CN112138604A - Double-carboxyl surfactant with anion-cation reversal capability and preparation method thereof - Google Patents

Abstract

The invention discloses a double carboxyl surfactant with anion and cation reversal ability and a preparation method thereof. The preparation method comprises: 1) adding dodecylamine and cyclobutane-3-enedicarboxylic acid anhydride into a three-necked flask, passing nitrogen gas through , carry out a nucleophilic addition-elimination reaction to generate an imide; then use LiAlH ₄ as a reducing agent to reduce the carbonyl group. 2) above-mentioned product is diluted, slowly add potassium permanganate, heat up and carry out oxidation reaction to generate carboxyl group, add sodium sulfite after the reaction is completed to remove excess potassium permanganate, use diatomaceous earth filtration and ethyl acetate to extract impurities, and collect the water phase. , adjust the pH to 2-4 to separate out the product, filter and dry to constant weight to obtain the final product. The surfactant has excellent anion and cation reversal properties, and the surfactant type can be changed according to the external environment. When the external environment is alkaline, it is an anionic surfactant, and when the external environment is acidic, it is a cationic surfactant.

Description

A kind of double carboxyl surfactant with anion and cation inversion ability and preparation thereof method

technical field

The invention belongs to the field of functional surfactants, and particularly relates to a dicarboxylate surfactant with anion and cation inversion ability and a preparation method thereof.

Background technique

Surfactants refer to amphiphilic compounds containing non-polar lipophilic groups and polar hydrophilic groups in the molecular structure, which can form directional arrangements at the gas-liquid and solid-liquid interfaces. Surface tension can effectively change the physical and chemical properties of the interface. Therefore, it is widely used in daily life, industry and agriculture and high-tech fields, and has become one of the important industries of chemical technology. Due to the weak foundation of the surfactant industry for a long time, the surfactants still have defects such as single variety, simple structure and backward technology, especially the high-end surfactant products and technologies, which still have a big gap with foreign countries.

SUMMARY OF THE INVENTION

In order to enrich the types of surfactants and endow the surfactants with functionalization, the present invention designs and prepares a dicarboxylate surfactant with anion and cation inversion ability and a preparation method thereof.

To achieve the above object, the present invention adopts the following technical solutions:

A double carboxyl surfactant with anion and cation inversion ability, the compound structural formula is:

As a further improvement of the present invention, the anion and cation properties of the surfactant are reversed according to the pH change of the external environment.

As a further improvement of the present invention, the dicarboxyl surfactant is an anionic surfactant when the external environment is an alkaline condition, and a cationic surfactant when the external environment is an acidic condition. The surfactant has excellent anion and cation reversal properties, and the surfactant type can be changed according to the external environment. When the external environment is alkaline, it is an anionic surfactant, and when the external environment is acidic, it is a cationic surfactant.

A kind of preparation method of the double carboxyl surfactant with anion and cation inversion ability, comprises the following steps:

Mix dodecylamine and cyclobut-3-enedicarboxylic acid anhydride, pass nitrogen, and carry out nucleophilic addition-elimination reaction at 150-200°C to generate imide;

Adding reducing agent LiAlH ₄ to the imide, reducing the carbonyl group at 0～35°C;

The oxidant potassium permanganate is then added, and the temperature is increased to 90-100° C. to carry out oxidation reaction to generate carboxyl groups, and after post-treatment, the final product is obtained.

As a further improvement of the present invention, in the nucleophilic addition-elimination reaction, the molar ratio of dodecylamine and cyclobut-3-enedicarboxylic anhydride is 1:2.

As a further improvement of the present invention, in the reduced carbonyl group, the molar ratio of LiAlH ₄ to dodecylamine is 1-1.2:1;

As a further improvement of the present invention, the amount of potassium permanganate is 1-2 times that of dodecylamine.

As a further improvement of the present invention, in the oxidation reaction, after the product after reducing the carbonyl group is diluted, potassium permanganate is slowly added at 0° C., and then the temperature is raised for the reaction.

