JP2000204239A - Polyamide composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a polyamide composition which can give a molding having excellent heat resistance, water absorption characteristics, and chemical resistance by blending two polyamides in a specified ratio. SOLUTION: This composition is obtained by blending polyamide A with polyamide B in a weight ratio satisfying the relationships: B/(A+B)×100>=10. Polyamide A comprises units selected from the group consisting of hexamethylene terephthalamide units (a), hexamethylene isophthalamide units (b), hexamethylene adipamide units (c), and capramide units (d) on conditions that any of the following relationships is satisfied: a/b=55/45 to 80/20, a/c=20/80 to 80/20, and a/d=55/45 to 90/10. Polyamide B comprises dicarboxylic acid units containing 60-100 mol% terephthalic acid units and diamine units containing 60-100 mol% 1,9-nonanediamine units and/or 2-methyl-1,8- octanediamine units in a molar ratio of the former units to the latter units of 100/0 to 20/80.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a polyamide composition and a molded article comprising the same. The polyamide composition provided by the present invention has excellent heat resistance, water absorption properties and chemical resistance, and various industrial materials, industrial materials,
It can be suitably used as household goods, especially electric / electronic parts and automobile parts.

[0002]

2. Description of the Related Art Aliphatic polyamides represented by nylon 6, nylon 66 and the like have been widely used as clothing, industrial material fibers, engineering plastics and the like because of their excellent properties and ease of melt molding. I have. However, on the other hand, it has been pointed out that these general-purpose polyamides have problems in points such as insufficient heat resistance and poor dimensional stability due to water absorption. In particular, in recent years, polyamides used in fields such as electric / electronic parts, automobile parts, and engineering plastics have been required to have high performance. For example, in electric / electronic parts, surface mount technology (SMT) has been required. With the development, high heat resistance such as reflow soldering heat resistance has been required, and polyamides having even higher heat resistance than before have been demanded for automobile parts such as engine room parts. Moreover, in conjunction with the expanding use of polyamides, not only in electric / electronic parts and automobile parts, but also in other fields of application, polyamides with even better physical properties and functions are required. At the same time, there is a demand for the development of polyamides having excellent dimensional stability and chemical resistance.

[0003] In response to the above requirements, polyamides comprising terephthalic acid and 1,6-hexanediamine (hereinafter referred to as "polyamides")
Various types of semi-aromatic polyamides whose main component is PA6-T) have been proposed. Since PA6-T has a melting point near 370 ° C., which is higher than the decomposition temperature of the polymer, melt polymerization and melt molding are difficult and are not practical. Therefore, by actually copolymerizing a dicarboxylic acid component such as adipic acid and isophthalic acid, or an aliphatic polyamide such as nylon 6 by 30 to 50 mol%,
At present, it is used in a temperature range where the melting point can be reduced to a practically usable temperature range, that is, about 280 to 320 ° C. Copolymerizing such a large amount of the third component, and possibly the fourth component in some cases, is certainly effective in lowering the melting point of the polymer, but on the other hand, it lowers the crystallinity, lowers the ultimate crystallinity, and reduces the heat resistance. As a result, not only performance such as rigidity at high temperature, chemical resistance, dimensional stability, melt stability, etc., but also the extension of molding cycle In some cases, productivity may be reduced.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a liquid crystal display device comprising: a conventional aliphatic polyamide and a semi-aromatic polyamide;
An object of the present invention is to provide a polyamide composition having heat resistance enough to withstand use in a high-temperature atmosphere, low water absorption and sufficient chemical resistance.

[0005]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, 1,6-nonanediamine unit and / or 2-methyldiamine unit were added to PA6-T-based polyamide as a diamine unit. The inventors have found that a composition having excellent heat resistance, water absorption properties and chemical resistance can be obtained by blending a semi-aromatic polyamide having -1,8-octanediamine unit, and completed the present invention.

