JP2001279093A - Polyamide resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a polyamide-based resin composition capable of making a molding having excellent dimensional stability after water absorption, excellent abrasion resistance and sliding properties. SOLUTION: This polyamide resin composition comprises (A) a semiaromatic polyamide constituted of a repeating unit consisting of a dicarboxylic acid unit composed of 47-63 mol% of a terephthalic acid unit and a diamine unit composed of a 1,6-diaminohexane unit, having 1.15-1.40 dl/g intrinsic viscosity and (B) a modified polyolefin composition which is a modified polyolefin composition obtained by modifying a polyolefin composition composed of an ultra-high- molecular-weight polyolefin having 6-40 dl/g intrinsic viscosity and a polyolefin having 0.1-5 dl/g intrinsic viscosity with an unsaturated carboxylic acid and has a modification amount of the unsaturated carboxylic acid in a range of 0.01-5 wt.% based on the polyolefin composition in the ratio of 65-75 wt.% of the component (A) and 35-25 wt.% of the component (B) based on the total of the components (A) and (B).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a novel polyamide resin composition. More specifically, the present invention relates to a polyamide resin having high dimensional stability, excellent wear resistance, and suitable for producing a molded article having excellent sliding characteristics.

[0002]

BACKGROUND OF THE INVENTION Polyamides have excellent heat resistance, oil resistance, moldability, rigidity, toughness, etc. and are therefore used in power tools, general industrial parts, machine parts, electronic parts, automotive interior and exterior. It is widely used as various functional parts such as parts, engine room parts, and automotive electrical parts.

[0003] However, when compared with metal materials and the like, polyamide has a high friction coefficient, which is a sliding property, and is insufficient in sliding property. For this reason, attempts have been made to improve the sliding properties by blending additives such as a polyolefin component with such a synthetic resin.

For example, JP-A-3-285952 discloses that a terephthalic acid component unit of 30 to 100 mol% and an aromatic dicarboxylic acid component unit other than terephthalic acid of 0 to 40 mol% are disclosed.
Mole% and / or aliphatic dicarboxylic acid component unit 0
A semiaromatic polyamide having 70 mol% of an aromatic dicarboxylic acid component unit (a) and an aliphatic and / or alicyclic alkylenediamine component unit (b);
A polyamide composition comprising a modified polyethylene having an intrinsic viscosity [η] of 0.8 to 35 dl / g is disclosed.

JP-A-3-143957 discloses that a terephthalic acid component unit of 60 to 100 mol% and an aromatic dicarboxylic acid component unit other than terephthalic acid of 0 to 40 mol% are disclosed.
An aromatic polyamide having an aromatic dicarboxylic acid component unit (a) having a composition of mol% and a linear aliphatic alkylenediamine component unit (b) having 6 to 18 carbon atoms, and a specific glass fiber. A polyamide composition is disclosed.

A molded article formed from such a composition containing an aromatic polyamide is excellent in chemical properties such as heat resistance, mechanical properties, and oil resistance, but is easily worn by long-term sliding. There was a problem.

Japanese Patent Application Laid-Open No. 4-351647 discloses, as a sliding property improving agent to be incorporated in polyamide such as nylon 6, (A) ultrahigh molecular weight polyethylene having an intrinsic viscosity [η] of 6 dl / g or more. And (B) polyethylene having an intrinsic viscosity [η] of 0.1 to 5 dl / g, and the (A) ultrahigh molecular weight polyethylene and / or
Or (B) a sliding property improver obtained by modifying polyethylene with an unsaturated carboxylic acid. In this publication, aromatic polyamides are also exemplified as polyamides. However, when a sliding property improving agent is used for a polyamide having a specific intrinsic viscosity and containing a terephthalic acid component, the sliding properties are improved. There is no description.

Further, JP-A-10-114896 discloses a composition for a sliding member comprising a polyamide resin such as nylon 6, an unsaturated dicarboxylic acid-modified polyolefin resin, and an oil component such as silicone oil. Is disclosed.

[0009] However, molded articles formed from a composition containing an aliphatic polyamide such as nylon 6 are excellent in abrasion resistance and slidability, but the dimensions of the molded articles change due to water absorption of the polyamide over time. There was a problem of doing.

Under such circumstances, dimensional stability is high,
There has been a demand for the emergence of a polyamide-based resin composition capable of producing a molded article having excellent wear resistance and sliding properties.

[0011]

The object of the present invention is to provide excellent dimensional stability after water absorption,
It is an object of the present invention to provide a polyamide resin composition capable of producing a molded article having excellent wear resistance and slidability.

[0012]

The polyamide resin composition according to the present invention comprises (A) a terephthalic acid component unit and an adipic acid component unit, and the terephthalic acid component unit is contained in an amount of 47 to 63 mol%.
Is formed from a repeating unit containing a dicarboxylic acid component unit and a diamine component unit consisting of 1,6-diaminohexane component units, and has an intrinsic viscosity of 1.15 to 1.40 dl / g measured in concentrated sulfuric acid at 30 ° C. (B) an ultrahigh molecular weight polyolefin having an intrinsic viscosity of 6 to 40 dl / g measured in a decalin solvent at 135 ° C., and a low-molecular weight polyolefin having an intrinsic viscosity of 0.1 to 5 dl / g. A modified polyolefin composition obtained by modifying a polyolefin composition comprising a polyolefin having a molecular weight or a high molecular weight with an unsaturated carboxylic acid or a derivative thereof, wherein the modified amount of the unsaturated carboxylic acid or the derivative thereof is 0 to the polyolefin composition. And a modified polyolefin composition comprising (A) a semi-aromatic polyamide and (B) a modified polyolefin. The total amount of goods, the (A) a semiaromatic polyamide 65-75 wt%, is characterized by containing the (B) modified polyolefin composition in a proportion of 35 to 25 wt%.

That is, in the present invention, the above-mentioned specific semi-aromatic polyamide is selected from the semi-aromatic polyamides, and a specific modified polyolefin composition (B) is blended with this semi-aromatic polyamide (A). This is an important feature of the above.

By employing such a combination, a polyamide resin composition which is excellent in dimensional stability after water absorption, and which can provide a molded article having excellent wear resistance and dynamic friction coefficient can be obtained.

Further, the polyamide resin composition of the present invention
Heat-resistant deformation inherent in semi-aromatic polyamide,
It has excellent mechanical properties such as impact resistance and chemical and physical properties.

