JP2009298864A - Injection-molding material containing new polyamide resin - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an injection-molding material, as compared with the injection-molding materials such as nylon 6, etc., having less warp, excellent in dimensional stability, chemical resistance and hydrolysis resistance, having a wider moldable temperature width than those of the materials using 1,9-nonane diamine singly as a diamine component, excellent in melt moldability and capable of making further higher molecular weight to be able to produce a tough molded article. <P>SOLUTION: The injection-molding material contains a polyamide resin of which the dicarboxylic acid component consists of oxalic acid, and the diamine component consists of the 1,9-nonane diamine and 2-methyl-1,8-octane diamine, and having a (1:99) to (99:1) molar ratio of the 1,9-nonane diamine to the 2-methyl-1,8-octane diamine. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an injection molding material containing a novel polyamide resin composition. Specifically, it is an injection molding material with less warpage, excellent dimensional stability, chemical resistance and hydrolysis resistance compared to injection molding materials such as nylon 6, and 1,9-nonanediamine as a diamine component. The present invention relates to an injection molding material that has a wider moldable temperature range than a material using a simple substance, is excellent in melt moldability, and can produce a tough injection molded body that can have a high molecular weight.

  Crystalline polyamides represented by nylon 6, nylon 66 and the like are widely used as materials for clothing, industrial materials, or general-purpose engineering plastics because of their excellent characteristics and ease of melt molding. 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 a need for a polyamide resin having lower water absorption and excellent chemical resistance and the polyamide resin. It is growing.

  Crystalline polyamides are preferably sufficiently crystallized in order to exhibit their characteristics. However, crystalline polyamides such as nylon 6 and nylon 66 generally have a low crystallization rate, and depending on molding conditions. There is a problem in that the crystallization of the polyamide during molding is insufficient, the crystallization of the polyamide occurs after molding, and the dimensional stability is poor. Therefore, there is a demand for a polyamide resin having a high crystallization speed and excellent dimensional stability even when molded under various molding conditions and a molded body produced using the polyamide resin.

  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). In addition, it is expected to be used in fields where conventional polyamides are difficult to use due to changes in physical properties due to water absorption.

  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 (hereinafter abbreviated as PA92) whose diamine component is 1,9-nonanediamine, L. Franco et al. Discloses a production method and 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. In addition, JP-A-5-506466 discloses 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 the prior literature, there was no specific disclosure of a polyoxamide resin using two kinds of diamines of 1,9-nonanediamine and 2-methyl-1,8-octanediamine as a diamine component in a specific ratio.

JP 2006-57033 A Special table 5-506466

S. W. Shalaby., J. Polym. Sci., 11, 1 (1973) L. Franco et al., Macromolecules., 31, 3912 (1988)

  The present invention has been made on the basis of the above circumstances, and the present invention has less warpage, excellent dimensional stability, and excellent chemical resistance and hydrolysis resistance compared to injection molding materials such as nylon 6. To produce a tough injection-molded material that is an injection-molded material and has a wider moldable temperature range, better melt moldability, and higher molecular weight than a material that uses 1,9-nonanediamine alone as a diamine component. It is an object of the present invention to provide an injection molding material that can be used.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that from oxalic acid diester as the oxalic acid source, 1,9-nonanediamine and 2-methyl-1,8-octanediamine as the diamine component. It has been found that the above-mentioned problems can be solved by using the resulting polyamide resin as a molding material, and the present invention has been completed.

Specifically, the present invention relates to the following aspects.
[Aspect 1]
The dicarboxylic acid component consists of oxalic acid, the diamine component consists of 1,9-nonanediamine and 2-methyl-1,8-octanediamine, and the moles of 1,9-nonanediamine and 2-methyl-1,8-octanediamine An injection molding material comprising a polyamide resin having a ratio of 1:99 to 99: 1.

