JP3601384B2 - Novel polyamide and process for producing the same - Google Patents

Description

＊１：デヒドロアビエチン酸、ジデヒドロアビエチン酸、テトラデヒドロアビエチン酸の混合物（荒川化学製、ＫＲ−６１０）
【００２９】
【発明の効果】
末端基が少なくとも２個以上の芳香族環および／または脂環族環を含有する構造であって、脂肪族ジアミンと脂肪族ジカルボン酸、脂肪族ジアミンと芳香族ジカルボン酸、芳香族ジアミンと脂肪族ジカルボン酸、ω−アミノカルボン酸、ラクタム、及びこれらの２種類以上の組合せのいずれかのモノマーのみから合成されてなるポリアミドは、結晶化速度が遅く、押出成形やブロー成形などに好適なポリアミドである。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a novel polyamide having a specific end group structure and a method for producing the same. Specifically, the present invention relates to a novel polyamide having a structure in which the terminal group contains at least two aromatic rings and / or alicyclic rings, and a method for producing the same. This new polyamide has a low crystallization speed and is excellent in molding processability such as extrusion molding and blow molding, and is used for automotive parts, packaging materials, electrical and electronic materials, and the like.
[0002]
[Prior art]
Conventionally, there is no specific report regarding a polyamide having at least two aromatic rings and / or alicyclic rings as a terminal group structure.
Polyamides are excellent in mechanical properties and thermal properties. In particular, crystalline polyamides are used in various industrial fields because they have good heat resistance due to the presence of crystals. It is known that the crystallinity and the crystallization speed related to this crystal have a great influence on the physical properties and moldability of polyamide. For this reason, many studies have been made on techniques for controlling the crystallinity and crystallization speed of polyamide. For example, a method using various crystal nucleating agents has been proposed for accelerating the crystallization rate of polyamide. These crystal nucleating agents are effective for improving productivity in the injection molding method. On the other hand, there are not many proposals regarding a method for delaying the crystallization rate. For example, as a method of delaying the crystallization rate of polyamide, a method of copolymerizing different types of polyamides has been proposed. This method usually reduces the melting point and crystallinity of the polyamide, and there are restrictions on the applications in which this method can be used. Japanese Patent Application Laid-Open No. 62-246958 discloses a method for reducing the crystallization rate of polyamide by adding an azine compound. However, the azine compound is a compound used as a dye, and when this is used, the polyamide is colored in a specific color, so that there is a restriction in terms of application. When the crystallization rate is slow, polyamides having a slow crystallization rate have been demanded because of great advantages in molding such as the stretching process in extrusion molding and the easy shaping in blow molding.
[Problems to be solved by the invention]
An object of the present invention is to provide a polyamide having a low crystallization rate and a production method thereof with few problems in the prior art such as a melting point and mechanical properties are lowered, and the polyamide is colored.
[Means for Solving the Problems]
As a result of examining the above problems, the present inventors have found that a polyamide having a structure in which the terminal group contains at least two aromatic rings and / or alicyclic rings has a low crystallization rate. The invention has been reached.
[0003]
That is, the first invention of the present invention is a structure in which the terminal group contains at least two aromatic rings and / or alicyclic rings,
Aliphatic diamines and aliphatic dicarboxylic acids,
Aliphatic diamines and aromatic dicarboxylic acids,
Aromatic diamines and aliphatic dicarboxylic acids,
ω-aminocarboxylic acid,
Lactam,
And a novel polyamide characterized in that it is synthesized only from any monomer of a combination of two or more of these.
[0004]
In the second invention of the present invention, at least the terminal group for synthesizing a polyamide in the presence of a monocarboxylic acid and / or a monoamine containing at least two aromatic rings and / or alicyclic rings. A structure containing two or more aromatic rings and / or alicyclic rings,
Aliphatic diamines and aliphatic dicarboxylic acids,
Aliphatic diamines and aromatic dicarboxylic acids,
Aromatic diamines and aliphatic dicarboxylic acids,
ω-aminocarboxylic acid,
Lactam,
And a process for producing a novel polyamide, which is synthesized only from any one monomer of a combination of two or more of these.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail.
