JP2012017429A - Polyamide resin composition and molding comprising the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a meta-xylylene based polyamide resin based resin composition which is lighter, in which water absorption is lower, and the crystallization rate is quicker than that of a conventional meta-xylylene adipamide resin, and to provide a molding of the same.SOLUTION: The polyamide resin composition includes 15-200 pts.mass of a filler (B) based on 100 pts.mass of a polyamide resin (A) in which 30-95 mol% of a diamine constituent unit originates in meta-xylylene diamine, 70-5 mol% thereof originates in para-xylylene diamine, and at least 50 mol% of a dicarboxylic acid constituent unit originates in sebacic acid. In addition, the molding comprising the same is disclosed.

Description

  The present invention relates to a polyamide resin composition and a molded article comprising the same, and more particularly to a metaxylylene-based polyamide resin composition that is light, has a low water absorption rate, and has a high crystallization rate, and a molded article formed by molding the composition.

  Polyamide resin is an engineering plastics with excellent mechanical strength such as impact resistance, friction resistance and wear resistance, heat resistance, and oil resistance. It is an automotive part, electronic / electric equipment part, OA equipment part, machine. It is widely used in fields such as parts, building materials and housing equipment, and the field of use has expanded in recent years.

  For example, many types of polyamide resins such as polyamide 6 and polyamide 66 are known. Metaxylylene adipamide (hereinafter, also referred to as “MXD6”) obtained from metaxylylenediamine and adipic acid is used. Unlike polyamide 6, polyamide 66, etc., it has an aromatic ring in the main chain, has high rigidity, low water absorption, excellent oil resistance, and has low molding shrinkage and small shrinkage and warpage in molding. It is also suitable for precision molding and is positioned as an extremely excellent polyamide resin. For these reasons, MXD6 is a molding material in various fields such as automobile parts such as automobiles, general machine parts, precision machine parts, electronic / electric equipment parts, leisure sports equipment, civil engineering and building materials, especially for injection molding. In recent years, it has been increasingly used as a material.

However, although MXD6 has a lower water absorption rate than other polyamides such as polyamide 66, a molding material having a lower water absorption rate is required in accordance with further recent demands. Further, metaxylylene-based polyamide resins have a problem that their crystallization speed is slow, and various studies have been conducted on MXD6 (see, for example, Patent Document 1).
There is also a need for lighter and stronger polyamide resin materials. Metaxylylene sebacamide (hereinafter, also referred to as “MXD10”) obtained from metaxylenediamine and sebacic acid is a metaxylylene-based polyamide resin that is lighter than MXD6 and has a low water absorption rate.

  However, since MXD10 has a slower crystallization rate than MXD6, the above improvement method for MXD6 is not sufficient for MXD10, and the examination itself for increasing the crystallization rate of MXD10 has been made so far. Not much done. Patent Document 2 has been proposed as a prescription for improving the crystallization rate of MXD10, but it is not sufficient and further improvement has been demanded.

JP-A-51-63860 Japanese Unexamined Patent Publication No. 63-137756

  An object of the present invention is to solve the above-described problems and provide a polyamide resin composition that is lighter, has a lower water absorption rate, and has a higher crystallization speed than conventional MXD6 and MXD10, and a molded article using the same.

  As a result of intensive studies to achieve the above object, the present inventors have used a mixed diamine of a specific ratio of metaxylylenediamine and paraxylylenediamine as a diamine constituent unit, and polycondensation with a specific amount of sebacic acid. The present inventors have found that an excellent polyamide resin composition in which the above-mentioned problems are solved can be obtained by using the polyamide resin thus prepared and blending a specific amount of the filler therein, thereby completing the present invention.

  That is, according to the first invention of the present invention, 30 to 95 mol% of the diamine structural unit is derived from metaxylylenediamine, 70 to 5 mol% is derived from paraxylylenediamine, and 50 mol of the dicarboxylic acid structural unit. % Of the polyamide resin (A) derived from sebacic acid is contained in an amount of 15 to 200 parts by mass of the filler (B).

  According to the second invention of the present invention, there is provided a polyamide resin composition characterized in that, in the first invention, the moisture content of the polyamide resin (A) is 0.01 to 0.5% by mass. Provided.

  According to the third invention of the present invention, in the first or second invention, the polyamide resin composition has a moisture content of 0.01 to 0.1% by mass. Things are provided.

According to a fourth aspect of the present invention, in any one of the first to third aspects, the density of the polyamide resin (A) is 1.1 to 1.2 g / cm ^3. A polyamide resin composition is provided.

  According to a fifth invention of the present invention, in any one of the first to fourth inventions, the polyamide resin (A) has a phosphorus atom concentration of 50 to 1,000 ppm. Things are provided.

  According to a sixth invention of the present invention, in any one of the first to fifth inventions, the polyamide resin composition has a phosphorus atom concentration of 50 to 1,000 ppm. Is provided.

  According to the seventh invention of the present invention, in any one of the first to sixth inventions, the carbodiimide compound (C) is further added in an amount of 0.1 to 2 parts by mass with respect to 100 parts by mass of the polyamide resin (A). The polyamide resin composition characterized by containing a part is provided.

  According to an eighth aspect of the present invention, there is provided a polyamide resin composition according to the seventh aspect, wherein the carbodiimide compound (C) is an aliphatic or alicyclic polycarbodiimide compound. .

  According to the ninth invention of the present invention, in any one of the first to eighth inventions, the stabilizer (D) is further added in an amount of 0.01 to 1 mass with respect to 100 parts by mass of the polyamide resin (A). The polyamide resin composition characterized by containing a part is provided.

  According to a tenth aspect of the present invention, in the ninth aspect, the stabilizer (D) is selected from an inorganic, aromatic secondary amine or organic sulfur stabilizer. A polyamide resin composition is provided.

  Furthermore, according to the eleventh aspect of the present invention, there is provided a molded article formed by molding the polyamide resin composition of any one of the first to tenth aspects.

  The polyamide resin composition of the present invention is a metaxylylene-based polyamide resin-based composition that is lighter, has a lower water absorption rate, and has a higher crystallization speed than the metaxylylene adipamide resin (MXD6) material. Suitable as a material. Further, the molded product obtained from the polyamide resin composition of the present invention has no problems such as discoloration, has a sufficient degree of crystallization, and is excellent in mechanical properties such as appearance and impact resistance.

[1. Summary of the Invention]
In the polyamide resin composition of the present invention, 30 to 95 mol% of the diamine structural unit is derived from metaxylylenediamine, 70 to 5 mol% is derived from paraxylylenediamine, and 50 mol% or more of the dicarboxylic acid structural unit is sebacin. The filler (B) is contained in an amount of 15 to 200 parts by mass with respect to 100 parts by mass of the polyamide resin (A) derived from an acid.
Hereinafter, each component which comprises the polyamide resin composition of this invention is demonstrated in detail.

[2. Polyamide resin (A)]
In the polyamide resin (A) used in the present invention, 30 to 95 mol% of the structural unit derived from the diamine component is derived from metaxylylenediamine, and 70 to 5 mol% is derived from paraxylylenediamine. Moreover, 50 mol% or more of the structural unit derived from the dicarboxylic acid component is a polyamide resin derived from sebacic acid.

