JP2013095792A - Filler-containing polyamide resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyamide resin composition whereby sufficient increase in molecular weight, a wide moldable temperature range estimated based on a difference between melting point and pyrolysis temperature, excellent melt-moldability, and high mechanical strength are achieved despite its low water absorbability, and, in comparison with a conventional aliphatic polyamide resin, excellent chemical resistance, hydrolysis resistance and the like are exhibited.SOLUTION: The polyamide resin composition, wherein a carboxylic acid component comprises an oxalic acid, and a diamine component comprises a mixture of 1,6-hexanediamine and 2-methyl-1,5-pentanediamine, with a polyamide resin having the 1,6-hexanediamine and 2-methyl-1,5-pentanediamine mixed at a molar ratio of 99:1 to 50:50 and including a filler.

Description

  The present invention relates to a novel polyamide resin composition. Specifically, it is a polyamide resin composition in which a filler is added to a polyamide resin in which the dicarboxylic acid component is oxalic acid and the diamine component is 1,6-hexanediamine and 2-methyl-1,5-pentanediamine, The present invention relates to a polyamide resin composition in which reinforcing fibers are blended with a polyamide resin having excellent chemical properties and mechanical properties, having a wide moldable temperature range, excellent moldability, low water absorption and hydrolysis resistance. Is.

Hereinafter, the name of the polyamide resin may be based on JIS K 6920-1.
Crystalline polyamides such as nylon 6 (PA6) and nylon 66 (PA66) are widely used as textiles for clothing, industrial materials, or general-purpose engineering plastics because of their excellent properties and ease of melt molding. However, on the other hand, problems such as changes in physical properties due to water absorption, acid, high-temperature alcohol, deterioration in hot water, etc. have been pointed out, and there is an increasing demand for polyamides with better dimensional stability and chemical resistance. ing.

  On the other hand, a polyamide resin using oxalic acid as a dicarboxylic acid component is called a polyoxamide resin, and is known to have a higher melting point and lower water absorption than other polyamide resins having the same amino group concentration (Patent Document 1). It is expected to be used in fields where the use of conventional polyamide, where the change in physical properties due to water absorption has been a problem, is difficult.

  So far, polyoxamide resins using various aliphatic linear diamines as diamine components have been proposed. For example, Non-Patent Document 1 discloses a polyoxamide resin using 1,6-hexanediamine as a diamine component, and Non-Patent Document 2 discloses a polyoxamide resin (hereinafter referred to as PA92) whose diamine component is 1,9-nonanediamine. Patent Document 2 discloses various diamine components and polyoxamide resin using dibutyl oxalate as a dicarboxylic acid ester. Patent Document 3 discloses 1,9-nonanediamine and 2-diamine as diamine components. A polyoxamide resin using two kinds of diamines of methyl-1,8-octanediamine in a specific ratio is disclosed.

  In applications where the usage conditions of parts made of polyamide resin are severe, depending on the application, for example, mechanical strength, fuel resistance (gasoline resistance, sour gasoline resistance, etc.), chemical resistance (antifreeze resistance) In addition to the above, there is a demand for improving the resistance to various chemicals (for example, Patent Document 4).

JP 2006-57033 A Japanese National Patent Publication No. 5-506466 WO2008 / 072754 Patent 3036666

S. W. Shalaby, J. et al. Polym. Sci. , 11, 1 (1973) L. Franco, et al. , Macromolecules, 31, 3912 (1998).

  However, since the melting point (about 320 ° C.) of the polyoxamide resin disclosed in Non-Patent Document 1 is close to the thermal decomposition temperature (1% weight loss temperature in nitrogen; about 310 ° C.), melt polymerization and melt molding are difficult. The polyoxamide resin disclosed in Non-Patent Document 2 discloses a production method and crystal structure of diethyl oxalate as a source of oxalic acid, and is obtained here. PA92 is a polymer having an intrinsic viscosity of 0.97 dL / g and a melting point of 246 ° C., and only a low molecular weight product that cannot be molded into a tough molded product has been obtained. Regarding the polyoxamide resin disclosed in Patent Document 2 Shows that PA92 having an intrinsic viscosity of 0.99 dL / g and a melting point of 248 ° C. has been produced, but only a low molecular weight product that cannot be molded into a tough molded product is obtained. In the polyoxamide resin disclosed in Patent Document 3, two kinds of diamines, 1,9-nonanediamine and 2-methyl-1,8-octanediamine, are used at a specific ratio as a diamine component. The polyoxamide resins used are shown, but these polyoxamide resins have a wide moldable temperature range, excellent molding processability, and excellent water absorption, chemical resistance, hydrolysis resistance, etc., but have a melting point of 240. The heat resistance is slightly inferior for electrical and electronic equipment applications that require a temperature of around ℃ and a molding cycle and a high melting point.

  In the above prior art documents, there is no specific disclosure of a polyoxamide resin using two kinds of diamines of 1,6-hexanediamine and 2-methyl-1,5-pentanediamine as a diamine component in a specific ratio.

  The problem to be solved by the present invention is that the melting point Tm (° C.) (hereinafter referred to as the melting point) measured by the differential scanning calorimetry measured at a temperature rising rate of 10 ° C./min in a nitrogen atmosphere as compared with the conventional polyoxamide resin Temperature difference (Td−Tm) (° C.) between 1% weight loss temperature Td (° C.) (thermal decomposition temperature) in thermogravimetric analysis measured at a heating rate of 10 ° C./min in a nitrogen atmosphere Provided is a polyamide resin composition having a wide moldable temperature range estimated from a temperature difference (hereinafter also referred to as temperature difference (Td−Tm)), excellent heat resistance and low water absorption estimated from a melting point Tm, and capable of reducing a molding cycle. (Problem 1), and in addition to the problem 1, without compromising the low water absorption seen in the aliphatic linear polyoxamide resin in the problem 1, compared with the conventional aliphatic polyamide resin assembly, chemical resistance It lies in (Problem 2) to provide a hydrolysis resistance with excellent polyamide resin composition.

As a result of intensive studies in order to solve the above problems, the present inventors have obtained a polyamide resin in which a unit derived from a dicarboxylic acid and a unit derived from a diamine are bonded, wherein the dicarboxylic acid is oxalic acid (compound a), wherein the diamine contains 1,6-hexanediamine (compound b) and 2-methyl-1,5-pentanediamine (compound c), and the molar ratio of the compound b to the compound c is 99: 1. By adding a filler to a polyamide resin (hereinafter also referred to as “PX6”) of ˜50: 50, the difference between the melting point and the thermal decomposition temperature is sufficiently large while having excellent mechanical properties and chemical resistance. A polyamide resin composition having excellent melt moldability and superior hydrolysis resistance as compared with conventional polyamide is obtained without impairing the low water absorption observed in linear polyoxamide resins. Heading to be, and have completed the present invention.
That is, the present invention is a polyamide resin composition comprising a polyamide resin (component A) and a filler (component B),
The component A is composed of a unit derived from a dicarboxylic acid and a unit derived from a diamine,
The dicarboxylic acid comprises oxalic acid (compound a);
The diamine comprises 1,6-hexanediamine (compound b) and 2-methyl-1,5-pentanediamine (compound c);
A polyamide resin composition having a molar ratio of the compound b to the compound c of 99: 1 to 50:50, and a molded body thereof.

