JPH09295961A - Production of aromatic ester amide - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily produce an aromatic ester amide having high purity and reactivity from an aminobenzoic acid alkyl ester and terephthaloyl dichloride at a low cost without necessitating purification steps such as recrystallization and crystallization. SOLUTION: An aromatic ester amide of formula II is produced by reacting an aminobenzoic acid alkyl ester of formula 1 (R is a 1-10C alkyl) with terephthaloyl dichloride in an amide solvent and adding a basic inorganic compound having a water-solubility of >=10wt.% to the reaction product. The amide solvent is e.g. N,N-dimethylacetamide or N,N-dimethylf ormamide. The basic inorganic compound is e.g. ammonia water or an aqueous solution of ammonium acetate, lithium acetate, etc. The purification of the product comprises the washing with water, hot water or their combination. The compound of formula II can be used as a hard segment of a block copolymer-type thermoplastic elastomer.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a highly pure and highly reactive aromatic ester amide. The aromatic ester amide obtained in the present invention can be used as a hard segment of a block copolymer type thermoplastic elastomer.

[0002]

2. Description of the Related Art Conventionally, amide type thermoplastic elastomers (hereinafter abbreviated as amide type TPE) are excellent in oil resistance and mechanical properties and have been used for automobile parts, electric / electronic parts, mechanical parts and the like. These hard segments are 6
Aliphatic aminocarboxylic acids such as nylon and 6,6 nylon are commonly used.

However, the amide-based TPE using an aliphatic aminocarboxylic acid as a hard segment and polytetramethylene glycol or polycaprolactone as a soft segment does not have sufficient heat resistance.

As a hard segment of a high heat resistant amide type TPE, diamide dicarboxylic acid diester (Japanese Patent Publication No.
4-30751) and dibutyl diamide dicarboxylate (Japanese Patent Laid-Open No. 63-159432). However, these utilize transesterification reaction to synthesize the polymer by polycondensation reaction with debutyl alcohol. However, the diffusion speed of butyl alcohol is slow and the reactivity with soft segment is low, so high molecular weight amide TPE Is not obtained and the mechanical properties are inferior.

Generally, when an aromatic amide compound is produced, for example, in JP-A-58-194854,
Terephthalic acid prepared by dissolving anthranilic acid in an aqueous sodium carbonate solution and dissolving it in an organic solvent (only aromatic hydrocarbons, ketones, ethers, and halogenated hydrocarbons are disclosed as examples). After dichloride was added dropwise and stirred, the reaction system was acidified to precipitate the product, which was filtered to produce an aromatic amide compound.

When an aromatic ester amide is synthesized by this method, it is difficult to obtain a high-purity product,
Further, because of poor crystallinity, purification such as recrystallization and crystallization becomes necessary.

When an aromatic ester amide is used as a monomer for a polycondensation polymer, it is necessary that the monomer has a high purity, and it is difficult to obtain a sufficient purity as a monomer by the conventional method, and a high molecular weight polymer is obtained. Is difficult, and it requires costly purification such as recrystallization and crystallization.

[0008]

An object of the present invention is to provide a method for producing a highly pure and highly reactive aromatic ester amide simply and at low cost without requiring purification such as recrystallization and crystallization. Especially.

[0009]

Means for Solving the Problems As a result of intensive studies to achieve the above-mentioned object, the inventors of the present invention have reacted an aminobenzoic acid alkyl ester with terephthalic acid dichloride in an amide solvent, and then reacted with a basic compound. By adding an inorganic compound, a method for producing a highly pure and highly reactive aromatic ester amide was found, and the present invention was completed.

That is, the present invention provides the following general formula (1)

[0011]

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An aminobenzoic acid alkyl ester represented by the formula (wherein R represents an alkyl group having 1 to 10 carbon atoms) and terephthalic acid dichloride are reacted in an amide solvent, and then the solubility in water is 10 wt% or more. The following general formula (2) is characterized by adding a basic inorganic compound

[0013]

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A method for producing an aromatic ester amide represented by the formula (wherein R represents an alkyl group having 1 to 10 carbon atoms).

Hereinafter, the present invention will be described in detail.

Examples of the aminobenzoic acid alkyl ester in the present invention include methyl, ethyl, propyl and butyl esters of aminobenzoic acids such as 4-aminobenzoic acid and 3-aminobenzoic acid. Preferably 4-
Methyl aminobenzoate or ethyl 4-aminobenzoate is used.

The amide-based solvent is, for example,
N, N-dimethylacetamide, N, N-dimethylformamide, N-methylformamide, N-methylacetamide, formamide, acetamide, N-methyl-2
-Pyrrolidone, N, N-dimethylpropionamide,
Examples include N, N-diethylpropionic acid amide, tetramethylphosphortriamide, N-methylcaprolactam and the like.

