JP5584963B2 - Polyamide resin composition - Google Patents

Description

  The present invention relates to a novel polyamide resin composition. Specifically, it is a polyamide resin composition in which a reinforcing fiber is blended with a polyamide resin whose dicarboxylic acid component is oxalic acid, and it has excellent chemical resistance and mechanical properties, but has a wide moldable temperature range and excellent moldability. In addition, the present invention relates to a polyamide resin composition in which reinforcing fibers are blended with a polyamide resin excellent in low water absorption and hydrolysis resistance.

  Crystalline polyamides such as nylon 6 and nylon 66 are widely used as clothing, industrial material fibers, or general-purpose engineering plastics because of their excellent properties and ease of melt molding. Problems such as changes in physical properties due to water absorption, acid, high-temperature alcohol, and deterioration in hot water have also been pointed out, and there is an increasing demand for polyamides with superior dimensional stability and chemical resistance.

  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. However, for example, a polyoxamide resin using 1,6-hexanediamine as a diamine component has a melting point (about 320 ° C.) higher than the thermal decomposition temperature (1% weight loss temperature in nitrogen; about 310 ° C.) (non-patent document). 1) Melt polymerization and melt molding were difficult and could not withstand practical use.

  For a polyoxamide resin whose diamine component is 1,9-nonanediamine (hereinafter abbreviated as PA92), L. Franco et al. Discloses a production method and its crystal structure when diethyl oxalate is used as the oxalic acid source ( Non-patent document 2). The PA 92 obtained here is a polymer having an intrinsic viscosity of 0.97 dL / g and a melting point of 246 ° C., but only a low molecular weight substance that cannot form a tough molded article is obtained. It is also shown that PA92 having an intrinsic viscosity of 0.99 dL / g and a melting point of 248 ° C. was produced when dibutyl oxalate was used as the dicarboxylic acid ester (Patent Document 2). In this case as well, there is a problem that only a low molecular weight body that cannot be formed into a tough molded body is obtained.

  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 3).

The present inventors use oxalic acid as a dicarboxylic acid component, and a polyamide resin using 1,9-nonanediamine and 2-methyl-1,8-octanediamine in a specific ratio as a diamine component has low water absorption, It was disclosed that it is a polyamide resin (PA92C) having a wide melt molding temperature range and excellent properties (Patent Document 4).
However, this polyamide resin uses oxalic acid as the dicarboxylic acid component, and has a specific ratio of three diamines of 1,9-nonanediamine, 2-methyl-1,8-octanediamine and 1,6-hexanediamine as the diamine component. It is not the polyoxamide resin used in 1.
SW Shalaby., J. Polym. Sci., 11, 1 (1973) L. Franco et al., Macromolecules., 31, 3912 (1988) JP 2006-57033 A Japanese National Patent Publication No. 5-506466 Patent 3036666 WO2008 / 072754

  The problem to be solved by the present invention is that a sufficiently high molecular weight is achieved, the moldable temperature range estimated from the difference between the melting point and the thermal decomposition temperature is wider, the melt moldability is excellent, and the aliphatic linear polyoxamide An object of the present invention is to provide a novel polyamide resin composition excellent in chemical resistance, flexibility, hydrolysis resistance and the like without impairing the low water absorption observed in the resin.

  As a result of intensive studies to solve the above problems, the present inventors have found that the dicarboxylic acid component is oxalic acid, and the diamine component is a mixture of 1,9-nonanediamine and 2-methyl-1,8-octanediamine. (Hereinafter also referred to as “C9 diamine mixture”) and 1,6-hexanediamine (hereinafter also referred to as “C6 diamine”), and the molar ratio of C9 diamine mixture to C6 diamine is 1:99 to 99: Surprisingly, the same as the polyamide resin (PA92C) previously disclosed in Patent Document 3 by the present inventors by blending reinforcing fibers with the polyamide resin 1 (hereinafter also referred to as “PA92 / 62T”). In addition, while having excellent mechanical properties and chemical resistance, it has a high molecular weight, a sufficiently large difference between the melting point and the thermal decomposition temperature, and excellent melt moldability. In addition to obtaining a polyamide resin composition that is superior in hydrolysis resistance as compared with conventional polyamides without impairing the low water absorption observed in the conventional resin, this novel polyamide resin (PA92 / 62T) Compared with PA92C, it has a higher melting point, better mechanical properties such as flexural modulus and deflection temperature under load, and is advantageous in terms of cost. As a result, the present invention was completed.