[Aspect 2]
Aspect 1 in which the relative viscosity (ηr) measured at 25 ° C. using a polyamide resin solution having a concentration of 1.0 g / dl using 96% sulfuric acid as a solvent is 1.8 to 6.0. The injection molding material as described in.
[Aspect 3]
1% weight loss temperature in thermogravimetric analysis of the polyamide resin measured at a temperature rising rate of 10 ° C./min in a nitrogen atmosphere, and differential scanning calorimetry measured at a temperature rising rate of 10 ° C./min in a nitrogen atmosphere. The injection molding material according to aspect 1 or 2, wherein the temperature difference from the melting point measured by the step is 50 ° C or higher.

[Aspect 4]
The injection molding material according to any one of aspects 1 to 3, wherein the molar ratio of 1,9-nonanediamine to 2-methyl-1,8-octanediamine is 5:95 to 95: 5.
[Aspect 5]
An injection molded article produced from the injection molding material according to any one of aspects 1 to 4.

  The injection molding material of the present invention is an injection molding material with less warpage, superior dimensional stability, excellent chemical resistance and hydrolysis resistance as compared with injection molding materials such as nylon 6, and as a diamine component. It is possible to produce a tough molded body having a wider moldable temperature range and excellent melt moldability than that of a material using 1,9-nonanediamine alone, and having a higher molecular weight.

Hereinafter, the present invention will be described in detail.
[Polyamide resin]
In the polyamide resin used in the present invention, the dicarboxylic acid component is composed of oxalic acid, the diamine component is composed of 1,9-nonanediamine and 2-methyl-1,8-octanediamine, and 1,9-nonanediamine and 2-methyl- The molar ratio with 1,8-octanediamine is 1:99 to 99: 1.

  As the oxalic acid source as the dicarboxylic acid source of the polyamide resin used in the present invention, oxalic acid diester is used, and there is no particular limitation as long as it has reactivity with an amino group. Dimethyl oxalate, diethyl oxalate, oxalic acid Di-n- (or i-) propyl, oxalic acid diesters of aliphatic monohydric alcohols such as di-n- (or i-, or t-) butyl oxalate, oxalic acid diesters of alicyclic alcohols such as dicyclohexyl oxalate, diphenyl oxalate, etc. And oxalic acid diesters of aromatic alcohols.

  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 preferred, and among them, dibutyl oxalate and diphenyl oxalate are particularly preferred.

  In the polyamide resin used in the present invention, oxalic acid is used as the dicarboxylic acid source, but other dicarboxylic acid components can be blended 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, diphenylsulfuric acid Down-4,4'-dicarboxylic acid, 4,4'-biphenyl dicarboxylic acid aromatic dicarboxylic acids such as such alone or may be added any mixtures thereof during the polycondensation reaction. Furthermore, polycarboxylic acids such as trimellitic acid, trimesic acid, and pyromellitic acid can be used within a range where melt molding is possible.

  The blending amount of the other dicarboxylic acid is not particularly limited as long as the effects of the present invention are not impaired. In general, it is preferably 5 mol% or less with respect to the total amount of the dicarboxylic acid.

  As the diamine component, 1,9-nonanediamine and 2-methyl-1,8-octanediamine are used. The molar ratio of the 1,9-nonanediamine component to the 2-methyl-1,8-octanediamine component is 1:99 to 99: 1, preferably 5:95 to 95: 5. By copolymerizing a specific amount of 1,9-nonanediamine and 2-methyl-1,8-octanediamine, a polyamide having a high molecular weight and a high melt viscosity can be obtained as compared with a conventional polyamide.

Furthermore, the molar ratio of 1,9-nonanediamine to 2-methyl-1,8-octanediamine is preferably, for example, 5:95 to 40:60 or 60:40 to 95: 5, and 5: It is particularly preferred that it is 95-30: 70 or 70: 30-90: 10.
When the molar ratio is 5:95 to 40:60, particularly 5:95 to 30:70, the crystallinity is excellent, so that low water absorption and mechanical properties are excellent, and liquid and / or vapor (for example, , Alcohol) has low permeability, and more water absorption than the case where the molar content of 1,9-nonanediamine is higher than the molar content of 2-methyl-1,8-octanediamine. There is an advantage that it is low. On the other hand, when the molar ratio is 60:40 to 95: 5, particularly 70:30 to 90:10, there is an advantage that low water absorption and mechanical properties are more excellent and excellent transparency is imparted. .