According to the present invention,
Compared with the conventional polyoxamide resin, it is possible to provide a polyamide resin composition having a wide moldable temperature range estimated from the temperature difference (Td−Tm) and excellent in heat resistance estimated from the melting point Tm (Effect 1).
Furthermore, in addition to effect 1, chemical resistance and hydrolysis resistance can be achieved as compared with conventional aliphatic polyamide resin compositions without impairing the low water absorption seen in the aliphatic linear polyoxamide resin in effect 1. Can provide an excellent polyamide resin composition (Effect 2).
Therefore, the polyamide resin composition of the present invention is excellent in mechanical properties and chemical resistance, has low water absorption, a wide moldable temperature range of 25 ° C. or more, and further 60 ° C. or more. It is excellent in melt moldability and further in hydrolysis resistance, and can be widely used as a molding material for industrial materials, industrial materials, household products and the like. The chemical resistance of the polyamide resin composition of the present invention is excellent in anti-freezing properties, and the fuel resistance is excellent not only in gasoline but also in sour gasoline.

Hereinafter, the present invention will be described in detail.
[Polyamide resin (component A)]
(1) Configuration of Component A Component A, which is a polyamide resin in the present invention,
The dicarboxylic acid component is succinic acid and the diamine component consists of 1,6-hexanediamine and 2-methyl-1,5-pentanediamine,
A polyamide resin formed by bonding a unit derived from a dicarboxylic acid and a unit derived from a diamine,
The dicarboxylic acid comprises oxalic acid (compound a);
The diamine comprises 1,6-hexanediamine (compound b) and 2-methyl-1,5-pentanediamine (compound c);
The molar ratio of the compound b to the compound c is 99: 1 to 50:50,
Preferably, the relative viscosity ηr measured at 25 ° C. using a solution of Component A having a concentration of 1.0 g / dl in 96% sulfuric acid is 1.8 to 6.0.

  Component A is composed of compounds a, b and c, preferably a polycondensation using a mixture thereof, so that it has a high melting point, a large difference between the melting point and the thermal decomposition temperature, and excellent melt moldability. Without impairing the low water absorption observed in the polyoxamide resin, it is excellent in chemical resistance, hydrolysis resistance and fuel barrier properties as compared with conventional polyamide.

From the viewpoint of ensuring chemical resistance, hydrolysis resistance and fuel barrier properties, component A has a molar ratio of compound b to compound c:
Preferably, 99: 1 to 55:45 mol%,
More preferably, it is 99: 1-60: 40 mol%.
Hereinafter, the molar ratio of the compound b and the compound c also means the molar ratio of the unit derived from the compound b and the unit derived from the compound c in the component A.

When compound a (oxalic acid) is directly used as a raw material in the production of component A, compound a (succinic acid) itself is thermally decomposed, and the melting point of component A exceeds the thermal decomposition temperature. (Hereinafter, also referred to as oxalic acid source) and obtained by polycondensation of oxalic acid derived from the oxalic acid source and diamine. This oxalic acid is derived from an oxalic acid source such as oxalic acid diester, and any oxalic acid may be used as long as it has reactivity with an amino group.
As the oxalic acid source, oxalic acid diester is preferable from the viewpoint of suppressing side reactions in the polycondensation reaction. Dimethyl oxalate, diethyl oxalate, di-n- (or i-) propyl oxalate, di-n- (or i-, or t-) oxalate Examples thereof include oxalic acid diesters of aliphatic monohydric alcohols such as butyl, oxalic acid diesters of alicyclic alcohols such as dicyclohexyl oxalate, and oxalic acid diesters of aromatic alcohols such as diphenyl oxalate.
Among the oxalic acid diesters, oxalic acid diesters of aliphatic monohydric alcohols having more than 3 carbon atoms, oxalic acid diesters of alicyclic alcohols, and oxalic acid diesters of aromatic alcohols are more preferable,
Among them, dibutyl oxalate and diphenyl oxalate are more preferable,
More preferred is dibutyl oxalate.

(2) Relative viscosity of component A
Using oxalic acid as compound a as the carboxylic acid component,
As the diamine component, 1,6-hexanediamine as compound b and 2-methyl-1,5-pentanediamine as compound c are polycondensed so that the melting point is preferably in the range of 200 to 330 ° C. Compared to a polyamide resin obtained by polycondensation of compound a and compound b with a melting point exceeding 330 ° C. (hereinafter also referred to as comparative component A2), in the melt polymerization in the post-polymerization step of component A described later, Since it is not necessary to use an excessively high temperature condition in which a side reaction occurs and inhibits high molecular weight, high molecular weight (increasing relative viscosity) is possible.
Therefore, Component A has an excellent melt moldability because it can increase the relative viscosity as compared with the conventional polyamide resin.
In view of avoiding the tendency of the molded product after melt molding to become brittle and lowering the physical properties, to avoid the tendency to increase the melt viscosity at the time of melt molding and deteriorate the molding processability, the relative viscosity ηr and the melt viscosity are more than a certain level. From the viewpoint of being suitable for uses such as automobile parts and electrical / electronic parts that are preferably high and not excessively high, a 96% concentrated sulfuric acid solution having a concentration of component A of 1.0 g / dl is used. The relative viscosity ηr measured at 25 ° C. is
Preferably it is 1.8-6.0,
More preferably, it is 1.8-4.5,
More preferably, it is 1.8-3.0,
More preferably 1.85 to 2.5,
More preferably, it may be 1.85 to 2.2.
In the melt polymerization in the post-polymerization step of component A described later, the relative viscosity ηr can be increased by increasing the degree of vacuum.

From the same viewpoint, the melt viscosity of component A is
Preferably 100 to 700 Pa · s,
More preferably 110-600 Pa · s,
More preferably, 120 to 500 Pa · s,
More preferably, 130 to 400 Pa · s,
More preferably, 150 to 300 Pa · s,
More preferably, 160 to 220 Pa · s,
More preferably, it is 170-200 Pa.s,

Furthermore, from the same viewpoint, the number average molecular weight of component A is
Preferably it is 10000-50000,
More preferably, it is 11000-40000,
More preferably, it is 11000-35000.

