JP3460792B2 - Polyamide resin, polyamide resin composition and molded article - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention has excellent mechanical properties, heat resistance, moisture resistance, and moldability, and is particularly useful for rigidity and dimensional stability when placed in a high humidity environment, and for automobile engine cooling water. The present invention relates to a polyamide resin composition having less deterioration of a polymer material when exposed to an antifreeze at a high temperature and having excellent strength and dimensional stability.

More specifically, the polyamide resin has a high toughness, which maintains the excellent toughness, which is a characteristic of the polyamide resin, and has a very small decrease in rigidity even after being exposed to a high humidity environment for a long time.
Regarding the polyamide resin and its composition having high humidity resistance and high dimensional stability, it is mainly used for connectors in automobile engine rooms and also for radiator tank parts, water pump parts, etc. under contact with cooling water in automobile engine rooms. The present invention relates to a polyamide resin and a composition thereof, which are preferably used for parts applications.

[0003]

2. Description of the Related Art Polyamide resins represented by nylon 6 and nylon 66 have excellent characteristics as engineering plastics and are widely used in various industrial fields such as automobiles and electric / electronics.

In recent years, in automobile parts, especially in harness connector applications used in the engine room, along with the high performance and high output of engine performance, harsh operating environment such as temperature rise and high humidity in the engine room There is an ever-increasing demand for materials that can maintain high binding and connection functions even under the conditions below. Nylon 6 and nylon 66, which are commonly used, meet these sophisticated requirements.
In the case of resin, there are problems in that rigidity is lowered due to water absorption, the connection function is impaired, dimensional change is large, and dimensional stability is poor.

Recently, as a polyamide resin which can be used even under such a severe environment, Japanese Patent Laid-Open No. 59-1 has been proposed.
55426, JP-A-62-156130,
Furthermore, JP-A-3-201375 and JP-A-3-776.
No. 1 discloses a high melting point copolyamide resin containing terephthalic acid and / or isophthalic acid. These polyamide resins have a high melting point and at the same time suppress the water absorption due to the introduction of aromatic dicarboxylic acid units, exhibit high rigidity and dimensional stability even in a high humidity environment, and have excellent mechanical properties even in contact with an antifreeze liquid. Although the properties and dimensional stability can be exhibited, on the other hand, there is a problem that molding workability is remarkably impaired due to its high melting point, and as it is, it is not sufficient to produce a practical molded product with high productivity.

Further, JP-A-61-283553 describes that impact resistance is improved by blending a modified polyolefin with the above-mentioned high melting point copolyamide resin. Although the technique certainly improves the impact resistance to some extent, the initial rigidity is low, and it is not possible to suppress the decrease in rigidity particularly after long-term use under a high-humidity use environment.

[0007]

SUMMARY OF THE INVENTION As described above, in the conventional technique, there is little decrease in rigidity in a high humidity atmosphere, and
A polyamide resin or a polyamide resin that has high chemical resistance with little deterioration in material properties even under long-term contact with high-temperature automobile engine cooling water, and that has excellent heat resistance, toughness, and moldability is used. It was difficult to obtain the composition.

Therefore, the present invention is excellent in mechanical properties, heat resistance, moldability, and dimensional stability, has a small decrease in rigidity even when used for a long time in a high humidity atmosphere, has excellent durability, and has a dimensional change due to water absorption. Polyamide resin and resin composition suitable for the production of automobile harness connector molded products having a small size, especially having a thin portion, and further having high chemical resistance with little deterioration in material properties even under long-term contact with automobile engine cooling water. However, it is an object of the present invention to obtain a polyamide resin composition which is preferably used for parts such as radiator tank parts and water pump parts used in contact with cooling water in automobile engine rooms.

[0009]

That is, the present invention is as follows. "(A) Hexamethylene terephthalamide unit 55
˜5 mol%, (b) hexamethylene naphthamide unit 5
5 to 5 mol% and 70 to 0 mol% of at least one structural unit selected from (c) undecane amide unit, dodecane amide unit and caproamide unit, and (d) equimolar amount of aliphatic dicarboxylic acid and aliphatic diamine An aliphatic polyamide unit derived from a salt and an amide group 1
The number of carbon atoms per unit (amide group concentration) is 8 or more and comprises 60 to 0 mol% of polyamide units (however, the total amount of the components (c) and (d) is at least 20 mol% or more), and A polyamide resin having the following characteristics. (A) Melting point: 250 ° C. or higher and lower than 290 ° C. (b) At least one peak among the peak values of loss elastic moduli of which the glass transition point at the time of saturated water absorption is 25 ° C. or higher, which is determined by viscoelasticity measurement. Position is 80 ℃
that's all. , 2. "(A) Hexamethylene terephthalamide unit 55
˜5 mol%, (b) hexamethylene naphthamide unit 5
5 to 5 mol% and 70 to 0 mol% of at least one structural unit selected from (c) undecane amide unit, dodecane amide unit and caproamide unit, and (d) equimolar amount of aliphatic dicarboxylic acid and aliphatic diamine An aliphatic polyamide unit derived from a salt and an amide group 1
Consisting of 60 to 0 mol% of polyamide units having 8 or more carbon atoms (amide group concentration) per unit (provided that (c)
The total amount of the component and the component (d) is at least 20 mol% or more), and the characteristics thereof are in the following ranges, and a polyamide resin for a connector. (A) Melting point: 250 ° C. or higher and lower than 290 ° C. (b) At least one peak among the peak values of loss elastic moduli of which the glass transition point at the time of saturated water absorption is 25 ° C. or higher, which is determined by viscoelasticity measurement. Position is 80 ℃
that's all. ], 3. 3. The above-mentioned polyamide resin in which the hexamethylenenaphthamide unit of the component (b) is a unit derived from hexamethylenediamine and 2,6-naphthalenedicarboxylic acid. 4. The above-mentioned polyamide resin in which the structural unit of the component (c) is a caproamide unit and the proportion thereof is 1 to 70 mol%. 5. The above-mentioned polyamide resin in which the structural unit of the component (c) is a dodecane amide unit and the proportion thereof is 1 to 70 mol%. "The aliphatic polyamide unit of the component (d) is a hexamethylene sebacamide unit, and the proportion thereof is 1 to 60.
The above-mentioned polyamide resin which is a mol%. ",

