JP3458544B2 - Copolyamide and method for producing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copolyamide and a method for producing the same, and more particularly to a high quality copolyamide having performance such as moldability, heat resistance and chemical resistance and a method for producing the same. It is a thing.

[0002]

2. Description of the Related Art Polyamides are widely used in the fields of automobiles, electric and electronic fields, etc. by utilizing their excellent properties as engineering plastics.

Conventionally, nylon 6 and nylon 66 have been mainly used as polyamides, but in the field of microelectronics and temperature rise due to higher output of automobile engines in recent years and higher density in the engine room of automobiles. Along with the progress of miniaturization and high integration, there has been a demand for an ultra-thin material for molded products that can withstand use in a high temperature atmosphere. However, the melting points (Tm) of nylon 6 and nylon 66 are 220 ° C. and 260 ° C., respectively, and even when reinforced with glass fiber, the limit of the heat distortion temperature is up to their respective melting points.

Recently, many polyamide resin compositions containing terephthalic acid, compositions thereof, or glass fiber reinforced products thereof have been proposed as polyamide resin compositions capable of withstanding use under these high temperature atmospheres (JP-A-59). -161
No. 428, No. 59-155426, No. 59-53536, and No. 62-156130.
Issue Bulletin).

However, polyamides containing terephthalic acid have conventionally been problematic in terms of moldability and color tone, and also have high mechanical strength such as elongation, strength, bending strength and bending elastic modulus and heat deformability. In terms of aspect, it was not satisfactory. There is also a problem that the manufacturing process itself is prone to trouble. In order to solve such a problem, attention has been paid to a polyamide polymerization method, and various methods have been proposed.

From the viewpoint of reducing thermal history, the following polymerization methods have been proposed. JP-A-60-2068
No. 27, a continuous polymerization carried out at high pressure in a short time, JP
No. 41318 proposes continuous polymerization in a short time using a special apparatus, but it is difficult to switch the product type, and development of a versatile polymerization method has been desired.
Batch polymerization is an easy method to switch the variety, and there are some studies.

Japanese Unexamined Patent Publication (Kokai) No. 5-170895 and Japanese Unexamined Patent Publication (Kokai) No. 5
In JP-9381, a polyamide is obtained by forming a primary condensation product having a low degree of polymerization under the conditions of high pressure and 250 ° C. As shown in JP-A-5-170895, in batch polymerization, there is a problem of precipitation as a solid phase in a polymerization tank. In order to prevent this, polymerization is carried out at a low temperature of 250 ° C. or lower, or 23 kg / cm ² − Polymerization at high pressures above G has been required. Since the primary condensate thus obtained has a low relative viscosity, it is subjected to a large heat load when the degree of polymerization is increased, and as a result, polymer color tone, crystallinity, melt stability, etc. are reduced to obtain a high-quality polyamide. I couldn't.

As the polymerization degree increasing step, a method of carrying out solid phase polymerization for a long time (JP-A-2-41318) or a method of increasing the polymerization degree in a molten state at a high temperature by using an extruder (JP-A-HEI-3) -43417, JP-A-3-17156,
JP-A-59-155433 and JP-A-5-4368.
No. 1) has been proposed.

The method in which the degree of polymerization is increased by solid phase polymerization has a problem that the process requires a very long time. On the other hand, in the method of increasing the degree of polymerization in the molten state, a high temperature is required, so that thermal deterioration easily occurs, and as a result, problems such as deterioration of color tone, lowering of mechanical strength, and lowering of moldability are likely to occur. In JP-A-3-43417, tetrakis (2,4-di-t-butylphenyl) -4,4'-biphenylene phosphonite is used as a heat resistance stabilizer when the degree of polymerization is increased. However, the heat history was not sufficiently improved because the test was carried out under the conditions of 340 to 345 ° C.

In view of such a conventional technique, the invention of the present application has reached the configuration described later.

In Japanese Patent Laid-Open No. 3-17156 and Japanese Patent Laid-Open No. 59-155433, an extruder is used to increase the degree of polymerization in continuous polymerization. Other than that, no measures for reducing the heat history by screws or forced degassing are shown.

Further, in Japanese Unexamined Patent Publication No. 5-43681,
Although a phosphoric acid compound is used as a catalyst for increasing the degree of polymerization to increase the polymerization rate, an essential solution such as degassing of condensed water has not been taken because an atmospheric vent is used. In addition, the residence time of the reaction was long and thermal deterioration occurred, so that it was not possible to obtain those having satisfactory characteristics.

Further, in such a copolyamide, the relationship between the chain distribution of amide bonds, crystallization behavior and desired properties has not been known.

[0014]

SUMMARY OF THE INVENTION The present invention is directed to tensile strength,
It is an object of the present invention to provide a copolyamide capable of sufficiently exhibiting properties such as tensile elongation, flexural strength, flexural modulus, chemical resistance, and heat distortion temperature, and a method for producing the same.

[0015]

[Means for Solving the Problems] In view of the above situation, the inventors of the present invention have conducted intensive studies in order to solve the above-mentioned problems by paying attention to the chain distribution and crystallization behavior of amide bonds, and as a result, the melt stability and the color tone have been improved. Have found a terephthalamide amide-containing copolyamide having excellent mechanical properties and high practical value, and a method for producing the same. That is, the present invention provides (1) "4 carbon atoms.
~ 14 has an amide bond formed from an aliphatic diamine and terephthalic acid, the chain distribution abundance ratio of the amide bond satisfies the formulas (A) and (B), and the semi-crystallization time is represented by the formula (C ) Is satisfied, a copolyamide. 0.9 ≦ [XY] obs ./ [XY] calcd. ≦ 1.1 (A) 0.9 ≦ [XX] obs ./ [XX] calcd. ≦ 1.1 (B) 4.4-0.1 (Tm− T) ≤ logt _1/2 ≤ 5.5-0.1 (Tm
-T) (C) "and (2)" The maximum ultimate pressure is 5k.
g / cm ² (493.4615 kPa) -G or more 23 k
g / cm ² (2269.9229 kPa) -less than G, and after forming a primary condensate under the condition that the highest temperature reached exceeds 260 ° C. and 330 ° C. or less, {screw length L}
/ {Outermost diameter D of screw} Using a twin-screw extruder including a screw segment having a screw segment of 2 or less, it is melt-extruded to have a high degree of polymerization, and an aliphatic diamine having 4 to 14 carbon atoms and terephthalate. An amide bond formed from an acid, the chain distribution abundance ratio of the amide bond satisfies the formulas (A) and (B), and the half crystallization time is represented by the formula (C).
A method for producing a copolyamide that satisfies the requirements. 0.9 ≦ [XY] obs ./ [XY] calcd. ≦ 1.1 (A) 0.9 ≦ [XX] obs ./ [XX] calcd. ≦ 1.1 (B) 4.4-0.1 (Tm− T) ≦ logt _1/2 ≦ 5.5-0.1 (Tm-T) (C) ”. (Here, X is an amide bond formed from an aliphatic diamine having 4 to 14 carbon atoms and terephthalic acid,
Y means an amide bond other than X. [XY] is the proportion of X and Y adjacent to each other in the polymer structure with respect to all amide bonds, and [XX] is X and X with respect to all amide bonds.
Indicates the ratio of adjacent to each other in the polymer structure. [XY] ca
lcd. and [XX] calcd. are calculated as a statistically random linkage distribution of X and Y amide bonds [XY]
And [XX], and [XX] obs. And [XX] obs. Are the respective values of [XY] and [XX] measured from the copolyamide. Here, t _1/2 is a half-crystallization time (second), Tm is a melting point (° C.) of the copolyamide, and T is a measurement temperature (° C.) of the half-crystallization time. log is a common logarithm. )

The details of the present invention will be described below.