[0016]

DETAILED DESCRIPTION OF THE INVENTION The polyamide resin composition according to the present invention will be specifically described below. The polyamide resin composition according to the present invention contains (A) a specific semi-aromatic polyamide and (B) a modified polyolefin composition. [Semi-aromatic polyamide (A)] The semi-aromatic polyamide (A) used in the present invention comprises a specific dicarboxylic acid component unit,
And a repeating unit containing a diamine component unit.

The dicarboxylic acid component unit constituting the semi-aromatic polyamide comprises a terephthalic acid component unit and an adipic acid component unit. This semi-aromatic polyamide (A) has 100 units of all dicarboxylic acid component units present in the polyamide.
In terms of mol%, the terephthalic acid component unit is contained in an amount of 47 to 63 mol%, preferably 50 to 60 mol%, more preferably 52 to 58 mol%.

The terephthalic acid component unit is 47 to 63 mol%
Within this range, a dimensional change due to water absorption is reduced, and a molded article having excellent wear resistance can be produced. When the content of terephthalic acid in all dicarboxylic acid component units exceeds 63 mol%, when a polyamide molded product is produced, the rigidity of the molded product becomes too high, and the wear resistance may be reduced. On the other hand, when the content of the terephthalic acid component unit is less than 47 mol%, the water absorption increases, and the dimensional change due to water absorption may increase.

The semi-aromatic polyamide used in the present invention is formed of a repeating unit containing a dicarboxylic acid component unit and a diamine component unit composed of 1,6-diaminohexane component units.

The semi-aromatic polyamide used in the present invention has an intrinsic viscosity [η] measured at a temperature of 30 ° C. in concentrated sulfuric acid.
But 1.15 to 1.40 dl / g, preferably 1.20 to
1.40 dl / g, more preferably 1.30 to 1.40 dl
It is preferably in the range of / g.

When the intrinsic viscosity [η] of the semi-aromatic polyamide is within the above range, the moldability of the polyamide composition is improved. Further, a molded product made from a polyamide composition containing such a semi-aromatic polyamide also has excellent wear resistance during sliding. If the intrinsic viscosity [η] of the semi-aromatic polyamide exceeds 1.40 dl / g, the resin viscosity may increase and the moldability may deteriorate, and 1.15 dl / g.
If it is less than the above, the abrasion resistance of the produced molded product during sliding may be reduced.

The semi-aromatic polyamide used in the present invention generally has a melting point of 280 to 330 ° C., and often has a melting point in the range of 290 to 320 ° C. In addition, this semi-aromatic polyamide has excellent heat resistance and low water absorption.

Semi-aromatic polyamide (A) as described above
Can be produced by polycondensation of a dicarboxylic acid component and a diamine component. Specifically, terephthalic acid, adipic acid, and 1,6-diaminohexane are mixed in an aqueous medium, and heated under pressure in the presence of a catalyst such as sodium hypophosphite to first form a polyamide precursor. And then melt-polymerizing this polyamide precursor. When producing the polyamide precursor, a molecular weight modifier such as benzoic acid may be blended.

The semi-aromatic polyamide used in the present invention is produced by mixing and melting and kneading at least two types of polyamides having different compositions so that the dicarboxylic acid component unit and the diamine component unit fall within the above ranges. You can also. [Modified polyolefin composition (B)] In the present invention, a polyolefin composition containing a specific ultrahigh molecular weight polyolefin (B-1) and a low molecular weight to high molecular weight polyolefin (B-2) is used as the modified polyolefin composition. And a modified polyolefin composition modified with an unsaturated carboxylic acid or its derivative (C).

Polyolefin Composition The polyolefin composition contains (B-1) an ultra-high molecular weight polyolefin and (B-2) a low to high molecular weight polyolefin.

Examples of ultra-high molecular weight polyolefins include ethylene, propylene, 1-butene, isobutene, 1-
Pentene, 2-methyl-1-butene, 3-methyl-1-butene,
1-hexene, 3-methyl-1-pentene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1- It consists of a homopolymer or a copolymer of α-olefin such as Icocene. In the present invention, an ethylene homopolymer and a copolymer containing ethylene as a main component and comprising ethylene and another α-olefin are preferred.

The intrinsic viscosity [η] of this ultrahigh molecular weight polyolefin (B-1) measured at 135 ° C. in a decalin solvent is 6
-40 dl / g, preferably 10 to 40 dl / g, more preferably 25 to 35 dl / g.

This ultra-high molecular weight polyolefin (B-1) is
Density (D: measured according to ASTM D1505) 0.9
It is preferably 20 g / cm ³ or more and less than 0.935 g / cm ³ .

The low molecular weight to high molecular weight polyolefin (B-2), which is a component of the polyolefin composition, comprises:
The (B-1) is not particularly limited as long as the intrinsic viscosity is lower than the ultrahigh molecular weight polyolefin, and usually, like the ultrahigh molecular weight polyolefin, the homopolymer of the α-olefin as described above. Or it consists of a copolymer. In the present invention, ethylene homopolymers and copolymers containing ethylene and other α-olefins and containing ethylene as a main component are preferred.

(B-2) The intrinsic viscosity [η] of low- or high-molecular-weight polyolefin measured at 135 ° C. in a decalin solvent is 0.1 to 5.0 dl / g, preferably 0.1 to 5.0 dl / g.
２2 dl / g. The difference between the intrinsic viscosity of the ultrahigh molecular weight polyolefin and the intrinsic viscosity of the low molecular weight to high molecular weight polyolefin is 23 to 39 dl / g, preferably 23 to 39 dl / g.
Desirably, it is 37 dl / g.

The (B-2) low molecular weight to high molecular weight polyolefin desirably has a density of 0.935 g / cm ³ or more. The (B-1) ultrahigh molecular weight polyolefin content in the polyolefin composition is from 5 to 45, based on the total amount of (B-1) ultrahigh molecular weight polyolefin and (B-2) low molecular weight to high molecular weight polyolefin. % By weight, preferably 10
It is desirably in the range of 30% by weight, more preferably 10 to 25% by weight.

(B-1) an ultra-high molecular weight polyolefin, and (B-2)
The intrinsic viscosity of a polyolefin composition comprising a low molecular weight to high molecular weight polyolefin is 5 to 15 dl / g,
Preferably 3 to 10 dl / g, more preferably 4 to 6 dl / g
Is desirably within the range.