Of these, N-methyl-2-pyrrolidone (hereinafter abbreviated as NMP) is most soluble in the aromatic ester amide of the present invention, but is highly soluble in impurities as NMP. The inclusion of impurities in certain aromatic ester amides is avoided. Further, when the reaction is performed in NMP, the aromatic ester amide is precipitated in a crystalline form. For these reasons, NMP is preferably used.

The basic inorganic compound in the present invention has a solubility in water of 10 wt% or more, preferably 20%.
% or more, and examples thereof include aqueous ammonia, sodium carbonate, potassium carbonate, ammonium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, ammonium hydrogen carbonate, sodium acetate, potassium acetate, calcium acetate, lithium acetate, ammonium acetate and the like. However, particularly preferably, these aqueous solutions are used. These basic inorganic compounds may be used alone or as a mixture. If the solubility in water is less than 10 wt%, the amount of the basic inorganic compound mixed in the product aromatic ester amide increases and purification such as recrystallization and crystallization becomes necessary, which is not preferable.

The solubility of the hydrochloride of the basic inorganic compound in water in the present invention is 10 wt% or more, preferably 20 wt% or more. By using the above-mentioned basic inorganic compound, a hydrochloride of the basic inorganic compound satisfying this solubility is produced. If the solubility is less than 10 wt%, the amount of the hydrochloride salt of the basic inorganic compound mixed in the product aromatic ester amide increases, which requires purification such as recrystallization and crystallization, which is not preferable.

The order of addition of the aminobenzoic acid alkyl ester, terephthalic acid dichloride and amide solvent in the present invention is not particularly limited, and any of them may be added first. A terephthalic acid dichloride solution may be added to the aminobenzoic acid alkyl ester solution, or an aminobenzoic acid alkyl ester solution may be added to the terephthalic acid dichloride solution. Further, they may be added at the same time, or may be added as a solid. Preferably, the terephthalic acid dichloride solution is added dropwise to the aminobenzoic acid alkyl ester solution. Further, the basic inorganic compound may be added before reacting the both raw materials, or may be added after reacting the both raw materials. Preferably, it is added after reacting the above two raw materials. The basic inorganic compound may be added as a solid or as an aqueous solution. It is preferably added as an aqueous solution.

The charging ratio is suitable when the number of moles of the aminobenzoic acid alkyl ester with respect to terephthalic acid dichloride is from equimolar to 3-fold, and particularly preferably 2-fold. Further, the aminobenzoic acid alkyl ester may be added in a large excess. It is suitable to add the basic inorganic compound from the theoretical amount to twice the theoretical amount, but it is particularly preferable to add the theoretical amount.

When the terephthalic acid dichloride solution is added to the aminobenzoic acid alkyl ester solution or when the aminobenzoic acid alkyl ester solution is added to the terephthalic acid dichloride solution, the dropping rate is, for example, usually 0.1 l / min to 100 l. / Min, but 5 l / min ~
30 l / min is particularly preferred.

The solid content concentration of the reaction system is suitably 10 to 50 wt% excluding the basic inorganic compound, and preferably 1
It is 0 to 30 wt%.

The reaction temperature is, for example, 0 to 200 ° C.
Is suitable, preferably 0 to 150 ° C., and more preferably 50 to 100 ° C.

The reaction time is, for example, usually 0.5 to
It is 10 hours, but preferably 0.5 to 2 hours.

Solid-liquid separation of the reaction slurry and purification of the product aromatic ester amide are carried out by a filter, a centrifuge or a combination thereof. However, when productivity is taken into consideration, it is most preferable to continuously separate and purify using a centrifuge.

Purification of the product aromatic ester amide is carried out with water, hot water or a combination thereof. The amount of washing water used is suitably 1 to 50 l, preferably 10 l to 30 l, per 1 kg of the aromatic ester amide obtained by solid-liquid separation. No purification by recrystallization, crystallization, etc. is required, and the use of water or hot water as the washing liquid has great economic advantages. Further, by using a water-soluble basic inorganic compound and because the hydrochloride of the basic inorganic compound is water-soluble, the impurities in the aromatic ester amide can be efficiently removed by washing with water or hot water. be able to.

The aromatic ester amide which is the product is dried by a fluidized dryer, a conical dryer or a combination thereof.

The aromatic ester amide produced by the method of the present invention has a purity of 99.9 wt% or more. According to the present invention, an aromatic ester amide satisfying this purity can be produced only by washing with water or hot water. When the amount of impurities in the product aromatic ester amide increases, purification such as recrystallization and crystallization is required, which is not economical and adversely affects the polymerizability of the product aromatic ester amide. It becomes difficult to obtain a high molecular weight polymer.