The copolyamide of the present invention has 4 to 4 carbon atoms.
It is a copolyamide containing an amide bond consisting of 14 aliphatic diamines and terephthalic acid. The melting point of the copolyamide of the present invention is preferably 260 to 320.
C., more preferably 270 to 310.degree. This range is preferable, when the melting point is low, the heat-resistant resin which is the object of the present invention cannot be obtained, and when the melting point is too high, a high temperature is required during the processing of the resin. This is because there is a problem such as foaming due to the decomposition reaction.

Specific examples of the aliphatic diamine having 4 to 14 carbon atoms include 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,5-diamino-2-methylpentane, 1,7-diaminoheptane,
1,8-diaminooctane, 1,9-diaminononane,
It is an aliphatic alkylenediamine such as 1,10-diaminodecane, 1,11-diaminoundecane, 1,12-diaminododecane, 1,13-diaminotridecane and 1,14-diaminotetradecane. Of these aliphatic diamines, long-chain aliphatic diamines having a particularly large number of carbon atoms are preferably used in order to reduce the water absorption of the obtained polyamide. These aliphatic diamines can be used alone or in combination of two or more. In particular, the aliphatic diamine component having 4 to 14 carbon atoms has 6 carbon atoms, that is, 1,6-diaminohexane or 1,5
-The copolymerized polyamide produced by diamino-2-methylpentane has excellent balance between heat resistance and crystallinity, and is preferably used.

In the copolymerized polyamide of the present invention, the starting material for the amide structural unit forming the remaining portion of the terephthalamide structural unit is, for example, ε-caprolactam, ζ-enanthlactam, η-capryllactam, ω.
-Lactams such as laurolactam, said diamines,
1,15-diaminopentadecane, 1,16-diaminohexadecane, 1,17-diaminoheptadecane, 1,
Aliphatic alkylenediamines having 15 to 18 carbon atoms such as 18-diaminooctadecane, aromatic diamines such as phenylenediamine, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, Examples include sebacic acid, undecanedioic acid, dodecanedioic acid, prasiric acid, tetradecanedioic acid, pentadecanedioic acid, octadecanedioic acid, and other aliphatic dicarboxylic acids having 2 to 18 carbon atoms, and aromatic dicarboxylic acids such as isophthalic acid. Of the amide structural units derived from these,
In the present invention, caproamide, hexamethylene adipamide and hexamethylene isophthalamide are preferably used alone or in combination.

When 1,6-diaminohexane is used as the aliphatic diamine component of the terephthalic acid amide structural unit, the structural unit (I)

[Chemical 9] (Hexamethylene terephthalamide unit (hereinafter referred to as 6T)), and at least one structural unit selected from structural units (II) to (IV),

[Chemical 10] (Hexamethylene adipamide unit (hereinafter referred to as 66)),

[Chemical 11] (Hexamethylene isophthalamide unit (hereinafter referred to as 6I)),

[Chemical 12] A 6T-containing copolyamide having a repeating unit consisting of (caproamide unit (hereinafter referred to as 6)) is preferable.

In the above 6T-containing copolyamide,
For example, when the composition of a two-component copolymer is 6T / 6I, the copolymerization ratio is 45 / in terms of the weight ratio in the raw material stage.
55-80 / 20, preferably 55 / 45-80 / 2
0, more preferably 60/40 to 75/25. When the copolymerization composition is 6T / 66, the copolymerization ratio is 20/80 to 80 in terms of weight ratio in the raw material stage.
/ 20, preferably 30/70 to 70/30, and more preferably 30/70 to 60/40. When the copolymer composition is 6T / 6, the copolymerization ratio in the raw material stage is 40/60 to 90/10 by weight, preferably 55/45 to 85/15, and more preferably 60/4.
It is in the range of 0 to 80/20. The copolymerization ratio of these 6T-containing copolyamides is such that the polymer melting point is 260 ° C to 320 ° C.
It may be chosen to give a crystalline copolyamide in the range of ° C. 6T / 6I, 6T / 66 and 6T / 6
The copolymerization ratio in the raw material stage is 4 for each weight.
When the amount of 6T is smaller than that of 5/55, 20/80, or 40/60, it is not preferable in that the polymer melting point is lowered, the heat resistance is lowered, such as the heat distortion temperature, and the 6T content is reduced, so that the water absorption is increased. Also, 6T / 6I, 6T / 66 and 6
The copolymerization ratio in the raw material stage of T / 6 is 80 /
When the amount of 6T is larger than 20, 80/20, 90/10, the melting point of the polymer is increased and the heat resistance is improved, but the processing temperature is increased and the polymer is thermally decomposed, which is not preferable. Among these copolymerized polyamides, 6T / 66 is particularly preferable from the viewpoint of crystallization characteristics, and the copolymerization ratio is 35% by weight.
A copolyamide in the range of / 65 to 60/40, particularly 37/63 to 50/50 can realize excellent properties.

The 6T-containing polyamide of the present invention may be a copolymer of three or more components, and specific examples of preferable copolymerization composition are 6T / 66 / 6I,
Mention may be made of compositions containing 6T / 66 such as 6T / 66/6. 6 in these copolyamides
The T / 66 component is preferably 50% by weight or more,
Further, it is preferably 60% by weight or more, particularly preferably 70% by weight or more, and further preferably 95% by weight or more.

Further, as the aliphatic diamine having a terephthalic acid amide structural unit, a diamine having 12 carbon atoms is also preferably used, and in that case (hereinafter, a binding unit with terephthalic acid is referred to as 12T hereinafter), hexamethylene adipamide is used. A 12T-containing polyamide in which repeating units such as units, dodecamethylene adipamide units, hexamethylene isophthalamide units, dodecamethylene isophthalamide units, and caproamide units are copolymerized is preferably used.

The copolymerized polyamide of the present invention is substantially a random copolymer, and the chain distribution abundance ratio of amide bonds satisfies the formulas (A) and (B). 0.9 ≦ [XY] obs ./ [XY] calcd. ≦ 1.1 (A) 0.9 ≦ [XX] obs ./ [XX] calcd. ≦ 1.1 (B) [where X is An amide structural unit formed from an aliphatic diamine having 4 to 14 carbon atoms and terephthalic acid, and Y is X
Means an amide structural unit other than. When it is composed of three or more structural units, all amide structural units other than X are considered to be the same and designated as Y. In addition, X like 6T / 12T
When there are two or more components corresponding to, one component unit is X and the other is Y. [XY] is the proportion of X and Y adjacent to each other in the polymer structure, and [XX] is the proportion of X and X adjacent to the total number of structural units in the polymer structure. In [XY] calcd. And [XX] calcd., The structural units of X and Y are calculated as a statistically random linkage distribution [XY] and [X].
[XY] obs. And [X].
X] obs. Is measured from the copolyamide [XY]
And the values of [XX]. The chain distribution abundance ratio of the structural units preferably satisfies the formulas (D) and (E). 0.95 ≦ [XY] obs ./ [XY] calcd. ≦ 1.05 (D) 0.95 ≦ [XX] obs ./ [XX] calcd. ≦ 1.05 (E)

When the chain distribution abundance ratio of the structural units is outside the ranges of the formulas (A) and (B), the block property is strong, so that the random copolymer has excellent mechanical properties, for example, balance between tensile strength and elongation, In addition, the characteristics such as heat distortion temperature are impaired.

The semi-crystallization time of the copolymerized polyamide of the present invention satisfies the formula (C). 4.4-0.1 (Tm-T) ≤ logt _1/2 ≤ 5.5-0.1 (Tm-T) (C) [where t _1/2 is the half crystallization time (seconds) and Tm is the copolyamide. It is a melting point (° C.), T is a measurement temperature (° C.) of the half-crystallization time, and means a range from a temperature 35 ° C. lower to a temperature 25 ° C. lower than the melting point of the copolyamide. Further, it is particularly preferable that the half-crystallization time of the copolyamide satisfies the formula (F). 4.6-0.1 (Tm-T) ≤ logt _1/2 ≤ 5.3-0.1 (Tm-T) (F) Where logt _1/2 is less than 4.4-0.1 (Tm-T) The toughness is insufficient and 5.5-0.
If it exceeds 1 (Tm-T), the crystallization time is long and molding in a fast molding cycle (particularly mold releasability during molding) becomes difficult, so the above range is used. As the temperature for measuring the half crystallization time, a temperature lower than the melting point of the copolyamide by 30 ° C. is preferably used.