Such a polyolefin composition is represented by (B-
1) It is prepared by mixing an ultrahigh molecular weight polyolefin and (B-2) a low molecular weight to high molecular weight polyolefin polyolefin by a known method.

Further, at the time of polymerization of the olefin, a multistage polymerization using a specific Ziegler type catalyst is carried out so that the (B-1) ultrahigh molecular weight polyolefin and the (B-2) low molecular weight or high molecular weight polyolefin polyolefin have a specific ratio. The polyolefin composition can be prepared by producing a mixture containing

As a method for preparing a polyolefin composition containing (B-1) an ultrahigh molecular weight polyolefin and (B-2) a low molecular weight or high molecular weight polyolefin by multi-stage polymerization, magnesium, titanium and halogen are essential components. A method is employed in which an olefin is subjected to multi-stage polymerization in the presence of a Ziegler-type catalyst formed from a highly active solid titanium catalyst component (a) and an organoaluminum compound catalyst component (b).

For example, first, in one polymerization step, the olefin is polymerized to produce the ultrahigh molecular weight polyolefin (B-1), and in another polymerization step, the olefin is polymerized in the presence of hydrogen. By producing (B-2) a low molecular weight or high molecular weight polyolefin, a composition comprising the (B-1) ultrahigh molecular weight polyolefin and (B-2) a low molecular weight or high molecular weight polyolefin can be obtained. .

The Ziegler type catalyst used in the multi-stage polymerization is a catalyst having a specific property composed of a solid titanium catalyst component and an organoaluminum compound catalyst component.

As the solid titanium catalyst component, for example, a highly active fine powdery catalyst having a narrow particle size distribution, an average particle size of about 0.01 to 5 μm, and a form in which several microspheres are fixed. It is preferred to use components. The highly active fine powdered titanium catalyst component having such properties can be obtained, for example, by contacting a liquid state magnesium compound with a liquid state titanium compound in the solid titanium catalyst component described in JP-A-56-811. It can be manufactured by strictly adjusting the precipitation conditions when depositing the solid product. For example, in the method disclosed in JP-A-56-811, a hydrocarbon solution in which magnesium chloride and a higher alcohol are dissolved and titanium tetrachloride are mixed at a low temperature, and then the temperature is raised to about 50 to 100 ° C. To precipitate a solid product, magnesium chloride 1
The precipitation is carried out under a strong stirring condition while a small amount of a monocarboxylic acid ester of about 0.01 to 0.2 mol coexists with respect to the mol. If necessary, it may be washed with titanium tetrachloride. In this way, a solid catalyst component satisfying both the activity and the particle state can be obtained. This catalyst component contains, for example, about 1 to 6% by weight of titanium and a halogen / titanium (atomic ratio) of about 5 to 9%.
0, magnesium / titanium (atomic ratio) in the range of about 4-50.

Further, the slurry of the solid titanium catalyst component obtained as described above is subjected to shearing treatment at high speed, and has a narrow particle size distribution and an average particle size of usually 0.0%.
What consists of microspheres in the range of 1 to 5 μm, preferably 0.05 to 3 μm is also suitably used as a highly active fine powdered titanium catalyst component. As a method of the high-speed shearing treatment, for example, a method of treating a slurry of a solid titanium catalyst component in an inert gas atmosphere using a commercially available homomixer for an appropriate time is employed. At that time, in order to prevent a decrease in catalytic performance, a method in which an organoaluminum compound in an equimolar amount with titanium is added in advance may be adopted. Furthermore, a method of removing coarse particles from the slurry after the treatment with a sieve may be employed. By these methods, a highly active fine powdered titanium catalyst component having the above fine particle diameter can be obtained.

Using this highly active fine powdery titanium catalyst component and an organoaluminum compound catalyst component, if necessary, in combination with an electron donor, pentane, hexane, heptane,
In a hydrocarbon solvent such as kerosene, slurry polymerization of an olefin alone or a monomer mixture containing an olefin as a main component, for example, in a multistage polymerization step of at least two or more stages under a temperature condition of 0 to 100 ° C. By doing so, a composition comprising the (B-1) ultrahigh molecular weight polyolefin and (B-2) a low molecular weight to high molecular weight polyolefin can be produced.

Specific examples of the organoaluminum compound catalyst component to be used include trialkylaluminums such as triethylaluminum and triisobutylaluminum; dialuminum chlorides such as diethylaluminum chloride and diisobutylaluminum chloride; alkyls such as ethylaluminum sesquichloride and the like. Aluminum sesquichloride and the like are used, and these are used alone or in combination of two or more. In this multi-stage polymerization step, at least two or more polymerization tanks are usually
A multi-stage polymerization apparatus connected in series is employed, for example, a two-stage polymerization method, a three-stage polymerization method,..., An n-stage polymerization method. Further, it is also possible to carry out a multi-stage polymerization method by a batch polymerization method in one polymerization tank. It is necessary to produce a specific amount of ultrahigh molecular weight polyolefin in at least one polymerization tank in this multi-stage polymerization step. The polymerization step for producing the ultrahigh molecular weight polyolefin may be a first-stage polymerization step, an intermediate polymerization step, or may be two or more stages. . Producing the ultrahigh molecular weight polyolefin (B-1) in the first stage polymerization step is preferred from the viewpoint of the polymerization treatment operation and the control of the physical properties of the produced polyolefin. In this polymerization step, an ultra-high molecular weight polyolefin having a predetermined intrinsic viscosity [η] is polymerized by polymerizing 15 to 40% by weight of the olefin polymerized in all the steps.
(B-1) is generated. Further, it is preferable to produce 18 to 37% by weight, particularly 21 to 35% by weight, of the monomer to be polymerized in the whole polymerization step to produce an ultrahigh molecular weight polyolefin (B-1) having a predetermined intrinsic viscosity.

In the multi-stage polymerization step, in the polymerization step for producing the ultra-high molecular weight polyolefin (B-1), the polymerization is carried out in the presence of the specific Ziegler type catalyst comprising the highly active titanium catalyst component and the organoaluminum catalyst component. Done. This polymerization can be carried out by a gas phase polymerization method or a liquid phase polymerization method. In any polymerization method, in the polymerization step for producing the ultrahigh molecular weight polyolefin (B-1), the polymerization reaction is carried out in the presence of an inert medium as required. For example, in the gas phase polymerization method,
If necessary, the reaction is carried out in the presence of a diluent comprising an inert medium. In the liquid phase polymerization method, the reaction is carried out in the presence of a solvent comprising an inert medium as necessary.