  The polyamide resin composition of the present invention is excellent in mechanical properties and chemical resistance, has low water absorption, can have a high molecular weight by melt polymerization, has a wide moldable temperature range of 50 ° C. or more, and 60 It is possible to use a wide range of molding materials such as industrial materials, industrial materials, and household goods. 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.

(1) Constituent Component of Polyamide Resin The polyamide used in the present invention has a dicarboxylic acid component composed of oxalic acid, and a diamine component comprising a mixture of 1,9-nonanediamine and 2-methyl-1,8-octanediamine (hereinafter referred to as “C9 diamine”). A polyamide resin having a molar ratio of the C9 diamine mixture to the C6 diamine of 1:99 to 99: 1. It is a polyamide resin composition (PA92 / 62T) characterized by including a material.

  As the oxalic acid source used in the production of the polyamide used in the present invention, oxalic acid diesters are used, and these are not particularly limited as long as they have reactivity with amino groups. Dimethyl oxalate, diethyl oxalate, di-n-oxalate (Or i-) propyl, oxalic acid diester of aliphatic monohydric alcohol such as di-n- (or i-, or t-) butyl oxalate, oxalic acid diester of alicyclic alcohol such as dicyclohexyl oxalate, aromatic such as diphenyl oxalate Examples include oxalic acid diester of alcohol.

  Among the above 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 preferred, and among them, dibutyl oxalate and diphenyl oxalate are particularly preferred.

  The molar ratio of the 1,9-nonanediamine component to the 2-methyl-1,8-octanediamine component in the C9 diamine mixture used in the polyamide resin of the present invention is generally 1:99 to 99: 1, preferably 5:95 to 95: 5, more preferably 5:95 to 40:60 or 60:40 to 95: 5, especially 5:95 to 30:70 or 70:30 to 90:10. By copolymerizing 1,9-nonanediamine, 2-methyl-1,8-octanediamine and 1,6-hexanediamine in the above specific amounts, the moldable temperature range is wide, the melt moldability is excellent, and the water absorption is low. Polyamide having excellent properties, chemical resistance, hydrolysis resistance, transparency and the like can be obtained.

  In the polyamide resin of the present invention, as the diamine component, the C9 diamine mixture (1,9-nonanediamine and 2-methyl-1,8-octanediamine) mixed with 1,6-hexanediamine is used. The molar ratio of C9 diamine mixture to 1,6-hexanediamine is 1:99 to 99: 1. By mixing 1,6-hexanediamine in a molar ratio of 1/99 or more with respect to the C9 diamine mixture, the above excellent effect of the polyamide resin (PA92C) comprising oxalic acid as the dicarboxylic acid component and C9 diamine mixture as the diamine component Can be maintained (particularly without impairing melt moldability and low water absorption), the melting point of the polyamide resin can be increased, and particularly the mechanical properties can be improved. The molar ratio of the C9 diamine mixture to 1,6-hexanediamine is preferably 5.1: 94.9 to 99: 1, more preferably 10:90 to 99: 1, and even more preferably 20:80 to 99: 1. It is. In particular, it is preferably 30:70 to 98: 2, and more preferably 30:70 to 90:10 (further 30:70 to 70:30). In this polyamide resin, the change to the melting point appears clearly by copolymerizing 1,6-hexanediamine in a molar ratio of 1/99 or more with respect to the C9 diamine mixture, and the melting point of the resin rises. If 6-hexanediamine is within a molar ratio of 99/1, an acceptable melt moldability can be obtained. If the molar ratio of 1,6-hexanediamine is within 80/20, the melting point of the polyamide resin will be 300 ° C. or lower, and polymerization and molding (melt moldability) will be easier, and within 70/30. It is more preferable because the melting point becomes 280 ° C. or lower and the melt moldability becomes easier.