The copolyamide of the present invention can be produced by the following method. For example, it is a two-stage polymerization method in which a primary condensate is formed under specific conditions and then melt-extruded by a twin-screw extruder having a specific screw segment to increase the degree of polymerization. First, the method for forming the primary condensate will be described.

The primary condensate is prepared by charging an aqueous solution of a salt consisting of a monomer, a diamine and a dicarboxylic acid, which gives the above-mentioned copolymerization composition, into a pressure polymerization tank or the like and polymerizing it as a solution using water as a solvent under stirring conditions. Obtained by reacting. The concentration of the raw material charged in the solution is 5% by weight or more, preferably 15% by weight or more and 90% by weight or less, preferably 85% by weight or less.

The primary condensate is formed by raising the temperature and pressure under stirring conditions. The polymerization temperature is raised and controlled within a range from the temperature after the charging or after the concentration step described below, which is performed as necessary, to the highest reached temperature. Further, the polymerization pressure is controlled below the maximum ultimate pressure according to the progress of polymerization. The highest temperature and the highest pressure do not have to be at the end of the polymerization and may be at any time until the completion of the polymerization.

In the polymerization of the above primary condensate, the maximum ultimate pressure is 5 kg / cm ² (493.4615 kPa) -G or more 23 kg / cm ² (2269.9229 kPa) -G
If it is less than 10 kg / cm ² (9
86.923 kPa) -G or more, 22 kg / cm ² (2
171.2306 kPa) -G or less, preferably 20 k
g / cm ² (1973.846 kPa) -G or less. When it is 23 kg / cm ² -G or more, the water content in the reaction system becomes high, so that there is a problem that the increase in the degree of polymerization is poor and the reaction rate to the primary condensate is insufficient. The maximum ultimate pressure is 5
If it is less than kg / cm ² -G, there is a risk that the primary condensate will precipitate in the polymerization tank.

The maximum temperature reached in the formation of the primary condensate is more than 260 ° C and 330 ° C or less, but 260 ° C when the melting point of the target copolyamide is less than 280 ° C.
The temperature is generally higher than 300 ° C and lower than 300 ° C, preferably lower than 290 ° C. The melting point of polyamide is 280 to 320 ° C.
In such a case, the melting point of the copolyamide is less than minus 20 ° C, preferably not less than minus 15 ° C and not more than plus 10 ° C, preferably not more than plus 5 ° C. If the maximum temperature reached is 260 ° C. or lower, not only is it insufficient to increase the degree of polymerization of the primary condensate,
Due to the difference in the reactivity of each of the copolymerization components, a primary condensate having an extremely high chain distribution of chain distribution is obtained, and even if the degree of polymerization of this is increased, the obtained polymer still has the block property. On the other hand, if the maximum temperature reached exceeds 330 ° C., the thermal history of the copolyamide becomes too large and various properties are deteriorated, which is not preferable.

Further, after the primary condensate is formed, the discharge is carried out, but the discharge is preferably carried out under the pressure of steam. The steam pressure may be equal to or lower than the maximum ultimate pressure in the formation of the primary condensate, but the maximum ultimate pressure minus 10 k.
It is preferably g / cm ² (986.923 kPa) -G or more and not more than the ultimate pressure. The steam pressure is preferably maintained during discharge, and it is preferable to supply water or steam into the polymerization tank and maintain a constant steam pressure during discharge, or discharge while increasing the pressure. When water, preferably ion-exchanged water, is supplied from the outside of the system to the polymerization tank by a metering pump, it is preferable to preheat and supply the water via a heat exchanger. The heating temperature is preferably 100
℃ or more, more preferably 150 ℃ or more. It is more preferable that the heating temperature is the saturated steam temperature of the pressure in the polymerization tank in order to maintain the stability of the polymerization state. When steam is supplied into the polymerization tank from outside the system, the pressure of the steam generating boiler must be higher than the pressure in the polymerization tank. The maximum temperature reached during discharge is -10.
It is preferable that the temperature is maintained at not less than 0 ° C and not more than the highest reached temperature.

The formation and discharge of the primary condensate according to the present invention may be within the ranges of the highest temperature and the highest pressure shown above. As shown in Japanese Patent Application Laid-Open No. 5-170895, it is known that there exists a region where a primary condensate precipitates and solidifies under conditions of high temperature and low pressure. Polymerization at a high pressure and a low temperature while avoiding such a precipitation-solidified region is not preferable because the reaction does not proceed sufficiently. In the invention of the present application, the polymerization condition of the primary condensate, which is higher in temperature and lower in pressure than before, that is, the reaction is terminated before the primary condensate is precipitated, is preferably used even under the condition that precipitation and solidification may occur. The temperature and pressure regions of precipitation and solidification are determined by the composition of polyamide, temperature, pressure and time. For example, 66 / 6T =
The formation of the primary condensate at 50/50% by weight results in room temperature, atmospheric pressure to 265 ° C., 27 kg / cm ² (26664.692).
1 kPa) -G is quickly raised in temperature and pressure is maintained for about 5 hours, and then precipitation and solidification are started. Also, at 265 ° C., 22 kg / cm ² (2171.2
306 kPa) -G, the temperature is raised rapidly and the pressure is maintained, and if the temperature is maintained under that condition, precipitation solidification starts after about 2 hours.
Even under such conditions, if the polymerization is completed and discharged in less than 2 hours from the start of holding the conditions, precipitation solidification does not become a problem. As described above, even in the precipitation-solidified region, the reaction can be performed if the time required for precipitation is not reached. The time in the region of the conditions of precipitation and solidification is preferably 0.1 hours shorter than the time to start the precipitation, further 0.2 hours shorter, and further 0.5 hours shorter. Further, the total polymerization time (polymerization and discharge) is 10 hours or less, preferably 7 hours or less, more preferably 5 hours or less, and particularly preferably 4 hours or less.

As a method for avoiding precipitation and solidification during polymerization, it is effective to stir the side surface of the polymerization tank efficiently. The distance between the stirring blade and the polymerization tank is preferably 10% or less, and more preferably 5% or less, with respect to the radius of the polymerization tank. Where the distance between the stirring blade and the polymerization tank is 10% or less with respect to the radius of the polymerization tank, it is preferable that the blade is rotating and occupy 70% or more of the side surface below the liquid surface of the polymerization tank. It is preferably 80% or more and less than 100%. Precipitation and solidification can be delayed by efficiently stirring the side surface of the polymerization tank, which easily reacts by heating.

If necessary, a salting step and / or a concentrating step may be carried out before the polymerization of the primary condensate. The salt tone is a step of producing a salt from a dicarboxylic acid component and a diamine component, and is in the range of the pH of the neutralization point of the salt of ± 0.5, and further, of the pH of the neutralization point of the salt of ± 0.3. It is preferable to adjust the range. Concentration is the value of the concentration of the raw material charging solution plus 2 to 90% by weight, more preferably plus 5
It is preferred to concentrate to a concentration of ~ 80% by weight. The temperature of the concentration step is preferably 90 to 220 ° C, more preferably 100 to 210 ° C, and 130 to 20 ° C.
0 ° C. is particularly preferred. Pressure in the concentration step is 0 to 20 kg /
cm ² (0 to 1973.846 kPa) -G, preferably 1 to 10 kg / cm ² (9.86923 to 98.69).
23 kPa) -G. Usually, the concentration pressure is controlled below the pressure for forming the primary condensate. Further, in order to accelerate the concentration, it is possible to perform the forced discharge of the solvent by, for example, a nitrogen stream. The concentration step is effective in shortening the polymerization time.

