Urea type surfactant for dinotefuran suspending agent and preparation method thereof

Abstract

The invention discloses a urea type surfactant for a dinotefuran suspending agent and a preparation method of the urea type surfactant. Organic amine and isocyanate are adopted to generate a urea compound, and active amine hydroxyl, epoxypropane and ethylene oxide are adopted to generate the urea type surfactant; the polarity of the ureido structure is large, and surfactant molecules are more easily interacted through intermolecular hydrogen bonds or dipole moments, so that the surfactant molecules of the adsorption layer are more closely arranged, the viscosity and elasticity of the adsorption layer are increased, the stability of an adsorption film is enhanced, and the performance of the surfactant is improved; the surfactant contains polyether with a macromolecular long-chain structure and a urea structure with relatively strong polarity, forms characteristics similar to those of a chelate in a molecular structure, can possibly act with pesticide molecules to obtain a more stable molecular structure, and can solve many problems of a dinotefuran suspending agent in a stable dispersion system.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of surfactant technology, more particularly, the present application relates to a urea type surfactant for dinotefuran suspension concentrate and a preparation method thereof. BACKGROUND

[0002] Chemical pesticides are important tools for ensuring food security and world peace, and the rigid demand for pesticides by human beings exists for a long time. During the processing and use of pesticide formulations, pesticide surfactants are indispensable additives. With the diversification of pesticide formulations and the improvement of performance, pesticide surfactants also develop towards multi-varieties and serialization to meet the needs of processing different pesticide varieties and different formulations. In various new pesticide formulations, the use of common surfactants as wetting agents, dispersants, emulsifiers, defoamers, etc. cannot meet the performance requirements.

[0003] Dinotefuran is the only third-generation neonicotinoid insecticide developed by Japan Mitsui Chemical Corporation, which does not contain chlorine atom and aromatic ring structure. Its chemical structure and performance are quite different from existing neonicotinoid insecticides. Due to the structure containing 3-tetrahydrofuran methyl, it is called "furan nicotine", which has systemic, stomach poison and contact killing effects, and is very safe to mammals, aquatic organisms and birds, and can be used for insect control in rice, fruit trees, vegetables and many other crops.

[0004] The solubility of dinotefuran technical material in water is 40g, which is the main factor restricting the development of its suspension concentrate. The most important difficulty in developing dinotefuran suspension concentrate is to solve the Ostwald ripening phenomenon of the preparation during storage. SUMMARY

[0005] In order to overcome the above-mentioned defects of the prior art, the embodiments of the present application provide a urea type surfactant for dinotefuran suspension concentrate and a preparation method thereof.

[0006] A urea type surfactant for dinotefuran suspension concentrate, the chemical formula of the urea type surfactant is: Or ; In the above two chemical formulas, a and b are not 0, and a+b is between 5 and 100.

[0007] Further, R in the chemical formula is C 18 H 37 or C 16 H 33 or C 14 H 29 or C 12 H 25 or C8H 17 or C6H5 or C6H 13 or C3H7.

[0008] Further, R' in the chemical formula is C 18 H 37 or C 16 H 33 or C 14 H 29 or C 12 H 25 or C6H 12 or C7H6 or C 13 H 10 or C 10 H 18 .

[0009] A preparation method of urea type surfactant for dinotefuran suspension agent, characterized in that: the specific preparation steps are as follows: Step one: add organic amine A into the reactor, heat to 40-60℃, add reactant B, stir until mixed evenly, and keep the reaction for 1h; Step two: directly add catalyst C to the reaction product of step one, 100-140℃, replace the air in the reactor with nitrogen, replace 3 times, remove under vacuum for 0.5-1h, add propylene oxide, maintain the system pressure at 0.25-0.3MPa, continue to age after the feeding is completed, until the pressure in the system no longer decreases; continue to heat to 140-180℃, maintain the system pressure at 0.25-0.3MPa, continuously add ethylene oxide, continue to age after the feeding is completed, until the pressure in the system no longer decreases; cool the product, adjust the system to pH 5-7, and end the reaction; wherein the amount of catalyst C is 0.05-0.5% of the total weight of the materials in the two steps.

[0010] Further, the molar ratio of the organic amine A, the reactant B, the propylene oxide and the ethylene oxide is 1:2:(5-30):(5-30).