(2) Manufacture of polyamide resin Polyamide resin PA92 / 62T used for this invention can be manufactured using the arbitrary methods known as a method of manufacturing polyamide. According to the study by the present inventors, it can be obtained by subjecting diamine and oxalic acid diester to a polycondensation reaction in a batch or continuous manner. Specifically, it is preferable to carry out in the order of (i) pre-polycondensation step and (ii) post-polycondensation step as shown by the following operations.

  (I) Pre-polycondensation step: First, the inside of the reactor is purged with nitrogen, and then diamine (diamine component) and oxalic acid diester (oxalic acid source) are mixed. When mixing, a solvent in which both the diamine and the oxalic acid diester are soluble may be used. The solvent in which both the diamine component and the oxalic acid source are soluble is not particularly limited, but toluene, xylene, trichlorobenzene, phenol, trifluoroethanol, and the like can be used, and particularly, toluene can be 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 of the oxalic acid diester and the diamine is oxalic acid diester / the diamine, 0.8 to 1.5 (molar ratio), preferably 0.91 to 1.1 (molar 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. In the temperature rising process, the final temperature of the prepolycondensation step, that is, from 80 to 150 ° C, is finally 220 ° C to 300 ° C, preferably 230 ° C to 280 ° C, more preferably 240 ° C to 270 ° C. Let reach the range. It is preferable to carry out the reaction for 1 to 8 hours including the temperature raising time, preferably 2 to 6 hours. Furthermore, in the post-polymerization step, polymerization can be performed under reduced pressure as necessary. The preferable final ultimate pressure in the case of performing the vacuum polymerization is less than 0.1 MPa to 13.3 Pa.

The specific example of the manufacturing method of the polyamide resin used for this invention is demonstrated.
First, the raw oxalic acid diester is charged into the container. The container is not particularly limited as long as it can withstand the temperature and pressure of the polycondensation reaction to be performed later. Thereafter, the container is heated to a temperature at which it is mixed with the raw material diamine, and then the diamine is injected to start the polycondensation reaction. The temperature at which the raw materials are mixed is not particularly limited as long as it is a temperature not lower than the boiling point and lower than the boiling point of the oxalic acid diester and diamine, and the polyoxamide generated by the polycondensation reaction of the oxalic acid diester and diamine is not thermally decomposed. For example, a mixture of 1,9-nonanediamine, 2-methyl-1,8-octanediamine, 1,6-hexanediamine, and C9 diamine (1,9-nonanediamine and 2-methyl-1,8-octanediamine) In the case of a polyoxamide resin using diamine and dibutyl oxalate as raw materials in a molar ratio of a mixture of 1,6-hexanediamine of 1:99 to 99: 1, the mixing temperature is preferably 15 ° C to 300 ° C. When the molar ratio of C9 diamine (a mixture of 1,9-nonanediamine and 2-methyl-1,8-octanediamine) and 1,6-hexanediamine is about 5:95 to 90:10, it is liquid at room temperature. Or it is more preferable because it is easy to handle because it liquefies only by heating to about 50 ° C. When the mixing temperature is equal to or higher than the boiling point of the alcohol produced by the condensation reaction, it is desirable to use a container equipped with a device for distilling and condensing the alcohol. In addition, when pressure polymerization is performed in the presence of an alcohol generated by a condensation reaction, a pressure vessel is used. The charging ratio of oxalic acid diester to diamine is oxalic acid diester / the above diamine, 0.8 to 1.2 (molar ratio), preferably 0.91 to 1.09 (molar ratio), more preferably 0.98 to 1. 0.02 (molar ratio).