The method of using the aromatic ester amide produced by the method of the present invention for the polymerization of amide TPE is as follows:
The method is not particularly limited, and a known method may be used. As a low molecular weight polymer having a hydrogen group terminal of an amide TPE component, it has a low glass transition point and is resistant to oxidative deterioration,
What has small absorbency may be used. As the polymerization catalyst, for example, metal alkoxides are preferable. In addition, hindered phenol anti-aging may be added as antioxidant. The polymerization is carried out in two steps. In the first step, glycol and aromatic ester amide are condensed to obtain a low molecular weight oligomer. In the second stage, the oligomers are condensed to obtain a high molecular weight polymer.

By the production method of the present invention, an aromatic ester amide which can be used as a hard segment of an amide TPE having high heat resistance and excellent mechanical properties can be produced in high purity without the need for purification such as recrystallization or crystallization. can do. The purity of the obtained aromatic ester amide is 99.9% or more.

[0033]

The present invention will be described below in detail with reference to examples, but the present invention is not limited to these examples. "%" Relating to concentration is by weight.

The analytical instruments and methods used for the analysis of the aromatic ester amide and amide TPE of the present invention are as follows.

(1) Purity of Aromatic Esteramide The purity of the aromatic ester amide was determined by HPLC using a C-8010 liquid chromatography system manufactured by Tosoh Corp. and a column.
It was measured using 2000 HHR with the eluent DMF (LiCl: 20 mmol / l) at a flow rate of 0.5 ml / min.

(2) Identification of aromatic estruamide The identification of aromatic estruamide was carried out by ¹ H-NMR and ¹³ C
-By NMR. ¹ H-NMR is JD manufactured by JEOL
Using NM-GSX270 type, the measurement was carried out in deuterated dimethyl sulfoxide under the conditions of 130 ° C. and 400 times of integration. ¹³ C-NMR was measured using the same machine in deuterated dimethylsulfoxide under the conditions of 130 ° C. and the number of integrations of 18,000 times.

(3) Reactivity of Aromatic Estruamide The reactivity of aromatic estruamide is amide-based TP obtained by polycondensation with polytetramethylene ether glycol.
It was evaluated by the melt index (MI) of E. Melt index is Takara Kogyo's melt indexer L2
It was measured at 230 ° C. under a load of 2.01 kg using 44, X416.

Example 1 To a 3 m ³ reactor equipped with a nitrogen inlet tube, 244 kg of ethyl 4-aminobenzoate and 1150 l of N-methyl-2-pyrrolidone were added and stirred to obtain a uniform solution.
° C. To a 3 m ³ reactor equipped with a separate nitrogen introducing tube, 570 l of N-methyl-2-pyrrolidone and 150 kg of terephthalic acid dichloride were added and stirred to form a uniform solution. This solution was added to the above solution at 70 ° C. for 1 hour. Dropped. After dropping, the reaction was performed for 1 hour. Crystals began to precipitate with the reaction. Then, it cooled to 30 degreeC. 10% ammonia water at 30 ° C. (Solubility in water 34.2 wt
%; 20 ° C.) 249 kg was added dropwise over 1 hour. The reaction slurry was solid-liquid separated by a centrifuge. Then, it was washed with 15 l of pure water per 1 kg of the produced aromatic ester amide. After drying under reduced pressure at 70 ° C. for 15 hours, an aromatic ester amide was obtained with a yield of 97%. For this identification, ¹ H-
The NMR measurement results are shown in FIG. 1, and the ¹³ C-NMR measurement results are shown in FIG.
It was shown to. Moreover, as a result of measuring the purity by HPLC, 9
It was 9.95%.

1.38 kg of the aromatic ester amide having a purity of 99.95% obtained here, polytetramethylene ether glycol having a number average molecular weight of 1484, 4.45 k
g, 2.68 kg of N-methyl-pyrrolidone, 5.8 g of hindered phenolic antioxidant Irganox 1330 manufactured by Ciba-Geigy and 7.1 g of titanium tetrabutoxide were charged into a 15 l autoclave. The reaction was carried out in a nitrogen stream at 210 ° C. for 30 minutes while removing ethanol produced. Subsequently, N-methylpyrrolidone was distilled off under reduced pressure over 2 hours. In addition, the internal temperature is 2
The temperature was raised to 30 ° C., and polymerization was carried out for 1 hour. When a predetermined torque value was reached, nitrogen was introduced to return the inside of the system to normal pressure. continue,
After pressurizing the system, the molten polymer was extracted as a strand from the lower part of the polymerization reactor and cut to obtain 4.8 kg of polymer pellets. The melt index value of this pellet was 9.8 g / 10 minutes, and a high molecular weight amide TPE could be obtained.