The number average molecular weight (Mn) is based on the signal intensity obtained from the 1H-NMR spectrum, for example, dibutyl oxalate as the oxalic acid source, 1,6-hexanediamine (compound b) and 2-methyl-1, as the diamine component. In the case of a polyamide produced using 5-pentanediamine (compound c) at a molar ratio of 90:10 [hereinafter abbreviated as PX6-2 (compound b / compound c = 90/10)], it is calculated by the following formula. did.
Mn = np × 170.21 + n (NH ₂ ) × 115.20 + n (OBu) × 129.13 + n (NHCHO) × 29.14
In addition, the measurement conditions of 1H-NMR are as follows.
・ Model used: Bruker Biospin AVANCE500
-Solvent: Bisulfuric acid-Integration frequency: 1024 times Each term in the above formula is defined as follows.
Np = Np / [(N (NH ₂ ) + N (NHCHO) + N (OBu)) / 2]
・ N (NH ₂ )
= N (NH ₂ ) / [(N (NH ₂ ) + N (NHCHO) + N (OBu)) / 2]
・ N (NHCHO)
= N (NHCHO) / [(N (NH ₂ ) + N (NHCHO) + N (OBu)) / 2]
・ N (OBu)
= N (OBu) / [(N (NH ₂ ) + N (NHCHO) + N (OBu)) / 2]
Np = Sp / sp-N (NHCHO)
_{· N (NH2) = S (} NH 2) / s (NH 2)
N (NHCHO) = S (NHCHO) / s (NHCHO)
N (OBu) = S (OBu) / s (OBu)
However, each term has the following meaning.
Np: Total number of repeating units in the molecular chain excluding terminal units of PA62 (compound B / compound C = 90/10).
Np: the number of repeating units in the molecular chain per molecule.
Sp: PX6-2 (compound b / compound c = 90/10) excluding the signal based on the proton of the methylene group adjacent to the oxamide group in the repeating unit in the molecular chain (around 3.1 ppm) Integration value.
Sp: The number of hydrogens (4) counted in the integral value Sp.
* N (NH2): Total number of terminal amino groups of PX6-2 (compound b / compound c = 90/10).
N (NH2): number of terminal amino groups per molecule.
S (NH2): Integral value of a signal (around 2.6 ppm) based on the proton of the methylene group adjacent to the terminal amino group of PX6-2 (compound b / compound c = 90/10).
· S (NH2): integrated value S number of hydrogens counted in the (NH ₂₎ (2 pieces).
N (NHCHO): total number of terminal formamide groups of PX6-2 (compound b / compound c = 90/10).
N (NHCHO): number of terminal formamide groups per molecule.
-S (NHCHO): The integral value of the signal (7.8 ppm) based on the proton of the formamide group of PX6-2 (compound b / compound c = 90/10).
S (NHCHO): The number of hydrogens (one) counted in the integral value S (NHCHO).
N (OBu): the total number of terminal butoxy groups of PX6-2 (compound b / compound c = 90/10).
N (OBu): number of terminal butoxy groups per molecule.
S (OBu): integrated value of a signal (around 4.1 ppm) based on the proton of the methylene group adjacent to the oxygen atom of the terminal butoxy group of PX6-2 (compound b / compound c = 90/10).
S (OBu): The number of hydrogens (two) counted in the integral value S (OBu).

(3) Physical properties of component A Component A further changes the polycondensation ratio of compounds b and c,
The temperature difference (Td−Tm) is large compared to the comparative component A2, and small compared to the polyamide resin obtained by polycondensation of the compound a and the compound c (hereinafter also referred to as the comparative component A1).
The melting point Tm is low compared to the comparative component A2, high compared to the comparative component A1,
1% weight loss temperature Td is higher than the comparative component A1,
The saturated water absorption rate can be smaller than the comparative component A2 and larger than the comparative component A1.

That is, the component A is compared with the conventional polyoxamide resin,
Relative viscosity ηr (high molecular weight),
Moldable temperature range estimated from the temperature difference (Td−Tm),
Heat resistance estimated from melting point Tm,
Both melt moldability estimated from melt viscosity and low water absorption can be sufficiently secured.

  Component A has sufficient chemical resistance, resistance to resistance due to the high polymerization ratio (molar ratio) of compound b after sufficiently ensuring the moldable temperature range, heat resistance, melt moldability and low water absorption. Excellent hydrolyzability and fuel barrier properties.

From the viewpoint of sufficiently ensuring all of the moldable temperature range, heat resistance, melt moldability and low water absorption,
Tm is preferably 260 to 330 ° C, more preferably 265 to 330 ° C,
Td is preferably 341 to 370 ° C, more preferably 345 to 370 ° C, still more preferably 350 to 365 ° C,
The temperature difference (Td−Tm) is preferably 10 to 95 ° C., more preferably 20 to 95 ° C., still more preferably 25 to 95 ° C.,
The saturated water absorption is preferably 0 to 2.4, more preferably 1 to 2.4, still more preferably 2 to 2.4, and still more preferably 2.3 to 2.4.

(4) Production of Component A Component A can be produced using any method known as a method for producing polyamide, but from the viewpoint of high molecular weight and productivity,
Preferably, it is obtained by polycondensation reaction of diamine and oxalic acid diester batchwise or continuously.
More preferably, the diamine and the oxalic acid diester are obtained by a two-stage polymerization method comprising a pre-polycondensation step and a post-polycondensation step, or a pressure polymerization method described in WO2008-072754.
More preferable two-stage polymerization method and pressure polymerization method are specifically shown by the following operations.

(4-1) Two-stage polymerization method (i) Pre-polycondensation step: First, the inside of the reactor is purged with nitrogen, and then diamine (compounds b and c) and oxalic acid diester which is the oxalic acid source of compound a are mixed. When mixing, a solvent in which both the diamine and the oxalic acid diester are soluble may be used. As a solvent in which both the diamine component and the oxalic acid source component are soluble, toluene, xylene, trichlorobenzene, phenol, trifluoroethanol, and the like can be used, and toluene is particularly preferably used. For example, after heating the toluene solution which melt | dissolved diamine to 50 degreeC, oxalic acid diester is added with respect to this.
At this time, the charging ratio between the oxalic acid diester and the diamine is 0.8 to 1.5 (molar ratio), preferably 0.91 to 1.1 (molar ratio), from the viewpoint of increasing the molecular weight. Ratio), more preferably 0.99 to 1.01 (molar ratio).

  The temperature in the reactor charged in this way is increased under normal pressure while stirring and / or nitrogen bubbling. The reaction temperature is preferably controlled so that the final temperature reaches 80 to 150 ° C., preferably 100 to 140 ° C. The reaction time at the final temperature reached is 3-6 hours.