7. "(A) (a) hexamethylene terephthalamide unit 55 to 5 mol%, (b) hexamethylene naphthamide unit 55 to 5 mol% and (c) undecane amide unit, dodecane amide unit and capro amide unit. At least one structural unit 70-
0 mol% and (d) carbon atoms per amide group (amide group concentration) in an aliphatic polyamide unit derived from an equimolar salt of an aliphatic dicarboxylic acid and an aliphatic diamine
A polyamide resin 99 comprising 60 to 0 mol% of a polyamide unit having a ratio of 8 or more (however, the total amount of the component (c) and the component (d) is at least 20 mol% or more), and the properties thereof are within the following ranges. A polyamide resin composition for a connector comprising -80% by weight and (B) a modified polyolefin modified with a carboxylic acid and / or a derivative thereof in an amount of 1 to 20% by weight. (A) Melting point: 250 ° C. or higher and lower than 290 ° C. (b) At least one peak among the peak values of loss elastic moduli of which the glass transition point at the time of saturated water absorption is 25 ° C. or higher, which is determined by viscoelasticity measurement. Position is 80 ℃
that's all. ], 8. “(B) Component modified polyolefin has an α-olefin homopolymer containing at least one selected from a carboxylic acid group, a carboxylic acid anhydride group, a carboxylic acid ester group, and a carboxylic acid metal base in the polymer molecular chain. Or the above-mentioned polyamide resin composition for a connector, which is a copolymer. ”, 9. 10. The above-mentioned polyamide resin composition for a connector, wherein the hexamethylenenaphthoamide unit of the component (b) is a unit derived from hexamethylenediamine and 2,6-naphthalenedicarboxylic acid. 10. The above-mentioned polyamide resin composition for a connector, wherein the structural unit of the component (c) is a caproamide unit, and the proportion thereof is 1 to 70 mol%. "The above-mentioned polyamide resin composition for a connector, wherein the structural unit of the component (c) is a dodecane amide unit and the proportion thereof is 1 to 70 mol%". "The above-mentioned polyamide resin composition for a connector, wherein the aliphatic polyamide unit of the component (d) is hexamethylene sebacamide, and the proportion thereof is 1 to 60 mol%". 13. The above-mentioned polyamide resin composition for a connector, wherein the connector is an automobile connector. "A connector obtained by injection-molding the polyamide resin described above or the polyamide resin composition described above.",

15. "(A) (a) hexamethylene terephthalamide unit 55 to 5 mol%, (b) hexamethylene naphthamide unit 55 to 5 mol% and (c) undecane amide unit, dodecane amide unit and capro amide unit. At least one structural unit 70
To 0 mol% and (d) an aliphatic polyamide unit derived from an equimolar salt of an aliphatic dicarboxylic acid and an aliphatic diamine, and having 8 or more carbon atoms per amide group (amide group concentration) A unit comprising 60 to 0 mol% (however, the total amount of the component (c) and the component (d) is at least 20 mol% or more), and 100 parts by weight of a polyamide resin whose characteristics are within the following ranges and (C) A polyamide resin composition for engine cooling water system parts, comprising 20 to 150 parts by weight of an inorganic filler. (A) Melting point: 250 ° C. or higher and lower than 290 ° C. (b) At least one peak among the peak values of loss elastic moduli of which the glass transition point at the time of saturated water absorption is 25 ° C. or higher, which is determined by viscoelasticity measurement. Position is 80 ℃
that's all. ], 16. “(A) The polyamide resin composition for engine cooling water system parts, wherein the polyamide resin further satisfies the following requirements. (C) Treatment at 130 ° C./300 hours is performed in contact with an automobile antifreeze. 85% retention of relative polymer viscosity
Or more "17. 18. The above-mentioned polyamide resin composition for engine cooling water system parts, wherein the inorganic filler of component (C) is glass fiber. 19. The above-mentioned polyamide resin composition for engine cooling water system parts, wherein the added amount of (C) glass fiber is 20 to 150 parts by weight with respect to 100 parts by weight of the polyamide resin of component (A). "The above-mentioned polyamide resin composition for engine cooling water system parts, wherein the hexamethylenenaphthoamide unit of component (b) is a unit derived from hexamethylenediamine and 2,6-naphthalenedicarboxylic acid.", 20. 21. The polyamide resin composition for engine cooling water system parts as described above, wherein the structural unit of the component (c) is a caproamide unit, and the proportion thereof is 1 to 70 mol%. 22. "A polyamide resin composition for engine cooling water system parts as described above, wherein the structural unit of the component (c) is a dodecane amide unit, and the proportion thereof is 1 to 70 mol%." 23. "A polyamide resin composition for engine cooling water system parts as described above, wherein the aliphatic polyamide unit of the component (d) is hexamethylene sebacamide, and the proportion thereof is 1 to 60 mol%.", 23. 24. "A polyamide resin composition for engine cooling water system parts as described above, wherein the engine cooling water system parts are automobile engine cooling water system parts". "Engine cooling water system parts obtained by melt-molding the polyamide resin composition according to any one of the above."

