JPS6360956A - Production of fatty acid bisamide - Google Patents

Abstract

PURPOSE:To obtain the titled compound useful as a lubricant for synthetic resin, in colorless highly pure state without producing by-product, by terminating bisamidation reaction of a fatty acid with a diamine when the conversion of the reaction reaches a specific level and removing unreacted component by thin-film distillation. CONSTITUTION:A fatty acid (e.g. lauric acid, myristic acid, palmitic acid, etc.) is subjected to bisamidation reaction with a diamine (e.g. ethylenediamine, 1,3-diaminopropane, etc.) to obtain a fatty acid bisamide. In the above process, the reaction is terminated when the conversion to fatty acid bisamide reaches 85-98wt% based on the diamine and the unreacted components containing monoamidoamine are removed by thin-film distillation. The unreacted components can be efficiently separated and removed by the thin-film distillation in a short time without producing imidazoline as a by-product.

Description

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

[Prior art 1] Fatty acid bisamides are generally obtained by heating fatty acids and diamines under normal pressure for a long time to cause a reaction. In this case, in order to reduce unreacted components in the reaction product (including monoamidoamine as an intermediate),
There is a method of reacting at a high temperature of .degree. C. or higher for a long period of time, but there is a limit to the reduction of unreacted components, as well as the disadvantage that imidacillin is produced as a by-product and the color becomes poor. Another possible method is to purify the reactant by recrystallization, but this method has the drawbacks of complicated operations, high equipment costs, and high production costs.

[Problems to be Solved by the Invention] As described above, with the above conventional methods, it is difficult to easily produce fatty acid bisamides with high purity and good color, with few unreacted components and by-products. There was a point.

Therefore, an object of the present invention is to efficiently remove unreacted components in a short time without increasing by-products, and to obtain a fatty acid bisamide with high purity and good color.

[Means for solving the problem] By the way, when producing fatty acid bisamides, the bisamidation reaction can be completed in a relatively short time until the conversion rate of diamine to fatty acid bisamides is 85 to 98% by weight. However, it takes a long time for the reaction to proceed further. Unreacted components at this time include unreacted fatty acids and diamines, as well as monoamidoamine, which is a reaction intermediate.

As a result of repeated research aimed at obtaining fatty acid bisamides with high purity and good color, the present inventors found that after the reaction was carried out to the above-mentioned conversion rate of about 85 to 98% by weight, The inventors have discovered that it is possible to easily produce fatty acid bisamides with high purity and good brown color by removing unreacted components by thin film distillation, and have arrived at the present invention.

That is, in the bisamidation reaction of a fatty acid and a diamine, the present invention stops the reaction when the conversion rate of diamine to fatty acid bisamide (hereinafter simply referred to as conversion rate) reaches 85 to 98% by weight, and then forms a thin film. The present invention relates to a method for producing fatty acid bisamide, which is characterized in that unreacted components including monoamidoamine are removed by distillation.

ε Structure and operation of the invention] In the present invention, first, a bisamidation reaction between a fatty acid and a diamine is carried out. This bisamidation reaction may be carried out under normal pressure or under increased pressure.

Conducting the bisamidation reaction in a closed system under pressure has the advantage that the raw material does not distill out from the reaction system. The reaction temperature is 150-3
00°C, preferably 180-270°C. 150°
If the temperature is less than 300°C, the reaction rate is slow, and if it exceeds 300°C, by-products are likely to be produced.

The raw fatty acids used in the above bisamidation reaction include saturated or unsaturated fatty acids, hydroxy fatty acids, etc., such as lauric acid, myristic acid, palmitic acid,
Examples include stearic acid, oleic acid, erucic acid, behenic acid, ricinoleic acid, and hydroxystearic acid. In addition, as raw material diamines, aliphatic diamines include ethylenediamine, 1,3-diaminopropane, 1,4-
Examples include diaminobutane and 1,6-cyamitsuhexane, and aromatic diamines include metaxylene diamine, tolylene diamine, orthophenylene diamine, and paraxylene diamine.

The reaction molar ratio of fatty acid and sheamint in the bisamidation reaction is 1.85 to 2.1:1, preferably 2.0 to 2.1:1.
The ratio is 08:1. When it is less than 1.85:1, the yield decreases because the amount of monoamidoamine produced increases, and 2.1
: If it is larger than 1, not only will the amount of unreacted fatty acids increase, but the color will also become thicker.

One of the features of the present invention is that such bisamidation reaction is stopped when the conversion rate reaches 85 to 98% by weight. Here, if the conversion is stopped when the conversion is less than 85% by weight, the loss during distillation will increase, resulting in a disadvantage in terms of yield.

Furthermore, if the conversion rate exceeds 98% by weight, the reaction will take a long time, so there is no point in applying the method of the present invention. The reaction time to achieve the above conversion rate of 85 to 98% by weight varies considerably depending on the reaction temperature and the type of raw material components, but generally it is 3 to 5 hours under normal pressure and 0.05 hours under pressure. It takes about .5 to 1 hour.

The most important feature of the present invention is that after stopping the reaction at the above conversion rate, the unreacted components contained in the reactants, that is, the raw material components and the intermediate monoamide amine, are removed by thin film distillation. do. In other words, this thin film distillation allows the above-mentioned unreacted components to be efficiently separated and removed in a short time without producing imidacillin as a by-product, resulting in high purity and a good amber hue. It becomes possible to obtain fatty acid bisamide. On the other hand, even if a method such as simply distilling off the unreacted substances contained in the above-mentioned reactants under high vacuum is adopted, the unreacted components cannot be removed successfully and by-products are mixed in. and a decrease in hue cannot be avoided.