  The polyamide resin used in the present invention uses 1,9-nonanediamine and 2-methyl-1,8-octanediamine as the diamine component, but other diamine components are used as long as the effects of the present invention are not impaired. Can be blended. Examples of diamine components other than 1,9-nonanediamine and 2-methyl-1,8-octanediamine include ethylenediamine, propylenediamine, 1,4-butanediamine, 1,6-hexanediamine, and 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, aliphatic diamines such as 5-methyl-1,9-nonanediamine, cyclohexanediamine, methylcyclohexanediamine, and cycloaliphatic diamines such as isophoronediamine, p-phenylenediamine, m-phenylenediamine, p -Xylenediamine, m-xylenediamine, 4,4'-diamy Diphenylmethane, 4,4'-diaminodiphenyl sulfone, 4,4'-aromatic diamines diaminodiphenyl ether or the like, etc. alone, or can be added any mixture thereof during the polycondensation reaction.

  Although it will not specifically limit if it is a range which does not impair the effect of this invention as a compounding quantity of said other diamine component, It is preferable that it is 5 mol% or less with respect to the total amount of a diamine component.

[Production method of polyamide resin]
The polyamide resin used in the present invention can be produced by any method known as a method for producing polyamide. According to the study by the present inventors, it is preferable to polymerize the polyamide resin 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).

  While stirring and / or nitrogen bubbling in the reactor charged with the above raw materials, the temperature is raised under normal pressure. 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.

  Next, 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 that is not lower than the melting 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, it consists of a mixture of 1,9-nonanediamine and 2-methyl-1,8-octanediamine, and the molar ratio of 1,9-nonanediamine and 2-methyl-1,8-octanediamine is 1:99 to 99: In the case of a polyoxamide resin using diamine 1 and dibutyl oxalate as raw materials, the mixing temperature is preferably 15 ° C to 240 ° C. Moreover, since the molar ratio of 1,9-nonanediamine and 2-methyl-1,8-octanediamine is 5:95 to 90:10, it is liquid at room temperature or liquefied only by heating to about 40 ° C. It is more preferable because it is easy to handle. 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 and diamine is oxalic acid diester / diamine as described above, 0.8 to 1.2 (molar ratio), preferably 0.91 to 1.09 (molar ratio), more preferably 0.98. -1.02 (molar ratio).

  Subsequently, 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 no thermal decomposition occurs. For example, a diamine and shu comprising 1,9-nonanediamine and 2-methyl-1,8-octanediamine, and the molar ratio of 1,9-nonanediamine and 2-methyl-1,8-octanediamine is 85:15. In the case of a polyoxamide resin using dibutyl acid as a raw material, the melting point is 235 ° C., so it is preferable to raise the temperature from 240 ° C. to 280 ° 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 240 to 280 ° C. The alcohol is cooled and liquefied by a water-cooled condenser and recovered.

  The molecular weight of the polyamide resin used in the present invention is 1.0 to 6.0 g, more preferably 2.0 to 5 relative viscosity ηr measured at 25 ° C. using a 1.0 g / dl 96% concentrated sulfuric acid solution. .5, particularly preferably having a molecular weight in the range of 2.5 to 4.5. If the molecular weight is low, the melt viscosity tends to be low and not suitable for hollow molding. On the other hand, when the molecular weight increases, the melt viscosity increases and the melt moldability tends to deteriorate.