By adding paraxylylenediamine to metaxylylenediamine as the diamine component of the polyamide resin (A), the melting point, glass transition point, heat resistance, and crystallization speed of the polyamide resin (A) can be improved.
Further, when the constitution of the diamine component and the dicarboxylic acid component is in the above range, the water absorption of the polyamide resin (A) and the finally obtained polyamide resin composition can be optimized, and furthermore, the obtained polyamide resin The crystallization speed of the composition can be increased, the moldability such as releasability can be improved, and a molded article having a good appearance can be obtained. In addition, even if the molded product is thinned, physical properties such as the elastic modulus can be maintained, so that the molded product can be reduced in weight.

When the amount of metaxylylenediamine is less than 30 mol% in the diamine component, the appearance of the molded product is deteriorated, and when it exceeds 95 mol%, the crystallization rate is slowed. The amount of metaxylylenediamine is preferably 40 to 90 mol%, more preferably 45 to 80 mol%, still more preferably 50 to 70 mol%.
In addition, when the amount of paraxylylenediamine exceeds 70 mol% in the diamine component, the appearance of the molded article is deteriorated, and when it is less than 5 mol%, the crystallization rate becomes slow. The amount of paraxylylenediamine is preferably 60 to 10 mol%, more preferably 55 to 20 mol%, still more preferably 50 to 30 mol%.

  On the other hand, when the amount of sebacic acid is less than 50 mol% in the dicarboxylic acid component, the moisture content of the polyamide resin (A) increases, water absorption (hygroscopicity) increases, and density increases. As the amount of sebacic acid increases, the weight can be reduced. The amount of sebacic acid is preferably 60 to 100 mol%, more preferably 70 to 100 mol%.

  The polyamide resin (A) includes metaxylylenediamine and paraxylylenediamine within the above range, a diamine component containing other diamine, and a dicarboxylic acid component containing sebacic acid in the above range and containing other dicarboxylic acid. May be a copolycondensation polymer obtained by polycondensation.

  Examples of diamine components other than metaxylylenediamine and paraxylylenediamine that can be used in the production of the polyamide resin (A) include tetramethylenediamine, pentamethylenediamine, 2-methylpentanediamine, hexamethylenediamine, heptamethylenediamine, and octamethylene. Aliphatic diamines such as diamine, nonamethylenediamine, decamethylenediamine, dodecamethylenediamine, 2,2,4-trimethyl-hexamethylenediamine, 2,4,4-trimethylhexamethylenediamine; 1,3-bis (aminomethyl) ) Cyclohexane, 1,4-bis (aminomethyl) cyclohexane, 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, bis (4-aminocyclohexyl) methane, 2,2-bis (4-aminocyclohexyl) And alicyclic diamines such as propane, bis (aminomethyl) decalin and bis (aminomethyl) tricyclodecane; aromatic rings such as bis (4-aminophenyl) ether, paraphenylenediamine and bis (aminomethyl) naphthalene. Examples thereof include, but are not limited to, diamines.

As a dicarboxylic acid component other than sebacic acid that can be used in the production of the polyamide resin (A), a dicarboxylic acid component mainly composed of an α, ω-linear aliphatic dicarboxylic acid having 4 to 20 carbon atoms is preferable. For example, adipic acid And aliphatic dicarboxylic acids such as succinic acid, glutaric acid, pimelic acid, suberic acid, azelaic acid, undecanedioic acid, and dodecanedioic acid. Of these, particularly preferred dicarboxylic acid includes adipic acid. Among these, when using a dicarboxylic acid component other than sebacic acid, it is preferable to use adipic acid, undecanedioic acid, dodecanedioic acid, and the like. By using adipic acid in combination, it becomes easy to control the elastic modulus, water absorption, and crystallinity. The amount of adipic acid is more preferably 40 mol% or less, and further preferably 30 mol% or less. Moreover, it is preferable to use undecanedioic acid and dodecanedioic acid together because the specific gravity of the polyamide resin (A) is reduced and the molded product is reduced in weight.
A preferable use ratio in the case of using an α, ω-linear aliphatic dicarboxylic acid having 4 to 20 carbon atoms other than sebacic acid is less than 50 mol%, preferably 40 mol% or less.

In addition, aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, and 2,6-naphthalenedicarboxylic acid can be used, and these can be used in combination.
Furthermore, in addition to the diamine component and the dicarboxylic acid component, as a component constituting the polyamide resin (A), lactams such as ε-caprolactam and laurolactam, aminocaproic acid, aminoundecanoic acid as long as the effects of the present invention are not impaired. Aliphatic aminocarboxylic acids such as can also be used as a copolymerization component.

  Moreover, the above-mentioned polyamide resin (A) can also be used by blending one type or a plurality of resins.

The manufacturing method of a polyamide resin (A) is not specifically limited, It manufactures by a conventionally well-known method and superposition | polymerization conditions. A small amount of monoamine or monocarboxylic acid may be added as a molecular weight regulator during the polycondensation of the polyamide resin.
The polyamide resin of the present invention can be obtained by so-called solid phase polymerization in which polycondensation in a molten state or once polycondensed in a molten state to obtain a low-viscosity polyamide, followed by heat treatment in a solid state.

Although the polycondensation method in the molten state is not particularly limited, a method in which an aqueous solution of a polyamide salt of a diamine component and a dicarboxylic acid component is heated under pressure and polycondensed in a molten state while removing water and condensed water, Examples thereof include a method in which a diamine component is directly added to a dicarboxylic acid in a molten state and polycondensed in an atmosphere of atmospheric pressure or steam. In this case, in order to keep the reaction system in a uniform liquid state, the diamine component is continuously added to the molten dicarboxylic acid phase, while the reaction temperature is increased so that the reaction temperature does not fall below the melting point of the generated oligoamide and polyamide. The polycondensation proceeds while warming. Other polymerization conditions are not particularly limited, but by appropriately selecting the feed ratio of the raw dicarboxylic acid component and the diamine component, the polymerization catalyst, and the molecular weight regulator, the polymerization temperature is lowered, and the polymerization time is shortened. Polyamide resins with controlled properties, particularly thermal properties, can be produced.
Further, when it is necessary to further increase the molecular weight of the polyamide resin, it is preferable to perform solid phase polymerization. The solid phase polymerization method is not particularly limited, and can be carried out using a batch heating apparatus or the like under an inert gas atmosphere or under reduced pressure.

As a polymerization catalyst, phosphorus compounds, such as phosphoric acid, phosphorous acid, and hypophosphorous acid, those salts, and ester compounds are mentioned. Specific examples of forming salts and esters include potassium, sodium, magnesium, calcium, zinc, cobalt, manganese, tin, tungsten, vanadium, germanium, titanium, antimony and other metal salts, ammonium salts, ethyl esters, isopropyl esters, Examples thereof include butyl ester, hexyl ester, octadecyl ester, stearyl ester, and phenyl ester. Among these, sodium hypophosphite is preferable.
Furthermore, in order to prevent the polymerization catalyst from aggregating in the polyamide resin or causing an abnormal reaction due to deterioration during heating, an alkali metal and an alkaline earth metal compound can be added together. Specifically, sodium hydroxide, calcium hydroxide, potassium hydroxide, magnesium hydroxide and carbonic acid, boric acid, acetic acid, propionic acid, butyric acid, isobutyric acid, crotonic acid, valeric acid, caproic acid, isocaproic acid, enanthic acid , Caprylic acid, pelargonic acid, stearic acid, cyclopentanecarboxylic acid, cyclohexanecarboxylic acid, hydrocinnamic acid, γ-phenylbutyric acid, p-phenoxybenzoic acid, o-oxycinnamic acid, o-β-chlorophenylpropionic acid, m -Alkali metal and alkaline earth metal compounds of chlorophenylpropionic acid are exemplified, but not limited to these compounds. Among these, sodium acetate is preferable.