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The hexamethylene terephthalamide unit of the component (a) constituting the polyamide resin of the present invention is a unit synthesized from hexamethylene diamine and terephthalic acid or its derivative such as ester or acid halide. .

The hexamethylenenaphthoamide unit as the component (b) is a unit synthesized from hexamethylenediamine and a derivative of naphthalenedicarboxylic acid or its ester, acid halide or the like. Specific examples of naphthalenedicarboxylic acid are: , 4-naphthalenedicarboxylic acid,
1,5-naphthalenedicarboxylic acid, 1,6-naphthalenedicarboxylic acid, 1,7-naphthalenedicarboxylic acid, 2,
Examples thereof include 6-naphthalenedicarboxylic acid and 2,7-naphthalenedicarboxylic acid. Of these naphthalenedicarboxylic acids, 2,6-naphthalenedicarboxylic acid,
2,7-naphthalenedicarboxylic acid is preferably used.

Component (c) is 12-aminododecanoic acid, ω
A unit derived from raw materials such as laurolactam, 11-aminoundecanoic acid, ε-aminocaproic acid and ε-caprolactam. (D) A raw material which gives an aliphatic polyamide unit derived from an equimolar salt of an aliphatic dicarboxylic acid and an aliphatic diamine and has a carbon atom number (amide group concentration) per amide group of 8 or more. Specific examples thereof include hexamethylene diammonium sebacate, hexamethylene diammonium decanoate, hexamethylene diammonium undecanoate, and hexamethylene diammonium dodecanoate.

Each of these components (a) to (d) is
5, 55-5, 70-0, 60-0 mol%, preferably 50-30, 40-20, 40-1, 30-, respectively.
It must be a copolymer containing 1 mol% (however,
The total amount of the components (c) and (d) is at least 20 mol% or more) is necessary and important in the present invention. Because the copolymerized polyamide obtained by polymerizing the above specific copolymerization component in a very limited range of the copolymerization ratio has a specific melting point, viscoelastic behavior, and viscoelastic behavior when absorbing water, and is used as an automotive connector. This is because when used, there is little decrease in rigidity in a high-humidity atmosphere, and favorable performance such as excellent balance between heat resistance, toughness, and moldability can be exhibited. In particular, it is important that the glass transition point of 25 ° C. or higher is maintained during water absorption and that there is a segment having a loss elastic modulus peak of 80 ° C. or higher.

When the copolymerization amount of the components (a) and (b) is more than the above range, the polyamide resin produced has a high melting point (for example, more than 290 ° C.), and deterioration in melting becomes apparent, resulting in molding processability. If it is less than the above range, on the other hand, the viscoelastic properties at the time of water absorption are deteriorated, which is not preferable. If the copolymerization amount of the components (c) and (d) is larger than the above range, the melting point is lowered and the required heat resistance cannot be maintained, which is not preferable. It is not preferable because it lowers the fluidity.

The degree of polymerization of the polyamide resin of the present invention is not particularly limited, but the relative viscosity when measured at 25 ° C. in a 1% concentrated sulfuric acid solution is usually from the viewpoint of mechanical properties and moldability. 1.5-5.0, preferably 1.8-
Those in the range of 3.5, particularly preferably 2.0 to 2.8 are suitable.

The method for producing the polyamide resin of the present invention is not particularly limited, but a usual pressure melt polymerization such as hexamethylene diammonium terephthalate (6T salt) is used.
15-30 kg of a mixed aqueous solution of hexamethylenediamine, naphthalenedicarboxylic acid and ε-caprolactam
A conventional melt polymerization method in which a reaction is carried out under a steam pressure of / cm ² and then melt polymerization is carried out while releasing water in the system, or a raw material aqueous solution is heated at 150 to 320 ° C. to prepare a prepolymer once, Examples thereof include a method of solid-state polymerization at a temperature below the melting point, a method of increasing the degree of polymerization by a melt extruder, and the like. Among them, the pressure melt polymerization method is simple and suitable.

Further, the polyamide resin of the present invention may be added with additives such as a viscosity modifier, a pigment, an anti-coloring agent and a heat-resistant agent as long as the characteristics thereof are not impaired.

In the present invention, (B) a modified polyolefin modified with a carboxylic acid and / or a derivative thereof, which is appropriately used as necessary for further improvement of properties, is a functional group having an affinity for a polyamide resin. A polyolefin contained in its molecule, particularly a homopolymer of α-olefin containing at least one selected from a carboxylic acid group, a carboxylic acid anhydride group, a carboxylic acid ester group, and a carboxylic acid metal base in the polymer molecular chain. Polymers or copolymers are preferred.