  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, so that oxalic acid and 1,9-nonanediamine are copolymerized. The relative viscosity can be increased, that is, the molecular weight can be increased as compared with the polyamide made of The moldable temperature range represented by the difference (Td−Tm) between the 1% weight loss temperature (hereinafter abbreviated as Td) and the melting point (hereinafter abbreviated as Tm), which is a substantial thermal decomposition index, is oxalic acid. And a polyamide composed of 1,9-nonanediamine, preferably 50 ° C. or higher, more preferably 60 ° C. or higher, and even 90 ° C. or higher. The polyamide resin used in the present invention has a Td of preferably 280 ° C. or higher, more preferably 300 ° C. or higher, still more preferably 320 ° C. or higher, and has high heat resistance.

[Injection molding material]
The dicarboxylic acid component consists of oxalic acid, the diamine component consists of 1,9-nonanediamine and 2-methyl-1,8-octanediamine, and the moles of 1,9-nonanediamine and 2-methyl-1,8-octanediamine Polyamide resins having a ratio of 1:99 to 99: 1 are included.
In this specification, the term “injection molding material” means a material for producing an injection molded body.

The injection molding material of the present invention can further include the following components as optional components in addition to the polyamide resin.
(1) Other polymer The dicarboxylic acid component used in the present invention is composed of oxalic acid, the diamine component is composed of 1,9-nonanediamine and 2-methyl-1,8-octanediamine, and 1,9-nonanediamine and 2- The polyamide resin having a molar ratio with methyl-1,8-octanediamine of 1:99 to 99: 1 can be partially substituted with other polymer components as long as the effects of the present invention are not impaired. Examples of other polymer components include other polyamides such as polyoxamide, aromatic polyamide, aliphatic polyamide, alicyclic polyamide, and polymers other than polyamide, such as thermoplastic polymers and elastomers.

Although it will not specifically limit if it is the range which does not impair the effect of this invention as said substitution ratio by said other polymer, Preferably it is less than 50 mass%, More preferably, it is 30 mass% or less.
In the following, when simply referred to as “polyamide” or “polyamide resin”, the dicarboxylic acid component consists of oxalic acid, the diamine component consists of 1,9-nonanediamine and 2-methyl-1,8-octanediamine, And it shall refer to the polyamide resin whose molar ratio of 1,9-nonanediamine and 2-methyl-1,8-octanediamine is 1: 99-99: 1.

(2) Additive The injection molding material of the present invention can contain other additives as long as the effects of the present invention are not impaired. Other additives include, for example, pigments, dyes, colorants, heat resistance agents, antioxidants, weathering agents, UV absorbers, light stabilizers, lubricants, crystal nucleating agents, crystallization accelerators, mold release agents, and charging agents. Examples thereof include stabilizers, plasticizers, stabilizers such as copper compounds, antistatic agents, flame retardants, glass fibers, lubricants, fillers, reinforcing fibers, reinforcing particles, and foaming agents.

  The method for adding the other polymer and the additive is not particularly limited as long as each of them can be dispersed in the polyamide resin, and the polyamide resin can be added to the polyamide resin at any time without impairing its effect. Can be added. For example, the other polymers and additives can be added immediately after the post polycondensation step of the polyamide resin.

(3) Layered silicate The injection molding material of the present invention can produce an injection-molded product with little warpage and excellent dimensional stability with only the above-mentioned polyamide resin, but more precise dimensional stability is required. In use, the injection molding material of the present invention can further include a layered silicate.
Further, by adding a layered silicate, it is possible to improve the rigidity, weather resistance and / or heat resistance, and barrier properties against liquids or vapors of an injection molded product produced from the injection molding material of the present invention.

  The layered silicate is preferably a flat plate having a side length of 0.002 to 1 μm and a thickness of 6 to 20 mm. Moreover, it is preferable that the said layered silicate is a thing disperse | distributed uniformly, each layer maintaining the interlayer distance of about 20 mm or more in the above-mentioned polyamide resin.

  Here, “interlayer distance” refers to the distance between the centroids of the plate-like layered silicate, and “uniformly dispersed” means that each layer exists mainly in a random state, and the layered silicate 50% by mass or more, preferably 70% by mass or more, is dispersed in a single layer without forming a multilayer.

