Preparation method of high-fluorine-chlorine- imidacloprid suspension

Abstract

This invention relates to a method for preparing a high-fluorine chlorpyrifos-imidacloprid suspension, belonging to the field of pesticide technology. In preparing this high-fluorine chlorpyrifos-imidacloprid suspension, an synergist is added to form a water-retaining film on the surface of the droplets during residual spraying. This allows the droplets to be evenly dispersed on the object surface, preventing the liquid moisture from evaporating or being absorbed, thus improving the adhesion of the product to the target surface and prolonging its effect. The pesticide adheres to the object surface at a size of less than 5 micrometers. Upon contact with the target organism, a trace amount of penetrant promotes the absorption and activation of the active ingredient, thereby improving the efficacy. The product prepared by this invention is environmentally friendly, highly safe, and has a long-lasting effect on sanitary pests with a high contact kill rate.

Description

Technical Field

[0001] This invention relates to a method for preparing a high-fluorine chlorine-imidacloprid suspension concentrate, belonging to the field of pesticide technology. Background Technology

[0002] Suspension concentrates mainly consist of active ingredients, dispersants, thickeners, anti-settling agents, defoamers, antifreeze agents, and water. Their preparation process imposes specific requirements on pesticides: the active ingredient must have low solubility in water; the melting point of the solid active ingredient in the suspension system should preferably be above 60℃; and the active ingredient must have good chemical stability in water, resisting hydrolysis or decomposition. In pesticide suspension concentrates, the content of the active ingredient is generally between 5% and 50%. Generally, the finer the particle size and the more uniform the distribution, the higher the suspension rate. In my country, the particle size of suspension concentrates is generally controlled within the range of 1-5 μm.

[0003] Suspension concentrates, as the fastest-growing and most effective type of water-based formulation, possess high efficacy. Due to their minute active ingredient size, coupled with excellent wetting, spreading, and penetrating properties, they facilitate uptake and absorption by target organisms, thus exerting a strong effect on the target. Furthermore, the thickeners in suspension concentrates enhance the slow release effect of the active ingredient to some extent, prolonging the duration of action on the target organism.

[0004] During pesticide application, factors such as pesticide drift, evaporation, droplet bounce, and runoff, as well as poor wetting and spreading of the pesticide, coupled with inadequate penetration, absorption, or distribution, ultimately lead to a 10%-15% loss of the pesticide before it reaches the final site of action within the plant, thus reducing spraying efficiency. To improve spraying efficiency, synergists are typically added during spraying and mixed on-site. This method can prevent drift and improve the wetting, spreading, adhesion, penetration, and absorption performance of the pesticide solution on the target, ultimately achieving the goals of increased pesticide efficacy, reduced dosage, and lower residue levels.

[0005] Currently, most synergists used in the industry are added in the form of drum-mixed additives, also known as spray additives. The main function of these additives is to prevent droplet drift, evaporation, rebound, and runoff. However, packaging and transporting drum-mixed additives individually increases production, transportation, and usage costs, while the added packaging further pollutes the environment. Furthermore, most drum-mixed additives are corrosive and irritating, posing certain safety risks during use. Summary of the Invention

[0006] The purpose of this invention is to address the shortcomings of existing tank-mixing additives by proposing a method for preparing a high-fluorine chlorine-imidacloprid suspension. To address the numerous inconveniences of tank-mixing additives during use, this invention introduces synergists and penetrants into the formulation. Nonionic dispersants or polymers form a certain degree of adsorption on the particle surface, hindering particle aggregation and coagulation through steric hindrance. Simultaneously, the hydrophilic groups of the dispersant enhance the surface hydrophilicity of the particles, improving the strength of the interfacial water film. This achieves overall stability of the suspension system while significantly enhancing its effectiveness.

[0007] This invention solves the technical problem through the following technical solution: a method for preparing a high-fluorine chlorpyrifos-imidacloprid suspension, comprising the following steps:

[0008] Step 1: Add precisely measured amounts of imidacloprid and lambda-cyhalothrin technical to the reaction vessel and stir to disperse them. While stirring, add wetting and dispersing agent, defoamer, and thickener to the reaction vessel in sequence. Continue to shear and stir for 15 minutes to obtain a uniform slurry.

[0009] The second step is to turn on the cooling circulating water and control the water temperature between 0-7°C. Fill the sand mill with an appropriate amount of 1.0-1.2 type zirconia beads and perform wet sand milling on the mixed slurry. After grinding the particle size to less than 5μm, the material is discharged to obtain the sand milled slurry.

[0010] Third step: While stirring, continue to add penetrant, synergist, thickener, antifreeze, and preservative to the slurry in the sand mill, add the remaining water, and continue stirring for 15 minutes to make it completely mixed.