Specific examples of the α-olefin homopolymers or copolymers include homopolymers such as polyethylene, polypropylene, polybutene-1, polypentene-1, polymethylpentene, ethylene, propylene, butene-1, pentene-1, 4 -Methylpentene-
1, α-olefins such as isobutylene, 1,4-hexadiene dicyclopentadiene, 2,5-norbornadiene, 5-ethylidene norbornene, 5-ethyl-2,
5-norbornadiene, 5- (1'-probenyl) -2
-A polyolefin obtained by radical polymerization of at least one non-conjugated diene such as norbornene can be mentioned.

Further, the diene elastomer is an AB type or ABAA 'type block copolymer elastic body composed of a vinyl aromatic hydrocarbon and a conjugated diene, and the end blocks A and A'are Examples thereof include thermoplastic homopolymers or copolymers derived from vinyl-based aromatic hydrocarbons, which may be the same or different and whose aromatic moiety may be monocyclic or polycyclic, such vinyl-based aromatic hydrocarbons. Examples include styrene, α-methylstyrene, vinyltoluene,
Examples thereof include vinyl xylene, ethyl vinyl xylene, vinyl naphthalene and a mixture thereof. The intermediate polymer block B is composed of a conjugated diene hydrocarbon, and examples thereof include polymers derived from 1,3-butadiene, 2,3-dimethylbutadiene, isoprene, 1,3-pentadiene and a mixture thereof. In the present invention,
Those in which the intermediate polymer block B of the above block copolymer is subjected to hydrogenation treatment are also included.

Specific examples of polyolefin copolymers include ethylene / propylene copolymers, ethylene / butene-1 copolymers, ethylene / propylene / dicyclopentadiene copolymers, ethylene / propylene / 5-ethylidene-2-norbornene copolymers. Polymer, unhydrogenated or hydrogenated polybutadiene, unhydrogenated or hydrogenated styrene / isoprene /
Examples thereof include styrene triblock copolymers, unhydrogenated or hydrogenated styrene / butadiene / styrene triblock copolymers, and the like.

As functional groups for modifying these polyolefins, carboxylic acid groups, carboxylic acid anhydride groups, carboxylic acid ester groups, carboxylic acid metal base carboxylic acid imide groups,
Carboxylic acid amide groups and the like, and examples of compounds containing these functional groups include acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, crotonic acid,
Methyl maleic acid, methyl fumaric acid, mesaconic acid, citraconic acid, glutaconic acid and metal salts of these carboxylic acids, methyl hydrogen maleate, methyl hydrogen itaconic acid, methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate , Hydroxyethyl acrylate, methyl methacrylate, methacrylic acid 2
-Ethylhexyl, hydroxyethyl methacrylate,
Aminoethyl methacrylate, dimethyl maleate, dimethyl itaconic acid, maleic anhydride, itaconic anhydride,
Citraconic anhydride, Endobicyclo- (2,2,1)-
5-heptene-2,3-dicarboxylic acid, endobicyclo- (2,2,1) -5-heptene-2,3-dicarboxylic acid anhydride, maleimide, N-ethylmaleimide, N-butylmaleimide, N-phenyl Examples thereof include maleimide, glycidyl acrylate, glycidyl methacrylate, glycidyl ethacrylate, glycidyl itaconate and glycidyl citracone.

The method of introducing these functional group-containing components is not particularly limited, and a method such as copolymerization or graft introduction to an unmodified polyolefin with a radical initiator can be used. The amount of the functional group-containing component introduced is appropriately in the range of 0.001 to 40 mol%, preferably 0.01 to 35 mol%, based on the whole modified polyolefin.

Specific examples of the modified polyolefin particularly useful in the present invention include maleic anhydride modified polyethylene, maleic anhydride modified polypropylene, ethylene / acrylic acid copolymers, ethylene / methacrylic acid copolymers and copolymers thereof. Some or all of carboxylic acid moieties are salts with sodium, lithium, potassium, zinc, calcium, ethylene / methyl acrylate copolymer, ethylene / ethyl acrylate copolymer, ethylene / methyl methacrylate copolymer Copolymer, ethylene / ethyl methacrylate copolymer, ethylene / ethyl acrylate-g-maleic anhydride copolymer, ("g" represents a graft, the same applies hereinafter), ethylene / methyl methacrylate-g-maleic anhydride Copolymer, ethylene / ethyl acrylate-g-maleimide copolymer, Styrene / ethyl acrylate -g-N
-Phenylmaleimide copolymer and partially saponified products of these copolymers, ethylene / glycidyl methacrylate copolymer, ethylene / vinyl acetate / glycidyl methacrylate copolymer, ethylene / methyl methacrylate /
Glycidyl methacrylate copolymer, ethylene / glycidyl acrylate copolymer, ethylene / vinyl acetate / glycidyl acrylate copolymer, ethylene / glycidyl ether copolymer, ethylene / propylene-g-
Maleic anhydride copolymer, ethylene / butene-1-g-
Maleic anhydride copolymer, ethylene / propylene / 1,
4-hexadiene-g-maleic anhydride copolymer, ethylene / propylene / dicyclopentadiene-g-maleic anhydride copolymer, ethylene / propylene / 2,5-norbornadiene-g-maleic anhydride copolymer, ethylene / Propylene-g-N-phenylmaleimide copolymer, ethylene / butene-1-g-N-phenylmaleimide copolymer, hydrogenated styrene / butadiene / styrene-g
-Maleic anhydride copolymer, hydrogenated styrene / isoprene / styrene-g-maleic anhydride copolymer, ethylene /
Propylene-g-glycidyl methacrylate copolymer, ethylene / butene-1-g-glycidyl methacrylate copolymer, ethylene / propylene / 1,4-hexadiene-
Examples thereof include g-glycidyl methacrylate copolymer, ethylene / propylene / dicyclopentadiene-g-glycidyl methacrylate copolymer, hydrogenated styrene / butadiene / styrene-g-glycidyl methacrylate copolymer and the like.