As a further improvement of the present invention, the post-processing includes:

After the reaction, sodium sulfite was added to remove excess potassium permanganate, diatomaceous earth was used to filter and ethyl acetate was used to extract impurities, the aqueous phase was collected, the pH was adjusted to 2 to 4 to separate out the product, and the final product was obtained by filtration and drying to constant weight. product.

The present invention has the following advantages:

The preparation method of the invention generates imide through nucleophilic addition-elimination reaction of dodecylamine and cyclobut-3-enedicarboxylic anhydride, uses LiAlH ₄ as reducing agent to reduce imide; get the final product. The whole preparation method is simple and convenient, and the double carboxyl surfactant with anion and cation inversion ability is prepared.

The dicarboxyl surfactant with anion and cation reversal ability prepared by the invention can be applied to the fields of oil exploitation, crude oil recovery, soil restoration and the like. The surfactant has excellent anion and cation reversal properties, and the surfactant type can be changed according to the external environment. When the external environment is alkaline, it is an anionic surfactant, and when the external environment is acidic, it is a cationic surfactant.

Description of drawings

Fig. 1 is the synthetic route diagram of the dicarboxyl surfactant with anion and cation inversion ability obtained in Example 4.

FIG. 2 is a graph showing the change of the surface tension with pH of the dicarboxylated surfactant with anion and cation inversion ability obtained in Example 4. FIG.

Detailed ways

A kind of double carboxyl surfactant with anion and cation inversion ability of the present invention, the reaction equation of its preparation process is:

According to above-mentioned reaction mechanism, the present invention adopts following technical scheme:

A double carboxyl surfactant with anion and cation inversion ability, the structural formula of the surfactant is:

The method for preparing the above-mentioned dicarboxyl surfactant with anion and cation inversion ability, the steps of the method are:

1) Add dodecylamine and cyclobut-3-ene dicarboxylic anhydride dropwise in turn in a three-necked flask equipped with a reflux condenser, pass nitrogen, and react at 150-200° C. for 2-5 hours to carry out the first step of nucleophilic addition -elimination reaction generates imide, wherein the molar ratio of dodecylamine and cyclobut-3-enedicarboxylic acid anhydride is 1:2; then imide is reduced with LiAlH ₄ as reducing agent, wherein the molar ratio of LiAlH ₄ and dodecylamine is The molar ratio is 1-1.2:1, the reduction temperature is 0-35°C, preferably 20-35°C, and the reduction time is 4-6h.

2) After diluting the above product, slowly add potassium permanganate at 0°C, and the temperature rises for 10 to 12 h, wherein the amount of potassium permanganate is 1 to 2 times that of dodecylamine; sodium sulfite is used to reduce excess permanganate potassium acid, dilute hydrochloric acid was added dropwise until the pH of the reaction solution was 2-4, the product was precipitated, and the final product was obtained by filtration and drying to constant weight.

The surfactant can realize the reversal of the properties of anions and cations according to the change of the pH of the external environment.

The inversion principle of biscarboxyl surfactants with anion and cation inversion ability is realized by the following reaction:

The dicarboxyl surfactant with anion and cation inversion ability is an anionic surfactant when the external environment is an alkaline condition, and a cationic surfactant when the external environment is an acidic condition.

The technical solutions in the embodiments of the present invention will be described clearly and completely below. Obviously, the described embodiments are only some, but not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

Example 1

(1) Dodecylamine (18.5g, 0.1mol) and cyclobut-3-ene dicarboxylic anhydride (24.8g, 0.2mol) were successively added dropwise in a 250mL three-necked flask equipped with a reflux condenser, and nitrogen was passed 3 times, Then, it was heated to 180° C. to react for 3 h, and the completion of the reaction was monitored by TLC (Thin Layer Chromatography). After the reaction was completed, it was cooled to room temperature, 50 mL of distilled water was added, extracted three times with 80 mL of ethyl acetate, dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure to obtain a crude product, which was finally separated by column to obtain a colorless oily imide.