That is, the present invention provides a hexamethylene terephthalamide unit (a), a hexamethylene isophthalamide unit (b), and a hexamethylene adipamide unit (c).
And a polyamide (A) comprising at least one unit selected from the group consisting of: and a caproamide unit (d), wherein the proportion of each unit satisfies any of the following formulas (1) to (3) by weight: A dicarboxylic acid unit containing 60 to 100 mol% of a terephthalic acid unit and 60 to 100 mol% of a 1,9-nonanediamine unit and / or 2-methyl-1,8-octanediamine unit, and 1,9-
The polyamide (B) is composed of a diamine unit having a molar ratio of nonanediamine unit to 2-methyl-1,8-octanediamine unit of 100: 0 to 20:80, and the weight of the polyamide (A) and the polyamide (B). The present invention relates to a polyamide composition having a ratio satisfying the following formula (4). (A) / (b) = 55 / 45-80 / 20 (1) (a) / (c) = 20 / 80-80 / 20 (2) (a) / (d) = 55 / 45-90 / 10 (3) (B) / [(A) + (B)] × 100 ≧ 10 (4) The present invention also relates to a molded article comprising the above polyamide composition.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Polyamide (A) in the present invention
Is a hexamethylene terephthalamide unit (a), a hexamethylene isophthalamide unit (b), a hexamethylene adipamide unit (c) and a caproamide unit (d)
And at least one unit selected from the group consisting of the above formulas (1) to (4)
Any of (3) is satisfied. (A) /
(B) is preferably in the range of 60/40 to 80/20, and 6
The range of 0/40 to 75/25 is more preferable. (A) /
(C) is preferably in the range of 30/70 to 70/30,
The range of 0/70 to 60/40 is more preferable. Also,
(A) / (d) is preferably in the range of 60/40 to 85/15, more preferably in the range of 60/40 to 80/20.
Polyamide (A) having a ratio of hexamethylene terephthalamide unit (a) to hexamethylene isophthalamide unit (b), hexamethylene adipamide unit (c) and / or caproamide unit (d) within the above range.
Has a melting point in the range of about 270 ° C. to about 340 ° C., has excellent heat resistance, and has good melt stability and moldability. When the ratio of the hexamethylene terephthalamide unit (a) is smaller than the ratio defined by the above formulas (1) to (3), the melting point of the polyamide (A) is low, and the heat resistance is poor. When the ratio of the hexamethylene terephthalamide unit (a) is larger than the ratio defined by the above formulas (1) to (3),
While the melting point of the polyamide (A) is too high and the heat resistance is improved, the molding temperature is high, and thermal decomposition tends to occur at a temperature at which molding is possible.

The degree of polymerization of the polyamide (A) is not particularly limited, but the intrinsic viscosity [η] measured at 30 ° C. in concentrated sulfuric acid.
Is preferably in the range of 0.4 to 3.0 dl / g, and the range is more preferably 0.6 to 2.0 dl / g.
8-1.8 dl / g is more preferred.

The polyamide (A) is composed of each monomer constituting a hexamethylene terephthalamide unit (a), a hexamethylene isophthalamide unit (b), a hexamethylene adipamide unit (c) and / or a caproamide unit (d). Alternatively, it can be produced by any method known as a method for producing a crystalline polyamide by using a salt thereof, but may be produced in one step in a polymerization reaction tank, or in two steps in a polymerization reaction tank. In other words, it is preferable to produce by a method of forming a primary condensate and then increasing the degree of polymerization. From the viewpoint of the thermal stability of the polyamide (A), it is more preferable to employ the two-stage method.

In the polyamide (B) of the present invention, 60 to 100 mol% of dicarboxylic acid units are terephthalic acid units, and the proportion is preferably 75 to 100 mol%.
0-100 mol% is more preferable. When the terephthalic acid unit is less than 60 mol%, the resulting polyamide has reduced heat resistance and chemical resistance.

The dicarboxylic acid units other than the terephthalic acid unit include, for example, malonic acid, dimethylmalonic acid, succinic acid, glutaric acid, adipic acid, 2-methyladipic acid, trimethyladipic acid, pimelic acid, 2,2-dimethyl Aliphatic dicarboxylic acids such as glutaric acid, 3,3-diethylsuccinic acid, azelaic acid, sebacic acid, suberic acid and dimer acid; alicyclics such as 1,3-cyclopentanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid Dicarboxylic acid; isophthalic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1,4-
Naphthalenedicarboxylic acid, 1,4-phenylenedioxydiacetic acid, 1,3-phenylenedioxydiacetic acid, diphenic acid, dibenzoic acid, 4,4′-oxydibenzoic acid, diphenylmethane-4,4′-dicarboxylic acid, Examples include units derived from aromatic dicarboxylic acids such as diphenylsulfone-4,4'-dicarboxylic acid and 4,4'-biphenyldicarboxylic acid, and these may be contained alone or in combination of two or more. Of these, units derived from aromatic dicarboxylic acids are preferred. Further, polyamide (B) is trimellitic acid, as long as melt molding is possible.
It may contain a unit derived from a polycarboxylic acid such as trimesic acid or pyromellitic acid.