[0011] Further, the organic amine A in step one is selected from one or more of beef tallow amine, hexadecylamine, tetradecylamine, coconut amine, n-octylamine, aniline, hexylamine, and isopropylamine; the reactant B in step one is selected from one or more of octadecyl isocyanate, hexadecyl isocyanate, tetradecyl isocyanate, dodecyl isocyanate, hexamethylene diisocyanate, toluene diisocyanate, diphenyl methane diisocyanate, and isophorone diisocyanate.

[0012] Further, the catalyst C in step two is selected from one or more of potassium hydroxide, sodium hydroxide, tetrabutylammonium chloride, triethanolamine, dimethylamine, boron trifluoride etherate, sulfuric acid, phosphoric acid, zinc chloride, aluminum chloride, sodium benzenedicarboxylate, potassium methoxide, and sodium methoxide.

[0013] Further, in the step two, the aging reaction is continued for 1-1.5 hours after the feeding of propylene oxide is finished, and the aging reaction temperature ranges from 110 to 140 DEG C; the aging reaction is continued for 0.5-1 hour after the feeding of ethylene oxide is finished, and the aging reaction temperature ranges from 160 to 180 DEG C.

[0014] In the step two, the product is cooled to 70-80 DEG C, and a neutralizing agent is used to adjust the system to pH 5-7; the neutralizing agent is selected from one or more of acetic acid, aminoacetic acid, sulfamic acid, and dodecylbenzenesulfonic acid.

[0015] The application also discloses application of the urea surfactant in preparation of a pesticide dispersible water suspension agent; and a preparation method of the dispersible water suspension agent is as follows: 20% dinotefuran, 6% urea surfactant, 1.5% wetting agent fatty alcohol polyoxyethylene ether (AEO-5), 1% thickening agent magnesium aluminum silicate, 5% antifreezing agent ethylene glycol, 0.3% preservative sodium benzoate, 0.3% defoaming agent, and deionized water are configured according to a certain proportion, 1.2-1.5 times of zirconium beads in mass are added, and grinding is carried out in a sand mill; the grinding time is 1-2 hours, and the rotating speed is 900 r / min; the particle size D90 is less than 5 microns, and the pesticide dispersible water suspension agent is obtained.

[0016] Technical effects and advantages of the application: The application adopts organic amine and isocyanate to generate urea compounds, and active amine hydroxyl groups are used to generate urea surfactants with propylene oxide and ethylene oxide; the polarity of urea groups is large, and surfactant molecules are more easily arranged closely through intermolecular hydrogen bonds or dipole moment interaction, so that the viscosity and elasticity of the adsorption layer are increased, the stability of the adsorption film is enhanced, and the performance of the surfactant is improved; the polyether with a large molecule long chain structure and the urea structure with strong polarity in the surfactant form similar characteristics with "chelate", and a more stable molecular structure can be obtained through the interaction with pesticide molecules; in the stable dispersion system, dinotefuran is highly water-soluble, contains polar groups, has complex impurities, and has a low melting point; when the water suspension agent is prepared, problems such as austenite aging, precipitation during heat storage, and particle size growth are easily caused; the urea polyether surfactant with strong polarity in the application can solve the problems existing in dinotefuran suspension agent. PREFERRED EMBODIMENT

[0017] The technical solutions in the embodiments of the application will be described clearly and completely below, obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative work are within the protection scope of the application. EMBODIMENT

[0018] Put 269 g of tallow amine into a reactor, heat to 40-60℃, put in the reactant octadecyl isocyanate 295 g, stir until mixed evenly, and keep the reaction for 1 h; Put 200 g of the above reaction product into a 2 L autoclave, add 3 g of potassium hydroxide, heat to 100-140℃, replace the air in the reactor with nitrogen for 3 times, and remove under vacuum for 0.5-1 h; continuously feed 400 g of propylene oxide into the reactor, maintain the system pressure at 0.25-0.3 MPa, continue to age for 1 h after the feeding is completed, until the pressure in the reactor does not decrease; continue to heat to 140-180℃, maintain the total pressure of the system at 0.25-0.3 MPa, continuously add 400 g of ethylene oxide, continue to age after the feeding is completed, until the pressure in the system does not decrease; cool the product, adjust the pH of the system to 5-7, and end the reaction; cool the product to 80℃, adjust the pH of the system to 5 using acetic acid, and obtain the product; the product is tested for surface activity, and the surface tension at the critical micelle concentration is 28.4 mN / m. Example