(2) 80 mL of tetrahydrofuran dried with metallic sodium was added to a 250 mL three-necked flask, cooled to 0° C. using an ice-salt bath, 3.8 g of LiAlH ₄ was slowly added in batches, and the imide dissolved in tetrahydrofuran was slowly added after stirring for 3 min. It was added dropwise to the three-necked flask, and after the addition was completed, it was raised to 25° C. for reaction for 4 hours. The completion of the reaction was monitored by TLC (ThinLayerChromatography). After the reaction was completed, it was cooled to 0°C, and under an ice-salt bath, 3.8 mL of H ₂ O, 3.8 mL of 15% NaOH aqueous solution and 11.4 mL of H ₂ O were sequentially added to quench the excess LiAlH ₄ , filtered, and the filter cake was washed with 20 mL of ethyl acetate. The filtrate was dried over anhydrous magnesium sulfate, concentrated under reduced pressure to obtain the crude product, and finally the product was obtained by column separation.

(3) above-mentioned product and 40mL distilled water are added in 250mL there-necked flask, be placed in ice-salt bath and be cooled to 0 ℃, slowly add potassium permanganate KMnO ₄ (20g, adding time is 40min), slowly heat up after adding all Reaction at 90°C for 12h. Add 80 mL of saturated aqueous sodium sulfite solution to the three-necked flask to quench the excess KMnO ₄ ; after the purple color fades, slowly lower the temperature and filter out the MnO ₂ generated in the reaction with diatomaceous earth while hot to obtain a clear filtrate; then the filtrate is washed with ethyl acetate. Extracting 3 times to remove impurities, collecting the aqueous phase, using dilute hydrochloric acid to adjust the pH of the aqueous phase to 2 to precipitate solids, filtering and drying to obtain the pure final product.

The yield of the product obtained in Example 1 was 58%.

Example 2

(1) Dodecylamine (18.5g, 0.1mol) and cyclobut-3-ene dicarboxylic anhydride (24.8g, 0.2mol) were successively added dropwise in a 250mL three-necked flask equipped with a reflux condenser, and nitrogen was passed 3 times, Then, it was heated to 150° C. for 2 h, and the completion of the reaction was monitored by TLC (Thin Layer Chromatography). After the reaction was completed, it was cooled to room temperature, 50 mL of distilled water was added, extracted three times with 80 mL of ethyl acetate, dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure to obtain a crude product, which was finally separated by column to obtain a colorless oily imide.

(2) 90 mL of tetrahydrofuran dried with metallic sodium was added to a 250 mL three-necked flask, cooled to 0° C. with an ice-salt bath, 4.18 g LiAlH ₄ was slowly added in batches, and the imide dissolved in tetrahydrofuran was slowly added after stirring for 3 min. It was added dropwise to a three-necked flask, and after the addition was completed, it was raised to 30° C. for reaction for 5 hours. The completion of the reaction was monitored by TLC (ThinLayerChromatography). After the reaction was completed, it was cooled to 0°C, and under an ice-salt bath, 4.2 mL of H ₂ O, 4.2 mL of 15% NaOH aqueous solution and 12.6 mL of H ₂ O were sequentially added to quench the excess LiAlH ₄ , filtered, and the filter cake was washed with 20 mL of ethyl acetate. The filtrate was dried over anhydrous magnesium sulfate, concentrated under reduced pressure to obtain the crude product, and finally the product was obtained by column separation.

(3) above-mentioned product and 40mL distilled water were added in 250mL three-necked flask, placed in ice-salt bath and cooled to 0°C, slowly added potassium permanganate KMnO ₄ (15.8g, addition time was 40min), slowly after adding all The temperature was raised to 100 °C and the reaction was carried out for 10 h. Add 80 mL of saturated aqueous sodium sulfite solution to the three-necked flask to quench the excess KMnO ₄ ; after the purple color fades, slowly lower the temperature and filter out the MnO ₂ generated in the reaction with diatomaceous earth while hot to obtain a clear filtrate; then the filtrate is washed with ethyl acetate. Extracted 3 times to remove impurities, collected the aqueous phase, adjusted the pH of the aqueous phase to 3 with dilute hydrochloric acid, and precipitated a solid, filtered and dried to obtain a pure final product.

The yield of the product obtained in Example 2 was 51%.