  The polyamide resin (A) used in the resin composition of the present invention preferably contains a phosphorus compound so that the phosphorus atom concentration in the finally obtained polyamide resin composition is 50 to 1,000 ppm. In the present invention, the phosphorus atom concentration in the polyamide resin composition means the concentration of phosphorus atoms remaining in the organic component after removing inorganic components such as the filler (D) described later from the polyamide resin composition. And Many phosphorus compounds are derived from the above-described polymerization catalyst, but are not particularly limited. The phosphorus atom concentration in the polyamide resin (A) is preferably 50 to 1,000 ppm, more preferably 100 to 800 ppm, still more preferably 150 to 600 ppm, and particularly preferably 200 to 400 ppm. When the phosphorus atom concentration in the polyamide resin (A) is less than 50 ppm, it tends to be yellowed during compounding or during molding of the polyamide resin composition. On the other hand, if it exceeds 1,000 ppm, the thermal stability tends to deteriorate and the mechanical strength tends to decrease. The phosphorus atom concentration can be adjusted by adjusting the type, amount and polymerization conditions of the polymerization catalyst during the polymerization of the polyamide resin (A), or by extracting the obtained polyamide resin (A) with an extraction solvent such as water or hot water. It is possible to adjust by washing the catalyst and removing an excess of the catalyst residue. In the present invention, a method of adjusting the type and amount of the polymerization catalyst is preferable.

  The phosphorus atom concentration in the polyamide resin (A) can be measured at a wavelength of 213.618 nm by high-frequency inductively coupled plasma (ICP) emission analysis after wet decomposition of the polyamide resin (A) with concentrated sulfuric acid.

Moreover, it is preferable that the density of a polyamide resin (A) is 1.1-1.2 g / cm < ³ >. Within this range, the polyamide resin composition can have both strength and lightness. More preferably, it is the range of 1.11-1.165 g / cm < ³ >.
The density of the polyamide resin (A) can be measured in accordance with JIS K7112 A method (underwater substitution method).

Further, the polyamide resin (A) used in the resin composition of the present invention preferably has a moisture content of 0.01 to 0.5% by mass, more preferably 0.02 to 0.4% by mass, More preferably, it is 0.03-0.3 mass%, Most preferably, it is 0.05-0.2 mass%.
When the moisture content is higher than 0.5% by mass, the polyamide resin (A) is easily hydrolyzed when the filler is compounded, and mechanical properties such as rigidity and impact strength of the obtained resin composition are lowered. This is not preferable. On the other hand, when the moisture content is lower than 0.01% by mass, the polyamide resin (A) may turn yellow when the polyamide resin (A) is dried, which is not preferable. Further, when compounding a stabilizer (D) described later, particularly an inorganic type, particularly a copper compound type stabilizer, the dispersion of the stabilizer (D) is poor when the moisture content is lower than 0.01% by mass. Thus, physical properties such as heat resistance of the obtained polyamide resin composition may be lowered, which is not preferable.

  In order to adjust the moisture content within such a range, a conventionally known method can be employed. For example, when a polyamide resin is melt-extruded with an extruder equipped with a vent, water is removed from the polymer by reducing the vent holes, and the polyamide resin is charged into a tumbler (rotary vacuum tank) to remove air, A method of drying by heating at a temperature lower than the melting point of the polyamide resin under an active gas atmosphere or under reduced pressure is exemplified, but the method is not limited thereto. The moisture content can also be optimized by adjusting the types and composition ratios of the raw material diamine component and dicarboxylic acid component.

The moisture content here can be measured by the Karl Fischer method using pellets of polyamide resin (A). The measurement temperature is a melting point of polyamide of −5 ° C., and the measurement time is 30 minutes.
Moreover, 0.01-0.5 mass% is preferable and, as for the water absorption rate (after 7 days of 23 degreeC water immersion) of a polyamide resin (A), 0.01-0.45 mass% is more preferable. The water absorption rate of the polyamide resin (A) is determined by the Karl Fischer method after injection molding of only the polyamide resin (A) and immersing the resulting molded piece in water at 23 ° C. for 7 days. Can be sought. The measurement temperature is -5 ° C. and the measurement time is 30 minutes.
It is preferable for the polyamide resin (A) to have a water absorption rate in the above-mentioned range since the water absorption of the polyamide resin composition can be suppressed and the strength reduction due to the water absorption of the molded product made of the polyamide resin composition can be suppressed.

The number average molecular weight (Mn) of the polyamide resin (A) is preferably 18,000 to 70,000, more preferably 20, as a PMMA (polymethyl methacrylate) conversion value by GPC (gel permeation chromatography) measurement. 000 to 50,000. Within this range, heat resistance, elastic modulus, dimensional stability, and moldability are good. The melting point of the polyamide resin (A) is preferably 150 to 300 ° C. Moreover, 55-100 degreeC is preferable and, as for the glass transition point (Tg) of a polyamide resin (A), More preferably, it is 60-100 degreeC. Within this range, the heat resistance is good and the moldability is good.
The melting point and glass transition point of the polyamide resin (A) can be measured by a differential scanning calorimetry (DSC) method. After the sample is heated and melted once, the influence of the thermal history on the crystallinity is eliminated, and then again. It refers to the melting point and glass transition point measured at elevated temperatures. Specifically, for example, the temperature is raised at a rate of 10 ° C./min from 30 ° C. to a temperature higher than the expected melting point, held for 2 minutes, and then lowered to 30 ° C. at a rate of 20 ° C./min. Next, the temperature is raised to a temperature higher than the melting point at a rate of 10 ° C./min, and the melting point and glass transition point can be determined.

Further, the polyamide resin (A) of the present invention includes a resin other than the polyamide resin (A), for example, a polyphenylene ether resin, a polystyrene resin, a polyester resin, a polyolefin resin, a polyphenylene, within a range that does not impair the object and effect of the present invention. One or a plurality of thermoplastic resins such as sulfide resin and polycarbonate resin can be blended.
Further, in the present invention, the effects of the present invention can be sufficiently achieved without blending a polyamide resin other than the polyamide resin (A). Polyamide 6, polyamide 66, polyamide 11, polyamide 12, polyamide 46 Adding aliphatic polyamide resins such as polyamide 6/10, polyamide 6/12, polyamide 6/66, and aromatic polyamide resins such as polyamide 6I, polyamide 6T, polyamide 6I / 6T, and polyamide 9T alone or in combination Do not exclude. When a polyamide resin other than the polyamide resin (A) is blended, among these, the blending of polyamide 6 and / or polyamide 66 increases the crystallization speed of the polyamide resin composition and further increases the molding cycle during molding. This is preferable because it can be shortened.