The polyamide of the present invention is a polyamide having a structure containing at least two aromatic rings and / or alicyclic rings in the terminal group. Examples of the aromatic ring include a benzene ring, a naphthalene ring, an anthracene ring, and a ring of these derivatives. Examples of the alicyclic ring include a cycloparaffin ring, a cycloolefin ring, a terpene ring, a steroid ring, and a ring of these derivatives. Is mentioned.
[0006]
The main chain of this polyamide is composed of a crystalline polyamide composed of aliphatic or aliphatic and aromatic, and has a number average molecular weight of 3,000 to 60,000, preferably 4,000 to 50,000, more preferably Is a polyamide of 5,000 to 45,000. When the number average molecular weight is larger than 60,000, the effect of the end group structure is hardly recognized, and the crystallization speed may not be so slow. On the other hand, if it is less than 3,000, the excellent properties inherent in polyamide cannot be obtained, which is not preferable.
[0007]
The polyamide is an aliphatic diamine and an aliphatic dicarboxylic acid, an aliphatic diamine and an aromatic dicarboxylic acid, an aromatic diamine and an aliphatic dicarboxylic acid, an ω-aminocarboxylic acid, a lactam, or a combination of two or more of these. It is synthesized from only the monomer.
The diamine is usually a diamine having 2 to 24 carbon atoms, and specific examples include ethylene diamine, trimethylene diamine, tetramethylene diamine, pentamethylene diamine, hexamethylene diamine, heptamethylene diamine, octamethylene diamine, nona. Of methylenediamine, decamethylenediamine, undecamethylenediamine, dodecamethylenediamine, tridecamethylenediamine, hexadecamethylenediamine, octadecamethylenediamine, 2,2,4 (or 2,4,4) -trimethylhexamethylenediamine Such as aliphatic diamine, cyclohexanediamine, methylcyclohexanediamine, alicyclic diamine such as bis- (4,4′-aminocyclohexyl) methane, aromatic diamine such as xylylenediamine, and the like. Can be mentioned.
[0008]
As the dicarboxylic acid, a dicarboxylic acid having 2 to 24 carbon atoms is usually used. Specific examples include malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedione. Acid, dodecanedioic acid, tridecadionic acid, tetradecadionic acid, hexadecadionic acid, hexadecenedionic acid, octadecadionic acid, octadecenedionic acid, eicosandioic acid, eicosendioic acid, eicosadienedioic acid, docosandione Acids, aliphatic dicarboxylic acids such as 2,2,4-trimethyladipic acid, alicyclic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid, phthalic acid, xylylene dicarboxylic acid And aromatic dicarboxylic acids.
These diamines and dicarboxylic acids are used in an equimolar proportion.
[0009]
Specific examples of ω-aminocarboxylic acid include 5-aminovaleric acid, 6-aminocaproic acid, 7-aminoheptanoic acid, 8-aminooctanoic acid, 9-aminononanoic acid, 10-aminocapric acid, and 11-aminoundecanoic acid. , 12-aminododecanoic acid and the like. Specific examples of the lactam include pyrrolidone, methyl pyrrolidone, caprolactam, enantolactam, undecane lactam, dodecalactam and the like.
These diamine and dicarboxylic acid blends, ω-aminocarboxylic acids, lactams, and the like may be used alone, or two or more of these may be used in appropriate combination.
[0010]
The polyamide having a structure in which the terminal group of the present invention contains at least two or more aromatic rings and / or alicyclic rings is a monocarboxylic acid containing at least two or more aromatic rings and / or alicyclic rings. By synthesizing a polyamide by a known method such as melt polymerization, solution polymerization, solid phase polymerization of a mixture of the above-mentioned diamine and dicarboxylic acid or ω-aminocarboxylic acid or lactam in the presence of an acid and / or monoamine. Can be manufactured. For example, in the presence of a monocarboxylic acid and / or monoamine containing at least two aromatic rings and / or alicyclic rings, the above-mentioned dicarboxylic acid and diamine are mixed in equimolar amounts, or ω-amino If necessary, it can be produced by a method of polycondensation by heating with a small amount of water, or a method of ring-opening polymerization by heating a lactam with a small amount of water. At this time, the amount of the monocarboxylic acid and / or monoamine containing at least two aromatic rings and / or alicyclic rings is appropriately determined depending on the molecular weight of the polyamide to be synthesized.