In the polyamide (B) of the present invention, 60 to 100 mol% of the diamine units are 1,9-nonanediamine units and / or 2-methyl-1,8-octanediamine units, and the proportion is 75 to 100%. Mol% is preferable, and 90 to 100 mol% is more preferable. 1,9-
The molar ratio of nonanediamine units to 2-methyl-1,8-octanediamine units is from 100: 0 to 20:80,
The ratio is preferably 100: 0 to 60:40,
0: 0 to 80:20 is more preferable. When the composition of the diamine unit is in the above-mentioned situation, the obtained polyamide (B) has excellent heat resistance.

The diamine units other than the 1,9-nonanediamine unit and the 2-methyl-1,8-octanediamine unit include, for example, ethylenediamine, propylenediamine, 1,4-butanediamine, 1,6-hexanediamine, 7,7-heptanediamine, 1,8-octanediamine, 1,10-decanediamine, 1,11-undecanediamine, 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
Aliphatic diamines such as -hexanediamine and 5-methyl-1,9-nonanediamine; cyclohexanediamine;
Methylcyclohexanediamine, isophoronediamine,
Alicyclic diamines such as bis (4-aminocyclohexyl) methane, norbornanedimethylamine and tricyclodecanedimethylamine; p-phenylenediamine, m-phenylenediamine, xylenediamine, 4,4′-diaminodiphenylmethane, 4,4 ′ And units derived from aromatic diamines such as -diaminodiphenylsulfone and 4,4'-diaminodiphenylether. These may be used alone or in combination of two or more.

[0014] The polyamide (B) is sealed with a terminal blocking agent which is a monofunctional compound having a molecular chain terminal group reactive with an amino group or a carboxyl group at the polyamide terminal, such as monocarboxylic acid or monoamine. It may be.
By the end capping, the performance of the polyamide (B) such as melt stability and hot water resistance is further improved.

The monocarboxylic acid which can be used as a terminal blocking agent is not particularly limited as long as it has reactivity with an amino group. For example, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid Aliphatic monocarboxylic acids such as acids, lauric acid, tridecylic acid, myristic acid, palmitic acid, stearic acid, pivalic acid, and isobutylic acid; alicyclic monocarboxylic acids such as cyclohexanecarboxylic acid; benzoic acid, toluic acid, α- Naphthalene carboxylic acid, β-naphthalene carboxylic acid, methyl naphthalene carboxylic acid, aromatic monocarboxylic acids such as phenylacetic acid,
Alternatively, an arbitrary mixture thereof can be mentioned.
Among them, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, lauric acid, tridecylic acid, myristic acid, palmitic acid, stearic acid are considered from the viewpoints of reactivity, sealed terminal stability, and price. And benzoic acid are particularly preferred.

The monoamine used as the terminal blocking agent is not particularly limited as long as it has reactivity with a carboxyl group. For example, methylamine, ethylamine, propylamine, butylamine, hexylamine, octylamine Aliphatic monoamines such as decylamine, stearylamine, dimethylamine, diethylamine, dipropylamine and dibutylamine; cycloaliphatic monoamines such as cyclohexylamine and dicyclohexylamine; aniline, toluidine, diphenylamine,
An aromatic monoamine such as naphthylamine, or an arbitrary mixture thereof can be mentioned. Among these, butylamine, hexylamine, octylamine, decylamine, stearylamine, cyclohexylamine, and aniline are particularly preferable in terms of reactivity, high boiling point, stability of the sealed terminal, and price.

The polyamide (B) preferably has an intrinsic viscosity [η] of 0.4 to 3.0 dl / g measured in concentrated sulfuric acid at 30 ° C., and the range is 0.6 to 2.0 dl / g. g
Is more preferable, and 0.8 to 1.8 dl / g is still more preferable. The polyamide (B) has an intrinsic viscosity of 0.4 dl
If it is less than / dl / g, the mechanical properties may be impaired, and if it is more than 3.0 dl / g, the fluidity during molding may decrease, and the moldability may deteriorate, which is not preferred.