Example 3

(1) Dodecylamine (18.5g, 0.1mol) and cyclobut-3-ene dicarboxylic anhydride (24.8g, 0.2mol) were successively added dropwise in a 250mL three-necked flask equipped with a reflux condenser, and nitrogen was passed 3 times, Then, it was heated to 200° C. to react for 5 h, and the completion of the reaction was monitored by TLC (Thin Layer Chromatography). After the reaction was completed, it was cooled to room temperature, 50 mL of distilled water was added, extracted three times with 80 mL of ethyl acetate, dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure to obtain a crude product, which was finally separated by column to obtain a colorless oily imide.

(2) 100 mL of tetrahydrofuran dried with metallic sodium was added to a 250 mL three-necked flask, cooled to 0° C. using an ice-salt bath, 3.99 g of LiAlH ₄ was slowly added in batches, and the imide dissolved in tetrahydrofuran was slowly added after stirring for 3 min. It was added dropwise to a three-necked flask, and after the addition was completed, it was raised to 35° C. for reaction for 6 hours. The completion of the reaction was monitored by TLC (ThinLayerChromatography). After the reaction was completed, it was cooled to 0°C, and under an ice-salt bath, 4 mL of H 2 O, 4 mL of 15% NaOH aqueous solution and ₁₂ mL of H ₂ O were successively added to quench excess LiAlH ₄ , filtered, and the filter cake was washed with 20 mL of ethyl acetate. Dry over magnesium sulfate, concentrate under reduced pressure to obtain crude product, and finally obtain product through column separation.

(3) above-mentioned product and 40mL distilled water were added in 250mL there-necked flask, placed in ice-salt bath and cooled to 0°C, slowly added potassium permanganate KMnO ₄ (25g, addition time was 40min), slowly heat up after adding all Reaction at 90°C for 12h. Add 80 mL of saturated aqueous sodium sulfite solution to the three-necked flask to quench the excess KMnO ₄ ; after the purple color fades, slowly lower the temperature and filter out the MnO ₂ generated in the reaction with diatomaceous earth while hot to obtain a clear filtrate; then the filtrate is washed with ethyl acetate. Extracted 3 times to remove impurities, collected the aqueous phase, adjusted the pH of the aqueous phase to 4 with dilute hydrochloric acid, and precipitated a solid, filtered and dried to obtain a pure final product.

The yield of the product obtained in Example 3 was 53%.

Example 4

(1) Dodecylamine (18.5g, 0.1mol) and cyclobut-3-ene dicarboxylic anhydride (24.8g, 0.2mol) were successively added dropwise in a 250mL three-necked flask equipped with a reflux condenser, and nitrogen was passed 3 times, Then it was heated to 190° C. to react for 5 h, and the completion of the reaction was monitored by TLC (Thin Layer Chromatography). After the reaction was completed, it was cooled to room temperature, 50 mL of distilled water was added, extracted three times with 80 mL of ethyl acetate, dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure to obtain a crude product, which was finally separated by column to obtain a colorless oily imide.

(2) 80 mL of tetrahydrofuran dried with metallic sodium was added to a 250 mL three-necked flask, cooled to 0° C. with an ice-salt bath, 4.56 g of LiAlH ₄ was slowly added in batches, and the imide dissolved in tetrahydrofuran was slowly added after stirring for 3 min. It was added dropwise to a three-necked flask, and after the addition was completed, it was raised to 20° C. for reaction for 6 hours. The completion of the reaction was monitored by TLC (ThinLayerChromatography). After the reaction was completed, it was cooled to 0°C, and under an ice-salt bath, 4.6 mL of H ₂ O, 4.6 mL of 15% NaOH aqueous solution and 13.8 mL of H ₂ O were sequentially added to quench excess LiAlH ₄ , filtered, and the filter cake was washed with 20 mL of ethyl acetate. The filtrate was dried over anhydrous magnesium sulfate, concentrated under reduced pressure to obtain the crude product, and finally the product was obtained by column separation.

