JPS6360957A - Production of fatty acid bisamide - Google Patents

Abstract

PURPOSE:To obtain the titled compound useful as a mold-releasing agent for synthetic resin, in a colorless high-quality state without causing distilling off of raw material, by reacting a fatty acid with a diamine under pressure and returning the reaction product to normal pressure. CONSTITUTION:A fatty acid (e.g. lauric acid, myristic acid, palmitic acid, etc.) is made to react with a diamine (e.g. ethylenediamine, 1,3-diaminopropane, etc.) under pressure and the reaction is continued by returning to normal pres sure to obtain a fatty acid bisamide. The reaction can be carried out by charg ing both raw material components into a closed reaction system and heating the mixture at 150-300 deg.C, preferably 180-270 deg.C. The pressure in the reaction system increases to about 7-30kg/cm<2>. When the conversion to fatty acid bisamide reaches usually 85-95wt% based on the diamine, the reaction system is returned to normal pressure. High conversion can be easily attained in a short time by the normal pressure reaction and the reaction time can be shortened as a whole.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for producing fatty acid bisamides used as mold release agents, lubricants, pigment dispersants, etc. for synthetic resins.

[Conventional technology 3 Fatty acid bisamide is generally made by combining a fatty acid and a diamine with 15
It is obtained through a long heating reaction of ~20 hours. In order to carry out this reaction in a short time, it is necessary to raise the reaction temperature, but there have been problems such as coloration of the reactants due to high temperatures, deterioration of quality, and increase in by-products.

[Problems that the invention attempts to solve] As mentioned above,
j If the reaction is carried out at a high temperature to shorten the reaction time in the bisamidation reaction with fatty acid bisamide, a part of the raw material will be distilled out along with the reaction water, and the molar ratio of the fatty acid and diamine used will be lost, and the fatty acid There was a drawback that imidacillin was produced as a by-product due to intramolecular dehydration of monoamide, which is a reaction intermediate of bisamide, resulting in a decrease in yield and increased coloring.

Therefore, an object of the present invention is to produce fatty acid bisamide with high purity and good color in a short time without such drawbacks.

Points [Means for grouping the problems] The present inventors have conducted intensive studies to carry out the bisamidation reaction between fatty acids and diamines in a short time, and have found that if the reaction is carried out under pressure, the reaction will occur rapidly. Noboru/JllL does not distill the raw material, and by-products of imidacillin are kept to a minimum.
It was discovered that the bisamidation reaction progresses quickly and the coloring is reduced, and the present invention was achieved.

That is, the present invention relates to a method for producing a fatty acid bisamide, which is characterized in that a fatty acid and a diamine are reacted under pressure, and then the pressure is returned to normal and the reaction is continued.

[Structure and operation of the invention] In the present invention, a fatty acid and a diamine are first reacted under pressure. This reaction is usually carried out by charging the above-mentioned raw materials into a closed reaction system and heating the mixture to 150 to 300°C, preferably 180 to 270°C. The reaction system will be placed under pressure of approximately 7 to 30 kg/c++f.

In such a reaction under pressure, there is no distillation of diamine components or the like out of the system, so the molar ratio of both raw materials does not change, and the bisamidation reaction can proceed ideally. Moreover, since there is no distillation mentioned above, the temperature can be raised to a predetermined reaction temperature in a short time of about 10 to 30 minutes, that is, the temperature can be heated rapidly, so good results can be obtained in shortening the reaction time. can. Moreover, by shortening the reaction time, coloration of the reaction product is prevented, and furthermore, intramolecular dehydration of monoamidoamine as a reaction intermediate to form imidacillin is suppressed.

In addition, the by-product of imidacillin is further suppressed by the water present in the reaction system.

On the other hand, in the above-mentioned reaction under pressure, when the conversion rate of the diamine component to fatty acid bisamide (hereinafter simply referred to as conversion rate) reaches 85 to 95% by weight, further reaction progresses within the system. is inhibited by the water present in the The point at which the above conversion rate is reached is usually the point at which a predetermined reaction temperature is reached, that is, the time when the heating temperature has finished, and the time varies depending on the reaction temperature, but as mentioned above, about 10
It can be set for a short time of about 30 minutes.

In the present invention, when the above conversion rate is reached, the reaction system is returned to normal pressure, that is, it is opened to atmospheric pressure, and the reaction is allowed to proceed until a predetermined conversion rate is reached while water in the system is distilled out. The reaction temperature at this time is the same as the reaction temperature under pressure, but if necessary, it may be set somewhat lower or higher than the reaction temperature under pressure.

This reaction under normal pressure can easily achieve a high conversion rate, and the reaction time can be short.

Therefore, the overall reaction time is significantly shorter than conventional methods, usually 1 to 2 hours, and a fatty acid bisamide with a good hue and less by-products such as imidacillin can be obtained.

The raw fatty acids used in the present invention include saturated or unsaturated fatty acids, hydroxy fatty acids, etc., such as lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, erucic acid, behenic acid, ricinoleic acid, and hydroxystearic acid. Examples include acids. Raw material diamine includes ethylenediamine as aliphatic diamine,
3-diaminopropane, 1,4-diaminobutane, 1.
There are 5-diaminopentane, 1,6-cyamitsuhexane, etc., and aromatic diamines include metaxylene diamine,
These include tolylene diamine, ortho-phenylene diamine, meta-phenylene diamine, para-phenylene diamine, para-xylene diamine, and benzidine.