The polyamide (B) can be produced by using any known method for producing a crystalline polyamide. For example, it can be produced by a solution polymerization method or an interfacial polymerization method using acid chloride and diamine as raw materials; a melt polymerization method using dicarboxylic acid and diamine as raw materials, a solid phase polymerization method, a melt extruder polymerization method, or the like. is there. In the production of polyamides, phosphoric acid, phosphorous acid, hypophosphorous acid, or salts thereof, and esters thereof, for the purpose of increasing the rate of polycondensation and preventing the polyamide formed during polymerization from deteriorating. It is preferable to add a phosphorus-based catalyst such as a catalyst to the reaction system. Of these, a hypophosphorous acid derivative is preferred from the viewpoint of the quality of the produced polyamide, and particularly, sodium hypophosphite is preferred from the viewpoint of cost and ease of handling. The addition amount of these phosphorus-based catalysts is preferably 0.01 to 5% by weight based on the total weight of dicarboxylic acid and diamine, and 0.05 to 2% by weight.
%, More preferably 0.07 to 1% by weight. The amount of the terminal blocking agent varies depending on the reactivity of the terminal blocking agent used, the boiling point, the reaction apparatus, the reaction conditions, and the like, but is usually 0 to the total number of moles of the dicarboxylic acid and the diamine. It can be used within a range of 0.1 to 15 mol%.

The following is an example of a method for producing the polyamide (B). If necessary, a catalyst and an end capping agent are first added to the diamine and the dicarboxylic acid at once, to produce a nylon salt, and then, once at a temperature of 200 to 250 ° C, the intrinsic viscosity at 30 ° C in concentrated sulfuric acid [η] ] Is 0.10
Polyamide (B) can be easily obtained by using a prepolymer of 0.60 dl / g and further performing solid phase polymerization or performing polymerization using a melt extruder. The intrinsic viscosity [η] of the prepolymer is 0.10 to 0.60 dl
/ G within the range of the carboxyl group and the amino group in the post-polymerization stage, less decrease in the polymerization rate and lowering of the polymerization rate, and furthermore, a polyamide having a small molecular weight distribution and excellent in various performances and moldability can be obtained. . When the final stage of the polymerization is carried out by solid-phase polymerization, it is preferable to carry out under reduced pressure or an inert gas flow, and when the polymerization temperature is in the range of 200 to 280 ° C, the polymerization rate is large 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 lower, since the polyamide is hardly decomposed and a polyamide without deterioration is obtained.

The polyamide composition of the present invention can be obtained by blending the polyamide (A) and the polyamide (B) such that the weight ratio of the two satisfies the above formula (4). The weight ratio of the polyamide (A) to the polyamide (B) preferably satisfies the following expression (5). (B) / [(A) + (B)] × 100 ≧ 20 (5) If the blending ratio of the polyamide (B) defined by the above formula (4) is less than 10% by weight, the polyamide (B) Has high water absorption and has a reduced chemical resistance.

The method of blending the polyamide (A) and the polyamide (B) is not particularly limited, and a method of melt-kneading with a single screw extruder or a twin screw extruder is employed.

The polyamide composition of the present invention may further contain a filler. As the filler, for example,
Glass fibers or beads, talc, kaolin, wollastonite, mica, silica, alumina, diatomaceous earth,
Examples include powdery or plate-like inorganic compounds such as clay, gypsum, red iron, graphite, titanium dioxide, zinc oxide, copper, and stainless steel, and polymer fibers such as liquid crystal fiber and carbon fiber. Of these, glass fibers are preferred, and glass rovings, glass chopped strands, glass threads, and the like prepared from strands of continuous long fibers having a diameter of about 3 to 20 μm are particularly preferred. The compounding amount of the filler is preferably in the range of 0.1 to 200 parts by weight, more preferably in the range of 0.1 to 150 parts by weight, and still more preferably 10 to 100 parts by weight, based on 100 parts by weight of the polyamide. If the compounding ratio of the filler exceeds 200 parts by weight, the fluidity at the time of melting deteriorates, and not only it becomes difficult to injection-mold a thin-walled molded product, but also the appearance of the molded product is deteriorated.

The method of blending the filler with the polyamide composition of the present invention is not particularly limited, and any known method can be employed. For example, a filler is dry-blended to pellets of polyamide (A) and polyamide (B), and the blend is melt-kneaded by a single screw extruder or a twin screw extruder.

The composition of the present invention may contain, if necessary, a heat stabilizer such as a hindered phenol type, a hydroquinone type, a phosphite type or a substituted product thereof, such as copper iodide, potassium iodide, and sodium hypophosphite. ), Weathering stabilizers (resorcinol-based, salicylate-based, benzotriazole-based, benzophenone-based, hindered amine-based, etc.), plasticizers, release agents and lubricants (montanic acid and its salts, esters, half esters, stearyl alcohol, Stearamide, various bisamides, bisurea, polyethylene wax, etc.), pigments (cadmium sulfide, phthalocyanine, carbon black, etc.), dyes (eg, nigrosine), other polymers (other polyamides, polyesters, polycarbonates, polyphenylene ethers, polyphenylenesul) I de, liquid crystal polymers, polyether sulfone, ABS resin, SAN resin, polystyrene, acrylic resins, polyethylene, polypropylene,
Ethylene / α-olefin copolymer, ionomer resin, styrene-based elastomer called SBS, SEBS, SEPS, etc.).