In the present invention, the content of the modified polyolefin as the component (B) is in the range of 1 to 20% by weight, and the preferable range is 3 to 10% by weight.

Among the polyamide resin compositions of the present invention,
Examples of the inorganic filler used as the component (C) include fibrous / non-fibrous inorganic reinforcing materials, and specific examples of the reinforcing materials include glass fiber, carbon fiber, potassium titanate whisker, zinc oxide whisker, Fibrous fillers such as aluminum borate whiskers, aramid fibers, alumina fibers, silicon carbide fibers, ceramic fibers, asbestos fibers, gypsum fibers, and metal fibers, wollastonite, zeolite, sericite, kaolin, mica, clay, pyrophyllite , Bentonite, asbestos, talc, silicates such as alumina silicate, alumina, silicon oxide, magnesium oxide, zirconium oxide, titanium oxide, metal compounds such as iron oxide, calcium carbonate, magnesium carbonate, carbonates such as dolomite, calcium sulfate, Sulfates such as barium sulfate, hydroxide Neshiumu, calcium hydroxide,
Non-fibrous fillers such as hydroxides such as aluminum hydroxide, glass beads, ceramic beads, boron nitride, silicon carbide and silica may be mentioned, and these may be hollow, and two types of these fillers may be used. The above can be used together. Among these fillers, glass fiber is particularly preferably used in the present invention.

The glass fiber is a glass fiber having an average fiber diameter of 5 to 15 μm, and its fiber length is not particularly limited. Usually, a glass fiber having a strand length of 3 mm, which has a high extrusion kneading workability, can be used, but a glass fiber having a strand length of 1 mm or more and a glass fiber having a fiber length of 20 to 500 μm can also be used as a raw material as a mixture. When two or more kinds of glass fibers having different strand lengths are used in combination, it is also preferable to use glass fibers having different average diameters of 2 μm or more.

The content of the filler in the resin composition of the present invention is in the range of 20 to 150 parts by weight, preferably 25 to 100 parts by weight, and more preferably 4 to 100 parts by weight of the nylon resin.
The range of 5 to 80 parts by weight is more preferable.

In addition, these fillers are used as isocyanate compounds, organic silane compounds, organic titanate compounds,
Pretreatment with a coupling agent such as an organic borane compound or an epoxy compound before use is preferable in terms of obtaining more excellent mechanical strength.

The addition of an alkoxysilane having at least one functional group selected from the group consisting of epoxy group, amino group, isocyanate group, hydroxyl group, mercapto group and ureido group to the nylon resin composition of the present invention is mechanical Strength,
Effective in improving toughness.

Specific examples of such compounds include epoxy groups such as γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane and the like. Containing alkoxysilane compound, γ-mercaptopropyltrimethoxysilane, mercapto group-containing alkoxysilane compound such as γ-mercaptopropyltriethoxysilane, γ-ureidopropyltriethoxysilane, γ-ureidopropyltrimethoxysilane, γ
An ureido group-containing alkoxysilane compound such as-(2-ureidoethyl) aminopropyltrimethoxysilane,
γ-isocyanatopropyltriethoxysilane, γ-isocyanatopropyltrimethoxysilane, γ-isocyanatopropylmethyldimethoxysilane, γ-isocyanatopropylmethyldiethoxysilane, γ-isocyanatopropylethyldimethoxysilane, γ-isocyanato Propylethyldiethoxysilane, isocyanato group-containing alkoxysilane compounds such as γ-isocyanatopropyltrichlorosilane, γ- (2-aminoethyl) aminopropylmethyldimethoxysilane, γ- (2-aminoethyl) aminopropyltrimethoxysilane, Amino group-containing alkoxysilane compound such as γ-aminopropyltrimethoxysilane, hydroxyl group-containing alkoxy such as γ-hydroxypropyltrimethoxysilane and γ-hydroxypropyltriethoxysilane And the like, such as orchids compound.

Further, in the nylon resin composition of the present invention, talc, kaolin, organic phosphorus compounds, crystal nucleating agents such as polyether ether ketone, anti-coloring agents such as hypophosphite, hindered phenols, hindered amines, etc. Additives such as antioxidants, heat stabilizers, lubricants, anti-UV agents, coloring agents and antistatic agents can be added.

The method for preparing the nylon resin composition of the present invention is not limited to a specific method, but as a concrete and efficient example, a mixture of a raw material nylon resin and a filler such as glass fiber is uniaxially or biaxially mixed. It is supplied to a known melt-kneader such as an extruder, a Banbury mixer, a kneader, and a mixing roll, and is 2 depending on the melting point of the nylon resin used.
Examples thereof include a method of melt-kneading at a temperature of 50 to 330 ° C.