The distillation apparatus for thin film distillation is not particularly limited, and a wide variety of centrifugal thin film distillation apparatuses such as Smith type and Luer type, gravity flow type thin film distillation apparatus, etc. can be used. Distillation conditions vary depending on the type of raw material components and cannot be determined unconditionally, but the distillation temperature is usually 180 to 280°C and the degree of vacuum is about 1 to 10 mmH9.

[Effect of the invention 1 As described above, the production method of the present invention has the advantage that the reaction time can be shortened by distilling unreacted components, and also that unreacted components can be distilled off in a short time using a thin film distillation apparatus. For,
A highly purified fatty acid bisamide can be obtained with no by-products and little coloring.

The method of the present invention can also be applied to the amidation reaction between fatty acids and monoamines or polyamines, and in this case also the same effects as described above can be achieved.

[Implementation Series] The present invention will be described below with reference to Examples. In addition, in the following, both % and % mean weight %. Further, the conversion rate is calculated assuming that the total amine value is monoamidoamine, and the pure content is a value calculated assuming that the acid value is fatty acid and the total amine value is monoamidoamine. The amount of imidacillin produced can be estimated from the tertiary amine value.

Example 1 Stearic acid 2. OKy and ethylenediamine 0.21
7 (molar ratio 2,04:1) in a nitrogen gas atmosphere at 180-200'C for 4 hours to obtain an acid value of 8,1,
21 kg of a reaction product having a total amine value of 5.2, a tertiary amine value of 0.10, and a color (Gardner) of 4 was obtained. Conversion rate is 97
．． The purity was 92.5%.

The obtained reaction product was distilled using a Shinko Powdler (ceramic Smith type thin film distiller: Model 2-03?: +?1 degree 18
Distilled at 0°C or 250°C, vacuum level 2). The flow rate of the reaction product during distillation and the analytical values of the obtained product are shown in Table 1 below.

Table 1 From the results in Table 1, the amount of by-product imidacillin produced, estimated from the tertiary amine value, is small (0, 1
% or less), it can be seen that ethylene bisstearic acid amide with high purity and good color can be obtained.

Comparative Example 1 The reaction product 300j;' obtained in Example 1 was placed in a four-round flask, and the reaction was further continued at 220°C under normal pressure. The reaction product after 6 hours of reaction had a purity of 94.7%, an acid value of 6.5, a total amine value of 3.1, a tertiary amine value of 055, and a hue (Gardner) of 6. As described above, in the case of the normal pressure reaction, the reaction rate is very slow, and imidacillin is produced as a by-product, making it difficult for the reaction to proceed and increasing coloration.

Comparative Example 2 A bisamidation reaction was carried out in the same manner as in Example 1, and the reaction was interrupted after 4 hours. In order to remove remaining unreacted components, distillation was performed by blowing nitrogen at 220° C. and 3 to StzmHg for 3 hours. As a result, the purity was 92.
It went from 5% to 93.1%, and the hue (Gardner) went from 4 to 6.

Example 2 2.04 Kq of lauric acid and 0.68 Kg of paraxylene diamine (molar ratio 2.04:1) were mixed into 210-22
Reacted at 0°C for 5 hours, conversion rate 951%, acid value 155.
, total amine number 10.2, tertiary amine number 0.11. Hue (
Gardner) 5 fatty acid bisamide was obtained. This was distilled using the same Smith type thin film distillation machine as in Example 1. The distillation conditions were a temperature of 275° C., a vacuum degree of 7 mm H&, and the results shown in Table 2 below were obtained.

Table 2 Example 3 Behenic acid 2.08 to 9 tons! -Lylene diamine 0.37
h (molar ratio 2.04:1) at 210-220°C
The mixture was reacted for 5 hours to obtain a fatty acid bisamide with a conversion rate of 90.3%, acid % of 162, total amine value of 133, tertiary amine 'A of 0.10, and hue (Gardner) of 4. This was carried out at a distillation temperature of 260 using the same Smith-type thin film distiller as in Example 1.
Distillation was carried out at °C1 vacuum level of 3 mm l-1. The results are shown in Table 3 below.

Table 3 The results in Tables 2 and 3 above also show that the method of the present invention yields highly pure and light-colored fatty acid bisamides. .

Example 4 300 liters of stearic acid and 31.17 liters of ethylenediamine (molar ratio 2.04:l) were charged into a 0.51 liter autoclave, the air in the system was replaced with nitrogen, and the autoclave was sealed to 90 liters.
While stirring at 0 rpm, the temperature was raised from the charging temperature of 80'C to the reaction temperature of 22 CI'C in 0.5 hours. The reaction pressure immediately after heating up was 12.3 Kq/=, and the conversion rate was 9.
It was 39%. Next, after the reaction pressure was released to normal pressure, the reaction was continued for 0.5 hours at the same temperature, and the conversion rate was 98.
It became 0%.

The obtained reaction product was subjected to the same Smith type 7 (11
Distillation was carried out using a membrane distillation machine at 250° C., 3 mm vacuum, and 1 g. By this method, purity 9
97%, acid value 03, total amine value 0.2, tertiary amine value 0
．． 09, hue (Gardner) of 4 was obtained.

In this way, if the reaction is carried out under pressure and then thin film distillation is carried out, a highly purified fatty acid bisamide can be obtained in a shorter time.

Claims (1)

[Claims] (1) In the bisamidation reaction between fatty acids and diamines, the conversion rate of diamines to fatty acid bisamides is 85%.
A method for producing fatty acid bisamide, which comprises stopping the reaction when the concentration reaches ~98% by weight, and then removing unreacted components including monoamidoamine by thin film distillation.