[3. Filler (B)]
The filler (B) to be blended in the polyamide resin composition of the present invention is not particularly limited as long as it is generally used in this type of composition, and powder, fibrous, granular and plate-like inorganic fillers are used. Resin-based fillers or natural fillers can also be preferably used.
The powdery and granular fillers preferably have a particle size of 100 μm or less, more preferably 80 μm or less, carbonates such as kaolinite, silica, calcium carbonate, magnesium carbonate, calcium sulfate, magnesium sulfate. And sulfates such as alumina, glass beads, carbon black, sulfides and metal oxides can be used. As the fibrous filler, glass fibers, potassium titanate or calcium sulfate whiskers, wollastonite, carbon fibers, mineral fibers, alumina fibers, and the like can be used. Examples of the plate-like filler include glass flake, mica, talc, clay, graphite, sericite and the like. Among these, at least one selected from glass fiber, talc, mica, and wollastonite is preferable, and glass fiber is particularly preferable.
Examples of the resin filler include aromatic liquid crystalline polyester resin, wholly aromatic polyamide resin, acrylic fiber, poly (benzimidazole) fiber, and the like.
Examples of natural fillers include kenaf, pulp, hemp pulp, and wood pulp.

  Content of a filler (B) is 15-200 mass parts with respect to 100 mass parts of polyamide resins (A), Preferably it is 30-180 mass parts, More preferably, it is 50-150 mass parts. When the content is less than 15 parts by mass, the mechanical strength of the obtained polyamide resin composition molded article is insufficient. On the other hand, when it exceeds 200 mass parts, the fluidity | liquidity of a polyamide resin composition will deteriorate, and melt-kneading, shaping | molding, etc. will become difficult.

  In the polyamide resin composition of the present invention, a crystal nucleating agent can be used according to the required molding processability. Examples of the crystal nucleating agent include talc and boron nitride which are generally used, but an organic nucleating agent may also be used. In the case of an organic nucleating agent or boron nitride, the content of the nucleating agent is 0.001 to 6 parts by mass, preferably 0.02 to 2 parts by mass, and more preferably 0.02 parts by mass with respect to 100 parts by mass of the polyamide resin (A). It is 05-1 mass part. If the amount is too small, the expected nucleating agent effect may not be obtained, and the releasability may decrease. If the amount is too large, impact resistance and surface appearance tend to decrease. When using talc, it is 0.1-8 mass parts, Preferably it is 0.3-2 mass parts. In the case of an inorganic nucleating agent other than talc and boron nitride, the amount is 0.3 to 8 parts by mass, preferably 0.5 to 4 parts by mass. If the amount is too small, the nucleating agent effect cannot be obtained, and if the amount is too large, a foreign matter effect is caused and mechanical strength and impact resistance value tend to decrease. In the present invention, talc or boron nitride is preferably blended from the viewpoint of mechanical properties such as impact resistance, tensile elongation and bending deflection.

  As the talc, those having a number average particle diameter of 2 μm or less are preferable. As boron nitride, the number average particle diameter is usually 10 μm or less, preferably 0.005 to 5 μm, more preferably 0.01 to 3 μm. The number average particle diameter of talc is usually a value obtained by measurement using a laser diffraction / scattering particle size distribution meter.

[4. Additive]
[4.1 Hydrolysis resistance improver-carbodiimide compound (C)]
It is preferable to mix | blend the carbodiimide compound (C) as a hydrolysis-resistance improving agent with the polyamide resin composition of this invention. Preferred examples of the carbodiimide compound include aromatic, aliphatic or alicyclic polycarbodiimide compounds produced by various methods. Among these, an aliphatic or alicyclic polycarbodiimide compound is preferable, and an alicyclic polycarbodiimide compound is more preferably used from the viewpoint of melt kneadability at the time of extrusion or the like.

  These carbodiimide compounds (C) can be produced by decarboxylation condensation reaction of organic polyisocyanate. For example, a method of synthesizing various organic polyisocyanates by decarboxylation condensation reaction at a temperature of about 70 ° C. or higher in an inert solvent or without using a solvent in the presence of a carbodiimidization catalyst can be exemplified. . The isocyanate group content is preferably 0.1 to 5%, more preferably 1 to 3%. By setting it as the above ranges, the reaction with the polyamide resin (A) becomes easy and the hydrolysis resistance tends to be good.

As organic polyisocyanate which is a synthesis raw material of the carbodiimide compound (C), for example, various organic diisocyanates such as aromatic diisocyanate, aliphatic diisocyanate, and alicyclic diisocyanate, and mixtures thereof can be used.
Specific examples of the organic diisocyanate include 1,5-naphthalene diisocyanate, 4,4′-diphenylmethane diisocyanate, 4,4′-diphenyldimethylmethane diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 2 , 4-tolylene diisocyanate, 2,6-tolylene diisocyanate, hexamethylene diisocyanate, cyclohexane-1,4-diisocyanate, xylylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4-diisocyanate, methylcyclohexane diisocyanate, tetramethylxylylene Range isocyanate, 2,6-diisopropylphenyl isocyanate, 1,3,5-triisopropylbenzene-2,4-di Isocyanate, methylenebis (4,1-cyclohexylene) = can be exemplified diisocyanate may be used in combination of two or more thereof. Among these, dicyclohexylmethane-4,4-diisocyanate and methylenebis (4,1-cyclohexylene) = diisocyanate are preferable.

  In order to seal the terminal of the carbodiimide compound (C) and control the degree of polymerization, it is also preferable to use a terminal blocking agent such as monoisocyanate. Examples of the monoisocyanate include phenyl isocyanate, tolyl isocyanate, dimethylphenyl isocyanate, cyclohexyl isocyanate, butyl isocyanate, and naphthyl isocyanate, and two or more kinds may be used in combination.

  In addition, as terminal blocker, it is not limited to said monoisocyanate, What is necessary is just an active hydrogen compound which can react with isocyanate. Examples of such active hydrogen compounds include aliphatic, aromatic, and alicyclic compounds such as methanol, ethanol, phenol, cyclohexanol, N-methylethanolamine, polyethylene glycol monomethyl ether, and polypropylene glycol monomethyl ether. -OH group compounds, secondary amines such as diethylamine and dicyclohexylamine, primary amines such as butylamine and cyclohexylamine, carboxylic acids such as succinic acid, benzoic acid and cyclohexanecarboxylic acid, ethyl mercaptan, allyl mercaptan, thiophenol, etc. Examples of these compounds include thiols and compounds having an epoxy group, and two or more of them may be used in combination.

  Examples of the carbodiimidization catalyst include 1-phenyl-2-phospholene-1-oxide, 3-methyl-1-phenyl-2-phospholene-1-oxide, 1-ethyl-2-phospholene-1-oxide, 3- Metal catalysts such as methyl-2-phospholene-1-oxide and phospholene oxides such as these 3-phospholene isomers, tetrabutyl titanate, etc. can be used. -Methyl-1-phenyl-2-phospholene-1-oxide is preferred. Two or more carbodiimidization catalysts may be used in combination.

  The content of the carbodiimide compound (C) is preferably 0.1 to 2 parts by mass, more preferably 0.1 to 1.5 parts by mass, further preferably 100 parts by mass of the polyamide resin (A). The amount is 0.2 to 1.5 parts by mass, particularly preferably 0.3 to 1.5 parts by mass. If the amount is less than 0.1 parts by mass, the resin composition does not have sufficient hydrolysis resistance, uneven discharge during melt kneading such as extrusion tends to occur, and melt kneading tends to be insufficient. On the other hand, when it exceeds 2 parts by mass, the viscosity of the resin composition during melt kneading is remarkably increased, and melt kneadability and moldability are liable to deteriorate.

[4.2 Stabilizer (D)]
The polyamide resin (A) of the present invention preferably contains a stabilizer (antioxidant, heat stabilizer). Examples of the stabilizer include aromatic secondary amine-based, organic sulfur-based, phosphorus-based and phenol-based organic stabilizers, and inorganic stabilizers such as copper compounds and halides.