The polyamide resin composition obtained here contains antioxidants, heat stabilizers such as copper iodide and potassium iodide, lubricants, crystal nucleating agents, etc. within the range of not impairing the properties thereof.
Usual additives such as UV inhibitors, colorants, flame retardants and small amounts of other polymers can be added.

The method for producing the present composition is not particularly limited, and the polyamide resin, modified polyolefin and other additives of the present invention are dry blended by using a ribbon blender, a Henschel mixer, a V blender, etc., and then a Banbury mixer, mixing. Examples of the method include melt kneading using a roll, a single-screw or twin-screw extruder, a kneader, and the like. Of these, a typical method is melt kneading using a single-screw or twin-screw extruder having a sufficient kneading force.

The polyamide resin and the resin composition obtained by the present invention are excellent in mechanical properties, heat resistance, moldability and dimensional stability, and have a small decrease in rigidity even when used for a long time in a high humidity atmosphere, and are durable. Excellent in heat resistance and chemical resistance, small in size change due to water absorption, and molded parts for automobile harness connector with thin wall parts and automobile engine cooling water system parts, especially radiator tank parts such as radiator tank top and base, coolant reserve tank, water Suitable for manufacturing parts used in contact with cooling water in automobile engine rooms, such as water pump parts such as pipes, water pump housings, water pump impellers, valves, etc., and the resulting molded products have high practical value. It is a thing.

[0039]

EXAMPLES The effects of the present invention will be further described below with reference to examples, but the present invention is not limited to these examples. The properties described in Examples and Comparative Examples were measured by the following methods.

Melting point: RD manufactured by Seiko Denshi Kogyo Co., Ltd.
Using a C220 type differential operation calorimeter, the temperature was once raised at a temperature rising rate of 20 ° C./min, held at the endothermic peak plus 20 ° C. for 5 minutes, and then lowered to 100 ° C. at a rate of 20 ° C./min and held for 5 minutes Then, the endothermic peak when the temperature was raised at a heating rate of 20 ° C. was taken as the melting point. -Viscoelastic behavior: A polyamide resin sample was melt-press molded to form a sheet having a thickness of about 0.2 mm, and a 2 x 50 mm strip-shaped test piece was cut out from the Leo Vibron DDV-II-EA manufactured by Toyo Baldwin. Was used under the conditions of a frequency of 110 Hz and a heating rate of 2 ° C./min. The peak temperature of the loss elastic modulus corresponding to α-dispersion was taken as the glass transition point. In addition, the peak temperature of the highest temperature side of the loss elastic coefficient observed by specific splitting during water absorption is shown as the high temperature side peak during water absorption.

Tensile strength: ASTMD638 Bending elastic modulus: According to ASTMD790, the bending elastic modulus was measured in absolutely dry condition and at the time of atmospheric equilibrium water absorption.

-Practical water absorption characteristics: The connector shown in Fig. 1 having a maximum value of 55 mm, a height of 13 mm, a depth of 37 mm and a thickness of 1 mm was molded by injection molding.
After placing as in (B) and placing a weight of 50 g thereon, the degree of deformation of the molded article was observed after standing for 100 hours at 30 ° C. and 95% RH. The criteria are as follows. ○: No deformation △: Small deformation X: Large deformation

Example 1 Hexamethylenediammonium terephthalate (6T salt) and hexamethylenedianne prepared so that the hexamethylene terephthalamide unit was 40 mol%, the hexamethylene naphthamide unit was 30 mol%, and the caproamide unit was 30 mol%. And a mixed aqueous solution of an equimolar salt of 2,6-naphthalenedicarboxylic acid (6N salt) and ε-caprolactam (solid raw material concentration 60% by weight)
Was charged into a pressure polymerization vessel, heated with stirring, and the water vapor pressure was adjusted to 19
After reacting at kg / cm ² for 1.5 hours, the pressure was gradually released over about 2 hours, and the reaction was further performed for about 30 minutes under a normal pressure nitrogen stream.
At this time, the temperature inside the final polymerization vessel was 300 ° C. After the reaction is completed, the generated polymer is discharged from the discharge port at the bottom of the polymerization vessel,
It was cooled in a cooling bath and pelletized.

The polyamide resin obtained here had a relative viscosity of 2.45 and its characteristics were as shown in Table 1.
This polyamide resin is injection molded to obtain various test pieces,
When the characteristics were measured, as shown in Table 1, it was found that they have excellent rigidity and dimensional stability even when absorbing water, and are useful as a material for injection molded articles.

Comparative Example 1 Hexamethylene terephthalamide unit 30 mol%, hexamethylene adipamide unit 7
A mixed aqueous solution of hexamethylene diammonium terephthalate (6T salt) and hexamethylene diammonium adipate (AH salt) (60% by weight of solid raw material) prepared so as to be 0 mol% was charged in a pressure polymerization vessel, and Polymerization, molding and characteristic evaluation were performed in exactly the same manner. The results are shown in Table 1, and the polyamide resin obtained here has a low rigidity especially when absorbing water and cannot withstand practical use.

[Comparative Example 2] Example 2 was carried out except that the mixing ratio of the raw materials was changed so that the composition of the resulting polyamide was 10 mol% of hexamethylene terephthalamide units, 10 mol% of hexamethylene naphthamide units, and 80 mol% of caproamide units. Polymerization, molding and property evaluation were performed in exactly the same manner as in Example 1. The results are shown in Table 1. The polyamide resin obtained here also has low rigidity when absorbing water and cannot be used practically.