(Ii) Post-polycondensation step: In order to further increase the molecular weight, the polymer produced in the pre-polycondensation step is gradually heated in the reactor under normal pressure. From the final ultimate temperature of the pre-polycondensation step in the temperature rising process, that is, preferably from 80 to 150 ° C., finally,
The temperature is preferably 295 ° C. or higher and 350 ° C. or lower, more preferably 298 ° C. or higher and 345 ° C. or lower, more preferably 298 ° C. or higher and 340 ° C. or lower.
It is preferable to carry out the reaction while keeping the temperature rising time preferably 1 to 8 hours, more preferably 2 to 6 hours. Furthermore, in the post-polymerization step, polymerization can be performed under reduced pressure as necessary. A preferable final pressure in the case of carrying out the vacuum polymerization is 13.3 Pa to 0.1 MPa.

(4-2) Pressurized polymerization method First, diamine is placed in a pressure vessel and purged with nitrogen, and then heated to the reaction temperature under a sealing pressure. Thereafter, the oxalic acid compound is injected into the pressure vessel while maintaining the sealed pressure state at the reaction temperature, and the polycondensation reaction is started. The reaction temperature is not particularly limited as long as the polyamide produced by the reaction of the diamine and the oxalic acid compound can maintain a slurry or solution state and does not thermally decompose. For example, in the case of Component a, the reaction temperature is preferably 150 ° C to 250 ° C. Here, the charging ratio of dibutyl oxalate and diamine is 0.8 to 1.5 (molar ratio), preferably 0.91 to 1.1 (molar ratio), in terms of the molar amount of dibutyl oxalate / total molar amount of diamine. More preferably, it is 0.99 to 1.01 (molar ratio).
Next, while maintaining the inside of the pressure vessel in a sealed pressure state, the temperature is raised to a temperature not lower than the melting point of the polyamide resin and not pyrolyzed. For example, in the case of Component a, since the melting point is 245 to 300 ° C., the temperature is raised to 250 to 350 ° C., preferably 255 to 340 ° C., more preferably 260 to 335 ° C. The pressure in the pressure resistant container until reaching the predetermined temperature is adjusted to approximately 0.1 MPa, preferably 1 MPa to 0.2 MPa from the saturated vapor pressure of the alcohol to be generated. After reaching the predetermined temperature, the pressure is released while distilling off the produced alcohol, and the polycondensation reaction is continued under normal pressure nitrogen flow or reduced pressure as necessary. A preferable final pressure in the case of carrying out the vacuum polymerization is 13.3 Pa to 0.1 MPa.

(6) Component which can be used as dicarboxylic acid in component A In component A, other dicarboxylic acid components other than compound a can be used within a range not impairing the effects of the present invention.
As other dicarboxylic acid components other than compound a (oxalic acid),
Malonic acid, dimethylmalonic acid, succinic acid, glutaric acid, adipic acid, 2-methyladipic acid, trimethyladipic acid, pimelic acid, 2,2-dimethylglutaric acid, 3,3-diethylsuccinic acid, azelaic acid, sebacic acid , Aliphatic dicarboxylic acids such as suberic acid,
In addition, alicyclic dicarboxylic acids such as 1,3-cyclopentanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid,
Further, terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,4-phenylenedioxydiacetic acid, 1,3-phenylenedioxydi Aromatic dicarboxylic acids such as acetic acid, dibenzoic acid, 4,4′-oxydibenzoic acid, diphenylmethane-4,4′-dicarboxylic acid, diphenylsulfone-4,4′-dicarboxylic acid, 4,4′-biphenyldicarboxylic acid These may be added alone, or any mixture thereof may be added during the polycondensation reaction.
Furthermore, polyvalent carboxylic acids such as trimellitic acid, trimesic acid, and pyromellitic acid can be used as long as melt molding is possible.
When other dicarboxylic acid components are used, the proportion thereof is 25 mol% or less, preferably 15 mol% or less, more preferably 10 mol% or less, and more preferably 5 mol% or less with respect to compound a (succinic acid). More preferably, it is more preferably 0 mol% (that is, the dicarboxylic acid component consists only of compound a). The molar ratio of the other dicarboxylic acid component to the compound a (succinic acid) also means the molar ratio of the unit derived from the compound a and the unit derived from the other dicarboxylic acid component in the component A.

In component A, other diamine components other than compounds b and c can be used within the range not impairing the effects of the present invention.
As other diamine components other than 1,6-hexanediamine and 2-methyl-1,5-pentanediamine, ethylenediamine, propylenediamine, 1,4-butanediamine, 1,9-nonanediamine, 2-methyl-1, 8-octanediamine, 1,8-octanediamine, 1,10-decanediamine, 1,11-undecanediamine,
1,12-dodecanediamine, 3-methyl-1,5-pentanediamine, 2,2,4-trimethyl-1,6-hexanediamine, 2,4,4-trimethyl-1,6-hexanediamine, 5- Aliphatic diamines such as methyl-1,9-nonanediamine,
Furthermore, alicyclic diamines such as cyclohexanediamine, methylcyclohexanediamine, and isophoronediamine,
Furthermore, aromatic diamines such as p-phenylenediamine, m-phenylenediamine, p-xylenediamine, m-xylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfone, 4,4'-diaminodiphenylether ,
These may be added alone, or any mixture thereof may be added during the polycondensation reaction.
When other diamine components are used, the proportion thereof is 25 mol% or less, preferably 15 mol% or less, more preferably 10 mol% or less, still more preferably 5 mol% or less, with respect to compounds b and c. More preferably, it is 0 mol% (that is, the diamine component consists only of compounds b and c). In addition, the molar ratio of the other diamine component with respect to the compounds b and c also means the molar ratio of the units derived from the compounds b and c and the units derived from the other diamine components in the component A.

[Filler (component B)]
As the filler (component B), inorganic and / or organic fillers can be used, and inorganic fillers are preferred. The shape of the filler (component B) is arbitrary, and includes fibrous, particulate and the like. Examples of the filler (component B) include reinforcing fibers and / or inorganic particles. Although the compounding quantity of a filler is suitably set according to a use, it is 2-500 mass parts with respect to 100 mass parts of the whole polyamide resin, for example.
The reinforcing fiber is not particularly limited, and examples thereof include inorganic fibers such as glass fibers, carbon fibers, metal fibers, and mineral fibers, and organic fibers such as aramid fibers that are tougher than polyamide resins. By blending the reinforcing fibers, the effect of improving the physical properties such as the strength and creep resistance of the composition is remarkable. Glass fiber and carbon fiber are particularly preferable.

  The glass fiber is not particularly limited. The glass fiber diameter is not limited, but is preferably 5 to 15 μm. The fiber length may be a short fiber or a long fiber depending on the use, but is preferably 5 to 1000 μm. The glass fiber may be crushed by blending or processing, but the crushed glass fiber preferably has the fiber length.

  2-40 mass parts is suitable with respect to 100 mass parts of the whole polyamide resin, as for the mixture ratio of glass fiber, 2-38 mass parts is more preferable, and 3-35 mass parts is preferable. If the blending amount of the glass fiber is small, the improvement in rigidity and creep resistance is lowered, and the bonding with a tube or the like may be deteriorated. On the other hand, when the compounding amount of the glass fiber is increased, the fluidity of the composition is deteriorated, which may cause a short shot or the surface state.