[0019] Put 241 g of hexadecylamine into a reactor, heat to 40-60℃, put in the reactant hexadecyl isocyanate 267 g, stir until mixed evenly, and keep the reaction for 1 h; Put 200 g of the above reaction product into a 2 L autoclave, add 3 g of potassium hydroxide, heat to 100-140℃, replace the air in the reactor with nitrogen for 3 times, and remove under vacuum for 0.5-1 h; continuously feed 450 g of propylene oxide into the reactor, maintain the system pressure at 0.25-0.3 MPa, continue to age for 1 h after the feeding is completed, until the pressure in the reactor does not decrease; continue to heat to 140-180℃, maintain the total pressure of the system at 0.25-0.3 MPa, continuously add 430 g of ethylene oxide, continue to age after the feeding is completed, until the pressure in the system does not decrease; cool the product, adjust the pH of the system to 5-7, and end the reaction; cool the product to 80℃, adjust the pH of the system to 5 using acetic acid, and obtain the product; the product is tested for surface activity, and the surface tension at the critical micelle concentration is 29.1 mN / m. Example

[0020] Put 198 g of coconut amine into a reactor, heat to 40-60℃, put in the reactant dodecyl isocyanate 211 g, stir until mixed evenly, and keep the reaction for 1 h; The reaction product 200g is put into a 2L high-pressure reaction kettle, potassium hydroxide 3.9g is added, the temperature is raised to 100-140℃, nitrogen is introduced into the reaction kettle to replace the air in the reaction kettle, and the replacement is performed for 3 times, and vacuum is removed for 0.5-1h; 560g of propylene oxide is continuously fed into the reaction kettle, the system pressure is maintained at 0.25-0.3MPa, after the feeding is completed, the aging reaction is continued for 1h, and the kettle pressure is not reduced; continue to heat to 140-180℃, maintain the total pressure of the system at 0.25-0.3MPa, continuously add 540g of ethylene oxide, after the feeding is completed, continue to age the reaction, until the pressure in the system is not reduced; the product is cooled to reduce the temperature, the system is adjusted to pH 5-7, and the reaction is ended; the product is cooled to reduce the temperature to 80℃, the system is adjusted to pH 5 using acetic acid, and the product is obtained; the product is tested by surface activity test, and the surface tension at the critical micelle concentration is 27.4mN / m. Example

[0021] The coconut amine 396g is added into the reactor, heated to 40-60℃, the reactant hexamethylene diisocyanate 168g is put in, stirred until mixed uniformly, and incubated for 1h; The reaction product 200g is put into a 2L high-pressure reaction kettle, trichlorophosphine cyanide 2g is added, the temperature is raised to 100-140℃, nitrogen is introduced into the reaction kettle to replace the air in the reaction kettle, and the replacement is performed for 3 times, and vacuum is removed for 0.5-1h; 410g of propylene oxide is continuously fed into the reaction kettle, the system pressure is maintained at 0.25-0.3MPa, after the feeding is completed, the aging reaction is continued for 1h, and the kettle pressure is not reduced; continue to heat to 140-180℃, maintain the total pressure of the system at 0.25-0.3MPa, continuously add 515g of ethylene oxide, after the feeding is completed, continue to age the reaction, until the pressure in the system is not reduced; the product is cooled to reduce the temperature, the system is adjusted to pH 5-7, and the reaction is ended; the product is cooled to reduce the temperature to 80℃, the system is adjusted to pH 5 using acetic acid, and the product is obtained; the product is tested by surface activity test, and the surface tension at the critical micelle concentration is 25.6mN / m. Example