[Examples 2 and 3] Polymerization, molding and property evaluation were carried out in the same procedure as in Example 1 except that the mixing ratio of the raw materials was changed so that the polyamide resin produced had the composition shown in Table 1. It was The results are as shown in Table 1, and the polyamide resin obtained here was also excellent in rigidity and dimensional stability when absorbing water.

[0048]

[Table 1]

[Examples 4 to 6] The polyamide resin obtained in Examples 1 to 3 and the polyethylene and / or polypropylene modified with maleic anhydride were used in a mixing ratio shown in Table 2 by using a twin-screw extruder. After melt-kneading, injection molding and characteristic evaluation were sequentially performed. As the results are summarized in Table 2, all of the compositions had excellent properties.

[0050]

[Table 2]

[Examples 7 to 11] The polyamide resins and glass fibers obtained in Examples 1 to 3 were dry blended at the compounding ratio shown in Table 3 and then fed to the hopper of a 40 mmφ single screw extruder. Cylinder temperature 270 ~ 310 ℃,
Melt-kneading was performed under the conditions of a screw rotation speed of 100 rpm to obtain a glass fiber reinforced composition. This composition was injection-molded to obtain various test pieces, and predetermined characteristics were evaluated. The results are summarized in Table 3. Each of the compositions of the present invention was a composition having excellent properties such as high antifreeze resistance.

[Comparative Examples 3 and 4] The polyamide resin obtained in Comparative Examples 1 and 2 and the glass fiber were dry blended at a compounding ratio shown in Table 3, and then melt-kneaded in the same manner as in Examples 7 to 9. Then, a glass fiber reinforced composition was obtained. This composition was injection-molded to obtain various test pieces, and predetermined characteristics were evaluated. The results are shown in Table 3, and the polyamide resin obtained here had a particularly low antifreeze resistance and could not be put to practical use.

[0053]

[Table 3]

[0054]

EFFECT OF THE INVENTION The polyamide resin and resin composition obtained by the present invention have excellent mechanical properties, heat resistance, moldability, and dimensional stability, and have little decrease in rigidity even when used for a long time in a high humidity atmosphere. , Excellent in durability and chemical resistance, small in size change due to absorption of water, and molded parts for automobile harness connector with thin wall parts and automobile engine cooling water system parts, especially radiator tank parts such as radiator tank top and base, coolant reserve tank , Water pipes, water pump housings, water pump impellers, valves and other water pump parts, which are suitable for manufacturing parts used in contact with cooling water in the automobile engine room, and the resulting molded products have practical value. It is expensive.

[Brief description of drawings]

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

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI // (C08L 77/00 C08L 23:26 23:26) (72) Inventor Kazuhiko Kobayashi 9 Oe-cho, Minato-ku, Nagoya-shi, Aichi No. 1 Toray Co., Ltd. Nagoya Business Site (56) Reference JP-A-5-105753 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) C08G 69/00-69/50 C08L 77 / 00-77/12

Claims (24)