[0011]
In this invention, the reaction temperature which synthesize | combines polyamide is the range of 140 to 350 degreeC, Preferably, it is 150 to 340 degreeC. When the reaction temperature is lower than 140 ° C., the reaction rate becomes slow and it takes a long time to obtain polyamide. On the other hand, if the reaction temperature is higher than 350 ° C., side reactions such as coloring and crosslinking occur, which is not preferable. In the synthesis of polyamide, additives such as a phosphorus catalyst and an antioxidant can be used for promoting the reaction and preventing deterioration.
[0012]
In the monocarboxylic acid containing at least two or more aromatic rings and / or alicyclic rings used in the present invention, at least two aromatic rings and / or alicyclic rings are directly bonded to each other. A monocarboxylic acid having a structure or a structure having 5 or less atoms between aromatic rings and / or alicyclic rings. Moreover, it is preferable that it is the monocarboxylic acid which does not contain the functional group which influences the synthesis | combination of polyamide other than one carboxyl group. As atoms within 5 atoms existing between aromatic rings and / or alicyclic rings, CR ₂ (where R is hydrogen, an alkyl group having 1 to 4 carbon atoms), O, CO, SiR ₂ (where R is hydrogen, an alkyl group having 1 to 4 carbon atoms), SiO and the like. Specific examples of functional groups that affect the synthesis of polyamide include a carboxyl group, an amino group, a hydroxyl group, and a vinyl group.
[0013]
Specific examples of such monocarboxylic acids include dicyclohexylacetic acid, diphenylacetic acid, diphenylpropionic acid, biphenylacetic acid, 9-fluoreneacetic acid, 9-fluorenecarboxylic acid, naphthylacetic acid, naphthoxyacetic acid, 1-pyreneacetic acid, 1-pyrenebutyric acid, Triphenylacetic acid, 3,3,3-triphenylpropionic acid, 4,4′-bis (p-hydroxyphenyl) pentanoic acid, biphenylcarboxylic acid, 4-methyl-2-biphenylcarboxylic acid, 9-anthracenecarboxylic acid, 2-phenethylbenzoic acid, benzoylbenzoic acid, phenoxybenzoic acid, naphthoic acid, fluorenecarboxylic acid, quinolinecarboxylic acid, 2,2′-biphenyldicarboxylic acid and its acid anhydride, 1,8-naphthalic acid anhydride, etc. Abietic acid, dihydroabieticin , Mention may be made of rosin acids such as tetrahydroabietic acid, deoxycholic acid, calls acids such as cholic acid.
[0014]
The monoamine containing at least two or more aromatic rings and / or alicyclic rings used in the present invention has a structure in which at least two aromatic rings and / or alicyclic rings are directly bonded to each other, Alternatively, it is a monoamine having a structure in which no more than 5 atoms are present between aromatic rings and / or alicyclic rings. Further, a monoamine in which an amino group is directly bonded to an aliphatic group or does not contain a functional group that affects the synthesis of polyamide other than one amino group is preferable. As atoms within 5 atoms existing between aromatic rings and / or alicyclic rings, CR ₂ (where R is hydrogen, an alkyl group having 1 to 4 carbon atoms), O, CO, SiR ₂ (where R is hydrogen, an alkyl group having 1 to 4 carbon atoms), SiO and the like. Specific examples of functional groups that affect the synthesis of polyamide include a carboxyl group, an amino group, a hydroxyl group, and a vinyl group.