Aromatic secondary amine stabilizer:
As the aromatic secondary amine stabilizer, a compound having a diphenylamine skeleton, a compound having a phenylnaphthylamine skeleton, and a compound having a dinaphthylamine skeleton are preferable, and a compound having a diphenylamine skeleton and a compound having a phenylnaphthylamine skeleton are more preferable.

Specifically, p, p′-dialkyldiphenylamine (carbon number of alkyl group: 8 to 14), octylated diphenylamine, 4,4′-bis (α, α-dimethylbenzyl) diphenylamine, p- (p-toluene) Sulfonylamido) diphenylamine, N, N'-diphenyl-p-phenylenediamine, N-phenyl-N'-isopropyl-p-phenylenediamine, N-phenyl-N '-(1,3-dimethylbutyl) -p-phenylene A compound having a diphenylamine skeleton such as diamine and N-phenyl-N ′-(3-methacryloyloxy-2-hydroxypropyl) -p-phenylenediamine;
Compounds having a phenylnaphthylamine skeleton such as N-phenyl-1-naphthylamine and N, N′-di-2-naphthyl-p-phenylenediamine;
Compounds having a dinaphthylamine skeleton such as 2,2'-dinaphthylamine, 1,2'-dinaphthylamine, and 1,1'-dinaphthylamine;
Alternatively, a mixture thereof can be exemplified, but not limited thereto.

  Among these, 4,4′-bis (α, α-dimethylbenzyl) diphenylamine, N, N′-di-2-naphthyl-p-phenylenediamine and N, N′-diphenyl-p-phenylenediamine are preferable, N, N′-di-2-naphthyl-p-phenylenediamine and 4,4′-bis (α, α-dimethylbenzyl) diphenylamine are particularly preferred.

・ Organic sulfur stabilizers:
As the organic sulfur stabilizer, a mercaptobenzimidazole compound, a dithiocarbamic acid compound, a thiourea compound, and an organic thioacid compound are preferable, and a mercaptobenzimidazole compound and an organic thioacid compound are more preferable.
Specifically, mercaptobenzimidazole compounds such as 2-mercaptobenzimidazole, 2-mercaptomethylbenzimidazole, and metal salts of 2-mercaptobenzimidazole;
Dilauryl-3,3'-thiodipropionate, dimyristyl-3,3'-thiodipropionate, distearyl-3,3'-thiodipropionate, and pentaerythritol tetrakis (3-laurylthiopropionate) Organic thioic acid compounds such as
Dithiocarbamic acid compounds such as metal salts of diethyldithiocarbamic acid and metal salts of dibutyldithiocarbamic acid;
And thiourea compounds such as 1,3-bis (dimethylaminopropyl) -2-thiourea and tributylthiourea;
Alternatively, a mixture thereof can be exemplified, but is not limited thereto.

Among these, 2-mercaptobenzimidazole, 2-mercaptomethylbenzimidazole, dimyristyl-3,3'-thiodipropionate, distearyl-3,3'-thiodipropionate and pentaerythritol tetrakis (3-laurylthio) Propionate) is preferred, pentaerythritol tetrakis (3-laurylthiopropionate), 2-mercaptobenzimidazole, and dimyristyl-3,3'-thiodipropionate are more preferred, and pentaerythritol tetrakis (3-laurylthio). Propionate) is particularly preferred.
The molecular weight of the organic sulfur compound is usually 200 or more, preferably 500 or more, and the upper limit is usually 3,000.

  When blending the above organic sulfur stabilizer or aromatic secondary amine stabilizer, it is preferable to use them together. By using these in combination, the heat aging resistance of the polyamide resin composition tends to be better than when used alone.

  As a more preferable combination of the organic sulfur stabilizer and the aromatic secondary amine stabilizer, dimyristyl-3,3′-thiodipropionate, 2-mercaptomethylbenzoate may be used as the organic sulfur stabilizer. At least one selected from imidazole and pentaerythritol tetrakis (3-laurylthiopropionate) and an aromatic secondary amine stabilizer are 4,4′-bis (α, α-dimethylbenzyl) diphenylamine and N , N′-di-2-naphthyl-p-phenylenediamine, and a combination thereof. Further, the organic sulfur stabilizer is pentaerythritol tetrakis (3-lauryl thiopropionate), and the aromatic secondary amine stabilizer is N, N'-di-2-naphthyl-p-phenylenediamine. Is more preferable.

  When the organic sulfur stabilizer and the aromatic secondary amine stabilizer are used in combination, the content ratio (mass ratio) in the polyamide resin composition is such that the aromatic secondary amine stabilizer / The organic sulfur stabilizer is preferably 0.05 to 15, more preferably 0.1 to 5, and further preferably 0.2 to 2. By setting it as such content ratio, heat aging resistance can be improved efficiently, maintaining barrier property.

・ Phenolic stabilizers:
Examples of the phenol-based stabilizer include 2,2′-methylenebis (4-methyl-6-tert-butylphenol), 4,4′-butylidenebis (6-tert-butyl-3-methylphenol), 4,4 ′. -Thiobis (6-tert-butyl-3-methylphenol), 3,9-bis [2- [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] -1,1- Dimethylethyl] -1,4,8,10-tetraoxaspiro [5.5] undecane, triethylene glycol-bis [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate], 1 , 6-hexanediol-bis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 2,4-bis- (n-octylthio) -6- (4- Droxy-3,5-di-t-butylanilino) -1,3,5-triazine, pentaerythritol tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 2,2- Thio-diethylenebis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, N, N′-hexamethylene bis (3,5-di-tert-butyl-4-hydroxy-hydrocinnamamide), 3,5-di-tert-butyl-4-hydroxybenzylphosphonate-diethyl ester,
1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, tris- (3,5-di-tert-butyl-4-hydroxybenzyl) ) -Isocyanurate, 2,4-bis [(octylthio) methyl] -o-cresol, isooctyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, and the like. It is not limited.

  Among these, octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, 1,6-hexanediol-bis [3- (3,5-di-t-butyl-4- Hydroxyphenyl) propionate], pentaerythritol tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], N, N′-hexamethylenebis (3,5-di-t-butyl- 4-hydroxy-hydrocinnamamide), 3,9-bis [2- [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] -1,1-dimethylethyl] -2 , 4,8,10-tetraoxaspiro [5.5] undecane and N, N'-hexamethylenebis (3,5-di-tert-butyl-4-hydroxy-hydrocin Hindered phenolic stabilizer Mamido) are preferably exemplified.

・ Phosphorus stabilizer:
As a phosphorus stabilizer, a phosphite type and a phosphonite type are preferable.
Examples of the phosphite compound include distearyl pentaerythritol diphosphite, dinonylphenyl pentaerythritol diphosphite, bis (2,4-di-t-butylphenyl) pentaerythritol diphosphite, and bis (2,6- Di-t-butyl-4-methylphenyl) pentaerythritol diphosphite, bis (2,6-di-t-butyl-4-ethylphenyl) pentaerythritol diphosphite, bis (2,6-di-t- Butyl-4-isopropylphenyl) pentaerythritol diphosphite, bis (2,4,6-tri-t-butylphenyl) pentaerythritol diphosphite, bis (2,6-di-t-butyl-4-sec-) Butylphenyl) pentaerythritol diphosphite, bis (2,6-di-) -Butyl-4-t-octylphenyl) pentaerythritol diphosphite, bis (2,4-dicumylphenyl) pentaerythritol diphosphite and the like, and in particular, bis (2,6-di-t-butyl- 4-methylphenyl) pentaerythritol diphosphite and bis (2,4-dicumylphenyl) pentaerythritol diphosphite are preferred.