The polyamide composition of the present invention includes switches, micro slide switches, DIP switches, switch housings, lamp sockets, binding bands, connectors, connector housings, connector shells, IC sockets, coil bobbins, bobbin covers. , Relays, relay boxes, condenser cases, motor internal parts, small motor cases, gears, cams, dancing pulleys, spacers, insulators, fasteners, buckles, wire clips, bicycle wheels, casters, helmets, terminal blocks, power tools Housing, insulation of starter, spoiler, canister, radiator tank, chamber tank, reservoir tank,
Fuse box, air cleaner case, air conditioner fan, terminal housing, wheel cover, intake / exhaust pipe, bearing retainer, cylinder head cover, intake manifold, water pipe impeller, engine roll damper, clutch release, speaker diaphragm, heat-resistant container, microwave oven Parts, rice cooker parts, printer ribbon guide, double-sided adhesive tape between IC chips, double-sided adhesive tape between IC and lead, electrical / electronic related parts, automobile / vehicle related parts, home /
It can be used for office electrical product parts, computer related parts, facsimile / copier related parts, machine related parts, and various other uses.

[0026]

EXAMPLES The present invention will now be described specifically with reference to examples, but the present invention is not limited by these examples. The intrinsic viscosity [η] and melting point (T
m), water absorption, dimensional change, solder resistance and LLC resistance
The methods for measuring and evaluating the water resistance (long life coolant resistance, engine cooling water resistance) are shown below.

Intrinsic viscosity [η]: The polyamide is dissolved in concentrated sulfuric acid and the concentrations are 0.05, 0.1, 0.2 and 0.1.
A sample solution of 4 g / dl was prepared, the intrinsic viscosity at 30 ° C. (η inh) was measured, and the value extrapolated to a concentration of 0 was defined as the intrinsic viscosity [η] (dl / g). ηinh = [ln (t1 / t0)] / c [wherein, ηinh represents the intrinsic viscosity (dl / g), t0 represents the flow time of the solvent (second), and t1 is the flow time of the sample solution (second). And c is the concentration of the sample in the solution (g / dl)
Represents ]

Melting point (Tm): Using a differential scanning calorimeter (“DSC30” manufactured by Mettler), the polyamide was heated at 350 ° C. for 2 minutes in a DSC furnace under a nitrogen stream to completely melt the polyamide. The temperature was lowered to 50 ° C. at a rate of 100 ° C./min, and the position of an endothermic peak appearing when the temperature was raised again at a rate of 10 ° C./min was measured and defined as a melting point (° C.).

Water absorption: An injection molded plate (80 × 80 × 3 mm) molded at a mold temperature of 150 ° C. was immersed in water at 23 ° C. for 24 hours, and the weight before and after immersion was measured to determine the water absorption (%). Was.

Dimensional change rate: An injection molded plate (80 × 80 × 3 mm) molded at a mold temperature of 140 ° C. was heated in a gear oven at 200 ° C. for 2 hours, and the test piece MD direction (flow direction) before and after heating was measured. The dimensional change (%) was measured.

Solder resistance: Injection-molded plate (40 × 100 ×) that has absorbed moisture to a saturated state in an atmosphere of 23 ° C. and 50% RH.
2 mm) was immersed in a solder bath at a predetermined temperature for 10 seconds, and the maximum temperature (° C.) at which no change in appearance was measured.

LLC resistance: A JIS No. 2 dumbbell type injection molded product (2 mm thick) is immersed in a 50% LLC (130% LLC (red): long life coolant, engine coolant) aqueous solution at 130 ° C. for 120 hours. Before and after the treatment, the tensile strength was measured in accordance with JIS K 7113, and the tensile strength retention (%) after the treatment relative to the tensile strength before the treatment was determined.