The relative viscosity of a 1% sulfuric acid solution of the primary condensate at 25 ° C. (JIS-K6810 method) was 1.15.
Is preferably 2.5 to 2.5, more preferably 1.2 or more, preferably 1.3 or more, more preferably 1.4 or more, 2.3 or less, preferably 2.0 or less, more preferably 1. It is 8 or less. When the relative viscosity is less than 1.15,
A primary condensate having an extremely high blocking property is likely to be formed, and it is necessary to prolong the polymerization time for increasing the degree of polymerization and to raise the temperature, so that the thermal history given to the copolyamide becomes large. On the other hand, if the relative viscosity exceeds 2.5, the melt viscosity of the primary condensate becomes too high, which causes ejection failure during ejection after the formation of the primary condensate, which is not preferable. The water content of the primary condensate is 20% by weight or less, preferably 10% by weight or less, and more preferably 5% by weight or less. If it exceeds 20% by weight, it becomes difficult to increase the degree of polymerization. The moisture content can be controlled by discharging the primary condensate in water and then drying it, or by cooling the discharged high-temperature primary condensate with cooling water and evaporating it using the heat of the primary condensate. It is generally controlled. In addition, the primary condensate is preferably crushed to an appropriate size before increasing the degree of polymerization.

As an example of a suitable apparatus for producing the primary condensate, a batch reaction tank or a batch reaction apparatus of 1 to 3 tank type in series can be mentioned.

Next, a method of melt extruding the primary condensate to increase the degree of polymerization will be described.

The extruder used in the step of increasing the degree of polymerization of the primary condensate in the present invention is a twin-screw extruder including a screw segment having L / D of 2 or less. Here, L represents the length of the screw segment, and D represents the outer diameter, that is, the outermost diameter when the screw segment is rotated. By using a short screw segment having L / D of 2 or less, the state of the polymer in the cylinder can be finely controlled, and a high quality copolyamide can be obtained. In particular, for the purpose of making the copolyamide a random structure without undergoing thermal deterioration, it is sufficiently kneaded while controlling the state in the cylinder with a short L / D screw segment, and vacuum degassing is carried out to quickly achieve high polymerization. It is necessary to be refined. L
The ratio of the screw segment having / D of 2 or less is preferably 5% or more and 100% or less, further 30% or more, and further preferably 50% or more with respect to the entire length of the screw.

The screw segments constituting the screw of the twin-screw extruder include a resin feed segment and a mixing segment, and a forward full flight segment is preferably used as the resin feed segment. Mixing segments include rotor, notched rotor, forward kneading, orthogonal kneading, reverse kneading, kneading neutral, gear kneading, pineapple kneading, twist kneading, reverse full flight, and notch flight. It is preferable to use one kind or a combination of two or more kinds. Further, as other segments, there are a seal ring, a torpedo ring, etc., and it is effective to use them appropriately. The forward full flight segment includes all of the forward full flight structures, and for example, those having different flight pitches, those having a sharp flight or those having a wide flight can also be used. Further, from the viewpoint of controlling the polymerization reaction, it is effective to use one or more, preferably two or more reverse full flight segments. The segments other than the forward full flight may be arranged in one part or divided into some parts. By using a segment other than the normal full flight, the polymerization reaction can be effectively promoted. The L / D of the forward full flight and the segment other than the forward full flight are selected so as to match the ratio of the screw segment having the L / D of 2 or less described above, but the L / D of the segment other than the forward full flight is 2 The following segments are preferably included, and L / D is 0.2 or more.
It is even more preferred that it contains 8 or less.

The total length of the segments other than the forward full flight is 0% or more, further 3% or more, further 5% or more, while 70% or less, further 50% or less, or further, with respect to the entire length of the screw. Is preferably used in the range of 45% or less. The number of threads of the screw may be any, but 1, 2, 3 threads are preferable, and 2 threads are particularly preferable.
The groove type may be either a shallow groove or a deep groove, but a deep groove is more preferable.

The twin-screw extruder in the present invention may be rotated in the same direction or in different directions, but the one rotating in the same direction is preferable from the viewpoint of easy control of polymerization conditions.
The rotation speed is 50 rpm or more, preferably 70 rpm or more,
It is 800 rpm or less, preferably 500 rpm or less. A larger rotation number is better for shearing and stirring, and further for renewing the resin surface for degassing the condensation water, but if it is too large, the shear heat generation will become too large and the resin will be deteriorated. It is preferable to select the number of rotations.

The L / D of the entire screw of the twin-screw extruder used in the present invention is not particularly limited, but is usually set to 10 or more, preferably 15 or more, 100 or less, preferably 70 or less. . If it is smaller than 10 or larger than 100, it becomes difficult to proceed the polymerization stably.

Next, the extrusion conditions for increasing the degree of polymerization by the extruder in the present invention will be shown.

In the present invention, the degree of polymerization is increased by the extruder by using the above-mentioned twin-screw extruder while performing vacuum deaeration using the formula (G).
It is preferable to carry out within the range of the residence time that satisfies t ≦ 5000 × Δηr / (T R -280) (G) (t: retention time (seconds)) (Δηr: variation in relative viscosity due to high degree of polymerization) (T _R: resin at the time of high degree of polymerization (Maximum ultimate temperature (° C.)) Further, it is preferable to increase the degree of polymerization within the range of the residence time that satisfies the formula (H). 20 ≦ t ≦ 4000 × Δηr / (T _R −280) (H) Generally, the residence time of the extruder has a distribution, but here, it means the shortest residence time in the extruder. It is preferable that the residence time is within the above range, because if excessive heat is applied at the time of increasing the polymerization degree, the physical properties are deteriorated due to thermal deterioration, and if it is too short, the polymerization degree does not increase. The amount of change in relative viscosity (Δηr) due to the increase in the degree of polymerization is preferably 0.2 or more, more preferably 0.5 or more. When the polymerization degree is high, the maximum temperature the resin reaches is higher than the melting point, preferably the melting point plus 1.
The temperature is 0 ° C or higher and 350 ° C or lower, preferably 340 ° C or lower. If the maximum temperature is too high, the thermal load is large even if the residence time is short, which is not preferable. In particular, it is important to keep the temperature at 350 ° C. or lower in order to prevent thermal decomposition and thermal deterioration of the polymer.

In the present invention, the vacuum degassing at the time of increasing the degree of polymerization by the extruder is carried out from one or more vents,
The shape of the vent may be any. The vacuum deaeration is for shifting the chemical equilibrium by removing the water generated by the polymerization, and it is important to perform it efficiently so as to increase the degree of polymerization within a certain residence time. Therefore, the degree of vacuum of the vent is -500 mmHg (-66.6).
61 kPa) or less, preferably -600 mmHg (-7
9.9932 kPa) or less. Further, in addition to the above-described vent having the degree of vacuum, a vent having a low degree of vacuum or an atmosphere vent may be used in combination.

The degree of polymerization of the copolyamide of the present invention is not particularly limited, and it is practical that the relative viscosity (ηr) of a 1% sulfuric acid solution at 25 ° C. is usually in the range of 1.8 to 5.0. And those in the range of 2.0 to 3.5 are preferable.

In ordinary polyamide polymerization, it is common to charge the raw materials so that the total amount of carboxyl groups and the total amount of amino groups contained in the monomer and the dicarboxylic acid / diamine salt are equal. It is also possible to prepare a polyamide having a large amount of terminal carboxyl groups or terminal amino groups by adding an excess of dicarboxylic acid component or diamine component when charging the raw materials. Further, in the polymerization reaction of the present invention, a polymerization degree adjusting agent can be added in order to facilitate the adjustment of the polymerization degree of the polyamide and the adjustment of the polymerization degree when the polymerization degree is increased. As the polymerization degree regulator, usually, a monoamine compound and a monocarboxylic acid compound are used, preferably acetic acid,
Benzoic acid, stearic acid, particularly preferably acetic acid,
Benzoic acid.