(3) above-mentioned product and 40mL distilled water were added in 250mL three-necked flask, placed in ice-salt bath and cooled to 0°C, slowly added potassium permanganate KMnO ₄ (31.6g, addition time was 40min), slowly after adding all The temperature was raised to 100 °C and the reaction was carried out for 10 h. Add 80 mL of saturated aqueous sodium sulfite solution to the three-necked flask to quench the excess KMnO ₄ ; after the purple color fades, slowly lower the temperature and filter out the MnO ₂ generated in the reaction with diatomaceous earth while hot to obtain a clear filtrate; then the filtrate is washed with ethyl acetate. Extracting 3 times to remove impurities, collecting the aqueous phase, using dilute hydrochloric acid to adjust the pH of the aqueous phase to 2 to precipitate solids, filtering and drying to obtain the pure final product.

The yield of the product obtained in Example 4 was 60%.

In order to characterize the structural characteristics of a biscarboxyl surfactant with anion and cation inversion ability, the biscarboxyl surfactant with anion and cation inversion ability synthesized in Example 4 was tested by hydrogen NMR, and the results are as follows :

¹ H NMR (300 MHz, DMSO): δ 12.13 (s, 2H), 2.78-2.43 (m, 8H), 1.36-1.26 (m, 20H), 0.88 (t, J=7.4 Hz, 3H) ppm.

To characterize the surface tension of a biscarboxyl surfactant with anion-cation inversion ability. The surface tension of the surfactant solution in Example 4 was measured by using a JK99C automatic surface tensiometer. First, a surfactant solution with a concentration of 0.01 mol/L was prepared, and its surface tension was tested at 25 °C. During the test, continuously read 5 data with rising and falling, and the difference between the 5 data is less than 1, take the average value of these data as the final surface tension value of the solution, and the test method is the platinum ring method. The surface tension of the surfactant solution as a function of pH is shown in Figure 2. It can be seen from the figure that as the pH value of the surfactant solution increases, its surface tension first increases and then decreases. When the pH is 6, the surface tension reaches a maximum of 65.2 mN/m, indicating that the surfactant has strong surface activity under acidic or alkaline conditions.

The above content is a further detailed description of the present invention, and it cannot be considered that the specific embodiments of the present invention are limited to this. Several simple deductions or substitutions should be regarded as belonging to the protection scope of the present invention determined by the submitted claims.

Claims (9)

1. A bi-carboxyl surfactant with anion-cation reversal capability is characterized in that the structural formula of the compound is as follows:

2. the dicarboxyl surfactant of claim 1, wherein the cationic and anionic properties of the surfactant are reversed according to the change of pH of the external environment.

3. The dicarboxyl surfactant of claim 2, wherein the dicarboxyl surfactant is an anionic surfactant under alkaline conditions in an external environment and a cationic surfactant under acidic conditions in an external environment.

4. A preparation method of a dicarboxyl surfactant with cation and anion reversal capability is characterized by comprising the following steps:

mixing dodecylamine and cyclobut-3-ene dicarboxylic anhydride, introducing nitrogen, and performing nucleophilic addition-elimination reaction at 150-200 ℃ to generate imide;

adding reducing agent LiAlH into imide₄Reducing carbonyl at 0-35 ℃;

and adding an oxidant potassium permanganate, heating to 90-100 ℃ for oxidation reaction to generate carboxyl, and performing post-treatment to obtain a final product.

5. The method according to claim 4, wherein the nucleophilic addition-elimination reaction is performed in a molar ratio of dodecylamine to cyclobut-3-enedicarboxylic anhydride of 1: 2.

6. The method according to claim 4, wherein in the reduced carbonyl group, LiAlH₄The mol ratio of the dodecylamine to the dodecylamine is 1-1.2: 1.

7. The method according to claim 4, wherein the amount of the potassium permanganate is 1 to 2 times the amount of the dodecylamine.

8. The preparation method according to claim 4, wherein in the oxidation reaction, after the product after carbonyl reduction is diluted, potassium permanganate is slowly added at 0 ℃, and then the temperature is raised for reaction.

9. The method of manufacturing according to claim 4, wherein the post-treatment comprises:

and after the reaction is finished, adding sodium sulfite to remove excessive potassium permanganate, filtering by adopting diatomite and extracting impurities by adopting ethyl acetate, collecting a water phase, adjusting the pH value to be 2-4 to separate out a product, and filtering and drying to constant weight to obtain a final product.

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