The carbon fibers are not particularly limited, such as pitch-based and PAN-based, but PAN-based carbon fibers are preferable in terms of properties such as physical properties and conductivity.
The fiber length before kneading of the carbon fiber may be a long fiber extending up to 1000 mm in addition to that of the short fiber depending on the use, but in the case of melt kneading for the purpose of pellet production,
Preferably it is 0.1-12 mm, more preferably 1-8 mm,
The fiber diameter before kneading of the carbon fibers is preferably 5 to 15 μm, and carbon fibers having a finer fiber diameter can also be used.

  2-40 mass parts is suitable with respect to 100 mass parts of the whole polyamide resin, as for the mixture ratio of carbon fiber, 2-38 mass parts is more preferable, and 3-35 mass parts is preferable. If the blending amount of carbon fiber is small, the improvement in rigidity, creep resistance, and conductivity may be lowered, so 5 parts by mass or more is preferable. On the other hand, when the blending amount of the carbon fiber exceeds 40 parts by mass, the fluidity of the composition is deteriorated, which may cause a short shot and the surface state may be deteriorated.

  The polyamide resin used in the present invention has excellent mechanical strength, chemical resistance, low water absorption, hydrolysis resistance, etc., has a wide moldable temperature range, and excellent melt moldability. In the case of blending, basically, it is held as it is, and certain properties such as mechanical strength and heat resistance are remarkably improved by blending the reinforcing fibers.

  Examples of the inorganic particles that can be used in the present invention include particles of metals, metal oxides, inorganic compounds, and the like, which can be appropriately selected depending on the application. The particle size of the inorganic particles is not particularly limited and can be appropriately selected depending on the application. Specific examples of inorganic particles include metals such as tungsten, iron, zinc, tin, lead and copper, metal alloys such as tungsten copper and tungsten silver, metal oxides such as iron oxide and zinc oxide, and sulfides. Examples of the particles include sulfides such as molybdenum.

For example, in the use of a molded product having a high specific gravity using the polyamide resin composition of the present invention, inorganic particles having a density of 5 g / cm ³ or more, such as tungsten particles, can be preferably used. For example, in the application of a resin magnet using the polyamide resin composition of the present invention, magnetic particles such as ferrite such as barium ferrite and strontium ferrite, and rare earth magnetic materials such as samarium-cobalt and neodymium-iron-boron are used. It can be preferably used.

  The inorganic particles may be used alone or in combination of two or more, and may be subjected to surface treatment. Examples of the surface treatment include surface treatment with a titanate coupling agent, surface treatment with a silane surface treatment agent, and the like. The surface treatment with a titanate coupling agent is described in, for example, the known technique described in the above-mentioned JP-A-2-255760, and the surface treatment with a silane-based surface treatment agent is described in, for example, the above-mentioned JP-A-10-158507. Any known method can be employed.

  In the present invention, the mass ratio of the above-mentioned polyamide resin and inorganic particles may be within the range of 50/50 to 5/95, more preferably 20/80 to 5/95 for polyamide resin / inorganic particles, In this case, it is possible to more easily provide characteristics such as higher specific gravity and magnetism.

  The resin composition of the present invention includes, if necessary, other polyamides other than component A, such as polyoxamide, aromatic polyamide, aliphatic polyamide and alicyclic polyamide, in order to utilize the characteristics of each polymer. At least one polyamide selected from the group consisting of and / or polymers outside the polyamide, such as thermoplastic polymers and elastomers, can be included.

  The polymer other than component A is not particularly limited as long as it does not impair the effects of the present invention, but is preferably 0 to 50 parts by mass, more preferably 0 to 40 parts by mass, and still more preferably, relative to 100 parts by mass of component A. Is 0-30 parts by mass.

  Further, the polyamide resin composition of the present invention may optionally contain a stabilizer such as a copper compound, a colorant, an ultraviolet absorber, a light stabilizer, an antioxidant, an antistatic agent, a flame retardant, and a crystallization accelerator. Glass fiber, plasticizer, lubricant and the like can be added during or after the polycondensation reaction.

[Molding process of polyamide resin composition]
As a method for molding the polyamide resin composition of the present invention, polyamide resin and filler are blended in advance, or the filler is introduced in the middle of the molding machine, such as injection, extrusion, hollow, press, roll, foaming, vacuum, All known molding methods applicable to the polyamide resin composition, such as compressed air and stretching, are possible, and can be processed into films, sheets, molded articles, fibers and the like by these molding methods.

[Use of molded product of polyamide resin composition]
Molded articles using the polyamide resin composition of the present invention are useful in various applications because of their excellent characteristics, and various molded articles, sheets, films, and pipes in which the molded article of the polyamide resin composition has been conventionally used. , Tubes, monofilaments, fibers, containers, etc. for a wide range of applications such as automobile parts, computers and related equipment, optical equipment parts, electrical / electronic equipment, information / communication equipment, precision equipment, civil engineering / building equipment, medical supplies, household goods Can be used. In particular, since it is reinforced, it is useful for applications such as automobiles and electrical / electronic devices.

[Physical property measurement, molding, evaluation method]
Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto.
In addition, the measurement in an Example was performed with the following method.

(1) Relative viscosity (ηr):
ηr was measured at 25 ° C. using an Ostwald viscometer using a 96% polyamide sulfuric acid solution (concentration: 1.0 g / dl).

(2) Melting point (Tm):
Tm was measured under a nitrogen atmosphere using a PYRIS Diamond DSC manufactured by PerkinELmer.
Tm of Production Examples 1 and 2, Comparative Production Example 1, Examples 1 to 4 and Examples 10 to 12 were raised from 30 ° C. to 350 ° C. at a rate of 10 ° C./min (referred to as a temperature rise first run). , Held at 350 ° C. for 3 minutes, then cooled to −100 ° C. at a rate of 10 ° C./min (referred to as a first temperature drop), and then increased to 350 ° C. at a rate of 10 ° C./min (temperature increase second) Called a run).
Tm of Production Examples 3 to 5, Examples 5 to 9 and Comparative Examples 1 to 2 was increased from 30 ° C. to 310 ° C. at a rate of 10 ° C./min (referred to as a temperature rising first run), and 3 at 310 ° C. After maintaining the minute, the temperature was lowered to −100 ° C. at a rate of 10 ° C./min (referred to as a temperature fall first run), and then the temperature was raised to 310 ° C. at a rate of 10 ° C./min (referred to as a temperature rise second run).
The endothermic peak temperature of the elevated temperature second run was defined as Tm.