A phosphorus-based catalyst can be used in the polymerization of the present invention. For example, hypophosphite, phosphate, hypophosphorous acid, phosphoric acid, phosphoric acid ester, polymetaphosphoric acid, polyphosphoric acid, phosphine oxides, phosphonium halogen compounds and the like are preferable, hypophosphite, phosphate , Hypophosphorous acid and phosphoric acid are particularly preferably used. Specific examples of the hypophosphite include, for example, sodium hypophosphite, potassium hypophosphite, calcium hypophosphite, magnesium hypophosphite, aluminum hypophosphite, vanadium hypophosphite, hypophosphite. Manganese acid, zinc hypophosphite, lead hypophosphite, nickel hypophosphite, cobalt hypophosphite, ammonium hypophosphite and the like are preferable, and sodium hypophosphite, potassium hypophosphite, hypophosphite, etc. Calcium phosphate and magnesium hypophosphite are particularly preferred. Examples of the phosphate include sodium phosphate, potassium phosphate, potassium dihydrogen phosphate, calcium phosphate, vanadium phosphate, magnesium phosphate, manganese phosphate, lead phosphate, nickel phosphate, cobalt phosphate, and phosphoric acid. Ammonium, diammonium hydrogen phosphate and the like are preferable. As the phosphoric acid ester, for example,
Examples include ethyl octadecyl phosphate. Examples of polymetaphosphoric acids include sodium trimetaphosphate, sodium pentametaphosphate, sodium hexametaphosphate, polymetaphosphoric acid, and the like. Examples of polyphosphoric acids include sodium tetrapolyphosphate and the like. As phosphine oxides,
Examples include hexamethylphosphoramide. The addition amount of the phosphorus-based catalyst is the polyamide 100
0.0001 to 5 parts by weight is preferable with respect to parts by weight,
0.001-1 weight part is more preferable. Further, the addition time may be any time until the completion of the high degree of polymerization, but it is preferably from the time of charging the raw materials to the completion of the polymerization of the primary condensate. Moreover, you may add many times. Further, different phosphorus-based catalysts may be added in combination.

A filler may be further added to the copolyamide of the present invention to form a composition. As the filler, glass fiber or glass beads, talc, kaolin, wollastonite, mica, silica, alumina, diatomaceous earth, clay, gypsum, red iron oxide, graphite, titanium dioxide, zinc oxide, copper, stainless steel powder and the like Alternatively, plate-like inorganic compounds, other polymer fibers (carbon fibers), etc. are exemplified, and glass fibers are preferable.
Particularly preferred as glass fibers are glass rovings, glass chopped strands and the like made from strands of continuous long fibers having a diameter of about 3 to 20 μm. When such a filler is used, the compounding ratio is usually 1 part by weight or more, preferably 10 parts by weight or more and 200 parts by weight or less, preferably 15 parts by weight with respect to 100 parts by weight of the polyamide resin composition.
The amount is 0 parts by weight or less, more preferably 100 parts by weight or less. When the blending ratio of the filler exceeds 200 parts by weight, the fluidity at the time of melting is deteriorated, it is difficult to injection-mold a thin-walled molded product, and the appearance of the molded product is deteriorated, which is not preferable. The method of adding the filler to the copolyamide of the present invention is not particularly limited, and any known method can be used. Specific examples of the compounding method include a method in which a filler is dry blended with polyamide pellets, and the resulting mixture is melt-kneaded with a single-screw or twin-screw extruder. Further, when the polymerization degree is increased in the melting machine, a method of adding a filler from the middle of the melting machine is also possible.

The copolymerized polyamide of the present invention may contain a catalyst, a heat stabilizer, a catalyst, a heat stabilizer, and the like at the stage of polymerization of primary condensate, high degree of polymerization of melt, compound or molding process.
A weather resistance stabilizer, a plasticizer, a release agent, a lubricant, a crystal nucleating agent, a pigment, a dye, another polymer and the like can be added. These additives include heat-resistant stabilizers (hindered phenol-based, hydroquinone-based, phosphite-based and substitution products thereof, copper iodide, potassium iodide, etc.), weather-resistant stabilizers (resorcinol-based, salicylate-based, benzoic acid-based Triazole-based, benzophenone-based, hindered amine-based), release agents and lubricants (montanic acid and its metal salts, their esters, their half esters, stearyl alcohol, stearamide, various bisamides, bisurea and polyethylene wax, etc.), pigments (sulfurized) Cadmium, phthalocyanine, carbon black, etc.), and dyes (such as nigrosine), other polymers (other polyamides, polyesters, polycarbonates, polyphenylene ethers, polyphenylene sulfides, liquid crystal polymers,
Polyethersulfone, ABS resin, SAN resin, polystyrene, acrylic resin, polyethylene, polypropylene, ethylene / α-olefin copolymer, ionomer resin, SBS, SEBS, etc.).

A composition obtained by blending the copolyamide of the present invention and the above-mentioned reinforcing material, filler, additive and the like,
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, capacitor cases, motors Internal parts, small motor cases, gear cams, dancing pulleys, spacers, insulators, fasteners, buckles, wire clips, bicycle wheels, casters, helmets, terminal blocks, electric tool housings, starter insulation parts, spoilers, canisters, Radiator tank, chamber tank, reservoir tank, fuse box, air cleaner case, air conditioner fan, terminal housing, wheel cover, intake and exhaust pipes Bearing retainers, cylinder head covers, intake manifolds, water pipe impellers, engine roll dampers, clutch releases, speaker diaphragms, heat-resistant containers, microwave oven components, rice cooker components, printer ribbon guides, and other electrical / electronic-related components, automobiles・ Vehicle related parts, household / office electrical products parts, computer related parts, facsimile / copier related parts, machine related parts, and other various applications.

[0053]

The present invention will be described in more detail with reference to the following examples. The properties in the examples and comparative examples were measured by the following methods. 1) Melting point (Tm) Using DSC (PERKIN-ELMER7 type), samples 8 to 10
The temperature showing the maximum value of the melting curve obtained by measuring mg at a temperature rising rate of 20 ° C./min is defined as (T ₁ ). Sample 8
-10 mg is heated at a temperature rising rate of 20 ° C / min to give T ₁ +2.
Hold at 0 ° C. for 5 minutes, then cool to 30 ° C. at a cooling rate of 20 ° C./min, hold at 30 ° C. for 5 minutes, then repeat 2
Heat to T ₁ + 20 ° C. at a heating rate of 0 ° C./min.
The maximum value of the melting curve at this time was defined as the melting point (Tm). 2) Relative viscosity According to JIS K6810, 1 g of a sample was dissolved in 100 ml of 98% concentrated sulfuric acid, and the relative viscosity at 25 ° C was measured. Hereinafter, the relative viscosity is abbreviated as ηr. 3) Residence time When the polymerization degree was increased by the extruder, a coloring pigment was added from the feeder, and the time until the molten polymer started to be colored was measured. 4) Color tone Y using a color computer manufactured by Suga Test Instruments Co., Ltd.
The I value was measured. 5) Tensile strength and tensile elongation Measured according to ASTM D638. 6) Flexural strength and flexural modulus Measured according to ASTM D790. 7) Chemical resistance (LLC resistance) ASTM No. 1 dumbbell is 50% by weight of LLC (Toyota genuine long life coolant, manufactured by Toyota Motor Corporation)
After being immersed in an aqueous solution and treated in an autoclave at 130 ° C. for 500 hours, the tensile strength was measured according to ASTM D638. 8) Heat distortion temperature (DTUL) Load according to ASTM D648 4.6 kgf / cm
² (453.98458 kPa). 9) Samples 8 to 10 using semi-crystallization time DSC (PERKIN-ELMER7 type)
melting point (Tm) plus 2 at a temperature rising rate of 20 ° C./min
After raising the temperature to 0 ° C and holding it for 5 minutes, it is rapidly cooled to the measurement temperature (T) of the half-crystallization time, and the time (seconds) to the endothermic peak
_Was measured as t _1/2 . 10) Chain distribution abundance ratio of structural units JNR-GSX400, FT-NMR (JEOL Ltd.) was used to dissolve 100 mg of a sample in 0.7 ml of a hexafluoroisopropanol / deuterated benzene mixed solution, and ¹³ C- The NMR measurement was performed. The measurement sensitivity was maximized, and the abundance ratio was quantified by converting from the intensity of the distribution of absorption due to the carbonyl carbon of each amide bond and, if necessary, the methylene carbon adjacent to the carbonyl carbon. For example, in the case of 6T / 66, the ratio of adjacent 6T and 6T (corresponding to [XX] obs.) And the ratio of adjacent 6T and 66 (corresponding to [XY] obs.) Were measured. [X
In [X] calcd. And [XY] calcd., The chain distributions are statistically random, and the ratio of adjoining each other is calculated. From these values, the chain distribution existence ratio [XX] obs ./ [XX] calc
d. and [XY] obs ./ [XY] calcd. were calculated.