(57) [Claims] 1. (a) Hexamethylene terephthalamide unit 55 to 5 mol%, (b) Hexamethylene naphthamide unit 55 to 5 mol%, (c) Undecane amide unit,
70 to 0 mol% of at least one structural unit selected from dodecane amide units and caproamide units, and (d) an aliphatic polyamide unit derived from an equimolar salt of an aliphatic dicarboxylic acid and an aliphatic diamine, and an amide Consists of 60 to 0 mol% of a polyamide unit having 8 or more carbon atoms (amide group concentration) per group (however,
The total amount of the components (c) and (d) is at least 20 mol% or more), and the characteristics thereof are in the following ranges. (A) Melting point: 250 ° C. or higher and lower than 290 ° C. (b) At least one peak among the peak values of loss elastic moduli of which the glass transition point at the time of saturated water absorption is 25 ° C. or higher, which is determined by viscoelasticity measurement. Position is 80 ℃
that's all. 2. An (a) hexamethylene terephthalamide unit (55 to 5 mol%), (b) hexamethylene naphthamide unit (55 to 5 mol%), (c) an undecane amide unit,
70 to 0 mol% of at least one structural unit selected from dodecane amide units and caproamide units, and (d) an aliphatic polyamide unit derived from an equimolar salt of an aliphatic dicarboxylic acid and an aliphatic diamine, and an amide Consists of 60 to 0 mol% of a polyamide unit having 8 or more carbon atoms (amide group concentration) per group (however,
The total amount of the components (c) and (d) is at least 20 mol% or more), and the characteristics thereof are in the following ranges. (A) Melting point: 250 ° C. or higher and lower than 290 ° C. (b) At least one peak among the peak values of loss elastic moduli of which the glass transition point at the time of saturated water absorption is 25 ° C. or higher, which is determined by viscoelasticity measurement. Position is 80 ℃
that's all. 3. The polyamide resin according to claim 1, wherein the hexamethylenenaphthamide unit as the component (b) is a unit derived from hexamethylenediamine and 2,6-naphthalenedicarboxylic acid. 4. The polyamide resin according to claim 1, wherein the structural unit of the component (c) is a caproamide unit, and the proportion thereof is 1 to 70 mol%. 5. The polyamide resin according to claim 1, wherein the structural unit of the component (c) is a dodecane amide unit, and the proportion thereof is 1 to 70 mol%. 6. The polyamide resin according to claim 1, wherein the aliphatic polyamide unit as the component (d) is a hexamethylene sebacamide unit, and the proportion thereof is 1 to 60 mol%. . 7. (A) (a) hexamethylene terephthalamide unit 55 to 5 mol%, (b) hexamethylene naphthamide unit 55 to 5 mol%, (c) undecane amide unit, dodecane amide unit and caproamide unit 70 to 0 mol% of at least one structural unit selected from the group, and (d) an aliphatic polyamide unit derived from an equimolar salt of an aliphatic dicarboxylic acid and an aliphatic diamine, and carbon atoms per amide group Number (amide group concentration) is 8
The polyamide unit is 60 to 0 mol% as described above (provided that the total amount of the components (c) and (d) is at least 20).
Polyamide resin for connectors comprising 99 to 80% by weight of a polyamide resin having the following characteristics, and (B) 1 to 20% by weight of a modified polyolefin modified with a carboxylic acid and / or a derivative thereof. Composition. (A) Melting point: 250 ° C. or higher and lower than 290 ° C. (b) At least one peak among the peak values of loss elastic moduli of which the glass transition point at the time of saturated water absorption is 25 ° C. or higher, which is determined by viscoelasticity measurement. Position is 80 ℃
that's all. 8. The modified polyolefin as the component (B) is at least one selected from a carboxylic acid group, a carboxylic acid anhydride group, a carboxylic acid ester group, and a carboxylic acid metal base.
The polyamide resin composition for a connector according to claim 7, which is a homopolymer or copolymer of α-olefin containing a seed in the polymer molecular chain. 9. The polyamide resin composition for a connector according to claim 7, wherein the hexamethylenenaphthamide unit as the component (b) is a unit derived from hexamethylenediamine and 2,6-naphthalenedicarboxylic acid. 10. The polyamide resin composition for a connector according to claim 7, wherein the structural unit of the component (c) is a caproamide unit, and the proportion thereof is 1 to 70 mol%. 11. The polyamide resin composition for a connector according to claim 7, wherein the structural unit of the component (c) is a dodecane amide unit, and the proportion thereof is 1 to 70 mol%. 12. The aliphatic polyamide unit of the component (d) is hexamethylene sebacamide, and the ratio thereof is 1.
It is -60 mol%, The polyamide resin for connectors according to any one of claims 7 to 11. 13. The polyamide resin composition for a connector according to claim 7, wherein the connector is an automobile connector. 14. A connector obtained by injection molding the polyamide resin according to any one of claims 1 to 6 or the polyamide resin composition according to any one of claims 7 to 13. 15. (A) (a) hexamethylene terephthalamide unit 55 to 5 mol%, (b) hexamethylene naphthamide unit 55 to 5 mol%, (c) undecane amide unit, dodecane amide unit and caproamide unit 70 to 0 mol% of at least one structural unit selected from the group, and (d) an aliphatic polyamide unit derived from an equimolar salt of an aliphatic dicarboxylic acid and an aliphatic diamine, and carbon atoms per amide group Number (amide group concentration) is 8
The polyamide unit is 60 to 0 mol% as described above (provided that the total amount of the components (c) and (d) is at least 20).
100% by weight of a polyamide resin having the following characteristics, and (C) an inorganic filler 20:
A polyamide resin composition for engine cooling water system parts, comprising about 150 parts by weight. (A) Melting point: 250 ° C. or higher and lower than 290 ° C. (b) At least one peak among the peak values of loss elastic moduli of which the glass transition point at the time of saturated water absorption is 25 ° C. or higher, which is determined by viscoelasticity measurement. Position is 80 ℃
that's all. 16. The polyamide resin composition for engine cooling water system parts according to claim 15, wherein the polyamide resin (A) further satisfies the following requirements. (C) The retention rate of the relative viscosity of the polymer is 85% when the treatment is carried out at 130 ° C./300 hours under the contact with the automobile antifreeze.
that's all 17. The polyamide resin composition for engine cooling water system parts according to claim 15, wherein the inorganic filler as the component (C) is glass fiber. 18. The amount of (C) glass fiber added is (A)
25 to 100 relative to 100 parts by weight of the component polyamide resin
The polyamide resin composition for engine cooling water system parts according to claim 17, which is parts by weight. 19. The hexamethylenenaphthamide unit of component (b) is a unit derived from hexamethylenediamine and 2,6-naphthalenedicarboxylic acid.
18. A polyamide resin composition for engine cooling water system parts according to any one of 18 above. 20. The polyamide resin composition for engine cooling water system parts according to claim 15, wherein the structural unit of the component (c) is a caproamide unit, and the proportion thereof is 1 to 70 mol%. 21. The polyamide resin composition for engine cooling water system parts according to claim 15, wherein the structural unit of the component (c) is a dodecane amide unit, and the proportion thereof is 1 to 70 mol%. . 22. The aliphatic polyamide unit as the component (d) is hexamethylene sebacamide, and the ratio thereof is 1.
It is -60 mol%, The polyamide resin composition for engine cooling water system parts in any one of Claims 15-21. 23. The polyamide resin composition for engine cooling water system parts according to claim 15, wherein the engine cooling water system parts are automobile engine cooling water system parts. 24. An engine cooling water system component obtained by melt molding the polyamide resin composition according to any one of claims 15 to 23.