  Examples of the phosphonite compound include tetrakis (2,4-di-t-butylphenyl) -4,4′-biphenylenediphosphonite, tetrakis (2,5-di-t-butylphenyl) -4,4′-. Biphenylene diphosphonite, tetrakis (2,3,4-trimethylphenyl) -4,4'-biphenylene diphosphonite, tetrakis (2,3-dimethyl-5-ethylphenyl) -4,4'-biphenylene diphosphonite Tetrakis (2,6-di-t-butyl-5-ethylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,3,4-tributylphenyl) -4,4'-biphenylenediphosphonite , Tetrakis (2,4,6-tri-t-butylphenyl) -4,4'-biphenylenediphosphonite and the like, Tetrakis (2,4-di -t- butyl-phenyl) -4,4'-biphenylene phosphonite are preferred.

・ Inorganic stabilizers:
As the inorganic stabilizer, a copper compound and a halide are preferable.
The copper compound used as the inorganic stabilizer is a copper salt of various inorganic acids or organic acids, and excludes halides described later. The copper may be either cuprous or cupric. Specific examples thereof include copper chloride, copper bromide, copper iodide, copper phosphate, copper stearate, hydrotalcite, styreneite, pyrone. Examples include natural minerals such as light.

  Examples of the halide used as the inorganic stabilizer include, for example, alkali metal or alkaline earth metal halides; ammonium halides and quaternary ammonium halides of organic compounds; alkyl halides, allyl halides. Specific examples thereof include ammonium iodide, stearyltriethylammonium bromide, benzyltriethylammonium iodide, and the like. Among these, alkali metal halide salts such as potassium chloride, sodium chloride, potassium bromide, potassium iodide, sodium iodide and the like are preferable.

  The combined use of a copper compound and a halide, in particular, the combined use of a copper compound and a halogenated alkali metal salt is preferable because it exhibits excellent effects in terms of heat discoloration resistance and weather resistance (light resistance). For example, when a copper compound is used alone, the molded product may be colored reddish brown by copper, and this coloring is not preferable depending on the application. In this case, discoloration to reddish brown can be prevented by using a copper compound and a halide together.

  In the present invention, among the stabilizers described above, in particular, inorganic, aromatic secondary amine or organic sulfur from the viewpoints of processing stability at the time of melt molding, heat aging resistance, appearance of molded products, and prevention of coloring. System stabilizers are particularly preferred.

  It is preferable that content of the said stabilizer (D) is 0.01-1 mass part with respect to 100 mass parts of polyamide resins (A), More preferably, it is 0.01-0.8 mass part. . By setting the content to 0.01 parts by mass or more, the effect of improving thermal discoloration and improving weather resistance / light resistance can be sufficiently exhibited. By setting the content to 1 part by mass or less, the appearance of the molded product Defects and deterioration of mechanical properties can be suppressed.

[4.3 Other additives]
The polyamide resin composition of the present invention includes a matting agent, an ultraviolet absorber, a plasticizer, a dispersant, a flame retardant, an antistatic agent, an anti-coloring agent, an anti-gelling agent, as long as the effects of the present invention are not impaired. Additives such as colorants, mold release agents, impact resistance improvers, and the like can be added.

[5 Polyamide resin composition production method]
The method for producing the polyamide resin composition of the present invention is not particularly limited, and the polyamide resin composition (A), the filler (B), and other components to be blended as necessary may be arbitrarily selected. It can manufacture by mixing and kneading in this order. Of these, a melt kneading method using various commonly used extruders such as a single screw or twin screw extruder is preferable, and a method using a twin screw extruder is particularly preferable from the viewpoint of productivity and versatility. At that time, the melt kneading temperature is preferably adjusted to 200 to 300 ° C., and the residence time is preferably adjusted to 10 minutes or less, and the screw has at least one reverse screw element and / or kneading disk, It is preferable to melt and knead while partly staying. By setting the melt-kneading temperature within the above range, it tends to be difficult for extrusion-kneading failure and resin decomposition to occur. Moreover, when mix | blending glass fiber as a filler, it is preferable to carry out the side feed from the middle of an extruder, and to melt-knead.

  The moisture content of the polyamide resin composition thus obtained is preferably 0.01 to 0.1% by mass. More preferably, it is 0.02-0.09 mass%, More preferably, it is 0.03-0.08 mass%. When the moisture content is lower than 0.01% by mass, the polyamide resin composition is easily charged, and during molding, the composition pellets are likely to adhere to a molding machine hopper, feeder, etc., which may hinder molding. On the other hand, if it is higher than 0.1% by mass, it is not preferred because it may be hydrolyzed during molding and physical properties such as the modulus of elasticity of the resulting molded product may be reduced, or long-term physical property stability may be reduced.

  The moisture content of the polyamide resin composition can be adjusted by, for example, the drying method, the degree of decompression of the extruder vacuum vent during compounding, the degree of subsequent cooling, and the like. When the polyamide resin composition is dried, it can be performed by a known method. For example, a polyamide resin composition is charged into a heatable tumbler (rotary vacuum tank) equipped with a vacuum pump or a vacuum dryer, and the target moisture content is maintained at a temperature below the melting point of the polymer, preferably below 160 ° C. under reduced pressure. Examples of the method include drying by heating for an appropriate time so as to achieve a rate, but are not limited thereto. The moisture content can also be optimized by adjusting the types and composition ratios of the raw material diamine component and dicarboxylic acid component.

  The moisture content here can be measured by a Karl Fischer method using a pellet of a polyamide resin composition. The measurement temperature is the melting point of the polyamide resin (A) −5 ° C., and the measurement time is 30 minutes.

  Moreover, it is preferable that the phosphorus atom density | concentration in the polyamide resin composition of this invention is 50-1,000 ppm. Many phosphorus atoms are derived from the polymerization catalyst of the polyamide resin (A) described above, but are not particularly limited. The phosphorus atom concentration in the polyamide resin composition is more preferably 100 to 800 ppm, further preferably 150 to 600 ppm, and particularly preferably 200 to 400 ppm. If the concentration of phosphorus atoms in the polyamide resin composition is less than 50 ppm, yellowing tends to occur during compounding or during molding of the polyamide resin composition. On the other hand, if it exceeds 1,000 ppm, the thermal stability tends to deteriorate and the mechanical strength tends to decrease. In the present invention, the phosphorus atom concentration in the polyamide resin composition is the phosphorus atom concentration remaining in the organic component after removing the inorganic component such as the filler (D) from the polyamide resin composition. .

  The phosphorus atom concentration in the polyamide resin composition can be adjusted by adjusting the type, amount and polymerization conditions of the polymerization catalyst during the polymerization of the polyamide resin (A), which is the raw material of the resin composition, It can adjust by washing | cleaning by extracting with extraction solvents, such as water, and removing the excess of a catalyst. In addition, when the polyamide resin composition of the present invention is produced, the polyamide resin (A) and the filler (B) can be adjusted by further blending various additives having phosphorus atoms such as a phosphorus stabilizer. it can. In the present invention, a method of adjusting the kind and amount of the polymerization catalyst of the polyamide resin (A) is preferable.

