JP3466330B2 - Polyamide and polyamide composition - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a specific semi-aromatic polyamide and a polyamide composition obtained by blending the polyamide with a filler. The polyamide and the polyamide composition of the present invention have extremely excellent moldability and are excellent in surface beauty, dimensional stability, low water absorption, chemical resistance, heat yellowing resistance, and the like, industrial materials, and industrial materials. It can be suitably used as a molding material for materials and household products.

[0002]

2. Description of the Related Art Conventionally, polyamide resins represented by nylon 6 and nylon 66 have been widely used as fibers for clothing, industrial materials or general-purpose engineering plastics because of their excellent properties and ease of melt molding. However, on the other hand, problems such as insufficient heat resistance and poor dimensional stability due to water absorption have been pointed out. Especially in the fields of electricity and electronics, engine room parts of automobiles,
Conventional polyamides are difficult to use, and there is an increasing demand for polyamides that are more excellent in heat resistance, dimensional stability, mechanical properties, and physicochemical properties.

To meet such requirements, adipic acid and 1,
Totally aliphatic polyamide consisting of 4-butanediamine, semi-aromatic polyamide containing terephthalic acid and 1,6-hexanediamine as main components, and terephthalic acid and branched chain aliphatic diamine 2,2,4- (2,4) Various semi-aromatic polyamides composed of 1,4-) trimethylhexanediamine and semi-aromatic polyamides containing isophthalic acid and 1,6-hexanediamine as main components have been proposed and some of them have been put into practical use.

Japanese Patent Publication No. 49-36959, Japanese Patent Laid-Open No. Sho 6
2-209135 and the like describe a polyamide comprising isophthalic acid and terephthalic acid, 1,6-hexanediamine and a diamine having an alicyclic skeleton. Further, in JP-A-59-155427 and US Pat. No. 4,617,342, terephthalic acid and 1,6-hexanediamine which is a linear aliphatic diamine and 2,2,4 which is a branched aliphatic diamine are disclosed. -(2,4
4-) Polyamides consisting of trimethylhexanediamine are described. However, in these prior art documents, specific examples of polyamides in which 1,9-nonanediamine, which is a straight-chain aliphatic diamine, and 2-methyl-1,8-octanediamine, which is a branched-chain aliphatic diamine, are used in a specific ratio are described. There is no disclosure.

[0005]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention Adipic acid and 1,4-
Polyamide composed of butanediamine (hereinafter abbreviated as PA4-6) and polyamide composed of terephthalic acid and 1,6-hexanediamine (hereinafter abbreviated as PA6-T) are polymers having relatively high crystallinity. In addition, the dimensional change during molding was large, and it could not be used in applications where transparency is required. On the other hand, terephthalic acid and 2,2,4- (2,4,4-) which are branched chain aliphatic diamines
Semi-aromatic polyamide consisting of trimethylhexanediamine and semi-aromatic polyamide consisting mainly of isophthalic acid and 1,6-hexanediamine have good transparency, but yellowing due to use at high temperature and dimensional change due to moisture absorption. , Chemical resistance, etc. are still regarded as problems.

According to the research conducted by the present inventors, isophthalic acid and terephthalic acid, which are obtained by additionally testing the methods described in JP-B-49-36959 and JP-A-62-209135, and 1 Polyamides composed of 6,6-hexanediamine and diamines having an alicyclic skeleton have problems that they have high melt viscosity, insufficient moldability, and insufficient mechanical properties such as impact resistance. Further, JP-A-59-155427 and US Pat. No. 4,617,734.
PA6-, which is obtained by additionally testing the method described in No. 2 specification.
2,2,4 which is a branched chain aliphatic diamine in T polyamide
A polyamide obtained by copolymerizing-(2,4,4-) trimethylhexamethylenediamine has a problem that the molded article is inferior in chemical resistance, dimensional stability when absorbing water, and the like.

The object of the present invention is to improve molding processability as compared with conventional semi-aromatic polyamides, and to improve the surface beauty, dimensional stability, low water absorption, chemical resistance,
It is an object of the present invention to provide a polyamide and a polyamide composition which are excellent in heat yellowing resistance and the like.