  The amount of the layered silicate is not particularly limited as long as the effect of the layered silicate is exhibited, but is preferably 0.05 to 10 with respect to 100 parts by mass of the polyamide resin described above. It is 0.05 parts by mass, more preferably 0.05-8 parts by mass, particularly preferably 0.05-5 parts by mass. When the ratio of the layered silicate is lowered, the effect of the layered silicate is not exhibited, and when the ratio is increased, the melt viscosity becomes extremely high, so that the moldability is deteriorated or the impact resistance is lowered. There is.

  Examples of the raw material for the layered silicate include layered phyllosilicate minerals composed of magnesium silicate or aluminum silicate layers, that is, aluminum silicate phyllosilicate or magnesium silicate phyllosilicate. Specific examples include smectite clay minerals such as montmorillonite, saponite, beidellite, nontronite, hectorite, and stevensite, vermiculite, and halloysite. It may be what was done.

  Moreover, in order to disperse the layered silicate in the polyamide resin, a swelling agent is usually used. The swelling agent has a role of expanding the interlayer of the clay mineral and a role of giving the clay mineral a force for taking up the interlayer polymer. In the present invention, it is preferable to use 1,9-nonanediamine and 2-methyl-1,8-octanediamine as the swelling agent.

  The layered silicate is preferably pulverized using a mixer, a ball mill, a vibration mill, a pin mill, a jet mill, a beating machine, or the like to have a desired shape and size in advance.

  The method for adding the layered silicate is not particularly limited as long as the layered silicate can be uniformly dispersed in the polyamide resin. For example, when the raw material of the layered silicate is a multilayered clay mineral, as disclosed in JP-A-62-74957, the layered silicate is ionized with hydrochloric acid or the like, and a swelling agent such as, for example, 1,9-nonanediamine and 2-methyl-1,8-octanediamine are added to widen the space between the layers of the layered silicate in advance. Next, a polyamide raw material can be introduced between the layers, and the raw materials can be polymerized between the layers.

  Alternatively, an organic compound may be used as a swelling agent, and the layers may be preliminarily spread to about 100 mm or more and melt-mixed with the polyamide resin to disperse each layer in the polyamide resin.

[Injection molded body]
The injection-molded article of the present invention can be produced by molding an injection molding material in combination with not only injection molding but also, for example, extrusion molding, blow molding, compression molding, injection molding and the like.
The injection molded body is not particularly limited, but is a molded body that has little warpage and is required to have excellent dimensional stability, for example, parts with complicated shapes, such as oil tanks for two- and four-wheeled vehicles, intake system parts. , And integrated parts thereof, electrical component cases, and other molded articles suitable for manufacturing containers and the like.
In the present specification, the injection-molded body includes a welding and bonding member.

  More specifically, as the injection molded body, for example, an intake system module integrating an intake system component such as an intake manifold of an automobile, which requires high strength and durability, a cylinder head cover, an intake manifold, an air cleaner, and the like. Examples include parts, cooling system parts such as water inlets and water outlets, fuel system parts such as fuel injection and fuel delivery pipes, containers such as oil tanks, and electrical equipment cases such as switches.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated, this invention is not limited to these Examples.

[Physical property measurement, molding, evaluation method]
The characteristic value was measured by the following method.
(1) Relative viscosity (ηr)
ηr was measured at 25 ° C. with an Ostwald viscometer using a 96% sulfuric acid solution of polyamide (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 270 ° C. at a rate of 10 ° C./min (referred to as a temperature rise first run), held at 270 ° 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 270 ° C. at a rate of 10 ° C./min (called a temperature raised second run). From the obtained DSC chart, the exothermic peak temperature of the temperature decrease first run was Tc, and the endothermic peak temperature of the temperature increase second run was Tm.