  Next, the inside of the container is heated to a temperature not lower than the melting point of the polyoxamide resin and not higher than the temperature at which it does not decompose. For example, C9 diamine (a mixture of 1,9-nonanediamine and 2-methyl-1,8-octanediamine) and 1,6-hexanediamine, and C9 diamine (1,9-nonanediamine and 2-methyl-1, The molar ratio of the mixture of 8-octanediamine) and 1,6-hexanediamine is 50:50, and the molar ratio of 1,9-nonanediamine and 2-methyl-1,8-octanediamine is 50:50. In the case of a polyoxamide resin using diamine and dibutyl oxalate as raw materials, the melting point is 261 ° C., so it is preferable to raise the temperature from 270 ° C. to 300 ° C. (pressure is 2 MPa to 4 MPa). While distilling off the produced alcohol, the polycondensation reaction is continued under an atmospheric pressure of nitrogen or reduced pressure as necessary. When the raw materials are mixed in a pressure vessel and subjected to pressure polymerization in the presence of an alcohol produced by a condensation reaction, the pressure is first released while the produced alcohol is distilled off. Thereafter, the polycondensation reaction is continued under an atmospheric pressure of nitrogen or reduced pressure as necessary. The preferable final pressure in the case of carrying out the vacuum polymerization is 760 to 0.1 Torr. The temperature is preferably 270 to 300 ° C. The alcohol is cooled and liquefied by a water-cooled condenser and recovered.

(3) Properties and properties of polyamide resin There is no particular limitation on the molecular weight of the polyamide resin PA92C used in the present invention, but a solution containing 96% concentrated sulfuric acid as a solvent and a polyamide resin concentration of 1.0 g / dl is used at 25 ° C. The relative viscosity ηr measured in (1) is in the range of 1.8 to 6.0. Preferably it is 2.0-5.5, and 2.5-4.5 is especially preferable. If ηr is lower than 1.8, the molded product becomes brittle and the physical properties deteriorate. On the other hand, if ηr is higher than 6.0, the melt viscosity becomes high, and the molding processability deteriorates.

  The polyamide resin used in the present invention uses oxalic acid as the carboxylic acid component, and copolymerizes 1,9-nonanediamine and 2-methyl-1,8-octanediamine as the diamine component, whereby oxalic acid and 1,9-nonanediamine are copolymerized. It is possible to increase the relative viscosity, that is, increase the molecular weight as compared with the polyamide. The polyamide resin PA92 / 62T used in the present invention uses oxalic acid as the carboxylic acid component, and 1,9-nonanediamine and 2-methyl-1,8-octanediamine as the diamine component and further 1,6-hexamethylenediamine. By copolymerizing, it is possible to raise the melting point of the resin as compared with polyamides composed of succinic acid, 1,9-nonanediamine and 2-methyl-1,8-octanediamine.

(4) Reinforcing fiber The present invention is characterized in that a reinforcing fiber is blended with the above polyamide resin. However, the reinforcing fiber is not particularly limited, and includes glass fiber, carbon fiber, metal fiber, mineral fiber, and the like. Organic fibers such as inorganic fibers and 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.

  2-40 mass parts is suitable with respect to 100 mass parts of resin whole, 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 carbon fiber diameter is not limited, but is preferably 5 to 15 μm. Fine carbon fibers can also be used.

  The fiber length of the carbon fiber may be a short fiber or a long fiber depending on the use, but is preferably 5 to 1000 m.

  2-40 mass parts is suitable with respect to 100 mass parts of resin whole, 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.

(5) Inorganic particles Examples of inorganic particles that can be used in the present invention include particles of metals, metal oxides, inorganic compounds, and the like. Specifically, for example, 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 such as molybdenum sulfide , And the like.

  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.

(6) Other components that can be blended The polyamide resin PA92 / 62T used in the present invention can be mixed with other dicarboxylic acid components within a range that does not impair the effects of the present invention. Examples of dicarboxylic acid components other than succinic acid include malonic acid, dimethylmalonic acid, succinic acid, glutaric acid, adipic acid, 2-methyladipic acid, trimethyladipic acid, pimelic acid, 2,2-dimethylglutaric acid, 3, Aliphatic dicarboxylic acids such as 3-diethylsuccinic acid, azelaic acid, sebacic acid and suberic acid, alicyclic dicarboxylic acids such as 1,3-cyclopentanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid, and terephthalic acid , Isophthalic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,4-phenylenedioxydiacetic acid, 1,3-phenylenedioxydiacetic acid, dibenzoic acid Acid, 4,4′-oxydibenzoic acid, diphenylmethane-4,4′-dicarboxylic acid, diphenyls Hong-4,4'-dicarboxylic acid, 4,4'-biphenyl and the like alone aromatic dicarboxylic acids such as dicarboxylic acids, or may be added to any mixture thereof 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. In general, the amount of the dicarboxylic acid component other than oxalic acid is preferably 5 mol% or less based on the total dicarboxylic acid component.