[0008]

Means for Solving the Problems As a result of intensive studies for solving the above problems, the present inventors have found that 1,9-nonanediamine unit and 2-methyl-diamine unit as diamine units.
A semi-aromatic polyamide containing 1,8-octanediamine units in a specific ratio is excellent in moldability, low water absorption, chemical resistance and the like, and further, a specific amount of a filler is added to the polyamide. The present invention has been completed by discovering that a polyamide composition having excellent moldability, low water absorption, chemical resistance, and high mechanical strength can be obtained by blending.

That is, according to the present invention, 60 to 100 mol% of dicarboxylic acid units are terephthalic acid units, and 60 to 100 mol% of diamine units are 1,9-nonanediamine units and 2-methyl-1,8-octane. It is composed of diamine units, and the molar ratio of 1,9-nonanediamine units to 2-methyl-1,8-octanediamine units is 40:
60-59: 41 mol% polyamide having an intrinsic viscosity [η] measured in concentrated sulfuric acid at 30 ° C. of 0.4-3.
The polyamide is 0 dl / g. Further, the present invention is based on 100 parts by weight of the above polyamide and 1 to 20 fillers.
A polyamide composition containing 0 part by weight.

The present invention will be described in detail below. The polyamide of the present invention consists essentially of dicarboxylic acid units and diamine units. As the dicarboxylic acid unit, it is necessary to contain a terephthalic acid unit in an amount of 60 mol% or more, preferably 75 mol% or more.
It is more preferable that the content is at least mol%. When the content of the terephthalic acid unit is less than 60 mol%, various properties such as heat resistance and chemical resistance of the obtained polyamide are deteriorated, which is not preferable.

Examples of the dicarboxylic acid unit other than the terephthalic acid unit include malonic acid, dimethylmalonic acid, succinic acid, 3,3-diethylsuccinic acid, glutaric acid and 2,2-
Aliphatic dicarboxylic acids such as dimethylglutaric acid, adipic acid, 2-methyladipic acid, trimethyladipic acid, pimelic acid, azelaic acid, sebacic acid, suberic acid; 1,3-cyclopentanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid Alicyclic dicarboxylic acids such as acids;
Isophthalic acid, 2,6-naphthalenedicarboxylic acid, 2,
7-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,4-phenylenedioxydiacetic acid, 1,3
-Phenylenedioxydiacetic acid, diphenic acid, 4,4'-
Examples thereof include units derived from aromatic dicarboxylic acids such as oxydibenzoic acid, diphenylmethane-4,4'-dicarboxylic acid, diphenylsulfone-4,4'-dicarboxylic acid and 4,4'-biphenyldicarboxylic acid, One or more of these may be included. From the viewpoint of heat resistance and the like, it is preferable to include an aromatic dicarboxylic acid unit among the above dicarboxylic acid units. Further, a unit derived from a polyvalent carboxylic acid having three or more functional groups such as trimellitic acid, trimesic acid, and pyromellitic acid can be included within the range where melt molding is possible.

As the diamine unit, it is necessary to contain 60 mol% or more of 1,9-nonanediamine unit and 2-methyl-1,8-octanediamine unit, and 75 mol% or more. Is preferred, 90
It is more preferable that the content is at least mol%. When the content of the 1,9-nonanediamine unit and the 2-methyl-1,8-octanediamine unit is less than 60 mol%, the obtained polyamide has various physical properties such as moldability, low water absorption and chemical resistance. Is decreased, which is not preferable. In addition, 1,
The molar ratio of 9-nonanediamine unit to 2-methyl-1,8-octanediamine unit is 40:60 to 59:41, and preferably 45:55 to 55:45. As the diamine unit, 1,9-nonanediamine unit and 2-
By containing the methyl-1,8-octanediamine unit in the above proportion, a polyamide having not only excellent moldability but also excellent chemical resistance, low water absorption, mechanical properties and the like can be obtained.

As diamine units other than the 1,9-nonanediamine unit and the 2-methyl-1,8-octanediamine unit, ethylenediamine, propylenediamine, 1,4-butanediamine, 1,6-hexanediamine, 1 , 8-octanediamine, 1,10-decanediamine, 1,12-dodecanediamine, 2-methyl-1,
5-pentanediamine, 3-methyl-1,5-pentanediamine, 2,2,4-trimethyl-1,6-hexanediamine, 2,4,4-trimethyl-1,6-hexanediamine, 5-methyl- 1,9 aliphatic diamines such as nonanediamine; cyclohexane diamine, methylcyclohexane diamine, isophorone diamine, cycloaliphatic diamines, such as norbornane dimethylamine; p-phenylenediamine, m- phenylenediamine, xylylenediamine, 4, 4'- Diaminodiphenylmethane, 4,4 '
Examples thereof include units derived from aromatic diamines such as -diaminodiphenyl sulfone and 4,4'-diaminodiphenyl ether, and one or more of these can be included.