(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 Melt viscosity was measured by attaching a 25 mm cone plate to a melt viscoelasticity measuring device ARES manufactured by TA Instruments Japan Co., Ltd., at 250 ° C. in nitrogen and at a shear rate of 0.1 s ⁻¹ . Measured under conditions.

(5) Film formation A film was formed from the pellets using a vacuum press TMB-10 manufactured by Toho Machinery Co., Ltd. After being melted by heating at 260 ° C. (resin temperature: 290 ° C. for PA66) for 5 minutes in a reduced pressure atmosphere of 500 to 700 Pa, the film was formed by pressing at 5 MPa for 1 minute. 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) Saturated water absorption rate A film (dimensions: 20 mm × 10 mm, thickness 0.25 mm; mass of about 0.05 g) formed under the conditions of (5) above is immersed in ion-exchanged water at 23 ° C., and every predetermined time. The film was taken out and the mass of the film was measured. When the rate of increase in the film mass lasts 3 times within the range of 0.2%, it is judged that the absorption of moisture into the polyamide resin film has reached saturation, and the mass (Xg) of the film before being immersed in water The saturated water absorption (%) was calculated from the mass (Yg) of the film when reaching saturation with the following equation (1).
Saturated water absorption (%) = 100 × (Y−X) / X (1)

(7) Chemical Resistance After immersing the polyamide hot press film obtained by the present invention in the chemicals listed below for 7 days at 23 ° C., changes in the residual mass (%) and appearance of the film were observed. Concentrated hydrochloric acid, 64% sulfuric acid, and glacial acetic acid were tested.

(8) Hydrolysis resistance A hot press film is prepared from the injection molding material of the present invention, and the hot press film is placed in an autoclave, and water (pH = 7), 0.5 mol / l sulfuric acid (pH = 1) or In a 1 mol / l sodium hydroxide aqueous solution (pH = 14), the residual weight ratio (%) and appearance change after treatment at 121 ° C. for 60 minutes were examined.

(9) Mechanical properties [1] to [4] shown below are obtained by molding the following test pieces by injection molding at a resin temperature of 260 ° C. (resin temperature of 290 ° C. for PA66) and a mold temperature of 80 ° C. This was done. The data measured at 23 ° C. after the molding was shown in the table as dry, the moisture was adjusted at a humidity of 65% RH after molding, and the data measured at 23 ° C. was shown in the table.
[1] Tensile yield strength or tensile strength: Measured according to ASTM D638 using a Type I test piece described in ASTM D638.
[2] Flexural modulus: Measured according to ASTM D790 using a test piece with a test piece size of 3.2 mm × 12.7 mm × 127 mm.
[3] Izod impact strength: Measured at 23 ° C. in accordance with ASTM D256 using a test piece with a test piece size of 3.2 mm × 12.7 mm × 127 mm.
[4] Deflection temperature under load (thermal deformation temperature): Measured at a load of 1.82 MPa in accordance with ASTM D648 using a test piece having a test piece size of 3.2 mm × 12.7 mm × 127 mm.

(10) Water absorption rate The water absorption rate (%) was calculated according to the measurement method of (6) saturated water absorption rate, except that it was placed under conditions of 23 ° C. and humidity 65% RH.

(11) Warpage Warpage was evaluated using a test piece obtained by injection molding the injection molding material of the present invention into a box shape shown in FIG. 1 under the injection molding conditions shown below.
[Injection molding conditions]
・ Injection molding machine: IS-80 manufactured by Toshiba Machine Co., Ltd.
Cylinder set temperature: C ₁ 240 ° C .; C ₂ 270 ° C .; C ₃ 270 ° C .; C ₄ 270 ° C .; Nozzle heater 270 ° C.
Injection pressure: primary pressure 650 kg / cm ²
-Mold temperature: Moving mold 40 ° C; Fixed mold 40 ° C
・ Injection time: 11 seconds ・ Cooling time: 20 seconds [Evaluation of warpage]
The dimensions A and B in FIG. 1 were measured and obtained from the following equation with the dimension B as a reference.
Warpage (warping of inward tilt) (%) = (B length−A length) / B length × 100