  In addition, the polyamide resin PA92 / 62T used in the present invention can be mixed with other diamine components as long as the effects of the present invention are not impaired. As other diamine components other than 1,9-nonanediamine and 2-methyl-1,8-octanediamine, ethylenediamine, propylenediamine, 1,4-butanediamine, 1,8-octanediamine, 1,10-decanediamine 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, alicyclic diamines such as cyclohexanediamine, methylcyclohexanediamine, isophoronediamine, p-phenylenediamine, m-phenylenediamine, p-xylenediamine, m-xylene Diamine, 4,4'-diaminodiphenylmethane, 4 4'-diaminodiphenyl sulfone, 4,4'-aromatic diamines, such as diaminodiphenyl ether, etc. alone or can be added any mixture thereof during the polycondensation reaction. The blending amount of diamine components other than 1,9-nonanediamine and 2-methyl-1,8-octanediamine is generally preferably 5 mol% or less based on the total diamine components.

  In addition, the polyamide resin PA92 / 62T used in the present invention can be mixed with other polyoxamides, polyamides such as aromatic polyamides, aliphatic polyamides, and alicyclic polyamides, as long as the effects of the present invention are not impaired. is there.

  Furthermore, thermoplastic polymers other than polyamide, elastomers, and the like can be similarly blended. However, the novel polyamide resin PA92 / 62T used in the present invention is preferably contained in an amount of 50% by mass or more of the resin component.

  Furthermore, the polyamide resin composition of the present invention may be optionally provided with a filler, 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. Accelerators, glass fibers, plasticizers, lubricants and the like can be added during or after the polycondensation reaction.

(7) Molding process of polyamide resin composition As a molding method of the polyamide resin composition of the present invention, polyamide resin and reinforcing fibers are blended in advance, or reinforcing fibers are put in the middle of a molding machine, injection, extrusion, hollow All known molding methods that can be applied to polyamide resin compositions such as press, roll, foaming, vacuum / compression, stretching, etc. are possible and can be processed into films, sheets, molded articles, fibers, etc. by these molding methods. it can.

(8) Use of polyamide molded product A molded product using the fiber-reinforced polyamide resin composition of the present invention is useful in various applications because of its excellent characteristics, and a molded product of a polyamide resin composition has been conventionally used. Various molded products, sheets, films, pipes, tubes, monofilaments, fibers, containers, etc., automobile parts, computers and related equipment, optical equipment members, electrical / electronic equipment, information / communication equipment, precision equipment, civil engineering / building supplies, It can be used for a wide range of applications such as medical supplies and household products. 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) and crystallization temperature (Tc):
Tm and Tc were measured under a nitrogen atmosphere using a PYRIS Diamond DSC manufactured by PerkinELmer. The temperature was raised from 30 ° C. to 300 ° C. at a rate of 10 ° C./min (referred to as a temperature rise first run), held at 300 ° C. for 3 minutes, and then lowered to −100 ° C. at a rate of 10 ° C./min (temperature fall first). Then, the temperature was raised to 300 ° C. at a rate of 10 ° C./min (called a temperature rising second run). For the plasticizer-containing sample, the endothermic peak temperature of the temperature rising first run from the obtained DSC chart, and for the sample not containing the plasticizer, the endothermic peak temperature of the temperature rising second run is the exothermic peak temperature of the temperature decreasing first run. Temperature.

(3) 1% weight loss temperature (Td):
Td was measured by thermogravimetric analysis (TGA) using THERMOGRAVIMETRIC ANALYZER TGA-50 manufactured by Shimadzu Corporation. 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 under the conditions of 290 ° C. and shear rate of 0.1 s −1 in nitrogen by attaching a 25 mm cone plate to a melt viscoelasticity measuring device ARES manufactured by TA Instruments Japan.