Example 2 223 kg of methyl 4-aminobenzoate and 1150 l of N-methyl-2-pyrrolidone were added to a 3 m ³ reactor equipped with a nitrogen introducing tube and stirred to obtain a uniform solution.
° C. To a 3 m ³ reactor equipped with a separate nitrogen introducing tube, 570 l of N-methyl-2-pyrrolidone and 150 kg of terephthalic acid dichloride were added and stirred to form a uniform solution. This solution was added to the above solution at 70 ° C. for 1 hour. Dropped. After dropping, the reaction was performed for 1 hour. Crystals began to precipitate with the reaction. Then, it cooled to 30 degreeC. 25% aqueous sodium carbonate solution at 30 ° C. (solubility in water 18.
1 wt%; 20 ° C.) 313 kg was added dropwise over 1 hour.
The reaction slurry was solid-liquid separated by a centrifuge. Then, it was washed with 15 l of pure water per 1 kg of the produced aromatic ester amide. After drying under reduced pressure at 70 ° C. for 15 hours, the yield was 96.
Aromatic ester amide was obtained in%. As a result of measuring the purity by HPLC, it was 99.94%. The amide TPE was polymerized in the same manner as in Example 1. This melt index value is 10.1 g / 10 minutes, and high molecular weight amide T
PE could be obtained.

Comparative Example 1 1156.3 g of ethyl 4-aminobenzoate and 4 L of N-methyl-2-pyrrolidone were added to a 10 L four-necked flask equipped with a nitrogen introducing tube and a thermometer and stirred to obtain a uniform solution. Obtained. To a 3 l dropping funnel separately equipped with a nitrogen introducing tube, 2 l of N-methyl-2-pyrrolidone and 710.6 g of terephthalic acid dichloride were added and stirred to form a uniform solution, and this solution was added dropwise to the above solution in 15 minutes. . After dropping, the reaction was performed for 1 hour. Crystals began to precipitate with the reaction. Then, it cooled to 30 degreeC. Calcium carbonate (solubility in water 0.0015wt%; 25 ° C)
350.3 g was added in 15 minutes. The reaction slurry was suction filtered and solid-liquid separated. Then, it was washed with 15 l of pure water per 1 kg of the produced aromatic ester amide. 70
After drying under reduced pressure at 15 ° C. for 15 hours, an aromatic ester amide was obtained with a yield of 97%. As a result of measuring the purity by HPLC, 97.
It was 26%. The amide TPE was polymerized in the same manner as in Example 1. This melt index value is 37.5 g / 1
It was 0 minutes, and a high molecular weight amide TPE could not be obtained.

Comparative Example 2 1156.3 g of ethyl 4-aminobenzoate and 4 l of toluene were added to a 10 l four-necked flask equipped with a nitrogen introducing tube and a thermometer and stirred to obtain a uniform solution. To a 3 l dropping funnel equipped with a separate nitrogen introducing tube, 2 l of toluene and 710.6 of terephthalic acid dichloride were added.
g and stir to make a uniform solution.
It was added dropwise in 5 minutes. After dropping, the reaction was performed for 1 hour. Crystals began to precipitate with the reaction. Then, it cooled to 30 degreeC. 10% ammonia water (solubility in water 34.2w
t%; 20 ° C.) 1192.1 g was added dropwise over 15 minutes.
The reaction slurry was suction filtered and solid-liquid separated. Then, it was washed with 15 l of pure water per 1 kg of the produced aromatic ester amide. 96% yield after drying under reduced pressure at 70 ° C for 15 hours
Then, an aromatic ester amide was obtained. As a result of measuring the purity by HPLC, it was 96.31%. The amide TPE was polymerized in the same manner as in Example 1. This melt index value is 38.2 g / 10 minutes, and high molecular weight amide-based T
PE could not be obtained.

[0043]

INDUSTRIAL APPLICABILITY According to the present invention, a highly pure and highly reactive aromatic ester amide which can be a hard segment of a thermoplastic elastomer having high heat resistance and excellent mechanical properties is recrystallized,
It is possible to simply and inexpensively manufacture without requiring a purification step such as crystallization.

[Brief description of drawings]

1 of the aromatic ester amides obtained in Example ¹
It is a figure which shows a H-NMR measurement result.

FIG. 2 shows ^{13 of} aromatic ester amide obtained in Example 1.
It is a figure which shows a C-NMR measurement result.

Claims (1)

[Claims] 1. The following general formula (1): (Wherein R represents an alkyl group having 1 to 10 carbon atoms), an aminobenzoic acid alkyl ester and terephthalic acid dichloride are reacted in an amide solvent, and then,
The following general formula (2) is characterized in that a basic inorganic compound having a solubility in water of 10 wt% or more is added. (In the formula, R represents an alkyl group having 1 to 10 carbon atoms).