[Example 1: Production of PA92-1]
Oxalic acid in a pressure vessel with a volume of 150 liters equipped with a stirrer, thermometer, torque meter, pressure gauge, raw material inlet directly connected with a diaphragm pump, nitrogen gas inlet, pressure relief port, pressure regulator and polymer outlet The operation of charging 28.40 kg (140.4 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 After repeated nitrogen substitution, the system was heated while stirring under a sealing pressure. After adjusting the temperature of dibutyl oxalate to 100 ° C. over about 30 minutes, 18.89 kg (119.3 mol) of 1,9-nonanediamine and 3.34 kg (21.1 mol) of 2-methyl-1,8-octanediamine were obtained. ) (Molar ratio of 1,9-nonanediamine and 2-methyl-1,8-octanediamine is 85:15) into a reaction vessel by 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 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 = 3.20.

[Example 2: Production of PA92-2]
A mixture of 17.62 kg (111.3 mol) of 1,9-nonanediamine and 4.45 kg (28.1 mol) of 2-methyl-1,8-octanediamine (1,9-nonanediamine and 2-methyl-1,8 A polyamide was obtained by reacting in the same manner as in Example 1 except that the octanediamine molar ratio was 80:20). The obtained polyamide was a white tough polymer and had ηr = 3.10.

[Example 3: Production of PA92-3]
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 (1,9-nonanediamine and 2-methyl-1,8 -Polyamide was obtained by reacting in the same manner as in Example 1 except that the octanediamine molar ratio was 50:50). The obtained polymer was a white tough polymer, and ηr = 3.35.

[Example 4: Production of PA92-4]
A mixture of 1,9-nonanediamine 6.67 kg (42.1 mol) and 2-methyl-1,8-octanediamine 15.56 kg (98.3 mol) (1,9-nonanediamine and 2-methyl-1,8 -Polyamide was obtained by reacting in the same manner as in Example 1 except that the octanediamine molar ratio was 30:70). The obtained polyamide was a white tough polymer, and ηr = 3.55.

[Example 5: Production of PA92-5]
A mixture of 1.33 kg (8.4 mol) of 1,9-nonanediamine and 20.88 kg (131.9 mol) of 2-methyl-1,8-octanediamine (1,9-nonanediamine and 2-methyl-1,8 -Polyamide was obtained by carrying out the reaction in the same manner as in Example 1 except that the molar ratio of octanediamine was 6:94). The obtained polymer was a white tough polymer, and ηr = 3.53.

[Example 6: Production of PA92-6]
A mixture of 1.33 kg (8.4 mol) of 1,9-nonanediamine and 20.88 kg (131.9 mol) of 2-methyl-1,8-octanediamine (1,9-nonanediamine and 2-methyl-1,8 -The octanediamine molar ratio was 6:94), and the reaction was carried out in the same manner as in Example 1 except that the internal pressure by extracting butanol was maintained at 0.25 MPa to obtain polyamide. The obtained polymer was a white tough polymer, and ηr = 4.00.

[Comparative Example 1: Production of PA-92-0]
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 Example 1 to obtain a polyamide. The obtained polymer was a yellowish white polymer, and ηr = 2.78.

  Table 1 shows the characteristic data of PA92-1 to PA92-6 prepared in Examples 1 to 6 and PA92-0 prepared in Reference Example 1.

[Comparative Examples 2 and 3]
The characteristic data of commercially available products PA6 (Ube Industries, UBE nylon 1015B) and PA66 (Ube Industries, UBE nylon 2020B) are shown in Table 1 as Comparative Examples 2 and 3, respectively.