11) Evaluation of moldability Copolyamide pellets produced through the steps of primary condensation, melt extrusion and high degree of polymerization were vacuum dried at 100 ° C. for 16 hours and then fed to the hopper of an injection molding machine. The cylinder temperature was 10 ° C. higher than the melting point of the copolymerization, the mold temperature was 80 ° C., and a rectangular plate of 80 × 80 × 3 mm was molded under each condition of injection time / cooling time (= 5 seconds / 7 seconds). At this time, it was determined that a product having a normal square plate without deformation due to the ejection pin was good in moldability, and a product having deformation due to the ejection pin was defective.

Each embodiment will be described below. The reaction conditions and characteristics are shown in Tables 1 and 2, and the addition amount of monocarboxylic acid is shown therein. This amount means the amount (double mole) with respect to the number of moles of the monomer of the constituent component and the total number of moles of the dicarboxylic acid component unit and the diamine component unit of the salt.

Example 1 Hexamethylene ammonium adipate (66 salt), terephthalic acid, hexamethylene diamine, benzoic acid, ion-exchanged water and sodium hypophosphite were used in the composition and concentration shown in Table 1 in a screw and a tank. Is 1 to the radius of the tank
0.1% occupies 95% of the side surface below the liquid level at 3%
The mixture was charged into a 0 m ³ batch-type pressure polymerization tank, and after sufficiently purging with nitrogen, the temperature was raised to 140 ° C. and the pressure under stirring was 4.0 kg /
It was concentrated to a concentration of 85% by weight with cm ² (394.7692 kPa) -G. Subsequently, the temperature was raised to 290 ° C., which was the maximum temperature reached, under stirring for 1.5 hours, and the maximum polymerization pressure was 20 kg /
cm ² (1973.846 kPa) -G. The discharge was performed over 0.1 hour while supplying ion-exchanged water with a metering pump at a rate of 3 l / hr and maintaining the water vapor pressure at 20 kg / cm ² -G. The viscosity of this primary condensate was ηr = 1.6, and the melting point was 297 ° C.

The obtained primary condensate was heated at 100 ° C. for 24 hours.
After vacuum drying, the degree of polymerization was increased by an extruder. The extruder used was a 30 mmφ vent type twin-screw extruder (L / D = 4
5.5), rotating in the same direction, deep groove type. Further, the screw is composed of a forward full flight with L / D of 2 or less and a segment other than the forward full flight, the forward full flight portion is 78% of the whole, and the segment other than the forward full flight (L / D = 0.5 to 22% of the combination of the order kneading, the reverse kneading, the reverse full flight, and the seal ring), which was arranged at three positions immediately before the long vent, just before the short vent, and the melting zone. Vacuum time of -700 mmHg (-93.3254 kP) from long vent with residence time of 85 seconds and L / D = 5.
a), vacuum degree -7 from the short vent of L / D = 1.8
Degassed at 00 mmHg (-93.3254 kPa), melted to a high degree of polymerization at a screw rotation speed of 150 rpm and a maximum resin temperature of 325 ° C., and has a relative viscosity ηr = 2.5 and a melting point of 305.
A white pellet of ° C was obtained. The chain distribution abundance ratios of the structural units were respectively obtained by high resolution measurement of ¹³ C-NMR.
170.90ppm, 170.92ppm, 177.31ppm, 177.33ppm 4
When calculated from the peak ratio of the book, [XX] obs.
/ [XX] calcd. And [XY] obs ./ [XY] calcd.
Were 1.00 and 0.98, respectively. Table 1 shows the polymerization conditions, the chain distribution ratio of the copolyamide, the crystallization characteristics and the measurement results.

Example 2 Table 1 shows a salt of terephthalic acid and hexamethylenediamine, hexamethyleneammonium adipate (66 salt), a salt of isophthalic acid and hexamethylenediamine, sodium hypophosphite and ion-exchanged water. With the composition and concentration shown in, the distance between the screw and the tank is 2 to 4 of the tank radius.
0.1m occupies 90% of the side surface below the liquid level
^It was charged in the batch type pressure polymerization tank of No. 3 and sufficiently replaced with nitrogen, and then the temperature was raised to the maximum attainable temperature of 290 ° C. over 1.1 hours while stirring, and the maximum polymerization pressure was set to 20 kg / cm ² -G.
Discharge is 0.2 l / h of ion-exchanged water with a metering pump.
It was supplied at a rate of r and was carried out for 0.1 hour while maintaining the water vapor pressure at 20 kg / cm ² -G. The melting point of the obtained primary condensate was 302 ° C., and ηr was 1.4.

The obtained primary condensate was heated at 100 ° C. for 24 hours.
After vacuum drying, 20 mmφ vent type twin-screw extruder (L
The degree of polymerization was increased by using / D = 25). It is a co-rotating, deep groove type, and the screw is composed of screw segments with L / D of 2 or less. 78% of the forward full flight part of the whole, segments other than forward full flight (L / D
= 0.5-1 forward kneading, reverse kneading, orthogonal kneading, reverse full flight, seal ring, kneading needleal) is 22%, and it is arranged in two places just before the long vent and in the melting zone. What was done was used. A long vent with a residence time of 75 seconds and L / D = 5 was degassed at a vacuum degree of -700 mmHg, and the screw rotation speed was 15
At 0 rpm, maximum resin temperature of 320 ℃
White pellets having a relative viscosity ηr = 2.6 and a melting point of 305 ° C. were obtained. Table 1 shows the polymerization conditions, the chain distribution ratio of the copolyamide, the crystallization characteristics and the measurement results.

Example 3 Salt consisting of terephthalic acid and hexamethylenediamine, hexamethyleneammonium adipate (66 salt), ε-
Caprolactam, acetic acid, phosphoric acid and distilled water were charged at the composition and concentration shown in Table 1, and the maximum attainable temperature was 262 ° C. and the maximum polymerization pressure was 22 kg / cm ² -G (2 as in Example 2.
171.2306 kPa), water vapor pressure at discharge 22 kg /
The primary condensate was polymerized with the cm ² -G and the total time of polymerization and discharge being 1.3 hours.