Reference Example 1 (Production of polyamide-1) Hexamethylene ammonium adipate (66 salt) 9.
00 kg, 6.72 kg of terephthalic acid, 7.02 kg of a 64.5% by weight aqueous solution of hexamethylenediamine, and 6.40 kg of ion-exchanged water were charged into a 0.10 m ³ batch-type pressure polymerization pot (diamine component unit and dicarboxylic acid component). After 1 mol% of terephthalic acid was excessively charged based on the total number of moles in the unit) and the atmosphere was sufficiently replaced with nitrogen, heating was continued. The temperature was raised to 255 ° C. over 3.5 hours with stirring, and the polymerization pressure was adjusted to 40 kg / cm ² -G. For another 30 minutes,
The temperature was maintained at 255-260 ° C. to complete the reaction.
Discharge is 3 liter /
It is supplied at a time rate and the steam pressure is 40 kg / cm ² -G
For 1 hour. The obtained primary condensate has an intrinsic viscosity [η] of 0.3 dl / g and a melting point of 287.
° C. This primary condensate was vacuum-dried at 100 ° C. for 24 hours, and then melted and polymerized at a maximum resin temperature of 325 ° C. with a residence time of 200 seconds and a maximum resin temperature of 325 ° C. in a 30 mmφ vented twin-screw extruder to obtain an intrinsic viscosity [η] 15 dl / g, melting point 298 ° C
To obtain white pellets of polyamide. The discharge of the primary condensate was stable, and the above-mentioned polyamide having a high molecular weight and a high melting point (hereinafter abbreviated as PA6T / 66) could be obtained.

REFERENCE EXAMPLE 2 (Production of polyamide-2) 8.76 kg of terephthalic acid, 8.93 kg of a 64.5% by weight aqueous solution of hexamethylenediamine, 6.00 kg of ε-caprolactam and 6.66 kg of ion-exchanged water were added to 0.1%.
The mixture was charged into a 10 m ³ batch-type pressure polymerization kettle (2 mol% terephthalic acid was excessively charged with respect to the total number of moles of the monomer, dicarboxylic acid component and diamine component), and after sufficient nitrogen substitution, heating was continued. . The temperature was raised to 270 ° C. over 5 hours with stirring, and the polymerization pressure was adjusted to 40 kg / cm ² -G. The reaction was maintained at a temperature of 270-275 ° C. for a further 30 minutes to complete the reaction. Discharge was performed over 1 hour while supplying ion-exchanged water at a rate of 2 liters / hour by a constant volume pump and maintaining the steam pressure at 45 kg / cm ² -G. The intrinsic viscosity [η] of the obtained primary condensate is 0.24
dl / g, melting point was 300 ° C. This primary condensate was melt-highened in the same manner as in Reference Example 1 to obtain a polyamide white pellet having an intrinsic viscosity [η] of 1.10 dl / g and a melting point of 310 ° C. The discharge of the primary condensate is stable, and the high molecular weight and high melting point polyamide (hereinafter referred to as PA
6T / 6).

Reference Example 3 (Production of polyamide-3) Salt 1 composed of terephthalic acid and hexamethylenediamine
4.0 kg, 6.0 kg of a salt composed of isophthalic acid and hexamethylenediamine, 20 g of sodium hypophosphite, and 9.0 kg of ion-exchanged water are charged into a 0.10 m ³ batch-type pressure polymerization polymerization vessel (monomer and dicarboxylic acid components). ,
After 2 mol% of terephthalic acid was excessively charged relative to the total number of moles of the diamine component), and the atmosphere was sufficiently replaced with nitrogen, heating was continued. The temperature was raised to 290 ° C. over 5 hours with stirring, and the polymerization pressure was adjusted to 20 kg / cm ² -G. For another 30 minutes,
The temperature was maintained at 270-275 ° C. to complete the reaction.
Discharge is 2 liter /
Supply at a rate of time, and the steam pressure is 20 kg / cm ² -G
For 1 hour. The obtained primary condensate has an intrinsic viscosity [η] of 0.22 dl / g and a melting point of 30.
It was 0 ° C. This primary condensate was melt-highened in the same manner as in Reference Example 1 to obtain an intrinsic viscosity [η] of 1.14 d.
A white pellet of polyamide having a melting point of 318 ° C. was obtained. The discharge of the primary condensate was stable, and the above-mentioned polyamide having a high molecular weight and a high melting point (hereinafter abbreviated as PA6T / 6I) could be obtained.