(5) Film molding:
Film forming was performed using a vacuum press TMB-10 manufactured by Toho Machinery Co., Ltd. After 5 minutes of heating and melting at 290 ° C. in a reduced pressure atmosphere of 500 to 700 Pa (260 ° C. when nylon 6 is used, 290 ° C. when nylon 66 is used, 230 ° C. when nylon 12 is used), 5 MPa Was pressed 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 the polyamide hot press film obtained according to the present invention was immersed in the chemicals listed below for 7 days, the weight residual ratio (%) and changes in the appearance of the film were observed. In each of concentrated hydrochloric acid, 64% sulfuric acid, and glacial acetic acid solutions, tests were performed on samples immersed at 23 ° C.

(8) Hydrolysis resistance:
The polyamide hot press film obtained by the present invention was put in an autoclave, and each was 121 in water (pH = 7), 0.5 mol / l sulfuric acid (pH = 1), and 1 mol / l sodium hydroxide aqueous solution (pH = 14). The residual weight ratio (%) and the appearance change after the treatment at 60 ° C. for 60 minutes were examined.

(9) Mechanical properties:
In the following measurements [1] to [4], the following specimens were measured at a resin temperature of 290 ° C. (260 ° C. when nylon 6 was used, 290 ° C. when nylon 66 was used, and nylon 12 used. Was 230 ° C.) and was molded by injection molding at a mold temperature of 80 ° C. 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] Tensile test (tensile yield point strength): Measured in accordance with ASTM D638 using a Type I test piece described in ASTM D638.
[2] Bending test (flexural modulus): Measured at 23 ° C. in accordance with ASTM D790 using a test piece having dimensions of 127 mm × 12.7 mm × 3.2 mm.
[3] Izod impact strength: Measured at 23 ° C. in accordance with ASTM D256 using a test piece having dimensions of 127 mm × 12.7 mm × 3.2 mm.
[4] Deflection temperature under load: Measured at a load of 1.82 MPa in accordance with ASTM D648 using a test piece having a test piece size of 127 mm × 12.7 mm × 3.2 mm.

(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: PA92 / 62T-1]
Oxalic acid in 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 outlet, pressure regulator and polymer outlet The operation of charging 28.230 kg (139.56 mol) of dibutyl, pressurizing the inside of the pressure vessel to 0.5 MPa with nitrogen gas having a purity of 99.9999%, and then releasing nitrogen gas to normal pressure is performed 5 times. After repeated nitrogen substitution, the system was heated while stirring under a sealing pressure. After bringing the temperature of dibutyl oxalate to 100 ° C. over about 30 minutes, 1.241 kg (7.84 mol) of 1,9-nonanediamine and 19.639 kg (124.04 mol) of 2-methyl-1,8-octanediamine were obtained. ) And 0.893 kg (7.68 mol) of 1,6-hexanediamine (the molar ratio of 1,9-nonanediamine, 2-methyl-1,8-octanediamine and 1,6-hexanediamine is 5.62). : 88.88: 5.50) was supplied into the reaction vessel over about 17 minutes at a flow rate of 1.49 liters / minute by means of a diaphragm pump. 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 235 ° C. over 1 hour. 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 235 ° C., butanol was extracted from the pressure release 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, the temperature of the polycondensate was brought to 260 ° C. over about 1 hour, and the reaction was carried out at 260 ° C. for 4.5 hours. . Thereafter, stirring was stopped, the inside of the system was pressurized to 1 MPa with nitrogen and allowed to stand for about 10 minutes, then released to an internal pressure of 0.5 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 = 3.13.

[Production Example 2: PA92 / 62T-2]
28.462 kg (140.71 mol) of dibutyl oxalate was charged, 16.448 kg (103.88 mol) of 1,9-nonanediamine, 2.903 kg (18.34 mol) of 2-methyl-1,8-octanediamine and 1 , 6-hexanediamine 2.150 kg (18.50 mol) (mixture ratio of 1,9-nonanediamine, 2-methyl-1,8-octanediamine and 1,6-hexanediamine is 73.83: 13.13. 03: 13.14) was reacted in the same manner as in Production Example 1 to obtain polyamide. The obtained polyamide was a white tough polymer with ηr = 2.97.