[0015]
Specific examples of such monoamines include dicyclohexylamine, dibenzylamine, aminodiphenylmethane, diphenylethylamine, diphenylpropylamine, naphthalenemethylamine, 1- (1-naphthyl) ethylamine, 1-pyrenemethylamine, dehydroabiethylamine, and the like. Can be mentioned.
[0016]
If there is one aromatic ring and / or alicyclic ring, or there are two or more aromatic rings and / or alicyclic rings, and there are 6 or more atoms between them, crystallization occurs. The effect of slowing the speed is reduced.
In addition, the monocarboxylic acid or monoamine containing at least two aromatic rings and / or alicyclic rings has one carboxyl group or one amino group. If there is an influencing functional group, the synthesis of polyamide may be inhibited, which is not preferable.
[0017]
The aforementioned monocarboxylic acid and / or monoamine containing at least two aromatic rings and / or alicyclic rings may be used alone, and some of the above monocarboxylic acids and monoamines may be used. You may use it in combination.
[0018]
The polyamide of the present invention may contain a reinforcing material, a filler, an antioxidant, an ultraviolet absorber, a stabilizer, a pigment, a lubricant, a flame retardant, or other additives.
[0019]
【Example】
Hereinafter, the present invention will be described in more detail with reference to examples. In addition, the characteristic evaluation described in the Example was performed with the following method.
[0020]
(1) Measurement of solution viscosity of polyamide The solution viscosity ηr was determined by the equation (1) by measuring with a Ubbelohde viscometer at a concentration of 1.0 g / 100 ml using 97% sulfuric acid as a solvent at 25 ° C.
[Expression 1]
ηr = t / t ₀ (1)
Where t; solution outflow time (seconds), t ₀ ; solvent only outflow time (seconds)
[0021]
(2) Measurement of end group concentration Amino group concentration;
The sample was dissolved in 40 ml of a phenol / methanol (4/1; volume ratio) mixed solvent, and several drops of thymol blue were added as an indicator, followed by titration with 1/20 N hydrochloric acid at room temperature. The amino group concentration [NH ₂ ] (unit: mol / g) was calculated by the formula (2).
[Expression 2]
[NH ₂ ] = (L ₁ −L ₂ ) × f ₁ × 10 ⁻⁴ / (2 × S ₁ ) (2)
Here, L ₁ ; titration volume of sample solution (ml), L ₂ ; titration volume of solvent only (ml), f ₁ ; factor of 1 / 20N hydrochloric acid, S ₁ ; sample volume (g)
Carboxyl group concentration;
A sample was dissolved in 40 ml of benzyl alcohol at 180 ° C., several drops of phenolphthalein were added as an indicator, and titrated with ethanolic 1 / 20N potassium hydroxide. The carboxyl group concentration [COOH] (unit: mol / g) was calculated by the formula (3).
[Equation 3]
[COOH] = (L ₃ −L ₄ ) × f ₂ × 10 ⁻⁴ / (2 × S ₂ ) (3)
Here, L ₃ ; titration amount of sample solution (ml), L ₄ ; titration amount of solvent only (ml), f ₂ ; factor of 1/20 N potassium hydroxide, S ₂ ; sample amount (g)
(3) Measurement of crystallization temperature, melting point and half crystallization time The crystallization temperature, melting point and half crystallization time were measured using DSC-7 manufactured by Perkin Elmer.
The measurement sample was held at 280 ° C. for 10 minutes, and then cooled at a rate of 20 ° C./min. The peak temperature of the crystallization temperature curve obtained was used as the crystallization temperature. Moreover, the peak temperature of the melting temperature curve when it heated up at 20 degrees C / min after cooling to -40 degreeC was made into melting | fusing point.
The semi-crystallization time is determined by holding the measurement sample at 260 ° C. for 10 minutes, rapidly cooling to 200 ° C. at 500 ° C./min, holding at 200 ° C., measuring the exothermic peak due to crystallization, The time when the heat quantity of 1/2 was reached was taken.
[0022]
(4) Measurement of ¹ H-NMR
¹ H-NMR was measured at room temperature using JEOL JNM-EX400WB FT-NMR (manufactured by JEOL Ltd.), using D ₂ SO ₄ (97%) as a solvent and tetramethylsilane as an internal standard.