Reference Example 4 (Production of Polyamide-4) 3256.2 g (19.6 mol) of terephthalic acid, 1,9
2690.9 g (17.0 mol) of nonanediamine, 2
-Methyl-1,8-octanediamine 474.9 g
(3.0 mol), 97.7 g (0.8 mol) of benzoic acid,
6.5 g of sodium hypophosphite monohydrate (0.1% by weight based on the total weight of the above four polyamide raw materials) and 2.2 liters of distilled water were put into an autoclave having an inner volume of 20 liters, and were replaced 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 the reaction was continued for 1 hour, the temperature was raised to 230 ° C., and thereafter, the temperature was maintained at 230 ° C. for 2 hours, the water vapor was gradually removed, and the reaction was performed while maintaining the pressure at 22 kg / cm ² . Next, the pressure was reduced to 10 kg / cm ² over 30 minutes, and the reaction was further performed for 1 hour.
A prepolymer of 0 dl / g was obtained. The prepolymer was dried under reduced pressure at a temperature of 100 ° C. for 12 hours,
Crushed to the following size. This was subjected to solid-phase polymerization at 230 ° C. under a pressure of 0.1 mmHg for 10 hours.
A white polyamide (hereinafter, abbreviated as PA9T) having a temperature of 08 ° C. and an intrinsic viscosity [η] of 1.00 dl / g was obtained.

Example 1 PA6T / 66 and PA9T were dried at 120 ° C. under reduced pressure for 2 hours.
Dried for 4 hours. These were dry-blended at the weight ratios shown in Table 1 and twin-screw extruder (screw diameter = 30 mm, L
/ D = 28, cylinder temperature = 310-330 ° C., rotation speed = 150 rpm) and pelletized. The obtained pellet was injection molded at a cylinder temperature of 320 ° C. and a mold temperature of 150 ° C., and various physical properties of the obtained molded product were measured. Table 1 shows the obtained results.

Example 2 PA6T / 66 and PA9T were dried at 120 ° C. under reduced pressure.
Dried for 4 hours. These were dry-blended at the weight ratios shown in Table 1, melt-kneaded and pelletized in the same manner as in Example 1. The obtained pellets were injection-molded in the same manner as in Example 1, and various physical properties of the obtained molded articles were measured. Table 1 shows the obtained results.

Example 3 PA6T / 6 and PA9T were treated under reduced pressure at 120 ° C. for 24 hours.
Dried for hours. These were dry-blended at the weight ratios shown in Table 1, melt-kneaded in the same manner as in Example 1,
Pelletized. The obtained pellets were injection-molded in the same manner as in Example 1, and various physical properties of the obtained molded articles were measured. Table 1 shows the obtained results.

Comparative Example 1 PA6T / 66 was dried at 120 ° C. under reduced pressure for 24 hours. This was melt-kneaded and pelletized in the same manner as in Example 1. The obtained pellet was injection-molded in the same manner as in Example 1, and various physical properties of the obtained molded product were measured. Table 1 shows the obtained results.

Comparative Example 2 PA6T / 6 was dried under reduced pressure at 120 ° C. for 24 hours.
This was melt-kneaded and pelletized in the same manner as in Example 1. The obtained pellets were injection-molded in the same manner as in Example 1, and various physical properties of the obtained molded articles were measured. Table 1 shows the obtained results.

[0042]

[Table 1]

Example 4 PA6T / 6I and PA9T were dried under reduced pressure at 120 ° C. for 2 hours.
Dried for 4 hours. These were dry-blended at the weight ratios shown in Table 2, melt-kneaded and pelletized in the same manner as in Example 1. The obtained pellets were injection-molded in the same manner as in Example 1, and various physical properties of the obtained molded articles were measured. Table 2 shows the obtained results.

Example 5 PA6T / 6I and PA9T were dried at 120 ° C. under reduced pressure for 2 hours.
Dried for 4 hours. These were dry-blended at the weight ratios shown in Table 2, melt-kneaded and pelletized in the same manner as in Example 1. The obtained pellets were injection-molded in the same manner as in Example 1, and various physical properties of the obtained molded articles were measured. Table 2 shows the obtained results.

Example 6 PA6T / 66, PA6T / 6I and PA9T were dried under reduced pressure at 120 ° C. for 24 hours. These were dry-blended at the weight ratios shown in Table 2, melt-kneaded and pelletized in the same manner as in Example 1. The obtained pellets were injection-molded in the same manner as in Example 1, and various physical properties of the obtained molded articles were measured. Table 2 shows the obtained results.

Comparative Example 3 PA6T / 6I was dried at 120 ° C. under reduced pressure for 24 hours. This was melt-kneaded and pelletized in the same manner as in Example 1. The obtained pellets were injection-molded in the same manner as in Example 1, and various physical properties of the obtained molded articles were measured. Table 2 shows the obtained results.