[Production Example 3: PA92 / 62T-3]
30.238 kg (149.49 mol) of dibutyl oxalate was charged, 4.486 kg (28.33 mol) of 1,9-nonanediamine, 4.486 kg (28.33 mol) of 2-methyl-1,8-octanediamine and 1 , 6-hexanediamine 10.79 kg (92.85 mol) (1,9-nonanediamine, 2-methyl-1,8-octanediamine and 1,6-hexanediamine molar ratio of 18.95: 18. 95: 62.10) was supplied into the reaction vessel with a diaphragm pump at a flow rate of 1.49 liters / minute over about 17 minutes, and at the same time the temperature was raised. 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 270 ° C. over 1.5 hours. Meanwhile, the internal pressure was adjusted to 1.00 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. From the normal pressure, the temperature was raised while flowing nitrogen gas at 1.5 liters / minute, the temperature of the polycondensate was changed to 285 ° C. over about 1 hour, and the reaction was carried out at 285 ° C. for 1.5 hours. . Thereafter, stirring was stopped, the inside of the system was pressurized to 1 MPa with nitrogen and allowed to stand for about 10 minutes, then released to an internal pressure of 0.5 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 = 2.88.

[Production Example 4: PA92 / 62T-4]
29.864 kg (147.64 mol) of dibutyl oxalate was charged, and 5.598 kg (35.36 mol) of 1,9-nonanediamine, 5.598 kg (35.36 mol) of 2-methyl-1,8-octanediamine and 1 , 6-hexanediamine 8.941 kg (76.92 mol) of a mixture (the molar ratio of 1,9-nonanediamine, 2-methyl-1,8-octanediamine and 1,6-hexanediamine was 23.95: 23. 95: 52.10) was supplied to the reaction vessel by a diaphragm pump at a flow rate of 1.49 liters / minute over about 17 minutes, and at the same time the temperature was raised. 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 250 ° C. over 1 hour. Meanwhile, the internal pressure was adjusted to 1.00 MPa while extracting the generated butanol from the pressure relief port. Immediately after the temperature of the polycondensate reached 250 ° 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 increased to 270 ° C. over about 1 hour and reacted at 270 ° C. for 2 hours. Thereafter, stirring was stopped, the inside of the system was pressurized to 1 MPa with nitrogen and allowed to stand for about 10 minutes, then released to an internal pressure of 0.5 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 = 2.83.

[Production Example 5: PA92 / 62T-5]
29.107 kg (143.89 mol) of dibutyl oxalate was charged, 5.641 kg (35.63 mol) of 1,9-nonanediamine, 10.028 kg (63.34 mol) of 2-methyl-1,8-octanediamine and 1 , 6-hexanediamine 5.223 kg (44.93 mol) (1,9-nonanediamine, 2-methyl-1,8-octanediamine, 1,6-hexanediamine molar ratio 24.76: 44. 02: 31.22) was supplied into the reaction vessel over about 17 minutes at a flow rate of 1.49 liters / minute by means of a diaphragm pump, and the temperature was raised. 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 250 ° C. over 1 hour. 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 240 ° 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 adjusted to 265 ° C. over about 1 hour, and the reaction was carried out at 265 ° C. for 3 hours. Thereafter, stirring was stopped, the inside of the system was pressurized to 1 MPa with nitrogen and allowed to stand for about 10 minutes, then released to an internal pressure of 0.5 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 = 3.11.

[Reference Production Example 1: PA92C]
A mixture of 11.11 kg (70.2 mol) of 1,9-nonanediamine and 11.11 kg (70.2 mol) of 2-methyl-1,8-octanediamine was charged with 28.40 kg (140.4 mol) of dibutyl oxalate. Was supplied into the reaction vessel over about 17 minutes at a flow rate of 1.49 liters / minute by means of a diaphragm pump, and at the same time the temperature was raised. 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 235 ° C. over 1 hour. 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 235 ° C., butanol was extracted from the pressure release 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, the temperature of the polycondensate was brought to 260 ° C. over about 1 hour, and the reaction was carried out at 260 ° C. for 4.5 hours. . Thereafter, stirring was stopped, the inside of the system was pressurized to 1 MPa with nitrogen and allowed to stand for about 10 minutes, then released to an internal pressure of 0.5 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 = 3.35.