  The phosphorus atom concentration in the polyamide resin (A) can be measured at a wavelength of 213.618 nm by high-frequency inductively coupled plasma (ICP) emission analysis after wet decomposition of the polyamide resin composition with concentrated sulfuric acid.

  As described above, a particularly preferred embodiment of the present invention has a moisture content of the raw material polyamide resin (A) of 0.01 to 0.5% by mass and a polyamide resin composition to be obtained has a moisture content of 0.01. It is a case of -0.1 mass%. Even if the moisture content of the target polyamide resin composition is adjusted to 0.01 to 0.1% by mass using the raw material polyamide resin (A) having a moisture content exceeding 0.5% by mass, the present invention The desired effect may not be obtained. On the contrary, even when the raw material polyamide resin (A) has a moisture content of 0.01 to 0.5% by mass, the resulting polyamide resin composition has a moisture content outside the above range. The desired effect may not be obtained. By making both the moisture content of the raw material polyamide resin (A) and the polyamide resin composition obtained using the same within the above range, it is light, has a low water absorption rate, has a high crystallization speed, and is mechanically It becomes easy to obtain a polyamide resin composition having excellent strength, appearance, and color tone.

The polyamide resin composition of the present invention can be molded into molded products of various forms by a conventionally known molding method. Examples of the molding method include injection molding, blow molding, extrusion molding, compression molding, vacuum molding, press molding, direct blow molding, rotational molding, sandwich molding, and two-color molding.
Further, when the polyamide resin composition of the present invention is molded especially for injection molding, the crystallization speed is fast, so that the appearance and accuracy of the molded product are extremely good, and an injection molded product with excellent quality can be obtained. it can.

  Hereinafter, although an example and a comparative example explain the present invention still in detail, the present invention is not limited to these examples.

[Evaluation methods]
Moisture content, water absorption rate, density of the polyamide resin (A) used in Examples and Comparative Examples, and moisture content, phosphorus atom concentration, crystallization state, releasability of the polyamide resin composition obtained by the method described below, Charpy impact strength, YI (yellow index) value, and molded product appearance were measured as follows.

(1) Moisture content Using the polyamide resin (A) or pellets of the polyamide resin composition obtained by the method described below, the measurement was carried out by the Karl Fischer method at a melting point of the polyamide resin of -5 ° C for a measurement time of 30 minutes.
(2) Water absorption rate Using the polyamide resin (A), an ISO test piece was prepared on an injection molding machine 100T manufactured by FANUC under conditions of a cylinder temperature of 280 ° C and a mold temperature of 100 ° C. The obtained test piece was immersed in distilled water for 1 week under the condition of 23 ° C., then the surface adhering water was removed, and the water content was measured by the Karl Fischer method to obtain the water absorption rate. Hiranuma Sangyo Co., Ltd. trace moisture measuring device AQ-2000 was used for the measurement. The measurement temperature was the melting point of the polyamide resin −5 ° C., and the measurement time was 30 minutes.

(3) Density The density of the polyamide resin (A) was measured according to JIS K7112 A method (underwater substitution method).

(4) Phosphorus atom concentration 0.5 g of polyamide resin (A) or a polyamide resin composition obtained by the method described below was weighed, 20 ml of concentrated sulfuric acid was added, and wet decomposition was performed on a heater. After cooling, 5 ml of hydrogen peroxide was added, heated on a heater, and concentrated until the total amount became 2-3 ml. The mixture was cooled again to 500 ml with pure water. Quantification was performed at a wavelength of 213.618 nm by high frequency inductively coupled plasma (ICP) emission analysis using IRIS / IP manufactured by Thermo Jarrel Ash. In the present invention, the phosphorus atom concentration in the polyamide resin composition means the concentration of phosphorus atoms remaining in the organic component after removing inorganic components such as the filler (D) described later from the polyamide resin composition. And

(5) Crystallization situation Using a polyamide resin composition obtained by the method described below, at an injection molding machine SE50 manufactured by Sumitomo Heavy Industries, Ltd., a cylinder temperature of 280 ° C., a mold temperature of 100 ° C., and a cooling time of 12 seconds. Under the conditions, a test piece of 10 mm × 100 mm × thickness 1 mm was produced. The obtained test piece was subjected to DSC measurement, and the amount of crystallization was measured according to JIS K-7122. The apparatus was DSC-60 manufactured by Shimadzu Corporation, and the temperature was raised to a temperature 30 ° C. higher than the expected melting point at a rate of temperature rise of 10 ° C./min in a nitrogen atmosphere.
From the crystallization peak observed at the time of temperature rise, the crystallization state was evaluated according to the following criteria. If the evaluation result is Δ, ○, it is at a level where there is no problem even if it is used as an actual molded product.
◯: No temperature rising crystallization peak Δ: Crystallization heat of crystallization peak is less than 8 mJ / mg ×: Crystallization heat of crystallization peak is 8 mJ / mg or more

(6) Appearance of molded product 10 mm × under conditions of cylinder temperature 280 ° C. and mold temperature 100 ° C. using injection molding machine SE50 manufactured by Sumitomo Heavy Industries, Ltd. using the polyamide resin composition obtained by the method described below. A test piece of 100 mm × 1 mm thickness was produced. The obtained test piece was visually observed and judged according to the following criteria.
○: No glass fiber (GF) floating △: Some GF floating ×: GF floating

(7) Releasability Using a polyamide resin composition obtained by the method described below, a cylinder temperature of 280 ° C., a mold temperature of 100 ° C., and a cooling time of 12 seconds was used in an injection molding machine SE50 manufactured by Sumitomo Heavy Industries, Ltd. Under the conditions, the deformation state of the test piece at the time of mold release when a 10 × 100 × 1 mm-thick test piece was injection-molded was visually confirmed and determined as follows.
○: No deformation ×: Deformation

(8) Charpy impact strength Using a polyamide resin composition obtained by the method described below, an ISO test piece was produced on a FANUC injection molding machine 100T under conditions of a cylinder temperature of 280 ° C and a mold temperature of 120 ° C. Then, evaluation was carried out according to ISO 179 (unit: KJ / m ² ).

(9) YI value Using a polyamide resin composition obtained by the method described below, a 3 mm-thick flat plate was produced using a FANUC injection molding machine 100T under conditions of a cylinder temperature of 280 ° C and a mold temperature of 120 ° C. The obtained test piece was measured by a reflection method using a SE2000 type spectrocolorimeter manufactured by Nippon Denshoku Industries Co., Ltd. according to JIS K-7105.

[material]
The following were used as glass fibers and crystal nucleating agents for blending with the polyamide resin (A).
・ Glass fiber (B):
Nippon Electric Glass Co., Ltd., chopped strand, trade name "T-275H"
-Crystal nucleating agent-fine talc:
Product name “Micron White # 5000S” manufactured by Hayashi Kasei Co., Ltd.

Moreover, the following were used as an additive for mix | blending with a polyamide resin.
-Carbodiimide compound (C):
Alicyclic polycarbodiimide compound, Nisshinbo Co., Ltd., trade name “Carbodilite LA-1”
Hereinafter, this carbodiimide compound is abbreviated as “carbodiimide”.
Aromatic secondary amine stabilizer:
N, N'-di-2-naphthyl-p-phenylenediamine, manufactured by Ouchi Shinsei Chemical Industry Co., Ltd., trade name "NOCRACK white"
Hereinafter, it is abbreviated as “stabilizer”.
・ Copper chloride / potassium iodide mixture:
Mixture of copper chloride: potassium iodide = 1: 10 (mass ratio) Hereinafter, abbreviated as “CuCl / KI”.