In the polyamide of the present invention, 10% or more of the terminal groups of its molecular chain are preferably capped with an end cap, and more preferably 40% or more of the terminal groups are capped. More preferably, 60% or more of the terminal groups are sealed. By sealing the end group of the polyamide, a polyamide having more excellent moldability and heat yellowing resistance can be obtained.

In order to obtain the terminal blocking ratio, the number of carboxyl group terminals, amino group terminals and terminals blocked by the terminal blocking agent present in the polyamide are respectively measured, and the following formula (1) is used. The terminal sealing rate can be obtained. The number of each terminal group is preferably determined by ¹ H-NMR from the integrated value of the characteristic signal corresponding to each terminal group in terms of accuracy and simplicity. When the characteristic signal of the terminal blocked by the terminal blocking agent cannot be identified, the intrinsic viscosity [η] of the polyamide is measured, and Mn = 21900 [η] -7900 (Mn represents a number average molecular weight) molecular chain The total number of end groups of the molecular chain is calculated using the relationship of the total number of end groups (eq / g) = 2 / Mn. further,
The number of carboxyl group terminals of the polyamide by titration (eq
/ G) [0.1% benzyl alcohol solution of polyamide
Titration with N sodium hydroxide] and the number of amino group terminals (eq / g) [0.1% polyamide solution in phenol]
Titration with N hydrochloric acid] can be measured to determine the end-capping rate by the following formula (1).

End capping rate (%) = [(A−B) ÷ A] × 100 (1) [In the formula, A is the total number of end groups of the molecular chain (this is usually 2 of the number of polyamide molecules). And B represents the total number of carboxyl group terminals and amino group terminals.)

The terminal blocking agent is not particularly limited as long as it is a monofunctional compound having reactivity with an amino group or a carboxyl group at the polyamide terminal, but from the viewpoint of reactivity and stability of the terminal block. , Monocarboxylic acid or monoamine is preferable, and monocarboxylic acid is more preferable from the viewpoint of easy handling. In addition, acid anhydrides such as phthalic anhydride, monoisocyanates, monoacid halides, monoesters and monoalcohols can be used.

The monocarboxylic acid used as the terminal blocking agent is not particularly limited as long as it has reactivity with an amino group, and examples thereof include acetic acid, propionic acid, butyric acid, valeric acid and caproic acid. Aliphatic monocarboxylic acids such as caprylic acid, lauric acid, tridecyl acid, myristic acid, palmitic acid, stearic acid, pivalic acid, isobutyric acid; alicyclic monocarboxylic acids such as cyclohexanecarboxylic acid; benzoic acid, toluic acid, α -Aromatic monocarboxylic acids such as naphthalenecarboxylic acid, β-naphthalenecarboxylic acid, methylnaphthalenecarboxylic acid and phenylacetic acid,
Alternatively, mention may be made of any mixture thereof.
Among these, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, lauric acid, tridecylic acid, myristic acid, palmitic acid, stearic acid from the viewpoints of reactivity, stability of the capped end, price, etc. Benzoic acid is particularly preferred.

When the end groups of the polyamide are sealed with a monocarboxylic acid, the number of moles of the diamine component to the dicarboxylic acid component used in the production of the polyamide is slightly increased so that both ends of the polyamide are amino groups. ,
It is advisable to add monocarboxylic acids as endcapping agents.

The amino group terminal of the polyamide of the present invention is blocked with these monocarboxylic acids to form a blocked terminal represented by the following general formula (I).

[0021]

[Chemical 1] (In the formula, R is a residue obtained by removing a carboxyl group from the above monocarboxylic acid, and is preferably an alkyl group, a cycloalkyl group, an aryl group, or an aralkyl group.)

The monoamine used as the terminal blocking agent is not particularly limited as long as it has reactivity with a carboxyl group, and examples thereof include methylamine, ethylamine, propylamine, butylamine, hexylamine and octylamine. , Aliphatic monoamines such as decylamine, stearylamine, dimethylamine, diethylamine, dipropylamine, dibutylamine; cycloaliphatic monoamines such as cyclohexylamine and dicyclohexylamine; aniline, toluidine, diphenylamine,
Mention may be made of aromatic monoamines such as naphthylamine or any mixtures thereof. Of these, butylamine, hexylamine, octylamine, decylamine, stearylamine, cyclohexylamine, and aniline are particularly preferable from the viewpoints of reactivity, boiling point, stability of capped terminal, price, and the like.