[Comparative Production Example 1: Production of PA92]
Using only 22.25 kg (140.4 mol) of 1,9-nonanediamine as a diamine raw material, a reaction was carried out in the same manner as in Production Example 1 to obtain a polyamide. The obtained polymer was a yellowish white polymer, and ηr = 2.78.

  Polyamide PA92 / 62T-1 to PA92 / 62T-5, PA92C, PA92, and nylon 6 (manufactured by Ube Industries, UBE nylon 1015B: PA6) produced in Production Examples 1-5, Reference Production Example 1 and Comparative Production Example 1. For nylon 66 (Ube Industries, UBE nylon 2020B: PA66) and nylon 12 (Ube Industries, UBESTA3020U: PA12), relative viscosity, melting point, crystallization temperature, 1% weight loss temperature, melt viscosity, saturated water absorption, resistance to water Chemical properties, hydrolysis resistance, mechanical properties in dry and wet conditions were measured. The results are shown in Table 1.

[Examples 1 to 12, Comparative Examples 1 to 4]
Polyamide PA92 / 62T-1 to PA92 / 62T-5, PA92C, PA-92, and nylon 6 (manufactured by Ube Industries, UBE nylon 1015B) manufactured in Production Examples 1 to 5, Reference Production Example 1 and Comparative Production Example 1. Nylon 66 (Ube Industries, UBE Nylon 2020B) and Nylon 12 (UBESTA3020U), Glass Fiber (Nippon Electric Glass ECST-289 (fiber diameter 13 μm), Carbon Fiber (Toho Tenax Co., Ltd. Best Fight HTA-C6NR (fiber) A mixture having a ratio shown in Table 2 was prepared using brass fibers (fiber diameter: 80 μm).

  Furthermore, the mixture was 290 ° C. using a biaxial kneader with a cylinder diameter of 40 mm (260 ° C. when nylon 6 was used, 290 ° C. when nylon 66 was used, and 230 ° C. when nylon 12 was used). The mixture was melt kneaded and extruded into a strand shape, cooled in a water tank, and then pelleted using a pelletizer. A predetermined test piece was prepared by injection molding using the obtained pellet.

  Using the resin composition and test piece obtained above, tensile strength, Izod impact, oxidation gasoline resistance, chemical resistance, calcium chloride resistance, melting point, 1% weight loss temperature were evaluated.

  The evaluation results are shown in Table 2.

  The fiber-reinforced polyamide resin composition of the present invention is excellent in low water absorption, chemical resistance, flexibility, hydrolysis resistance and the like, and excellent in melt molding processability without impairing mechanical strength. 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)

The carboxylic acid component consists of oxalic acid,
The diamine component is from a mixture of 1,9-nonanediamine and 2-methyl-1,8-octanediamine (hereinafter referred to as “C9 diamine mixture”) and 1,6-hexanediamine (hereinafter referred to as “C6 diamine”). Become
The molar ratio of the C9 diamine mixture and C6 diamine 1: 99 to 99: Ri 1 der,
C9 diamine mixture of 1,9, a molar ratio of 2-methyl-1,8-octane diamine 5:95 to 95: 5 der Ru polyamide resin, polyamide, characterized in that it contains an inorganic filler Resin composition.   The polyamide resin composition according to claim 1, wherein the inorganic filler is a reinforcing fiber and / or inorganic particles.   2. The polyamide resin has a relative viscosity (ηr) of 1.8 to 6.0 measured at 25 ° C. using a polyamide resin solution having a concentration of 1.0 g / dl using 96% sulfuric acid as a solvent. Or the polyamide resin composition of 2.   The polyamide resin is obtained by differential scanning calorimetry measured at a 1% weight loss temperature in a thermogravimetric analysis measured at a heating rate of 10 ° C./min in a nitrogen atmosphere and at a heating rate of 10 ° C./min in a nitrogen atmosphere. The polyamide resin composition according to claim 1, wherein the temperature difference from the measured melting point is 50 ° C. or more. The polyamide resin composition according to any one of claims 2 to 4 , wherein the reinforcing fibers are glass fibers and / or carbon fibers. The polyamide resin composition according to any one of claims 2 to 4 , wherein the inorganic particles are tungsten particles.