In the polymerization step for producing the ultra-high molecular weight polyolefin (B-1), about 0.001 to 20 milligram atoms per liter of medium, particularly about 0.1 to 0.1 milligram atoms per liter of the medium.
A highly active titanium catalyst component comprising an organoaluminum compound catalyst component in an amount of from about 005 to 10 milligram atoms and having an Al / Ti (atomic ratio) of about 0.1 to 1000, especially about 1 to 500. It is desirable to use. The temperature in the polymerization step for producing the ultrahigh molecular weight polyolefin (B-1) is usually about -20 to 120 ° C,
Preferably about 0-100 ° C, particularly preferably about 5-95 ° C
Range. Further, the pressure of the polymerization reaction may be in a pressure range in which liquid phase polymerization or gas phase polymerization is possible at the above temperature,
For example, it ranges from atmospheric pressure to about 100 kg / cm ² , preferably from atmospheric pressure to about 50 kg / cm ² . The polymerization time is
The production amount of the total polymerized polyolefin may be set so as to be about 1000 g or more, preferably about 2000 g or more per 1 mg atom of titanium in the highly active titanium catalyst component. Further, in the polymerization step, in order to produce the ultrahigh molecular weight polyolefin (B-1), it is preferable to carry out the polymerization reaction in the absence of hydrogen. Further, after the polymerization reaction is performed, the polymer can be once isolated and stored in an inert medium atmosphere.

As the inert medium used in the polymerization step for producing the ultrahigh molecular weight polyolefin (B-1), specifically, aliphatic solvents such as propane, butane, pentane, hexane, heptane, octane, decane and kerosene Hydrocarbons; alicyclic hydrocarbons such as cyclopentane and cyclohexane; aromatic hydrocarbons such as benzene, toluene and xylene; halogenated hydrocarbons such as dichloroethane, methylene chloride, chlorobenzene and the like.
These are used alone or in combination of two or more. Particularly, an aliphatic hydrocarbon is preferred.

In the above method, in the other polymerization steps other than the polymerization step for producing the (B-1) ultrahigh molecular weight polyolefin, the remaining monomer is subjected to a polymerization reaction in the presence of hydrogen to produce the (B-2) Low to high molecular weight polyolefins are produced. (B-1) If the polymerization step for producing the ultrahigh molecular weight polyolefin is the first polymerization step, the second and subsequent polymerization steps are performed in the presence of this hydrogen. (B-2) Low molecular weight to high molecular weight This is a process for producing a molecular weight polyolefin. When the (B-2) low molecular weight to high molecular weight polyolefin polymerization step is located after the (B-1) ultrahigh molecular weight polyolefin production step, the (B-2) low molecular weight to high molecular weight polyolefin In the polymerization step, a reaction mixture containing (B-1) ultra-high molecular weight polyolefin is supplied,
When the (B-2) low molecular weight to high molecular weight polyolefin polymerization step is located before the (B-1) ultrahigh molecular weight polyolefin is formed, the polymerization step (B-2)
-2) Low or high molecular weight polyolefin and (B-1)
An ultra-high molecular weight polyolefin is supplied and in each case the polymerization is carried out continuously. At that time, the raw material monomer mixture and hydrogen are usually supplied to the polymerization step.
When the polymerization step is a first-stage polymerization step, a catalyst comprising the highly active titanium catalyst component and the organoaluminum compound catalyst component is supplied, and when the polymerization step is a polymerization step of the second stage or later, Can use the catalyst contained in the polymerization reaction mixture produced in the previous step as it is, or if necessary, additionally replenish the above-mentioned highly active titanium catalyst component and / or organoaluminum compound catalyst component. Good.

The supply ratio of hydrogen in the polymerization step other than the polymerization step (B-1) for producing the ultrahigh molecular weight polyolefin is as follows:
It is usually in the range of 0.01 to 50 mol, preferably 0.05 to 30 mol, per 1 mol of the monomer supplied to the polymerization step.

The concentration of each catalyst component in the polymerization reaction mixture in the polymerization tank in the polymerization step other than the polymerization step (B-1) for producing the ultrahigh molecular weight polyolefin was such that the treated catalyst was used per 1 liter of polymerization volume. Approximately 0.1 when converted to titanium atoms.
001 to 0.1 milligram atoms, preferably about 0.00
5 to 0.1 milligram atoms, polymerized Al / Ti
(Atomic ratio) is about 1 to 1000, preferably about 2 to 500
It is preferable to adjust so that If necessary, an organoaluminum compound catalyst component may be additionally used. In the polymerization system, hydrogen, an electron donor, a halogenated hydrocarbon, and the like may be coexistent in order to adjust the molecular weight, the molecular weight distribution, and the like.

The polymerization temperature is in a temperature range in which slurry polymerization and gas phase polymerization are possible, and is about 40 ° C. or higher, more preferably about 50 to 100 ° C. The polymerization pressure is, for example, from atmospheric pressure to about 100 kg / cm ² , especially from atmospheric pressure to about 5 kg / cm ² .
A range of 0 kg / cm ² is recommended. The polymerization time is preferably set so that the amount of the polymer produced is about 1000 g or more, particularly preferably about 5000 g or more, per 1 mg atom of titanium in the titanium catalyst component.

(B-1) The polymerization steps other than the polymerization step for producing the ultrahigh molecular weight polyolefin can be carried out by a gas phase polymerization method or a liquid phase polymerization method.
Of course, different polymerization methods may be employed in each polymerization step. Among the liquid phase polymerization methods, a slurry suspension polymerization method is suitably employed. In any case, in the polymerization step, the polymerization reaction is usually carried out in the presence of an inert medium. For example, the gas phase polymerization method is carried out in the presence of an inert medium diluent, and the liquid phase slurry suspension polymerization method is carried out in the presence of an inert medium solvent. As the inert medium, the same inert media as those exemplified in the polymerization step (B-1) for producing the ultrahigh molecular weight polyolefin can be exemplified.

The multistage polymerization can be carried out in any of a batch system, a semi-continuous system and a continuous system. Graft modification of polyolefin composition Modified polyolefin composition (B) used in the present invention
In the above, the polyolefin composition is graft-modified with an unsaturated carboxylic acid or a derivative thereof.