Comparative Example 4 PA6T / 66 and PA6T / 6I were dried under reduced pressure at 120
Dry at 24 ° C. for 24 hours. These were dry-blended at the weight ratios shown in Table 2, melt-kneaded and pelletized in the same manner as in Example 1. The obtained pellets were injection-molded in the same manner as in Example 1, and various physical properties of the obtained molded articles were measured. Table 2 shows the obtained results.

[0048]

[Table 2]

Example 7 PA6T / 66 and PA9T were dried at 120 ° C. under reduced pressure for 24 hours. These and glass fiber (CS3J-256S, manufactured by Nitto Boseki Co., Ltd.) were dry-blended at the weight ratio shown in Table 3, melt-kneaded in the same manner as in Example 1, and pelletized. The obtained pellets were injection-molded in the same manner as in Example 1, and various physical properties of the obtained molded articles were measured. Table 3 shows the obtained results.

Example 8 PA6T / 6 and PA9T were dried at 120 ° C. under reduced pressure for 24 hours. These and glass fiber (Nitto Boseki Co., Ltd.,
CS3J-256S) was dry-blended at the weight ratios shown in Table 3, melt-kneaded in the same manner as in Example 1,
Pelletized. The obtained pellets were injection-molded in the same manner as in Example 1, and various physical properties of the obtained molded articles were measured. Table 3 shows the obtained results.

Example 9 PA6T / 66 and PA9T were dried at 120 ° C. under reduced pressure for 24 hours. These, glass fiber (Nitto Boseki Co., Ltd., CS3J-256S), brominated polystyrene (flame retardant: Ferro Japan, Pyrocheck 68PB)
And a mixture of sodium oxide and antimony pentoxide (flame retardant aid: manufactured by Nissan Chemical Industries, Ltd., San-Epoque NA-
1070 L) were dry-blended at the weight ratios shown in Table 3, melt-kneaded and pelletized in the same manner as in Example 1. The obtained pellets were injection-molded in the same manner as in Example 1, and various physical properties of the obtained molded articles were measured. Table 3 shows the obtained results.

Comparative Example 5 PA6T / 66 and PA9T were dried at 120 ° C. for 24 hours under reduced pressure. This and glass fiber (Nitto Boseki Co., Ltd.,
CS3J-256S) was dry-blended at the weight ratios shown in Table 3, melt-kneaded and pelletized in the same manner as in Example 1. The obtained pellets were injection-molded in the same manner as in Example 1, and various physical properties of the obtained molded articles were measured. Table 3 shows the obtained results.

Comparative Example 6 PA6T / 66 was dried at 120 ° C. under reduced pressure for 24 hours. This and glass fiber (Nitto Boseki Co., Ltd., CS3J
-256S), brominated polystyrene (flame retardant: Ferro-
Japan, Pyrocheck 68PB) and a mixture of sodium oxide and antimony pentoxide (flame retardant: San-Epoque NA-1070L, manufactured by Nissan Chemical Industries, Ltd.)
Was dry-blended at the weight ratio shown in Table 3, melt-kneaded and pelletized in the same manner as in Example 1. The obtained pellets were injection-molded in the same manner as in Example 1, and various physical properties of the obtained molded articles were measured. Table 3 shows the obtained results.

[0054]

[Table 3]

[0055]

Industrial Applicability The polyamide composition of the present invention has excellent heat resistance and chemical resistance, has low water absorption, has little dimensional change due to water absorption, and is particularly suitable for electric / electronic parts and automobile parts. Suitable for.

Claims (2)

[Claims] (1) a hexamethylene terephthalamide unit (a) and a hexamethylene isophthalamide unit (b),
It comprises at least one unit selected from the group consisting of hexamethylene adipamide unit (c) and caproamide unit (d), and the ratio of each unit is one of the following formulas (1) to (3) in weight ratio. Polyamide (A) that satisfies
And a dicarboxylic acid unit containing 60 to 100 mol% of terephthalic acid units and 60 to 100 mol% of 1,9-nonanediamine unit and / or 2-methyl-1,8-octanediamine unit, and 1, A polyamide (B) comprising a 9-nonanediamine unit and a diamine unit having a molar ratio of 2-methyl-1,8-octanediamine unit of 100: 0 to 20:80, and a polyamide (A)
And a polyamide (B) in which the weight ratio satisfies the following formula (4). (A) / (b) = 55 / 45-80 / 20 (1) (a) / (c) = 20 / 80-80 / 20 (2) (a) / (d) = 55 / 45-90 / 10 (3) (B) / [(A) + (B)] × 100 ≧ 10 (4) 2. A molded article comprising the polyamide composition according to claim 1.