When the end groups of the polyamide are sealed with monoamine, the number of moles of the diamine component to the dicarboxylic acid component used in the production of the polyamide is slightly reduced so that both ends of the polyamide are carboxyl groups. Is preferably added as an end-capping agent.

The carboxyl terminal of the polyamide of the present invention is blocked with these monoamines to form a blocked terminal represented by the following general formula (II).

[0025]

[Chemical 2] (In the formula, R ¹ is a residue obtained by removing an amino group from the above monoamine, and is preferably an alkyl group, a cycloalkyl group, an aryl group or an aralkyl group. R ² is a hydrogen atom or an amino group from the above monoamine. Is a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or an aralkyl group.)

The amount of the end-capping agent used in the production of the polyamide depends on the reactivity of the end-capping agent used, the boiling point,
Although it varies depending on the reaction apparatus, reaction conditions, etc., it is usually 0.1 to 15 relative to the total number of moles of dicarboxylic acid and diamine.
It is preferably used in the range of mol%.

The polyamide of the present invention can be produced by a method such as a melt polymerization method, a solution polymerization method, or a polymerization method using a reactive extruder, which is conventionally known as a method for producing a polyamide. . According to the research conducted by the present inventors, a catalyst and, if necessary, an end-capping agent were first added all at once to a diamine and a dicarboxylic acid to prepare a nylon salt, which was once concentrated at a temperature of 280 ° C. or lower. The intrinsic viscosity [η] at 30 ° C in sulfuric acid is 0.10 to 0.
The polyamide of the present invention can be easily obtained by using a prepolymer of 60 dl / g and further subjecting it to solid phase polymerization or polymerization using a melt extruder. The intrinsic viscosity [η] of the prepolymer is 0.10 to 0.60 dl
Within the range of / g, there is little deviation in the molar balance between the carboxyl group and the amino group and the decrease in the polymerization rate in the post-polymerization stage, and a polyamide having a small molecular weight distribution and excellent performance and moldability can be obtained. . When the final step of the polymerization is carried out by solid phase polymerization, it is preferably carried out under reduced pressure or under the flow of an inert gas, and if the polymerization temperature is in the range of 180 to 280 ° C., the polymerization rate is high and the productivity is excellent. It is preferable because coloring and gelation can be effectively suppressed. When the final stage of the polymerization is carried out by a melt extruder, it is preferable that the polymerization temperature is 370 ° C. or less, because the polyamide is hardly decomposed and the polyamide can be obtained without deterioration.

As catalysts that can be used in the production of polyamides, phosphoric acid, phosphorous acid, hypophosphorous acid, or their ammonium salts, their metal salts (potassium, sodium, magnesium, vanadium, calcium, Metal salts of zinc, cobalt, manganese, tin, tungsten, germanium, titanium, antimony, etc., and their esters (ethyl ester, isopropyl ester, butyl ester, hexyl ester, isodecyl ester, octadecyl ester, decyl ester, stearyl ester) , Phenyl ester) and the like. In addition, if necessary, stabilizers such as copper compounds, colorants, ultraviolet absorbers, light stabilizers, antioxidants such as hindered phenols, thios, phosphorus, amines, antistatic agents, brominated Polymer, antimony oxide, flame retardant such as metal hydroxide, crystal nucleating agent, plasticizer, release agent,
Other additives such as lubricants can be added during or after the polycondensation reaction.

The polyamide of the present invention has an intrinsic viscosity [η] measured in concentrated sulfuric acid at 30 ° C. of 0.4 to 3.0 dl / g and 0.6 to 2.0 dl / g. Those of 0.8 to 1.6 dl / g are more preferable. When the intrinsic viscosity [η] of the polyamide is within the above range, not only excellent moldability but also excellent mechanical properties and heat resistance can be obtained.