The obtained primary condensate was heated at 100 ° C. for 24 hours.
After vacuum drying, the degree of polymerization was increased by an extruder. The extruder used was a 30 mmφ vent type twin-screw extruder (L / D = 4
5.5), rotating in the same direction, deep groove type. In addition, the screw is 60% of the segments other than forward full flight with L / D of 2 or less, and L / D
It consists of 40% of full forward flight with D exceeding 2 and includes segments other than normal full flight (forward kneading of L / D = 0.5 to 1, reverse kneading, orthogonal kneading, reverse full flight, seal ring). Combination) part is one of them
It was 5%, and it was used by being arranged at three positions immediately before the long vent, just before the short vent, and in the melting zone. With a residence time of 105 seconds, deaeration was performed from a long vent with L / D = 5 at a vacuum degree of −700 mmHg and from a short vent with L / D = 1.8 at a vacuum degree of −700 mmHg, with a screw rotation speed of 200 rpm and a maximum resin temperature of 325 ° C. The polymerization degree was increased by melting to obtain white pellets having a relative viscosity ηr = 2.5 and a melting point of 294 ° C. ^In the spectrum obtained by high-resolution measurement of ¹³ C-NMR, 39.94 ppm, 40.1
6 ppm, 40.58 ppm, 40.80 ppm, 17
0.21ppm, 170.90ppm, 170.92p
[XX] obs./ was calculated by converting from the peak ratios of the nine peaks of pm, 177.31 ppm, and 177.33 ppm.
[XX] calcd. And [XY] obs ./ [XY] calcd.
Were 1.06 and 0.94, respectively. Table 1 shows the polymerization conditions, the chain distribution ratio of the copolyamide, the crystallization characteristics and the measurement results.

Example 4 A batch of hexamethylene ammonium adipate (66 salt), a salt of terephthalic acid and hexamethylene diamine, benzoic acid and ion-exchanged water having a composition and concentration shown in Table 1 and a concentration of 0.1 m ³ was prepared. Example 1 was charged in a pressure polymerization tank and sodium hypophosphite was additionally added after the formation of the primary condensate.
The primary condensation product was polymerized and the degree of polymerization was increased in the same manner as in.
Table 1 shows the polymerization conditions, the chain distribution ratio of the copolyamide, the crystallization characteristics and the measurement results.

Example 5 Using hexamethylene ammonium adipate (66 salt), a salt of terephthalic acid and hexamethylene diamine as a raw material, and using a batch type pressure polymerization tank of 0.1 m ³ , the same as in Example 1 The primary condensate was polymerized. Polymerization was possible for a total polymerization time of 4 hours, and the primary condensate could be discharged well. Further, the degree of polymerization was increased in the same manner as in Example 1. Table 1 shows the polymerization conditions, the chain distribution ratio of the copolyamide, the crystallization characteristics and the measurement results.

Example 6 Salt of terephthalic acid and dodecamethylenediamine (1
2T) (shown in Table 1) and a salt of adipic acid and dodecamethylenediamine (126 and shown in Table 1) were used as raw materials, and the primary condensate was polymerized in the same manner as in Example 1.

The obtained primary condensate was heated at 100 ° C. for 24 hours.
After vacuum drying, 20 mmφ vent type twin-screw extruder (L
The degree of polymerization was increased by using / D = 25). It is a co-rotating, deep groove type, and the screw is composed of screw segments with L / D of 2 or less. 78% of the forward full flight part of the whole, segments other than forward full flight (L / D
= 0.5 to 1 forward kneading, reverse kneading, orthogonal kneading, reverse full flight, seal ring, kneading needleal) was 22%, and those arranged in three places were used. Table 1 shows the polymerization conditions, the chain distribution ratio of the copolyamide, the crystallization characteristics and the measurement results.

Example 7 Using the salt of terephthalic acid and dodecamethylenediamine and the salt of adipic acid and dodecamethylenediamine as raw materials, the primary condensate was polymerized and the degree of polymerization was increased in the same manner as in Example 1. Table 2 shows the polymerization conditions, the chain distribution ratio of the copolyamide, the crystallization characteristics and the measurement results.

Example 8 The primary condensate was polymerized according to the method of Example 1 without using a phosphorus-based catalyst, and the polymerization degree was increased by using the same vent type twin-screw extruder as in Example 1. Table 2 shows the polymerization conditions, the chain distribution ratio of the copolyamide, the crystallization characteristics and the measurement results.

According to the methods of Examples 1 to 8, the primary condensates could be satisfactorily polymerized, the chain distribution of the polymer after increasing the degree of polymerization supported a random structure, and the half crystallization time was also an appropriate value. The moldability was good, and a polyamide having excellent color tone, tensile strength, tensile elongation, bending strength, bending elastic modulus, chemical resistance, and heat distortion temperature was obtained.

Comparative Example 1 The same preparation as in Example 1 was carried out, and the maximum temperature reached was 245.
The temperature was set to 0 ° C and the primary condensate was polymerized in the same manner as in Example 1 except for the above. The melting point of the obtained primary condensate was 286 ° C., and ηr was 1.14.

The obtained primary condensate was heated at 100 ° C. for 24 hours.
After vacuum drying, the residence time was lengthened to 210 seconds under the same conditions as in Example 1 so that the relative viscosity was 2.5, and the polymerization degree was increased. Table 2 shows the polymerization conditions, the chain distribution ratio of the copolyamide, the crystallization characteristics and the measurement results.

Comparative Example 2 The same preparation as in Example 1 was carried out, and the maximum ultimate pressure was 50 k.
The primary condensate was polymerized in the same manner as in Example 1 except that g / cm ² -G was used. The melting point of the obtained primary condensate is 28.
At 5 ° C., ηr was a primary condensate of 1.14.

The obtained primary condensate was heated at 100 ° C. for 24 hours.
After vacuum drying, the residence time was lengthened to 210 seconds under the same conditions as in Example 1 so that the relative viscosity was 2.5, and the polymerization degree was increased. Table 2 shows the polymerization conditions, the chain distribution ratio of the copolyamide, the crystallization characteristics and the measurement results.

Comparative Example 3 The same charging as in Example 1 was performed, and the maximum temperature reached was 335.
The temperature was set to 0 ° C and the primary condensate was polymerized in the same manner as in Example 1 except for the above. Precipitation solidified in the polymerization tank and discharge was not possible.

Comparative Example 4 The same primary condensate as in Example 1 was vacuum dried at 100 ° C. for 24 hours, and then a 20 mmφ vent type single-screw extruder was used. Polymerization was performed. Residence time 250 seconds, L / D
= Vapor pressure of -700 mmHg from short vent of 1.8
Was degassed, and the degree of polymerization was increased at a screw rotation speed of 150 rpm and a maximum resin temperature of 325 ° C. Table 2 shows the polymerization conditions, the chain distribution ratio of the copolyamide, the crystallization characteristics and the measurement results.

Comparative Example 1 is a production condition in which the maximum reached temperature during the polymerization of the primary condensate is low, and Comparative Example 2 is a condition in which the maximum reached pressure during the polymerization of the primary condensate is high, and the degree of polymerization of the primary condensate is sufficient. However, the chain distribution of the polymer after increasing the polymerization degree deviated from the theoretical random structure. As a result, the moldability was poor and the color tone and mechanical properties were poor.
In Comparative Example 3, the highest temperature reached during the polymerization of the primary condensate was high, so the primary condensate could not be discharged. In Comparative Example 4, the half crystallization time was extremely long because the polymerization degree was not efficiently increased by using the specific screw segment when the polymerization degree was increased. As a result, the moldability was extremely poor and the polymer physical properties were inferior.