As the unsaturated carboxylic acid used for the modification, specifically, acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, crotonic acid, endocis-bicyclo [2,2,1] Hept-5-en-2,
3-dicarboxylic acid (Nadic acid TM) and the like.

The derivatives include acid halides,
Esters, amides, imides, anhydrides and the like, specifically, maleenyl chloride, maleimide, acrylamide, methacrylamide, glycidyl methacrylate,
Maleic anhydride, citraconic anhydride, monomethyl maleate, dimethyl maleate, glycidyl maleate and the like can be mentioned. These modifying monomers may be used alone or in combination of two or more. Among these, maleic anhydride is preferred because it can obtain a molded product having high reactivity and good strength and appearance.

In the modified polyolefin composition used in the present invention, the amount of grafting of the above-mentioned modifying monomer is as follows: the ultrahigh molecular weight polyolefin (B-1) and the polyolefin (B-2).
Is preferably from 0.2 to 2.0% by weight, and more preferably from 0.7 to 1.3% by weight, based on 100% by weight of the total amount.

Method for Preparing Modified Polyolefin Composition A method for modifying a composition containing an ultra-high molecular weight polyolefin (B-1) and a low molecular weight to high molecular weight polyolefin (B-2) with the above-mentioned modifying monomer is a conventional method. Various known methods can be employed. For example, ultra high molecular weight polyolefin
(B-1) and low molecular weight to high molecular weight polyolefin (B-
A method comprising suspending or dissolving the composition containing 2) in a solvent, or usually, at a temperature of 80 to 200 ° C., adding and mixing a modifying monomer and a radical polymerization initiator and the like to carry out graft copolymerization, Or above the melting point, for example, 180-300
A method in which the modifying monomer (C) and the radical polymerization initiator are brought into contact with each other at a temperature of ° C. under melt-kneading.

Further, (B-1) an ultra-high molecular weight polyolefin and
(B-2) Both the low molecular weight or high molecular weight polyolefin may be modified with a modifying monomer in advance, and then both may be mixed. As the solvent used, specifically, toluene,
Aromatic hydrocarbon solvents such as xylene; aliphatic hydrocarbon solvents such as hexane, heptane, octane and decane; alicyclic hydrocarbon solvents such as cyclohexane and methylcyclohexane; trichloroethylene, perchloroethylene, dichloroethylene, dichloroethane, Chlorinated hydrocarbon solvents such as chlorobenzene; aliphatic alcohol solvents such as ethanol and isopropanol; ketone solvents such as acetone, methyl isobutyl ketone and methyl ethyl ketone; ester solvents such as methyl acetate, ethyl acetate and butyl acetate; Can be These solvents may be used alone or in combination of two or more.

Examples of the radical polymerization initiator include radical initiators such as organic peroxides and azo compounds. Specific examples of the organic peroxide include benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, m-trioil peroxide, di-t-butyl peroxide, dicumyl peroxide, (2,5- Dimethyl-
2,5-bis (t-butylperoxy) hexane, 2,5-dimethyl-2,5-bis (t-butylperoxy) hexyne-3, lauroyl peroxide, t-butylperoxyacetate, 2,5 -Dimethyl-2,5-di (benzoylperoxy) hexane, t-butylperoxybenzoate, t-butylperoxyisobutyrate, t-butylperoxyphenyl acetate, t-butylperoxy-s-octate, t -Butylperoxypivalate, cumylperoxypivalate, t-butylperoxyethyl acetate and the like.

Specific examples of the azo compound include azoisobutyronitrile, dimethylazoisobutyrate and the like. These radical initiators are used alone or in combination of two or more. [Polyamide composition] The polyamide composition according to the present invention comprises the above (A) semi-aromatic polyamide and (B) modified polyolefin composition, and (A) semi-aromatic polyamide and (B) modified polyolefin composition. For the total amount,
65-75% by weight of the semi-aromatic polyamide (A), preferably 67-73% by weight, more preferably 69-7% by weight.
1% by weight of the modified polyolefin composition (B)
-25% by weight, preferably 33-27% by weight, more preferably 31-29% by weight.

The resin composition according to the present invention contains a P in the polyamide composition as long as the object of the present invention is not impaired.
PS (polyphenylene sulfide), PPE (polyphenyl ether), PES (polyether furfon),
A heat-resistant resin such as PEI (polyetherimide), LCP (liquid crystal polymer) and modified products of these resins can also be blended.

Further, the polyamide resin composition of the present invention contains an antioxidant (heat stabilizer) such as a phosphorus antioxidant, a phenol antioxidant, an amine antioxidant, and a sulfur antioxidant. can do.

Examples of the phosphorus-based antioxidants include 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, triphenyl phosphite, 2-ethylhexyl phosphate, dilauryl phosphite, trilauryl phosphite and trilauryl phosphite. -iso-octyl phosphite, tris (2,4-di-tert-butylphenyl) phosphite, trilauryl phosphite, trilauryl-di-thiophosphite, trilauryl-tri-
Thiophosphite, trisnonylphenyl phosphite, distearylpentaerythritol diphosphite, tris (monononylphenyl) phosphite, tris (dinonylphenyl) phosphite, trioctadecylphosphite, 1,1,3-tris (2 -Methyl-di-tridecylphosphite-5-tert-butylphenyl) butane, 4,4'-
Butylidene-bis (3-methyl-6-tert-butyl) tridecyl phosphite, 4,4'-butylidene-bis (3-methyl-6-tert
-Butyl-di-tridecyl) phosphite, bis (2,4-di-te
(rt-butylphenyl) pentaerythritol-di-phosphite, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol-di-phosphite, tetrakis (2,4
-Di-tert-butylphenyl) 4,4'-bisphenylenediphosphonite, distearylpentaerythritol diphosphite, tridecylphosphite, tristearylphosphite, 2,2'-methylenebis (4,6-diphenyl -tert-butylphenyl) octyl phosphite, sorbitol-tris-phosphite-distearyl-mono-C30-diol ester and bis (2,4,6-tri-tert-butylphenyl) pentaerythritol diphosphite Can be. Among these, bis (2,4-di-tert-butylphenyl) pentaerythritol-di-phosphite and bis (2,6-di-te
(rt-butyl-4-methylphenyl) pentaerythritol-di
Pentaerythritol-di-phosphite-based phosphorus antioxidants such as -phosphite and tetrakis
(2,4-di-tert-butylphenyl) 4,4′-bisphenylenediphosphonite.