In the polyamide of the present invention, the intrinsic viscosity [η]
Is in the range of 0.4 to 3.0 dl / g, the intrinsic viscosity [η]
And the melt viscosity (MV) measured at a shear rate of 1000 s ⁻¹ , the relationship represented by the following formula (2) is established. logMV = 1.9 [η] + A (2) (where A is a number that changes with temperature)

In the case of the preferred polyamides according to the invention, 34
A value at 0 ° C is 0.5 to 0.9, and A value at 330 ° C
The difference between the value and the A value at 350 ° C. is 0.1 to 0.6.
On the other hand, in the case of the conventional PA6-T type polyamide, the coefficient of intrinsic viscosity [η] is almost the same as that of the polyamide of the present invention, but the A value at 340 ° C is 1.3 to 1.7, and 330
The difference between the A value at 0 ° C and the A value at 350 ° C is 0.7 to 1.1.
Is. Thus, the preferable molding temperature is 330 to
At 350 ° C., the polyamide of the present invention is
Compared with -T polyamide, the melt viscosity is small even with the same intrinsic viscosity [η], and the change in melt viscosity with the change in molding temperature is also small. Further, the polyamide of the present invention also has a characteristic that the change in melt viscosity during the residence time during molding is small, and the moldability is significantly improved as compared with the conventional PA6-T based polyamide. There is.

The polyamide of the present invention includes polyamide 10
The filler can be blended in an amount of 1 to 200 parts by weight with respect to 0 parts by weight. By blending the filler in such a ratio, a polyamide composition having improved properties such as mechanical strength and heat distortion temperature can be obtained. The blending ratio of the filler is
The amount is preferably 1 to 150 parts by weight, more preferably 2 to 100 parts by weight, based on 100 parts by weight of the polyamide.

As the filler, conventionally known fillers having various forms such as powder, fiber and cloth can be used.

As the powdery filler, silica, silica alumina, alumina, titanium oxide, zinc oxide, boron nitride, talc, mica, potassium titanate, calcium silicate, magnesium sulfate, aluminum borate, asbestos, glass beads, Examples thereof include carbon black, graphite, molybdenum disulfide, polytetrafluoroethylene and the like. As such a powdery filler, it is usually preferable to use one having an average particle size of 0.1 μm to 200 μm, and more preferably one having an average particle size of 1 μm to 100 μm. Use of these fillers improves the dimensional stability, mechanical properties, heat resistance properties, physicochemical properties, sliding properties and the like of molded articles obtained from the polyamide composition.

As the fibrous filler, polyparaphenylene terephthalamide fiber, polymetaphenylene terephthalamide fiber, polyparaphenylene isophthalamide fiber, polymetaphenylene isophthalamide fiber, condensate of diaminodiphenyl ether and terephthalic acid or isophthalic acid. Examples thereof include wholly aromatic polyamide fibers such as fibers obtained from the above, organic fibrous fillers such as wholly aromatic liquid crystal polyester fibers; and inorganic fibrous fillers such as glass fibers, carbon fibers or boron fibers. The use of such a fibrous filler not only improves the sliding characteristics of the molded article obtained from the polyamide composition, but also
It is preferable because mechanical properties, heat resistance properties, physicochemical properties, etc. are improved. As such a fibrous filler, usually,
It is preferable to use one having an average length of 0.05 to 50 mm. Further, it is more preferable to use one having an average length in the range of 1 to 10 mm from the viewpoint that the moldability is good and the sliding properties, heat resistance and mechanical properties of the obtained molded product are further improved. These fibrous fillers may be secondarily processed into a cloth shape or the like.

These fillers can be used either individually or in combination of two or more. In particular, it is preferable to use a combination of the above fibrous filler and powdered filler because it is possible to obtain a composition having more excellent moldability, surface beauty, mechanical properties, and heat resistance. . Further, as these fillers, those surface-treated with a silane coupling agent or a titanium coupling agent may be used. It is preferable to use a filler whose surface is treated with these coupling agents, because the resulting molded article has excellent mechanical properties. Among the silane coupling agents, it is more preferable to use an aminosilane coupling agent because the resulting molded product has particularly excellent mechanical properties.

The method of blending the above-mentioned filler with the polyamide is not particularly limited, but examples thereof include a method of adding during the polycondensation reaction of the polyamide, a method of dry blending, and a method of melt kneading using an extruder. And so on.

Using the polyamide or polyamide composition prepared as described above, a molded article having a desired shape can be formed by a usual melt molding method such as compression molding method, injection molding method, extrusion molding method or blow molding method. Can be manufactured.