[0076]

[Table 1]

[0077]

[Table 2]

[0078]

EFFECT OF THE INVENTION The copolymerized polyamide having the chain distribution and crystallization characteristics of the present invention has excellent moldability, color tone, tensile strength, tensile elongation, flexural strength, flexural modulus, chemical resistance, heat distortion temperature and the like. An improved one is obtained.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-5-230204 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) C08G 69/00-69/50

Claims (24)

(57) [Claims] 1. An amide bond formed from an aliphatic diamine having 4 to 14 carbon atoms and terephthalic acid, and the chain distribution abundance ratio of the amide bond satisfies the formulas (A) and (B),
Further, a copolyamide having a semi-crystallization time that satisfies the formula (C). 0.9 ≦ [XY] obs ./ [XY] calcd. ≦ 1.1 (A) 0.9 ≦ [XX] obs ./ [XX] calcd. ≦ 1.1 (B) [where X is It is an amide bond formed from an aliphatic diamine having 4 to 14 carbon atoms and terephthalic acid, and Y means an amide bond other than X. [XY] is the proportion of all amide bonds where X and Y are adjacent to each other in the polymer structure, and [XX] is the proportion of all amide bonds where X and X are adjacent to each other in the polymer structure. Indicates a percentage. [XY] calcd. And [XX] calcd. Are the respective values of [XY] and [XX] in which the amide bonds of X and Y are calculated as a statistically random linkage distribution, and [XY] obs. And [XX] obs. Is measured from the copolyamide [X]
It is each value of Y] and [XX]. ] 4.4-0.1 (Tm-T) ≤ logt _1/2 ≤ 5.5-0.1 (Tm-T) (C) [where t _1/2 is a half-crystallization time (seconds), and Tm is a copolyamide. Is the melting point (° C.), and T is the temperature (° C.) at which the half crystallization time is measured. ] 2. The melting point of the copolyamide is 260 to 32.
The copolyamide according to claim 1, which is at 0 ° C. 3. The temperature T for measuring the half-crystallization time is lower than the melting point of the copolyamide by 35 ° C.
The copolyamide according to claim 1 or 2, wherein the temperature is in the range of 5 ° C lower. 4. The copolymerized polyamide according to claim 1, wherein the temperature T for measuring the half-crystallization time is 30 ° C. lower than the melting point of the copolymerized polyamide. 5. The copolyamide according to claim 1, wherein the aliphatic diamine has 6 carbon atoms. 6. The copolymerized polyamide has a structural unit (I): And at least one structural unit selected from structural units (II) to (IV): [Chemical 3] [Chemical 4] The copolyamide according to any one of claims 1 to 5, which has a structural unit consisting of: 7. The structural units (I) and (II) account for 50% by weight or more of the entire copolymer composition, and the weight ratio of (I) / (II) is in the range of 80/20 to 20/80. The copolymerized polyamide according to claim 6, characterized in that 8. The chain distribution abundance ratios represented by the formulas (D) and (E).
The copolymerized polyamide according to any one of claims 1 to 7, wherein 0.95 ≦ [XY] obs ./ [XY] calcd. ≦ 1.05 (D) 0.95 ≦ [XX] obs ./ [XX] calcd. ≦ 1.05 (E) 9. The copolymerized polyamide according to claim 1, wherein the half-crystallization time satisfies the formula (F). 4.6-0.1 (Tm-T) ≤ logt _1/2 ≤ 5.3-0.1 (Tm-T) (F) 10. The highest ultimate pressure is 5 kg / cm ² -G or more and less than 23 kg / cm ² -G, and the highest ultimate temperature is 2.
After forming the primary condensate under the conditions of more than 60 ° C. and 330 ° C. or less, using a twin screw extruder including a screw segment in which {screw length L} / {outermost diameter D of screw} is 2 or less. And having an amide bond formed from an aliphatic diamine having 4 to 14 carbon atoms and terephthalic acid, characterized in that it has a high degree of polymerization by melt extrusion, and the chain distribution abundance ratio of the amide bond is represented by formula (A) and Satisfies (B),
Furthermore, the method for producing a copolyamide having a semi-crystallization time that satisfies the formula (C). 0.9 ≦ [XY] obs ./ [XY] calcd. ≦ 1.1 (A) 0.9 ≦ [XX] obs ./ [XX] calcd. ≦ 1.1 (B) [where X is It is an amide bond formed from an aliphatic diamine having 4 to 14 carbon atoms and terephthalic acid, and Y means an amide bond other than X. [XY] is the proportion of X and Y adjacent to each other in the polymer structure, and [XX] is the proportion of X and X adjacent to the total polyamide number in the polymer structure. [XY] calcd. And [XX] calcd. Are the respective values of [XY] and [XX] in which the amide bonds of X and Y are calculated as a statistically random linkage distribution, and [XY] obs. And [XX] obs. Is measured from the copolyamide [X]
It is each value of Y] and [XX]. ] 4.4-0.1 (Tm-T) ≤ logt _1/2 ≤ 5.5-0.1 (Tm-T) (C) [where t _1/2 is a half crystallization time (seconds) and Tm is a copolyamide. Is the melting point (° C.), and T is the measurement temperature (° C.) of the half-crystallization time. ] 11. The semi-crystallization time measurement temperature T is in the range of 35 ° C. below the melting point of the copolyamide to 25 ° C. below the melting point of the copolyamide.
0. The method for producing a copolyamide according to 0. 12. The method for producing a copolyamide according to claim 10, wherein the temperature T for measuring the half-crystallization time is 30 ° C. lower than the melting point of the copolyamide. 13. The method of increasing the degree of polymerization by melt extrusion using a twin-screw extruder is a condition that satisfies the relationship of the formula (G) while performing vacuum deaeration.
2. The method for producing a copolyamide according to any one of 2 above. t ≦ 5000 × Δηr / (T R -280) (G) (t: retention time (in seconds), Δηr: variation in relative viscosity due to high degree of polymerization of the copolymer polyamide, T _R: at the time of high degree of polymerization Maximum temperature of resin (℃)) 14. The copolymerized polyamide according to claim 10, wherein the relative viscosity of the primary condensate supplied to the twin-screw extruder is 1.15 to 2.5. Method. 15. A twin-screw extruder comprising a screw segment having an L / D of 2 or less in a length of 5 to 100.
% Is included, The claim 10 characterized by the above-mentioned.
14. The method for producing a copolyamide according to any one of 14. 16. The method for producing a copolyamide according to claim 10, wherein the screw segment having an L / D of 2 or less contains a segment other than forward full flight. 17. The melting point of the copolyamide is 260 to 32.
It is 0 degreeC, The manufacturing method of the copolyamide in any one of Claims 10-16 characterized by the above-mentioned. 18. The method for producing a copolyamide according to claim 10, wherein the aliphatic diamine has 6 carbon atoms. 19. A copolymerized polyamide having a structural unit (I): And at least one type of structural unit selected from (II) to (IV): [Chemical 7] [Chemical 8] The method for producing a copolyamide according to any one of claims 10 to 19, which comprises a structural unit comprising 20. The sum of structural units (I) and (II) is 50% by weight or more of the entire copolymer composition, and the weight ratio of structural units is (I) / (II) = 80 to 20/20 to 80. 20. The method for producing the copolyamide according to claim 19, wherein 21. The method for producing the copolyamide according to claim 10, wherein the chain distribution abundance ratio satisfies the formulas (D) and (E). 0.95 ≦ [XY] obs ./ [XY] calcd. ≦ 1.05 (D) 0.95 ≦ [XX] obs ./ [XX] calcd. ≦ 1.05 (E) 22. The method for producing the copolyamide according to claim 10, wherein the half-crystallization time satisfies the formula (F). 4.6-0.1 (Tm-T) ≤ logt _1/2 ≤ 5.3-0.1 (Tm-T) (F) 23. The maximum ultimate pressure when forming the primary condensate is 10.
The method for producing a copolyamide according to any one of claims 10 to 22, wherein the content is not less than kg / cm ² -G and not more than 20 kg / cm ² -G. 24. The melting point of the copolyamide is 280 to 32.
11. The temperature is 0 ° C., and the highest temperature reached during the polymerization of the primary condensate is above the melting point of polyamide minus 20 ° C. and below the melting point of polyamide plus 10 ° C. 10.
23. The method for producing the copolyamide according to any one of 23.