Examples of phenolic antioxidants include 3,3
9-bis {2- [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyl] -1,1-dimethylethyl} -2,4,
8,10-tetraoxaspiro [5,5] undecane, 2,6-di-ter
t-butyl-p-cresol, 2,4,6-tri-tert-butylphenol, n-octadecyl-3- (4'-hydroxy-3 ', 5'-di-t
ert-butylphenol) propionate, styrenated phenol, 4-hydroxy-methyl-2,6-di-tert-butylphenol, 2,5-di-tert-butyl-hydroquinone, cyclohexylphenol, butylhydroxyanisole,
2,2'-methylene-bis- (4-methyl-6-tert-butylphenol), 2,2'-methylene-bis- (4-ethyl-6-tert-butylphenol), 4,4'-iso-propyl Redenebisphenol,
4,4'-butylidene-bis (3-methyl-6-tert-butylphenol), 1,1-bis- (4-hydroxy-phenyl) cyclohexane, 4,4'-methylene-bis- (2,6-di -tert-butylphenol), 2,6-bis (2'-hydroxy-3'-tert-butyl-
5'-methylmethylbenzyl) 4-methyl-phenol, 1,1,3
-Tris (2-methyl-4-hydroxy-5-tert-butyl-phenyl) butane, 1,3,5-tris-methyl-2,4,6-tris (3,5-
Di-tert-butyl-4-hydroxy-benzyl) benzene,
Tetrakis [methylene-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] methane, tris (3,
5-di-tert-butyl-4-hydroxyphenyl) isocyanurate, tris [β- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyl-oxyethyl] isocyanate, 4,4′-thiobis ( 3-methyl-6-tert-butylphenol), 2,2′-thiobis (4-methyl-6-tert-butylphenol), 4,4′-thiobis (2-methyl-6-tert-butylphenol), and N, N'-hexamethylenebis (3,5-zy tert
-Butylphenol-4-hydroxycinnamamide). Examples of amine antioxidants include 4,4′-bis (α, α-dimethylbenzyl) diphenylamine, phenyl-α-naphthylamine, and phenyl-β-
Naphthylamine, N, N'-diphenyl-p-phenylenediamine, N, N'-di-β-naphthyl-p-phenylenediamine, N-cyclohexyl-N'-phenyl-p-phenylenediamine, N-
Phenyl-N'-isopropyl-p-phenylenediamine, aldol-α-naphthylamine, 2,2,4, -trimethyl-1,2-
Polymer of dihydroquinone and 6-ethoxy-2,2,4-
Trimethyl-1,2-dihydroquinoline can be mentioned.

Further, examples of sulfur-based antioxidants include thiobis (β-naphthol), thiobis (N-phenyl-
β-naphthylamine), 2-mercaptobenzothiazole,
Mention may be made of 2-mercaptobenzimidazole, dodecylmercaptan, tetramethylthiuram monosulfide, tetramethylthiuram disulfide, nickel dibutyl dithiocarbamate, nickel isopropyl xanthate, dilauryl thiodipropionate and distearyl thiodipropionate.

These antioxidants can be used alone or in combination. Among these antioxidants, it is particularly preferable to use a phosphorus-based antioxidant alone or in combination with another antioxidant. Furthermore, in the polyamide resin composition of the present invention,
As the inorganic reinforcing material, various inorganic fillers having a shape such as fibrous, powdery, granular, plate-like, needle-like, cloth-like, and mat-like can be blended.

For example, preferable examples of the fibrous inorganic filler include glass fiber, carbon fiber, asbestos fiber and boron fiber. Among them, glass fiber is particularly preferred. The use of glass fibers improves the mechanical properties such as tensile strength, bending strength and flexural modulus of the molded product, and the heat resistance properties such as thermal deformation temperature. The average length of the glass fiber as described above is usually 0.1 to 20 m.
m, preferably in the range of 0.3 to 6 mm, and the aspect ratio is usually in the range of 10 to 2000, preferably 30 to 600. It is preferable to use glass fibers having an average length and an aspect ratio within such ranges. Such a glass fiber is usually used in an amount of 200 parts by weight or less, preferably 5 to 18 parts by weight, per 100 parts by weight of the resin component.
0 parts by weight, more preferably 5 to 150 parts by weight.

In addition to the above-mentioned fibrous inorganic fillers, examples of various fillers having a shape such as powder, granule, plate, needle, cloth and mat used in the present invention include: Powdery or plate-like inorganic compounds such as silica, silica alumina, alumina, calcium carbonate, titanium dioxide, talc, wollastonite, diatomaceous earth, clay, kaolin, spherical glass, mica, gypsum, redwood, magnesium oxide and zinc oxide , Potassium-titanate and the like.

These fillers can be used as a mixture of two or more kinds. Further, these fillers can be used after being treated with a silane coupling agent or a titanium coupling agent. The average particle size of such a filler is usually 0.1 to 200 μm, preferably 1 to 10 μm.
It is in the range of 0 μm.

Such a filler is used in an amount of usually 200 parts by weight or less, preferably 100 parts by weight or less, particularly preferably 1 to 50 parts by weight, based on 100 parts by weight of the resin component. Is done.

Further, the polyamide resin composition of the present invention comprises:
Organic fillers, heat stabilizers, weathering stabilizers, antistatic agents, anti-slip agents, anti-blocking agents, anti-fogging agents, lubricants, pigments, dyes, natural Additives such as oils, synthetic oils and waxes may be included.

Examples of the organic filler include polyparaphenylene terephthalamide, polymetaphenylene terephthalamide, polyparaphenylene isophthalamide, polymetaphenylene isophthalamide, a condensate of diaminodiphenyl ether and terephthalic acid (isophthalic acid), and para ( Wholly aromatic polyamides such as condensates of (meth) aminobenzoic acid; wholly aromatic polyamide-imides such as condensates of diaminodiphenyl ether with trimellitic anhydride or pyromellitic anhydride; wholly aromatic polyesters; wholly aromatic polyimides; Heterocycle-containing compounds such as benzimidazole and polyimidazophenanthroline; and secondary processed products such as powdery, plate-like, fibrous or cloth-like materials formed from polytetrafluoroethylene and the like. Door can be.