Example 1
As the polyamide resin (A), the polyamide resin obtained in Production Example 1 below was used.
<Production Example 1>
In a reaction vessel equipped with a stirrer, a partial condenser, a full condenser, a thermometer, a dropping funnel and a nitrogen introducing tube, and a strand die, 12,135 g (60 mol) of sebacic acid precisely weighed, sodium hypophosphite monohydrate Product (NaH ₂ PO ₂ .H ₂ O) 3.105 g (phosphorus atom concentration in the polyamide resin 50 ppm) and 1.61 g of sodium acetate were sufficiently substituted with nitrogen, and then the system was added under a small amount of nitrogen stream. Was heated to 170 ° C. with stirring. The molar ratio of sodium hypophosphite monohydrate / sodium acetate was 0.67.
To this, 7,172 g (60 mol) of a mixed diamine of 7: 3 of metaxylylenediamine and paraxylylenediamine was dropped while stirring, and the inside of the system was continuously heated while removing the condensed water to be generated outside the system. . After completion of the dropwise addition of the mixed xylylenediamine, the melt polymerization reaction was continued for 40 minutes at an internal temperature of 260 ° C.
Thereafter, the inside of the system was pressurized with nitrogen, the polymer was taken out from the strand die, and pelletized to obtain about 24 kg of polyamide resin. The obtained pellets were dried with dehumidified air at 80 ° C. (dew point −40 ° C.) for 1 hour.
The moisture content and density of this polyamide resin were as shown in Table 1.

  The polyamide resin obtained in Production Example 1 was weighed so that the composition shown in Table 1 was obtained, and the components other than the glass fiber were blended with a tumbler. The glass fiber was side-fed after being introduced and melted from the base of “TEM26SS”). The set temperature of the extruder was 280 ° C. up to the side feed part, and 260 ° C. from the side feed part, and extruded and pelletized to prepare polyamide resin composition pellets. The obtained polyamide resin composition pellets were dried with dehumidified air at 80 ° C. (dew point −40 ° C.) for 8 hours. The moisture content of the polyamide resin composition pellets was as shown in Table 1.

(Examples 2 to 5)
In Production Example 1, the mixing ratio of metaxylylenediamine and paraxylylenediamine was the ratio described in Table 1, the molar ratio of sodium hypophosphite monohydrate / sodium acetate was 0.67, and hypophosphorous acid A polyamide resin was obtained in the same manner as in Production Example 1 except that the amount of sodium acid monohydrate added was increased to the phosphorus atom concentration shown in Table 1.
The same procedure as in Example 1 was performed except that the obtained polyamide resin was used and the blending amount of each component was changed to the amount shown in Table 1.
The results are shown in Table 1.

(Examples 6 to 7)
In Production Example 1, the mixing ratio of metaxylylenediamine and paraxylylenediamine was the ratio described in Table 1, sebacic acid and adipic acid having the ratio described in Table 1 were used as the dicarboxylic acid component, and hypophosphorous acid Manufacture except that the molar ratio of sodium monohydrate / sodium acetate was 0.67, and the addition amount of sodium hypophosphite monohydrate was changed to the phosphorus atom concentration shown in Table 1. A polyamide resin was obtained in the same manner as in Example 1.
The same procedure as in Example 1 was performed except that the obtained polyamide resin was used and the blending amount of each component was changed to the amount shown in Table 1.
The evaluation results are shown in Table 1.

(Examples 8 to 24)
In Example 3, the molar ratio of sodium hypophosphite monohydrate / sodium acetate was 0.67, and the addition amount of sodium hypophosphite monohydrate was changed to change the phosphorus described in Tables 2 and 3 Except for the concentration, the same procedure as in Production Example 1 was performed, and the drying time of the polyamide resin was changed as appropriate so that the moisture content of the polyamide resin became the moisture content described in Tables 2 and 3 below. A polyamide resin was obtained in the same manner as in Production Example 1 except that.
Using the obtained polyamide resin, the blending amount of each component was set to the amounts described in Tables 2 and 3, and the drying time of the obtained polyamide resin composition pellets was changed as appropriate to obtain the moisture content of the polyamide resin composition pellets. Was carried out in the same manner as in Example 3 except that the moisture contents shown in Tables 2 and 3 were set.
The results are shown in Tables 2 and 3 below.

(Comparative Examples 1-7)
The ratio of metaxylylenediamine, paraxylylenediamine, or sebacic acid and adipic acid was set to the amounts shown in Table 4 below, and in the same manner as in the above examples, sodium hypophosphite monohydrate / sodium acetate amount, dried A polyamide resin was obtained in the same manner as in Production Example 1 by appropriately changing the conditions. Using the obtained polyamide resin, the blending amount of each component was set to the amount shown in Table 4 below, and a polyamide resin composition was produced in the same manner as in the above Examples, and various evaluations were performed.
The results are shown in Table 4 below.

  The polyamide resin composition of the present invention is lighter than conventional metaxylylene adipamide resins, has a low water absorption rate, and has a high crystallization speed, so it can be used for various molded products, such as automobile parts such as automobiles, It can be used for molding molded products in a wide range of fields such as machine parts, precision machine parts, electronic / electrical equipment parts, leisure sporting goods, civil engineering and building materials, and has a very high industrial utility value.

Claims (11)

  Polyamide resin (A) in which 30 to 95 mol% of the diamine structural unit is derived from metaxylylenediamine, 70 to 5 mol% is derived from paraxylylenediamine, and 50 mol% or more of the dicarboxylic acid structural unit is derived from sebacic acid. A polyamide resin composition comprising 15 to 200 parts by mass of the filler (B) with respect to 100 parts by mass.   2. The polyamide resin composition according to claim 1, wherein the moisture content of the polyamide resin (A) is 0.01 to 0.5 mass%.   3. The polyamide resin composition according to claim 1, wherein a moisture content of the polyamide resin composition is 0.01 to 0.1% by mass. The density of a polyamide resin (A) is 1.1-1.2 g / cm < ³ >, The polyamide resin composition of any one of Claims 1-3 characterized by the above-mentioned.   The polyamide resin composition according to claim 1, wherein the polyamide resin (A) has a phosphorus atom concentration of 50 to 1,000 ppm.   The polyamide resin composition according to claim 1, wherein the polyamide resin composition has a phosphorus atom concentration of 50 to 1,000 ppm.   Furthermore, 0.1-2 mass parts of carbodiimide compounds (C) are contained with respect to 100 mass parts of polyamide resin (A), The polyamide resin composition of any one of Claims 1-6 characterized by the above-mentioned. object.   The polyamide resin composition according to claim 7, wherein the carbodiimide compound (C) is an aliphatic or alicyclic polycarbodiimide compound.   Furthermore, 0.01-1 mass part of stabilizer (D) is contained with respect to 100 mass parts of polyamide resin (A), The polyamide resin composition of any one of Claims 1-8 characterized by the above-mentioned. object.   The polyamide resin composition according to claim 9, wherein the stabilizer (D) is selected from an inorganic, aromatic secondary amine, or organic sulfur stabilizer.   The molded article formed by shape | molding the polyamide resin composition of any one of Claims 1-10.