(3) 1% weight loss temperature (Td):
Td is THERMOGRAVIMETRIC ANALYZER TG made by Shimadzu Corporation
Measurement was performed by thermogravimetric analysis (TGA) using A-50. The temperature was raised from room temperature to 500 ° C. at a rate of 10 ° C./min under a nitrogen stream of 20 ml / min, and Td was measured.

(4) Melt viscosity:
The melt viscosity was measured by attaching a 25 mm cone plate to a melt viscoelasticity measuring device ARES manufactured by TA Instruments Japan, and in nitrogen, 300 ° C. (Production Examples 3 to 5), 340 ° C. (Production Example 1) ˜2, Comparative Production Example 1), when nylon 6 was used, measurement was performed under the conditions of 260 ° C., when nylon 66 was used, 290 ° C. and shear rate of 0.1 s ⁻¹ .

(5) Film molding:
Film forming was performed using a vacuum press TMB-10 manufactured by Toho Machinery Co., Ltd. 300 degreeC (manufacture examples 3-5, examples 5-9, and comparative examples 1-2), 340 degreeC (manufacture examples 1-2, comparative manufacture example 1, examples 1-4, and implementation) under reduced pressure atmosphere of 500-700 Pa Examples 10-12) When nylon 6 was used, it was heated and melted at 260 ° C. and when nylon 66 was used at 290 ° C. for 5 minutes, and then pressed at 5 MPa for 1 minute to form a film. Next, the reduced-pressure atmosphere was returned to normal pressure, and then cooled and crystallized at room temperature of 5 MPa for 1 minute to obtain a film.

(6) Water absorption rate (saturated water absorption rate, equilibrium water absorption rate):
A film (dimensions: 20 mm × 10 mm, thickness 0.25 mm; weight about 0.05 g) obtained by molding the polyamide resin under the conditions of (5) is immersed in ion exchange water at 23 ° C., and the film is taken out every predetermined time. The weight of the film was measured. When the rate of increase in the film weight lasts 3 times within a range of 0.2% or less, it is determined that the absorption of water into the polyamide resin film has reached saturation, and the weight of the film before being immersed in water (Xg) From the weight (Yg) of the film when reaching saturation, the saturated water absorption (%) was calculated by the formula (1).

Saturated water absorption (%) = 100 (Y−X) / X (1)

The water absorption rate (equilibrium water absorption rate) calculated by the formula (1) from the weight (Yg) immediately after forming the film and the weight (Yg) when the film reached equilibrium at a humidity of 65% and a temperature of 23 ° C. ) As the wet water absorption.

(7) Chemical resistance:
After immersing a press film obtained by molding the polyamide resin under the condition (5) in the chemicals listed below for 7 days, changes in the weight residual ratio (%) and appearance of the film were observed. Tests were conducted on samples immersed in concentrated hydrochloric acid, 64% sulfuric acid, 30% NaOH aqueous solution, and 5% K ₂ MnO ₄ at 23 ° C. and benzyl alcohol at 50 ° C.

(8) Hydrolysis resistance:
A press film obtained by molding the polyamide resin under the condition (5) is put in an autoclave, and in water (pH = 7), 0.5 mol / l sulfuric acid (pH = 1), 1 mol / l sodium hydroxide aqueous solution (pH = 14). Were examined for residual weight (%) and appearance change after treatment at 121 ° C. for 60 minutes.

(9) Mechanical properties:
The following [1]-[3] measurements are carried out using the following test pieces at a resin temperature of 300 ° C. (Production Examples 1 to 3, Examples 5 to 9 and Comparative Examples 1 and 2), 340 ° C. (Production Examples 1 to 2). 2. Comparative production example 1, Examples 1 to 4 and Examples 10 to 12), 260 ° C. when nylon 6 is used, 290 ° C. when nylon 66 is used, and injection molding at a mold temperature of 80 ° C. And using this. The ones evaluated at 23 ° C. without conditioning immediately after molding are shown in the table as dry, and the ones evaluated at 23 ° C. after conditioning at a humidity of 65% and a temperature of 23 ° C. after molding are shown in the table.
[1] Bending test (flexural modulus): Measured at 23 ° C. in accordance with ASTM D790 using a test piece having a test piece size of 127 mm × 12.7 mm × 3.2 mm.
[2] Deflection temperature under load: Measured with a load of 1.82 MPa in accordance with ASTM D648 using a test piece with a test piece size of 127 mm × 12.7 mm × 3.2 mm.
[3] Tensile test (tensile strength): Measured according to ASTM D638 using a Type I test piece described in ASTM D638.

(10) Calcium chloride resistance:
The film molded under the condition (5) was immersed in a saturated calcium chloride aqueous solution at 23 ° C. After one day, the appearance of the film was visually observed to evaluate the presence or absence of cracks.

(11) Oxidation resistance to gasoline:
An oxidized gasoline solution obtained by adding 0.1 g of tert-butyl peroxide and 0.01 g of copper stearate to a mixed solution of 600 ml of toluene and 600 ml of isooctane is adjusted to 60 ° C., and 30 specimens for tensile testing are contained therein. The solution was changed every week, and the change in physical properties (tensile strength) for 30 days was measured.

[Production Example 1: Polyamide resin (A): PX6-1]
A pressure vessel with an internal volume of about 150 liters equipped with a stirrer, thermometer, torque meter, pressure gauge, raw material inlet directly connected to the diaphragm pump, nitrogen gas inlet, pressure relief port, pressure regulator and polymer outlet , 6-hexanediamine 15.407 kg (132.58 mol) and 2-methyl-1,5-pentanediamine 811.1 g (6.98 mol) (1,6-hexanediamine and 2-methyl-1, Operation in which the molar ratio of 5-pentanediamine is 95: 5), the inside of the pressure vessel is pressurized to 0.5 MPa with nitrogen gas having a purity of 99.9999%, and then the nitrogen gas is released to normal pressure. Was repeated 5 times, and after nitrogen substitution, the system was heated while stirring under a sealing pressure. After the temperature of dibutyl oxalate was raised to 80 ° C. over about 30 minutes, 28.230 kg (139.56 mol) of dibutyl oxalate was placed in the reaction vessel over about 17 minutes at a flow rate of 1.49 liters / minute with a diaphragm pump. The temperature was raised simultaneously with the supply to The internal pressure in the pressure vessel immediately after the supply increased to 0.35 MPa by butanol generated by the polycondensation reaction, and the temperature of the polycondensate increased to about 170 ° C. Thereafter, the temperature was raised to 330 ° C. over 2 hours. Meanwhile, the internal pressure was adjusted to 0.75 MPa while extracting the generated butanol from the pressure relief port. Immediately after the temperature of the polycondensate reached 330 ° C., butanol was extracted from the pressure relief port over about 20 minutes, and the internal pressure was brought to normal pressure. From the normal pressure, the temperature was raised while flowing nitrogen gas at 1.5 liters / minute, and the reaction was carried out for 4.5 hours. Thereafter, the stirring was stopped and the system was pressurized to 1 MPa with nitrogen and allowed to stand for about 10 minutes. Then, the pressure was released to an internal pressure of 0.1 MPa, and the polycondensate was extracted in a string form from the lower outlet of the pressure vessel. The string-like polymer was immediately cooled with water, and the water-cooled string-like resin was pelletized with a pelletizer. The obtained polyamide was a white tough polymer with ηr = 1.95.