The polyamide resin composition according to the present invention is melt-kneaded with (A) a semi-aromatic polyamide, (B) a modified polyolefin composition, and, if necessary, the above-mentioned additives so that the above-mentioned composition is obtained. Thus, it can be prepared. Melt kneading temperature is not particularly limited, but usually,
The temperature may be in the range of 200 to 300 ° C, preferably 200 to 270 ° C. The kneading can be performed using a known one such as a single screw extruder, a twin screw extruder, and a Banbury mixer.

The polyamide resin composition according to the present invention can be used to produce a molded article having a desired shape by utilizing a usual melt molding method, for example, a compression molding method, an injection molding method or an extrusion molding method. .

For example, the polyamide resin composition of the present invention is put into an injection molding machine having a cylinder temperature adjusted to about 350 to 300 ° C., melted, and introduced into a mold having a predetermined shape. Moldings can be manufactured.

The shape of a molded product produced using the polyamide resin composition of the present invention is not particularly limited. For example, electric tools and general industrial parts, mechanical parts such as gears and cams, printed wiring boards and Various forms of molded articles such as electronic parts such as housings for electronic parts can be manufactured, and they are also suitable as resins for forming automobile interior / exterior parts, engine room interior parts, automobile electric parts, and the like. .

Further, the polyamide resin composition of the present invention
It can also be used as a resin for manufacturing connectors for interconnecting electronic circuits.

[0075]

According to the present invention, there can be obtained a resin composition which is excellent in dimensional change stability against water absorption over time, excellent in abrasion resistance and capable of producing a molded article having extremely excellent sliding characteristics.

A molded product made from such a polyamide resin composition has high mechanical strength, excellent abrasion resistance, and excellent dimensional stability against water absorption.

[0077]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the scope of the invention. In the examples, performance evaluation of dimensional stability, wear resistance, and dynamic friction coefficient was performed by the following method.

Dimensional stability (after water absorption): A square plate having a thickness of 2 mm was prepared using a mold whose original size was measured, and the square plate was heated at 23 ° C.
The dimensional change rate after water absorption for 96 hours was measured and evaluated according to the following scale.

○: less than 0.5% Δ: 0.5% or more and less than 1.0% ×: 1.0% or more Abrasion resistance: Using a wear wheel tester (manufactured by Toyo Seiki) in accordance with JIS K7204 , Load 1.0Kgf, rotation speed 6
Under the condition of 0 rpm, using a wear wheel of H-22, 500
The amount of wear after 0 rotation was measured, and the amount of wear was evaluated according to the following scale.

[0080] Wear amount evaluation ◎: less than ^{50mm 3 ○: 50~100mm 3 △:} 100~300mm 3 ×: greater than 300 mm ³ the dynamic friction coefficient: according to JIS K7218-A method, Matsubara type friction wear tester (Toyo Baldwin ), And slided 3 km under the conditions of a compressive load of 7.5 kgf / cm ² and a sliding speed of 12 m / min to determine the dynamic friction coefficient. The mating material was S45C and the sliding surface roughness was 6 s. Test piece: Injection molded plate (130mm × 120mm × 3m
m) was used. The dynamic friction coefficient was evaluated on the following scale.

Evaluation of dynamic friction coefficient ○: less than 0.15 Δ: 0.15 to 0.30 ×: greater than 0.30

[0082]

Production Example 1 Production of Semiaromatic Polyamide (A-1) 25,400 g (219 mol) of 1,6-diaminohexane, 24700 g (149 mol) of terephthalic acid, and 10600 g (64 mol) of isophthalic acid, and hypoxia as a catalyst 45 g (0.425 mol) of sodium phosphate, 325 g (2.66 mol) of benzoic acid as a molecular weight regulator,
And 14800 ml of ion-exchanged water were charged into a 100-liter reactor, and after nitrogen replacement, at 250 ° C. and 35 kg /
The reaction was performed for 1 hour under the condition of cm ² . The molar ratio between terephthalic acid and isophthalic acid was 70:30. After one hour, the reaction product generated in the reactor is discharged to a receiver connected to the reactor and set at a pressure of about 10 kg / cm ² lower, and has an intrinsic viscosity [η] of 0.10 dl /.
Thus, 54500 g of a polyamide precursor was obtained.

Next, the polyamide precursor is dried,
Melt polymerization was performed at a cylinder set temperature of 330 ° C. using a twin-screw extruder to obtain a semi-aromatic polyamide. The content of terephthalic acid component units in all dicarboxylic acid component units in the obtained aromatic polyamide was 70 mol%, and the content of isophthalic acid component units was 30 mol%. The semi-aromatic polyamide had an intrinsic viscosity [η] (measured in concentrated sulfuric acid at 30 ° C.) of 1.10 dl / g and a melting point of 325 ° C.

[0084]

Production Examples 2 to 4 Production of semi-aromatic polyamide (A-2) 26450 g (228 mol) of 1,6-diaminohexane, 20630 g (124 mol) of terephthalic acid and 14850 g (102 mol) of adipic acid and a catalyst 48 g (0.450 mol) of sodium hypophosphite, 342 g (2.80 mol) of benzoic acid as a molecular weight regulator and 6200 ml of ion-exchanged water were charged into a 100 liter reactor, and after nitrogen replacement, at 250 ° C., 35 kg / cm
^The reaction was performed under the conditions of ² for 1 hour. The molar ratio of terephthalic acid to adipic acid was 55:45. After one hour,
The reaction product produced in the reactor is discharged to a receiver connected to the reactor and set at a pressure of about 10 kg / cm ² lower, and a polyamide precursor having an intrinsic viscosity [η] of 0.15 dl / g is taken out. 55900 g were obtained.

Next, the polyamide precursor is dried,
Using a twin-screw extruder, melt polymerization was performed at a cylinder set temperature of 340 ° C. to obtain a semi-aromatic polyamide. The composition of this aromatic polyamide is as follows. The content of the terephthalic acid component unit in the dicarboxylic acid component unit was 55 mol%, and the content of the adipic acid component unit was 45 mol%. In addition, the intrinsic viscosity [η] (30
C. in concentrated sulfuric acid) was 1.00 dl / g and the melting point was 312 ° C. Production of Semi-Aromatic Polyamide (A-3, A-4) In the preparation of the semi-aromatic polyamide (A-2), 16880 g (102 mol) of terephthalic acid, 18150 g (124 mol) of adipic acid, and the compounding ratio ( Mole ratio)
5:55, except for the semi-aromatic polyamide (A-2)
In the same manner as in the production of the above, semi-aromatic polyamide (A-3) was prepared. Further, in the preparation of the semi-aromatic polyamide (A-2), terephthalic acid was 24380 g (147 mol), adipic acid was 11550 g (79 mol), and the mixing ratio (molar ratio) was 65:35. In the same manner as in the production of the aromatic polyamide (A-2), the semi-aromatic (A-
4) A polyamide was prepared. Table 1 shows the composition and physical properties of these aromatic polyamides.