[0022] The n-octylamine 258g is added into the reactor, heated to 40-60℃, the reactant toluene diisocyanate 174g is put in, stirred until mixed uniformly, and incubated for 1h; 200g of the above reaction product was added to a 2L high-pressure reactor, along with 2.5g of potassium methoxide. The temperature was raised to 100–140°C, and nitrogen gas was introduced into the reactor to replace the air. This process was repeated three times, followed by vacuum removal for 0.5–1 hour. 700g of propylene oxide was continuously fed into the reactor, maintaining a system pressure of 0.25–0.3 MPa. After feeding, the aging reaction continued for 1 hour until the pressure inside the reactor no longer decreased. The temperature was then raised to 140–180°C, maintaining a total system pressure of 0.25–0.3 MPa. 600g of ethylene oxide was continuously added, and after feeding, the aging reaction continued until the pressure inside the system no longer decreased. The product was cooled, and the system was adjusted to pH 5–7 before the reaction was terminated. The product was cooled to 80°C, and the pH was adjusted to 5 using acetic acid to obtain the final product. The surface activity test showed that the surface tension at the critical micelle concentration was 27.7 mN / m. Example

[0023] Add 396g of coconut oil amine to the reactor, heat to 40-60℃, add 250g of diphenylmethane diisocyanate, stir until uniformly mixed, and keep warm for 1 hour. 200g of the above reaction product was added to a 2L high-pressure reactor, along with 2.5g of potassium methoxide. The temperature was raised to 100–140°C, and nitrogen gas was introduced into the reactor to replace the air. This process was repeated three times, followed by vacuum removal for 0.5–1 hour. 450g of propylene oxide was continuously fed into the reactor, maintaining a system pressure of 0.25–0.3 MPa. After feeding, the aging reaction continued for 1 hour until the pressure inside the reactor no longer decreased. The temperature was then raised to 140–180°C, maintaining a total system pressure of 0.25–0.3 MPa. 400g of ethylene oxide was continuously added, and after feeding, the aging reaction continued until the pressure inside the system no longer decreased. The product was cooled, and the system was adjusted to pH 5–7 before the reaction was terminated. The product was cooled to 80°C, and the pH was adjusted to 5 using acetic acid to obtain the final product. The surface activity test showed that the surface tension at the critical micelle concentration was 20.7 mN / m.

[0024] Examples 7-12: The urea-type polyether surfactants in Examples 1-6 above were used to prepare pesticide dispersible suspensions. The specific preparation method of the dispersible water suspension formulation is as follows: 20% of the technical grade dichlorvos, 6% of the above-mentioned urea-type polyether surfactant, 1.5% of the wetting agent fatty alcohol polyoxyethylene ether (AEO-5), 1% of the thickener magnesium aluminum silicate, 5% of the antifreeze agent ethylene glycol, 0.3% of the preservative sodium benzoate, 0.3% of the defoamer, and water were mixed in a certain proportion, and 1.2 to 1.5 times the mass of zirconium beads were added. The mixture was then ground in a sand mill for 1 to 2 hours at a speed of 900 r / min. The particle size D90 was less than 5 micrometers, thus obtaining the pesticide dispersible water suspension.

[0025] All percentage values ​​in the examples are mass percentages.

[0026] Comparative Example 1: The active ingredient consists of 20% fipronil, 6% polycarboxylate dispersant (Qingyu SP-27001), 1.5% wetting agent fatty alcohol polyoxyethylene ether (AEO-5), 1% thickener magnesium aluminum silicate, 5% antifreeze ethylene glycol, 0.3% preservative sodium benzoate, 0.3% defoamer, and water. These are mixed in a specific ratio, and 1.2–1.5 times their weight of zirconium beads are added. The mixture is then ground in a sand mill for 1–2 hours at a speed of 900 r / min. The particle size D90 is below 5 micrometers, resulting in a pesticide dispersible water suspension.

[0027] The pesticide dispersible water suspensions in Examples 7-12 and Comparative Example 1 were tested, and the results are shown in Table 1:

[0028] The beneficial effects of the present invention are as follows: (1) The organic amine and isocyanate are used to generate urea compounds, which contain active amine hydroxyl groups to generate urea-type surfactants with propylene oxide and ethylene oxide; the polarity of the urea group structure is relatively large, and the surfactant molecules are more likely to be arranged more tightly in the adsorption layer through intermolecular hydrogen bonds or dipole moment interactions, thereby increasing the viscosity and elasticity of the adsorption layer, enhancing the stability of the adsorption film, and improving the performance of the surfactant; the surfactant contains polyether with a large molecular long chain structure and urea structure with strong polarity, which form characteristics similar to "chelate" in the molecular structure, and may be able to obtain a more stable molecular structure and a stable dispersion system when interacting with pesticide molecules; (2) The technical grade of fipronil is highly water-soluble, contains polar groups, has relatively complex impurities, and has a low melting point. When preparing water suspensions, there are problems such as easy Auschwitz curing during sand milling, easy precipitation during heat storage, and easy particle size growth. The use of the urea-type polyether surfactant with strong polarity of the present invention can solve many problems existing in fipronil suspensions.