[Production Example 2: Polyamide resin (A): PX6-2]
A mixture of 14.717 kg (126.64 mol) of 1,6-hexynediamine and 1.635 kg (14.07 mol) of 2-methyl-1,5-pentanediamine (1,6-hexanediamine and 2-methyl-1, Polyamide was obtained by carrying out the reaction in the same manner as in Production Example 1 except that the molar ratio of 5-pentanediamine was 90:10) and 28.462 kg (140.71 mol) of dibutyl oxalate was charged. The obtained polyamide was a white tough polymer with ηr = 2.05.

[Production Example 3: Polyamide resin (A): PX6-3]
A mixture of 12.16 kg (104.64 mol) of 1,6-hexanediamine and 5.212 kg (44.85 mol) of 2-methyl-1,5-pentanediamine (1,6-hexanediamine and 2-methyl-1, The molar ratio of 5-pentanediamine is 70:30), and 30.238 kg (149.49 mol) of dibutyl oxalate is fed into the reaction vessel through a diaphragm pump at a flow rate of 1.49 liters / minute for about 17 minutes. At the same time, the temperature rose. The internal pressure in the pressure vessel immediately after the supply increased to 0.35 MPa by butanol generated by the polycondensation reaction, and the temperature of the polycondensate increased to about 170 ° C. Thereafter, the temperature was raised to 290 ° C. over 1.5 hours. Meanwhile, the internal pressure was adjusted to 0.5 MPa while extracting the generated butanol from the pressure relief port. Immediately after the temperature of the polycondensate reached 290 ° C., butanol was extracted from the pressure relief port over about 20 minutes, and the internal pressure was brought to normal pressure. Starting from normal pressure, the temperature was raised while flowing nitrogen gas at 1.5 liters / minute, the temperature of the polycondensate was brought to 310 ° C. over about 1 hour, and the reaction was carried out at 310 ° C. for 1.5 hours. . Thereafter, the stirring was stopped and the system was pressurized to 1 MPa with nitrogen and allowed to stand for about 10 minutes. Then, the pressure was released to an internal pressure of 0.1 MPa, and the polycondensate was extracted in a string form from the lower outlet of the pressure vessel. The string-like polymer was immediately cooled with water, and the water-cooled string-like resin was pelletized with a pelletizer. The obtained polyamide was a white tough polymer with ηr = 2.40.

[Production Example 4: Polyamide resin (A): PX6-4]
A mixture of 10.294 kg (88.583 mol) of 1,6-hexanediamine and 6.863 kg (59.057 mol) of 2-methyl-1,5-pentanediamine (1,6-hexanediamine and 2-methyl-1 , 5-pentanediamine in a molar ratio of 60:40), and 29.864 kg (147.64 mol) of dibutyl oxalate was placed in the reaction vessel with a diaphragm pump at a flow rate of 1.49 liters / minute for about 17 minutes. The temperature was raised simultaneously with the supply. The internal pressure in the pressure vessel immediately after the supply increased to 0.35 MPa by butanol generated by the polycondensation reaction, and the temperature of the polycondensate increased to about 170 ° C. Thereafter, the temperature was raised to 275 ° C. over 1.5 hours. Meanwhile, the internal pressure was adjusted to 0.5 MPa while extracting the generated butanol from the pressure relief port. Immediately after the temperature of the polycondensate reached 270 ° C., butanol was extracted from the pressure release port over about 20 minutes, and the internal pressure was brought to normal pressure. The temperature was raised from normal pressure while flowing nitrogen gas at 1.5 liters / minute, the temperature of the polycondensate was changed to 290 ° C. over about 1 hour, and the reaction was carried out at 290 ° C. for 2 hours. Thereafter, the stirring was stopped and the system was pressurized to 1 MPa with nitrogen and allowed to stand for about 10 minutes. Then, the pressure was released to an internal pressure of 0.1 MPa, and the polycondensate was extracted in a string form from the lower outlet of the pressure vessel. The string-like polymer was immediately cooled with water, and the water-cooled string-like resin was pelletized with a pelletizer. The obtained polyamide was a white tough polymer, and ηr = 2.68.

[Production Example 5: Polyamide resin (A): PX6-5]
A mixture of 8.361 kg (71.947 mol) of 1,6-hexanediamine and 8.361 kg (71.947 mol) of 2-methyl-1,5-pentanediamine (1,6-hexanediamine and 2-methyl-1) , 5-pentanediamine in a molar ratio of 50:50), and 29.107 kg (143.89 mol) of dibutyl oxalate was placed in the reaction vessel with a diaphragm pump at a flow rate of 1.49 liters / minute for about 17 minutes. The temperature was raised simultaneously with the supply. The internal pressure in the pressure vessel immediately after the supply increased to 0.35 MPa by butanol generated by the polycondensation reaction, and the temperature of the polycondensate increased to about 170 ° C. Thereafter, the temperature was raised to 260 ° C. over 1.5 hours. Meanwhile, the internal pressure was adjusted to 0.5 MPa while extracting the generated butanol from the pressure relief port. Immediately after the temperature of the polycondensate reached 260 ° C., butanol was extracted from the pressure release port over about 20 minutes, and the internal pressure was brought to normal pressure. The temperature was raised from normal pressure while flowing nitrogen gas at 1.5 liters / minute, and the temperature of the polycondensate was changed to 275 ° C. over about 1 hour, and the reaction was carried out at 275 ° C. for 3 hours. Thereafter, the stirring was stopped and the system was pressurized to 1 MPa with nitrogen and allowed to stand for about 10 minutes. Then, the pressure was released to an internal pressure of 0.1 MPa, and the polycondensate was extracted in a string form from the lower outlet of the pressure vessel. The string-like polymer was immediately cooled with water, and the water-cooled string-like resin was pelletized with a pelletizer. The obtained polyamide was a white tough polymer, and ηr = 2.61.

[Comparative Production Example 1: Polyamide resin: PX6-6]
(I) Pre-polycondensation step: The inside of a 1 L separable flask equipped with a stirrer, a reflux condenser, a nitrogen inlet tube, and a raw material inlet is replaced with nitrogen gas having a purity of 99.9999%.
500 ml of dehydrated toluene,
1,6-hexanediamine 58.7209 g (0.5053 mol) was charged.
After this separable flask was placed in an oil bath and heated to 50 ° C,
Dibutyl oxalate (102.1956 g, 0.5053 mol) was charged.
Next, the temperature of the oil bath was raised to 130 ° C., and the reaction was carried out for 5 hours under reflux.
Note that all operations from preparation of raw materials to completion of the reaction were performed under a nitrogen stream of 50 ml / min.