[0023]
Example 1
226.3 g of ε-caprolactam, 10 g of distilled water and 3.6 g of triphenylacetic acid were charged into a 1 liter autoclave, and after substitution with nitrogen, polymerization was performed while stirring at 230 ° C. and 12 atm for 3 hours. Next, the temperature was raised while releasing the pressure, and polymerization was performed while stirring at 250 ° C. for 3 hours. The obtained polyamide 6 was pulverized and then subjected to Soxhlet extraction with methanol for 24 hours to remove unreacted monomers and dried to obtain white polyamide 6. The polyamide 6 had a solution viscosity ηr of 2.36. The carboxyl end group concentration was 6.3 × 10 ⁻⁵ mol / g, the amino end group concentration was 0.9 × 10 ⁻⁵ mol / g, and the number average molecular weight was about 21,700. A signal based on a benzene ring was observed at 7-8 ppm in a very low amino end group concentration and ¹ H-NMR spectrum. This indicates that a triphenyl group structure is introduced into the terminal group. The polyamide 6 having the triphenyl end group structure had a crystallization temperature of 179 ° C. and a melting point of 223 ° C. The half crystallization time at 200 ° C. was 144 seconds.
[0024]
Example 2 to Example 7
Polyamide 6 having various terminal group structures was synthesized in the same manner as in Example 1 except that the monocarboxylic acid or monoamine shown in Table 1 was used in an amount of 1/150 molar equivalent to ε-caprolactam. The analysis results are shown in Table 1.
[0025]
Example 8
The same procedure as in Example 1 was carried out except that aminodiphenylmethane and diphenylacetic acid were each used in an amount of 1/150 molar equivalent to ε-caprolactam, to synthesize polyamide 6 containing two aromatic rings at both terminal groups. . The analysis results are shown in Table 1.
[0026]
Comparative Example 1
Polyamide 6 was synthesized in the same manner as in Example 1 except that stearic acid was used in an amount of 1/150 molar equivalent to ε-caprolactam. The analysis results are shown in Table 1. The half crystallization time of this polyamide 6 was 107 seconds.
[0027]
Comparative Example 2
Polyamide 6 was synthesized in the same manner as in Example 1 except that 1/150 molar equivalent of benzylamine was used with respect to ε-caprolactam. The analysis results are shown in Table 1.
[0028]
[Table 1]

* 1: A mixture of dehydroabietic acid, didehydroabietic acid, and tetradehydroabietic acid (Arakawa Chemicals, KR-610)
[0029]
【The invention's effect】
The terminal group has a structure containing at least two aromatic rings and / or alicyclic rings, and includes aliphatic diamine and aliphatic dicarboxylic acid, aliphatic diamine and aromatic dicarboxylic acid, aromatic diamine and aliphatic Polyamides synthesized from only dicarboxylic acids, ω-aminocarboxylic acids, lactams, and monomers of any combination of two or more thereof have low crystallization speeds and are suitable for extrusion molding, blow molding and the like. is there.

Claims (3)

The terminal group contains at least two aromatic rings and / or alicyclic rings ,
Aliphatic diamines and aliphatic dicarboxylic acids,
Aliphatic diamines and aromatic dicarboxylic acids,
Aromatic diamines and aliphatic dicarboxylic acids,
ω-aminocarboxylic acid,
Lactam,
And combinations of two or more of these
A novel polyamide synthesized from only one of the monomers . The method for producing a novel polyamide according to claim 1, wherein the polyamide is synthesized in the presence of a monocarboxylic acid and / or a monoamine containing at least two aromatic rings and / or alicyclic rings. A structure in which at least two aromatic rings and / or alicyclic rings are directly bonded to each other, or a structure in which no more than 5 atoms are present between aromatic rings and / or alicyclic rings The method for producing a novel polyamide according to claim 1, wherein the polyamide is synthesized in the presence of a monocarboxylic acid and / or a monoamine.