[0029] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A urea-type surfactant for use in fipronil suspension concentrate, characterized in that: The chemical formula of urea-type surfactants is: or ； In the two chemical formulas above, a and b are not both 0, and a+b is between 5 and 100.

2. The urea-type surfactant for fipronil suspension according to claim 1, characterized in that: In the chemical formula, R represents C. 18 H 37 Or C 16 H 33 Or C 14 H 29 Or C 12 H 25 or C8H 17 or C6H5 or C6H 13 Or C3H7.

3. The urea-type surfactant for fipronil suspension according to claim 1, characterized in that: In the chemical formula, R' represents C. 18 H 37 Or C 16 H 33 Or C 14 H 29 Or C 12 H 25 or C6H 12 or C7H6 or C 13 H 10 Or C 10 H 18 .

4. A method for preparing a urea-type surfactant for fipronil suspension concentrate, characterized in that: The specific preparation steps are as follows: Step 1: Add organic amine A to the reactor, heat to 40-60°C, add reactant B, stir until evenly mixed, and keep the reaction at this temperature for 1 hour; Step 2: Add catalyst C directly to the reaction product of Step 1. At 100-140℃, purge the air in the reactor with nitrogen gas three times, and vacuum degas for 0.5-1 hour. Add propylene oxide, maintaining the system pressure at 0.25-0.3 MPa. After feeding, continue the aging reaction until the system pressure no longer decreases. Continue heating to 140-180℃, maintaining the system pressure at 0.25-0.3 MPa, and continuously add ethylene oxide. After feeding, continue the aging reaction until the system pressure no longer decreases. Cool the product down, adjust the pH of the system to 5-7, and then terminate the reaction. The amount of catalyst C used is 0.05-0.5% of the total weight of the materials from both steps.

5. The method for preparing a urea-type surfactant for fipronil suspension according to claim 4, characterized in that: The molar ratio of organic amine A, reactant B, propylene oxide, and ethylene oxide is 1:2:(5-30):(5-30).

6. The method for preparing a urea-type surfactant for fipronil suspension according to claim 4, characterized in that: In step one, the organic amine A is selected from one or more of tallow amine, hexadecylamine, tetradecylamine, cocoylamine, n-octylamine, aniline, hexylamine, and isopropylamine; and in step one, the reactant B is selected from one or more of octadecyl isocyanate, hexadecyl isocyanate, tetradecyl isocyanate, dodecyl isocyanate, hexamethylene diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, and isophorone diisocyanate.

7. The method for preparing a urea-type surfactant for fipronil suspension according to claim 4, characterized in that: In step two, catalyst C is selected from one or more of potassium hydroxide, sodium hydroxide, tetrabutylammonium chloride, triethanolamine, dimethylamine, boron trifluoride ether, sulfuric acid, phosphoric acid, zinc chloride, aluminum trichloride, sodium phthalate, potassium methoxide, and sodium methoxide.

8. The method for preparing a urea-type surfactant for fipronil suspension according to claim 4, characterized in that: In step two, after the propylene oxide feed is completed, the aging reaction continues for 1 to 1.5 hours, with the aging reaction temperature ranging from 110 to 140°C; after the ethylene oxide feed is completed, the aging reaction continues for 0.5 to 1 hour, with the aging reaction temperature ranging from 160 to 180°C.

9. A method for preparing a urea-type surfactant for fipronil suspension according to claim 4, characterized in that: In step two, the product is cooled to 70-80°C, and the pH of the system is adjusted to 5-7 using a neutralizing agent; the neutralizing agent is selected from one or more of acetic acid, aminoacetic acid, aminosulfonic acid, and dodecylbenzenesulfonic acid.

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