. The results of measuring the physical properties of the obtained test piece at the time of absolute drying and at the time of absorbing water are as follows, and it was revealed that the composition had a balance of toughness, heat resistance and rigidity. Tensile strength: 62 MPa Izod impact strength: 94 J / m Heat deformation temperature: 180 ° C. Bending elastic modulus (during water absorption): 1350 MPa Comparative example 3 10% by weight of modified polypropylene resin used in Example 3,
Nylon 66 / 6T with relative viscosity 2.65 (66 / 6T =
65/35% by weight) Mixture 10 of 90% by weight copolymer
0 part by weight was melt-kneaded and pelletized in the same manner as in Example 1.

The pellets obtained here were vacuum dried in the same manner as in Example 1, and then ASTM test pieces were molded under the same molding conditions. The physical property measurement results of the obtained test piece at the time of absolute drying and water absorption are as follows, although the heat resistance is excellent,
It was found that the ratio of the component (a) to the component (b) was poor and the component (c) was not present, so that the impact resistance and the rigidity at the time of water absorption were lowered, resulting in poor physical property balance.

Tensile strength: 70 MPa Izod impact strength: 65 J / m Heat distortion temperature: 196 ° C. Bending elastic modulus (during water absorption): 950 MPa The above-mentioned calcium chloride resistance cycle test was performed on the molded connector product. Where 2
It was revealed that the molded product surface could not be used as a connector product due to cracking on the surface at the 5th cycle. Example 4 25% by weight of the modified polypropylene resin used in Example 1,
Nylon 66 / 6T with relative viscosity of 2.55 (66 / 6T =
55/45% by weight) copolymer 72% by weight, crystallinity 2
%, 100 parts by weight of a mixture of 3% by weight of ethylene / propylene copolymer having an ethylene content of 75 mol%, 0.25 parts by weight of a mixture of maleic anhydride and peroxide, and 45 parts by weight of glass fiber having a fiber diameter of 10μ. A uniform mixture of
Melt kneading and pelletizing were carried out in the same manner as in Example 1.

The pellets obtained here were vacuum dried in the same manner as in Example 1, and then ASTM test pieces were molded under the same molding conditions. The results of measuring the physical properties of the obtained test piece at the time of absolute drying and at the time of absorbing water are as follows, and it was revealed that the composition had a balance of toughness, heat resistance and rigidity. Tensile strength: 135MPa Izod impact strength: 130J / m Heat distortion temperature: 245 ℃ Bending elastic modulus (during water absorption): 4700MPa When molded connector moldings, no flow mark was observed and the calcium chloride resistance When a cycle test was carried out, it was found that a crack was not generated even after 50 cycles of treatment, and the connector product had a good balance. Comparative Example 4 25% by weight of the modified polypropylene resin used in Example 1,
Nylon 66 / 6T with relative viscosity of 2.55 (66 / 6T =
55/45 wt% ratio) 60 wt% copolymer, crystallinity 2
%, 100 parts by weight of a mixture of 15% by weight of an ethylene / propylene copolymer having an ethylene content of 75 mol%, 0.25 parts by weight of a mixture of maleic anhydride and a peroxide, and 45 parts by weight of glass fiber having a fiber diameter of 10μ. What was uniformly mixed was melt-kneaded and pelletized by the same method as in Example 1.

The pellets obtained here were vacuum-dried in the same manner as in Example 1, and then ASTM test pieces were molded under the same molding conditions. However, since the molding fluidity was poor, flow marks were generated on the surface of the test pieces. . The measurement results of the impact strength of the obtained test piece are as follows, but the impact resistance is rather lowered despite the increase in the amount of the ethylene / propylene copolymer added. It is presumed that the glass fiber was shredded during the melt-kneading due to the increase in the amount of the ethylene / propylene copolymer, and the interfacial adhesion between the glass fiber and the ethylene / propylene copolymer was lowered.