  From Table 1, the injection molding material of the present invention has low water absorption compared to materials such as nylon 6 and nylon 66, excellent chemical resistance and hydrolysis resistance, and excellent mechanical properties under wet conditions. , And producing a tough molded body having a wider moldable temperature range and better melt moldability and higher molecular weight than polyamide resin (PA92-0) using 1,9-nonanediamine alone as a diamine component You can see that

[Examples 7 to 12]
1 was produced using PA92-1 to PA92-6 prepared in Examples 1 to 6, and then stored at 23 ° C. and a relative humidity of 65%, and the warpage 10 days after production was measured. . The results are shown in Table 2.

[Example 13]
100 parts by mass of PA92-1 pellets were kneaded in a 44 mmφ vented twin screw extruder set at a barrel temperature of 285 ° C. When this polyamide resin is kneaded, a glass fiber (fiber diameter 11 μm, fiber cut length 3 mm) is supplied from the middle of the extruder to 100 parts by mass of the polyamide resin so as to be 43 parts by mass. A pellet was prepared. Next, the injection molded body of FIG. 1 was manufactured using the obtained pellets, and then stored at 23 ° C. and a relative humidity of 65%, and the warpage 10 days after the manufacturing was measured. The results are shown in Table 2.
Note that it is generally known in the art that an injection-molded body to which glass fiber is added has a large warp during molding and low dimensional stability.

[Comparative Example 4]
Except that the polyamide resin was replaced with PA6, the injection-molded article of FIG. 1 was produced according to the procedure of Example 7, and then stored at 23 ° C. and a relative humidity of 65%, and the warpage 10 days after production was measured. The results are shown in Table 2.
[Comparative Example 5]
Except that the polyamide resin was replaced with PA6, the injection-molded article of FIG. 1 was produced according to the procedure of Example 13, and then stored at 23 ° C. and a relative humidity of 65%, and the warpage 10 days after production was measured. The results are shown in Table 2.

Example 14
An intake manifold and a fuel injection were manufactured by injection molding using the injection molding materials of Examples 1 to 6 and Comparative Examples 2 and 3. The injection molding materials of Examples 1 to 6 had the same or better moldability as PA6 and PA66.

  The injection molding material of the present invention is an injection molding material with less warpage, superior dimensional stability, excellent chemical resistance and hydrolysis resistance as compared with injection molding materials such as nylon 6, and as a diamine component. Compared to materials using 1,9-nonanediamine alone, it has a wider moldable temperature range and excellent melt moldability, and can produce a tough molded body that can be made high in molecular weight and has little warpage and excellent dimensional stability. Molded bodies that are required to be manufactured, for example, molded parts suitable for the manufacture of parts having complicated shapes, such as oil tanks for two- and four-wheeled vehicles, intake system parts, integrated parts thereof, electrical component cases, and other containers. Therefore, it is industrially useful.

FIG. 1 is a view showing an injection molded body for measuring warpage.

Claims (5)

  The dicarboxylic acid component consists of oxalic acid, the diamine component consists of 1,9-nonanediamine and 2-methyl-1,8-octanediamine, and the moles of 1,9-nonanediamine and 2-methyl-1,8-octanediamine An injection molding material comprising a polyamide resin having a ratio of 1:99 to 99: 1.   The relative viscosity (ηr) of the polyamide resin measured at 25 ° C. using a polyamide resin solution having a concentration of 1.0 g / dl using 96% sulfuric acid as a solvent is 1.8 to 6.0. 2. The injection molding material according to 1.   1% weight loss temperature in thermogravimetric analysis of the polyamide resin measured at a heating rate of 10 ° C./min in a nitrogen atmosphere, and differential scanning calorimetry measured at a heating rate of 10 ° C./min in a nitrogen atmosphere. The injection molding material according to claim 1 or 2, wherein the temperature difference from the melting point measured by (1) is 50 ° C or more.   The injection molding material according to any one of claims 1 to 3, wherein a molar ratio of 1,9-nonanediamine to 2-methyl-1,8-octanediamine is 5:95 to 95: 5.   An injection molded body produced from the injection molding material according to any one of claims 1 to 4.

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