[0086]

Production Example 5 Production of Semiaromatic Polyamide (A-5) 26450 g (228 mol) of 1,6-diaminohexane, 20560 g (124 mol) of terephthalic acid, and 14800 g (101 mol) of adipic acid were used as a catalyst for hypoxia. 48 g (0.450 mol) of sodium phosphate, 172 g (1.41 mol) of benzoic acid as a molecular weight regulator and 6200 ml of ion-exchanged water were charged into a 100-liter reactor, and after nitrogen replacement, 250 ° C., 35 kg / cm
^The reaction was performed under the conditions of ² for 1 hour. The molar ratio of terephthalic acid to adipic acid was 55:45. After one hour,
The reaction product produced in the reactor is discharged to a receiver connected to the reactor and set at a pressure of about 10 kg / cm ² lower, and a polyamide precursor having an intrinsic viscosity [η] of 0.15 dl / g is taken out. 55900 g were obtained.

Next, the polyamide precursor is dried,
Using a twin-screw extruder, melt polymerization was performed at a cylinder set temperature of 340 ° C. to obtain a semi-aromatic polyamide. The composition of this aromatic polyamide is as follows. The content of the terephthalic acid component unit in the dicarboxylic acid component unit was 55 mol%, and the content of the adipic acid component unit was 45 mol%. In addition, the intrinsic viscosity [η] (30
C. in concentrated sulfuric acid) was 1.35 dl / g and the melting point was 312 ° C.

[0088]

[Table 1]

[0089]

[Production Example 6] Graft-modified polyethylene composition (B)
Production polyethylene composition (Ultra high molecular weight polyethylene [135 ° C
[Η] in decalin: 31 dl / g] 20% by weight, low molecular weight polyethylene [[η] in 135 ° C decalin: 1 dl / g] 80% by weight), 100 parts by weight, maleic anhydride 0.8 part by weight, and Organic peroxide [Nippon Yushi Co., Ltd. Perhexin-2
5B] was mixed with a Hexchel mixer, and the resulting mixture was melt-graft-modified with a 65 mmφ single screw extruder set at 250 ° C. to obtain a graft-modified polyethylene composition. The amount of maleic anhydride grafted on this graft-modified polyethylene composition (B) was measured by IR analysis and found to be 0.8% by weight.

The intrinsic viscosity of the polyethylene composition measured at 135 ° C. in decalin was 5 dl / g.

[0091]

[Production Example 7] Production of graft-modified polyethylene (C) 100 parts by weight of high-density polyethylene [density: 0.95, [η] in decalin at 135 ° C: 3.7 dl / g], 0.8 parts by weight of maleic anhydride And 0.07 parts by weight of an organic peroxide [Nippon Oil & Fats Co., Ltd. Perhexin-25B] were mixed with a Hexchel mixer, and the obtained mixture was set at 65 ° C. at 250 ° C.
Graft modified polyethylene was obtained by melt graft modification with a single screw extruder of mφ. The amount of maleic anhydride grafted on this graft-modified polyethylene was measured by IR analysis to be 0.8% by weight.

[0092]

Example 1 70 parts by weight of the semi-aromatic polyamide (A-5) obtained in Production Example 5 and 30 parts by weight of the graft-modified polyethylene composition (B) obtained in Production Example 6 were mixed in the proportions shown in Table 1. And then melt-mixed under a cylinder temperature condition of 300 to 335 ° C. using a 30 mmφ vent-type twin screw extruder to produce pellets of a semi-aromatic polyamide resin composition. Injection molded test pieces were prepared using the pellets thus obtained, and the performance described above was evaluated.

Table 2 shows the evaluation results.

[0094]

Comparative Examples 1 to 7 The semi-aromatic polyamides (A-1 to 4) used in Production Examples 1 to 4 and the semi-aromatic polyamides (A-
5) or nylon 6 [Toray Co., Ltd. Alamin CM100]
7] to prepare a semi-aromatic polyamide resin composition by mixing with the graft-modified polyethylene composition (B) or the graft-modified polyethylene (C) at the composition and ratio shown in Table 1. Was evaluated.

Table 2 shows the results.

[0096]

[Table 2]

Continued on the front page F-term (reference) 4J001 DA01 DB04 DC14 EB08 EB37 EC08 FA01 FB06 FC03 HA01 HA02 HA05 JA02 JA04 JA05 JA07 JB02 JC01 4J002 BB212 BB213 CF031 CF051 FD010 FD070 4J100 AA02P AA03P AA15AAAP AA07P AA07A AAP HC29 HC30 HC50 HC63

Claims (1)

[Claims] (A) A terephthalic acid component unit and an adipic acid component unit.
A dicarboxylic acid component unit contained at a ratio of 3 mol%;
A semi-aromatic polyamide formed from a repeating unit containing a diamine component unit composed of 6-diaminohexane component units and having an intrinsic viscosity in the range of 1.15 to 1.40 dl / g measured in concentrated sulfuric acid at 30 ° C .; A polyolefin composition comprising an ultrahigh molecular weight polyolefin having an intrinsic viscosity of 6 to 40 dl / g measured in a 135 ° C decalin solvent and a low molecular weight to high molecular weight polyolefin having an intrinsic viscosity of 0.1 to 5 dl / g, A modified polyolefin composition modified with an unsaturated carboxylic acid or a derivative thereof, wherein the amount of modification of the unsaturated carboxylic acid or a derivative thereof is in the range of 0.01 to 5% by weight based on the polyolefin composition. And (A) the semi-aromatic polyamide, and the total amount of the (A) semi-aromatic polyamide and (B) the modified polyolefin composition. Amide 65-75 wt%, (B) the modified polyolefin composition of a polyamide resin composition characterized in that it contains a proportion of 35 to 25 wt%.