Izod impact strength: 85 J / m Example 5 23% by weight of the modified polypropylene resin used in Example 1,
Nylon 66 / 6T with relative viscosity of 2.55 (66 / 6T =
55/45% by weight) copolymer 75% by weight, crystallinity 2
%, 100 parts by weight of a mixture of 2% by weight of an ethylene / propylene copolymer having an ethylene content of 75 mol%, 0.25 parts by weight of a mixture of maleic anhydride and peroxide, and 10 parts by weight of glass fiber having a fiber diameter of 13μ. A uniform mixture of
Melt kneading and pelletizing were carried out in the same manner as in Example 1.

The pellets obtained here were vacuum dried in the same manner as in Example 1, and then ASTM test pieces were molded under the same molding conditions. The results of measuring the physical properties of the obtained test piece at the time of absolute drying and at the time of absorbing water are as follows, and it was revealed that the composition had a balance of toughness, heat resistance and rigidity. Tensile strength: 95MPa Izod impact strength: 100J / m Heat distortion temperature: 205 ° C Bending elastic modulus (during water absorption): 2900MPa When molded connector moldings, the appearance is smooth and weld lines are hardly noticeable. It was Comparative Example 5 40% by weight of the modified polypropylene resin used in Example 1,
Nylon 66 / 6T with relative viscosity of 2.55 (66 / 6T =
55/45% by weight) Mixture 10 of 60% by weight copolymer
A mixture of 0 parts by weight and 10 parts by weight of glass fibers having a fiber diameter of 13 μ was melt-kneaded and pelletized by the same method as in Example 1.

The pellets obtained here were vacuum-dried in the same manner as in Example 1, and then ASTM test pieces were molded under the same molding conditions. However, molding was carried out due to the large amount of component (b) and the absence of component (c). The flowability was poor and flow marks were generated on the surface of the test piece. The results of measuring the physical properties of the obtained test piece are as follows, but it was found that the toughness was inferior.

It is presumed that this is because the interfacial adhesion between the glass fiber and the polypropylene resin decreased with the increase in the amount of the polypropylene resin, and therefore the toughness decreased. Tensile strength: 70 MPa Izod impact strength: 90 J / m When a connector molded product was molded, a weld line was conspicuous due to poor molding fluidity and the calcium chloride resistance cycle test was carried out. After passing, it was found that it could not be used as a connector product because of cracking from the weld part.

[0041]

The connector resin composition of the present invention is excellent in heat resistance, rigidity upon absorption of water, toughness, dimensional stability, and anti-freezing property against roads, and is suitable as a molding material for connectors.

[Brief description of drawings]

FIG. 1 is a schematic view of a connector molded product, (A) is a front view, (B) is a plan view, and (C) is a side view.

[Explanation of symbols]

 1 Connector molded product

Claims (5)

[Claims] 1. A polyamide resin containing (a) an aromatic ring as a molecular constitutional unit: 55 to 84% by weight. (B) a modification modified with a graft monomer selected from unsaturated carboxylic acids, their acid anhydrides or their derivatives. One modified polyolefin resin 35 selected from either polypropylene resin or modified polyethylene resin
15% by weight (c) Modified with a grafting monomer selected from unsaturated carboxylic acid, its acid anhydride or its derivative, and has a crystallinity of 0 to 20% by X-ray and an ethylene content of 70 to 95.
Resin composition for connectors, wherein (d) 0 to 100 parts by weight of the inorganic reinforcing material is blended with 100 parts by weight of a mixture consisting of 10 to 1% by weight of a modified ethylene / α-olefin random copolymer of mol%. 2. The resin for a connector according to claim 1, wherein the polyamide resin having an aromatic ring as a molecular constitutional unit is nylon 6 or a copolyamide of nylon 66 and a polyamide having an aromatic ring. Composition. 3. The polyamide resin having an aromatic ring as a molecular constitutional unit is a copolyamide of nylon 66, a terephthalic acid component unit, and a polyamide comprising an aliphatic diamine component unit. The resin composition for a connector according to 1. 4. The melting point of the polyamide resin containing an aromatic ring in the molecular constitution unit is in the range of 270 to 320 ° C.
The resin composition for a connector as described. 5. The melting point of the copolyamide is 270 to 30.
The resin composition for a connector according to claim 3, which is in the range of 0 ° C.