(Ii) Post-polycondensation step: The prepolymer obtained by the above operation is charged into a glass reaction tube having a diameter of about 35 mmφ equipped with a stirrer, an air cooling tube, and a nitrogen introduction tube. Then, the operation of introducing nitrogen gas to normal pressure was repeated 5 times, and then the mixture was transferred to a salt bath maintained at 290 ° C. under a nitrogen stream of 50 ml / min. After the temperature of the salt bath was set to 340 ° C. over 1 hour, the pressure in the container was reduced to about 66.5 Pa, and the reaction was further continued for 2 hours.
Subsequently, after introducing nitrogen gas to normal pressure, it was removed from the salt bath and cooled to room temperature under a nitrogen stream of 50 ml / min to obtain a polyamide resin. The obtained polymer was a yellow polymer, and ηr = 1.65.

(Test Example 1)
Production Examples 1-5, Polyamides PX6-1 to PX6-6 produced in Comparative Production Example 1, and nylon 6 (Ube Industries, UBE nylon 1015B: PA6) and nylon 66 (Ube Industries, UBE nylon 2020B: PA66) The relative viscosity, melting point, 1% weight loss temperature, melt viscosity, saturated water absorption, chemical resistance, hydrolysis resistance, and mechanical properties in dry and wet conditions were measured. The results are shown in Table 1.

[Examples 1-12, Comparative Examples 1-2]
Polyamides PX6-1 to PX6-5 produced in Production Examples 1 to 5, nylon 6 (Ube Industries, UBE nylon 1015B) and nylon 66 (Ube Industries, UBE nylon 2020B), and glass fiber (Nippon Electric Glass) Using ECST-289 (fiber diameter 13 μm), carbon fiber (Toho Tenax Co., Ltd., Besphite HTA-C6NR (fiber diameter 7 μm), brass fiber (fiber diameter 80 μm), a mixture having the ratio shown in Table 2 was prepared. .

  Furthermore, the mixture was used a biaxial kneader with a cylinder diameter of 40 mm, resin temperatures of 300 ° C. (Examples 5 to 9), 340 ° C. (Examples 1 to 4 and Examples 10 to 12), and nylon 6 were used. In this case, the mixture was melt-kneaded at 260 ° C. and nylon 266 at 290 ° C., extruded into a strand, cooled in a water tank, and then pelletized using a pelletizer. A predetermined test piece was prepared by injection molding using the obtained pellet.

[Examples 13 to 22, Comparative Examples 3 to 4]
Polyamides PX6-1 to PX6-5 produced in Production Examples 1 to 5 and Nylon 6 (manufactured by Ube Industries, UBE nylon 1015B), strontium ferrite having an average particle size of 10 μm and surface treated with an aminosilane coupling agent, aminosilane coupling Mixtures having the ratios shown in Tables 3 and 4 were prepared using tungsten powder having an average particle diameter of 10 μm and surface-treated with an agent.

Furthermore, these mixtures were mixed using a biaxial kneader having a cylinder diameter of 40 mm, and the resin temperature was 300 ° C. (Examples 14, 19, 21), 340 ° C. (Examples 13, 15, 16, 17, 18, 20, 22). When nylon 6 was used, it was melt-kneaded at 260 ° C., extruded into a strand shape, cooled in a water tank, and then pelletized using a pelletizer. A predetermined test piece was prepared by injection molding using the obtained pellet.
In addition, the polyamide resin composition using PX6-6 could not be melt-kneaded and molded because Td-Tm was small.

(12) Density Density was measured using ASTM No. 1 piece according to ASTM D792.

(13) Calcium chloride resistance (cycle)
An ASTM No. 1 test piece was used and immersed in water at 80 ° C. for 8 hours as a pretreatment. Next, after conditioning for 1 hour in an 80 ° C. and 85% RH constant temperature and humidity chamber, a saturated calcium chloride aqueous solution was applied to the test piece and heat treated in a 100 ° C. oven for 1 hour. The humidity control and heat treatment were repeated as one cycle up to 30 cycles, and the number of cycles in which the test piece cracked was used as an index.

(14) Zinc chloride resistance (cycle)
An ASTM No. 1 test piece was used and immersed in water at 80 ° C. for 8 hours as a pretreatment. Next, after conditioning for 1 hour in an 80 ° C. and 85% RH constant temperature and humidity chamber, a saturated zinc chloride aqueous solution was applied to the test piece and heat treated in a 100 ° C. oven for 1 hour. The humidity control and heat treatment were repeated as one cycle up to 30 cycles, and the number of cycles in which the test piece cracked was used as an index.

(15) Methanol resistance (mass change during methanol immersion)
Using ASTM No. 1 piece, it was immersed in methanol for 21 days, and the mass change was calculated from the mass before and after the immersion.

(Test Example 2)
Using the resin composition and test piece obtained above, tensile strength, tensile strength after oxidation-resistant gasoline treatment, saturated water absorption, and calcium chloride resistance were evaluated.

  The evaluation results are shown in Table 2.

  Using the resin composition and test piece obtained above, density, saturated water absorption, calcium chloride resistance (cycle), zinc chloride resistance (cycle), and mass change during methanol immersion were evaluated. The results are shown in Tables 3 and 4.

  The polyamide resin composition of the present invention is excellent in low water absorption, chemical resistance, flexibility, hydrolysis resistance, etc. without impairing mechanical strength, and excellent in melt molding processability. It can be suitably used as a molding material for industrial materials, industrial materials, household goods and the like. For example, it can be used in various applications such as automobile parts, optical equipment members, electrical / electronic equipment, information / communication related equipment, precision equipment, civil engineering / building supplies, medical supplies, and household goods as various injection molded products.

Claims (6)

A polyamide resin composition comprising a polyamide resin (component A) and a filler (component B),
The component A is composed of a unit derived from a dicarboxylic acid and a unit derived from a diamine,
The dicarboxylic acid comprises oxalic acid (compound a);
The diamine comprises 1,6-hexanediamine (compound b) and 2-methyl-1,5-pentanediamine (compound c);
The polyamide resin composition whose molar ratio of the said compound b and the said compound c is 99: 1-50: 50.   The polyamide resin composition according to claim 1, wherein the filler (component B) is a reinforcing fiber and / or inorganic particles.   The polyamide resin composition according to claim 2, wherein the reinforcing fibers are glass fibers and / or carbon fibers.   The polyamide resin composition according to claim 2, wherein the inorganic particles are tungsten particles.   The polyamide resin composition according to claim 2, wherein the inorganic particles are magnetic particles.   The molded object of the polyamide resin composition of any one of Claims 1-5.