For example, the polyamide or the polyamide composition of the present invention is melted in a cylinder of an injection molding machine whose cylinder temperature is adjusted to 260 to 350 ° C., and introduced (injected) into a mold having a predetermined shape. By doing so, a molded product can be manufactured. Also, a film can be produced by melting the resin in the extruder adjusted to the cylinder temperature and extruding the resin from the T die.
Further, a molded product such as a film or a bottle can be obtained by inflation molding or blow molding.

The molded product as described above can be used in a state where the surface thereof is further coated with a paint, a metal layer, another kind of polymer or the like.

The polyamide or polyamide composition of the present invention is used for automobiles such as electric tools, general industrial parts, mechanical parts such as gears and cams, automobile interior and exterior parts, automobile electrical parts, parts in the engine room of automobiles, etc. It can be usefully used as a molding material such as related components, printed wiring boards, electronic components such as housings of electronic components, optical lenses, disc substrates, components requiring transparency such as containers, films, sheets and the like.

[0042]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited thereto. In the following examples, the terminal sealing rate of polyamide, the intrinsic viscosity, the melting point, the glass transition point, the melt viscosity; the water absorption rate of the molded product, the heat yellowing, the alcohol resistance, and the appearance of the molded product are measured by the following methods or evaluated.

End capping ratio : ¹ H-NMR (500 MH
z, measured in deuterated trifluoroacetic acid at 50 ° C.) to measure the number of carboxyl group end, amino group end and capping end respectively from the integrated value of the characteristic signal for each end group, The terminal sealing rate was calculated from (1). The chemical shift values of typical signals used for measurement are shown below.

[0044]

[Table 1]

Intrinsic viscosity [η]: in concentrated sulfuric acid at 30 ° C.
The intrinsic viscosity (ηinh) of the samples having the concentrations of 0.05, 0.1, 0.2 and 0.4 g / dl was measured, and the value obtained by extrapolating this to the concentration of 0 was defined as the intrinsic viscosity [η]. ηinh = [ln (t ₁ / t ₀ )] / c [wherein, ηinh is an intrinsic viscosity (dl / g), t ₀ is a solvent flowing time (seconds), t ₁ is a sample solution flowing time (seconds) , C
Represents the concentration (g / dl) of the sample in the solution. ]

Melting point, glass transition point : Using a differential scanning calorimeter (“DSC30” manufactured by METTLER CORPORATION), the sample was heated to 100 ° C.
The temperature of the second-order transition point that appears when the temperature is raised at a rate of 10 ° C./min to completely melt it, then cooled to 50 ° C. at a rate of 10 ° C./min, and again raised at a rate of 10 ° C./min. The temperature at the position of the glass transition point and the endothermic peak was taken as the melting point.

Melt viscosity : KAYNESS "capillary rheometer, GALAXYV MODEL 805
2 "(die diameter 1 mm, L / D = 10)
Melt viscosity at 0 ° C. at a shear rate of 1000 s ⁻¹ (p
oise) was measured and used as an index of moldability.

Water absorption rate : An injection-molded article of 80 × 80 × 3 mm was immersed in water at 23 ° C. for 24 hours, and the water absorption rate (%) was determined from the weight change of the molded article before and after the immersion.

Heat Yellowing : 40 × 100 × 1 mm injection-molded article was heated in a gear oven at 200 ° C. for 2 hours,
Cool to room temperature in a vacuum desiccator for 1 hour.
The difference (Δb) in yellowness (b value) before and after heat treatment was used as an index of heat yellowing. The b value is based on the color computer (SM color tester "SM3
Type ").

Alcohol resistance : A JIS No. 2 dumbbell type injection molded article was immersed in methanol at 23 ° C. for 7 days.
The tensile strength of the molded product before and after the immersion was measured to determine the retention rate (%) of the tensile strength. Furthermore, the appearance was visually observed. The tensile strength was measured according to JIS K7113.

Appearance of molded product : Cylinder temperature 3 using an injection molding machine "FS80S12ASE" manufactured by Nissei Plastic Industry Co., Ltd.
40 × 100 × 1 under conditions of 10 ° C and mold temperature of 100 ° C
A mm flat plate was molded, and the appearance of the molded product was visually evaluated.