In the present invention, the reaction molar ratio of the fatty acid and diamine is 185 to 2.1:1, preferably 2.0 to 2.08.
:1. When the ratio is smaller than 1.85:1, the amount of monoamidoamine produced increases, and when it is larger than 2.1:1, not only the amount of unreacted fatty acids increases, but also the coloring becomes large.

In addition, in the reaction under pressure mentioned above, since air is blocked, color deterioration due to reaction heat will not occur even if the reaction temperature is set to a high temperature, as described above, but if necessary, a coloring inhibitor may be added. It can also be carried out by adding alkali metal borohydride, hypophosphorous acid, phosphorous acid, or alkali metal salts or alkaline earth metal salts of these acids.

[Effects of the Invention] According to the method of the present invention, raw materials are not distilled out due to the reaction under pressure in a sealed system, and the reaction can be carried out in a short time, producing fatty acid bisamides of good quality with less coloring. can get.

Note that the method of the present invention can also be applied to the amidation reaction of polyamines or monoamines such as triamines and tetramines with fatty acids, and the same effects as described above can be achieved in this case as well.

〔Example〕

The present invention will be explained below using examples. In addition, in the following, % means weight %, the conversion rate is a value calculated from the total amine value, and the production of imidacilline was estimated from the tertiary amine value.

Example 1 300j of stearic acid in an autoclave of 0.51;'
and ethylenediamine 31.99 (molar ratio 2.04:1)
After the air in the system was replaced with nitrogen, the system was sealed and the temperature was raised from the charging temperature of 80°C to the reaction temperature of 250°C over 30 minutes while stirring at 900 rpm. The reaction pressure at this time was 15.2 kg/c111, and the conversion rate was 944%.

Next, after the reaction pressure was released to normal pressure, the reaction was continued for an additional 30 minutes at the same temperature while passing nitrogen through, resulting in a conversion rate of 99.1%. The analysis results of the fatty acid bisamide thus obtained are shown in Table 1 below.

Examples 2 to 5 Fatty acid bisamides were obtained by carrying out the reaction in exactly the same manner as in Example 1, except for changing the reaction temperature and reaction time. The analysis results are summarized in Table 1 below.

Comparative Example 1 300 grams of stearic acid and 31.9 grams of ethylenediamine in a 0.51 inch four-hole flask! (molar ratio 2.04:1), and after replacing the air in the system with nitrogen, while collecting water generated in the amidation reaction outside the reaction system through nitrogen,
The reaction temperature was raised to 220°C in 1.5 hours, and then the temperature was increased to 220°C.
The reaction continued for 3.5 hours at 20°C.

The analysis results of the fatty acid bisamide thus obtained are shown in Table 1 below.

Comparative Examples 2 and 3 The reaction temperature was 200'C (Comparative Example 2) and 180'C.
C (Comparative Example 3), and the reaction was carried out in exactly the same manner as in Comparative Example 1, except that the reaction time was as shown in Table 1 below.
Fatty acid bisamide was obtained. The analysis results are shown in Table 1.

From the results in Table 1, it can be seen that in Examples 1 to 5, where the reaction was carried out under pressure in a closed system, the temperature increase time was 0.5 even if the reaction temperature was increased.
Although a short time may be sufficient, the heating time in the normal pressure system in Comparative Examples 1 to 3 is required to be 10 hours or more. In addition, Examples 1 to 5
The tertiary amine value was low in Comparative Examples 1 to 3, whereas the tertiary amine value was high in Comparative Examples 1 to 3, and the by-product of imidacillin was observed.

In this way, by incorporating the reaction under pressure in a sealed system into the temperature raising step of bisamidation, it is possible to perform the bisamidation reaction in a shorter time, prevent deterioration of hue, and suppress the by-product of imidacillin. Can be done.

Comparative Examples 4 and 5 Stearic acid 300y and ethylenediamine 31°97 (
A molar ratio of 204:1) was charged into four flasks, and the reaction temperature was raised to 220°C under normal pressure for 05 hours (Comparative Example 4).
) and 0.75 hours (Comparative Example 5)! f'? -warm,
The reaction was continued for an additional 35 hours to obtain fatty acid bisamide.

The analysis results are shown in Table 2 below. Note that the results of Comparative Example 1 are also listed in the same table for reference.

Table 2 From the results in Table 2 above, in Comparative Examples 4 and 5, the distillation of the amine component was larger than in Comparative Example 1, and the acid value was extremely high. I understand that it cannot be shortened.

Example 6 Using lauric acid as the raw fatty acid and paraxylene diamine as the diamine, a bisamidation reaction was carried out under the same conditions as in Example 1 to obtain a fatty acid bisamide. The results of the analysis are shown in Table 3.

Table 3 Example 7 Using behenic acid as the raw fatty acid and tolylene diamine as the diamine, the reaction temperature was 200°C and 250°C.
A fatty acid bisamide was obtained by carrying out a bisamidation reaction in the same column pit as in Example 1, except that C was used. The analysis results are shown in Table 4 below.

Table 4 As is clear from the results in Table 3.4 above, even when the types of raw fatty acids and diamines were changed, the results of Example 1
It can be seen that similar results are obtained.

Claims (1)

[Claims] (1) After reacting fatty acids and diamines under pressure,
A method for producing fatty acid bisamides characterized by continuing the reaction after returning to normal pressure.