Example 1 3272.9 g (19.7 mol) of terephthalic acid, 1,9
1582.9 g (10.0 mol) of nonanediamine, 2
-Methyl-1,8-octanediamine 1582.9 g
(10.0 mol), benzoic acid 73.27 g (0.60 mol), sodium hypophosphite monohydrate 6.5 g (0.1% by weight relative to the raw material) and distilled water 2.2 liters. It was placed in an autoclave having an internal volume of 20 liters and purged with nitrogen. After stirring at 100 ° C for 30 minutes, the internal temperature was raised to 210 ° C over 2 hours. At this time, the pressure in the autoclave was increased to 22 kg / cm ² . After continuing the reaction for 1 hour as it is, the temperature was raised to 230 ° C., and then the temperature was kept at 230 ° C. for 2 hours, and steam was gradually discharged to a pressure of 22 kg / c.
The reaction was carried out while maintaining m ² . Next, the temperature is raised to 280 ° C. over 45 minutes and the pressure is reduced to the atmospheric pressure. Further, the pressure is lowered to a vacuum state of 1 mmHg over 15 minutes with the temperature kept at 280 ° C. and the reaction is performed for 30 minutes to obtain an intrinsic viscosity [ A polyamide having an η] of 1.35 dl / g and a terminal sealing rate of 89% was obtained. The obtained polyamide was injection molded by using an injection molding machine "FS80S12ASE" manufactured by NISSEI PLASTIC INDUSTRIAL CO., LTD. With the cylinder temperature set to 300 ° C and the mold temperature set to 100 ° C. Table 2 below shows the results of evaluation of the obtained molded products.

Examples 2 to 5, Comparative Examples 1 to 3 Examples except that the dicarboxylic acid component, diamine component and end-capping agent (benzoic acid) shown in Table 2 below were used in the proportions shown in Table 2 A polyamide was obtained in the same manner as in 1. The obtained polyamide was applied to the injection molding machine "F
S80S12ASE "to adjust the cylinder temperature to 28
Injection molding was performed by setting the mold temperature to 0 to 310 ° C and the mold temperature to 100 ° C. Table 2 below shows the results of evaluation of the obtained molded products.

[0054]

[Table 2]

Examples 6 and 7 and Comparative Example 4 Example 1 and Example 3 except that the dicarboxylic acid component, diamine component and terminal blocking agent (benzoic acid) shown in Table 3 below were used in the proportions shown in Table 3. A polyamide was obtained in the same manner. Uniaxial extruder "UT-40H" manufactured by Plastic Engineering Laboratory
And the cylinder temperature was set to 280 to 310 ° C., and the obtained polyamide and the fillers shown in Table 3 below were extruded in a molten state to obtain a polyamide composition. The glass fiber has a fiber diameter of 9.5μ.
m, average length 3 mm, made of Nippon Glass Fiber "RES03-TP
57 "was used. Talc has an average particle size of 5 to 6 μ.
“PKP-80” manufactured by Kato Tsuchiya Kaolin was used. The obtained polyamide composition was injection-molded using an injection molding machine "FS80S12ASE" manufactured by NISSEI PLASTIC INDUSTRIAL CO., LTD. With a cylinder temperature of 280 to 310 ° C and a mold temperature of 100 ° C. Table 3 below shows the results of evaluation of the obtained molded products.

[0056]

[Table 3]

[0057]

EFFECT OF THE INVENTION The polyamide and the polyamide composition of the present invention have extremely excellent moldability and are excellent in surface beauty, dimensional stability, low water absorption, chemical resistance, heat yellowing resistance and the like. It can be suitably used as a molding material for industrial materials, industrial materials, household products and the like.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-7-53715 (JP, A) Patent 3242781 (JP, B2) (58) Fields investigated (Int.Cl. ⁷ , DB name) C08G 69/00 -69/50 CA (STN) REGISTRY (STN)

Claims (3)

(57) [Claims] 1. 60 to 100 mol% of dicarboxylic acid units
Is a terephthalic acid unit, and is a diamine unit of 60 to 1
00 mol% consists of 1,9-nonanediamine units and 2-methyl-1,8-octanediamine units, and the molar ratio of 1,9-nonanediamine units to 2-methyl-1,8-octanediamine units is 40: 60 ~ 59: 41
A polyamide having a mol% and an intrinsic viscosity [η] measured in concentrated sulfuric acid at 30 ° C. of 0.4 to 3.0 dl / g. 2. The polyamide according to claim 1, wherein 10% or more of the terminal groups are capped. 3. The polyamide 10 according to claim 1 or 2.
A polyamide composition comprising 1 to 200 parts by weight of a filler in 0 parts by weight.