[0011] Step 4: Turn on the homogenizer and homogenize at a constant speed for 30 minutes to achieve a uniform state and obtain high-fluorine chlorine-imidacloprid suspension.

[0012] The content of each raw material component in the high-fluorine chlorine-imidacloprid suspension concentrate described in the above method, by mass percentage, is as follows:

[0013] The formula contains: 10.0g of high-efficiency cypermethrin, 3.0-15.0g of imidacloprid, 3.0-15.0g of synergist, 0.1-2.0g of penetrant, 2.0-5.0g of antifreeze, 0.1-3.0g of thickener, 0.1-0.5g of preservative, 0.1-0.5g of defoamer, 3.0-12.0g of wetting and dispersing agent, with the balance being water.

[0014] The wetting and dispersing agent includes at least one of the following: macromolecular block polyether, castor oil polyoxyethylene ether, nonionic hydroxyl polyethylene oxide block copolymer, novel grafted copolymer dispersion, alcohol ether emulsifier, nonylphenol polyoxyethylene ether, polyarylphenol alcohol ether copolymer, nonionic carboxylic acid polymer copolymer, butanol block polyether phosphate, nonionic EO-PO block copolymer, novel grafted comb carboxylate copolymer, sodium lauryl ether sulfate, and polycarboxylate emulsifying and dispersing agent.

[0015] The synergist includes at least one of the following: polyacrylamide, sodium polyacrylate, sodium tripolyphosphate, disodium dihydrogen pyrophosphate, hydroxyethyl cellulose and its derivatives, sodium carboxymethyl cellulose, hydroxypropyl cellulose, sucrose, cellulose derivatives, polyacrylamide, urea-formaldehyde resin, sodium benzoate, hydroxyalkyl acrylate, hydroxyethyl acrylate, water-soluble corn starch, polyether-modified trisiloxane, tetrasiloxane and polysiloxane compounds, polymer compounds, acetamide, oleamide, lauramide, eicosenoamide, hexadecylamide ethanol, and stearamide.

[0016] The penetrant includes at least one of the following: fatty alcohol polyoxyethylene ether, sodium di-2-octyl sulfonate, sodium diisooctyl succinate, isodecyl alcohol polyoxyethylene ether, isooctanol ether phosphate, ethylene glycol ethyl ether acetate, sodium alkyl sulfonate and its derivatives, sodium alkyl succinate sulfonate, and alkylphenol polyoxyethylene ether.

[0017] The thickener includes at least one of sodium sulfate, xanthan gum, magnesium aluminum silicate, gum arabic, gelatin, beeswax, stearic acid, chitosan and its derivatives, cellulose and its derivatives, silica, and diallyl phthalate.

[0018] The antifreeze agent includes at least one of acidic phosphate amine salt, polyethylene glycol, fatty acid amide, diethylene glycol, ethylene glycol, propylene glycol, and n-butanol.

[0019] The active components of the high-fluorine-chlorpyrifos-imidacloprid suspension prepared by the present invention are high-efficiency cypermethrin and imidacloprid. Both high-efficiency cypermethrin and imidacloprid exist in the form of a suspension. The pH value of the suspension is 5.0-8.0. The suspension rate of high-efficiency cypermethrin in the high-fluorine-chlorpyrifos-imidacloprid suspension is ≥90%, and the suspension rate of imidacloprid is ≥90%.

[0020] Compared to traditional formulations, this invention introduces a synergist to form an interfacial film on the droplet surface, effectively inhibiting water evaporation and thus improving droplet settling rate. Furthermore, this interfacial film forms a barrier on the object surface, preventing water absorption by the adherent, allowing droplets to adhere and spread better on the surface, thereby enhancing the product's duration of action and efficacy, while effectively controlling pest resistance. By adding a penetrant, trace amounts of penetrant in the pesticide solution significantly enhance its penetration after contact with the target organism, further strengthening efficacy. Integrating the synergist and penetrant into the high-fluorine-chlorpyrifos-imidacloprid suspension formulation utilizes non-ionic dispersants or polymers to form an adsorption layer on the particle surface, using steric hindrance to prevent particle aggregation and coagulation. Simultaneously, the hydrophilic groups of the dispersant enhance the hydrophilicity of the particle surface, improving the stability of the interfacial water film, thereby achieving overall system stability. The high-fluorine-chlorpyrifos-imidacloprid suspension of this invention has an active ingredient that can interfere with normal central nervous system conduction, leading to paralysis and eventual death of the target organism. This product has excellent rapid-acting properties, and is characterized by its ability to quickly knock down and kill pests such as mosquitoes, flies, and cockroaches. Detailed Implementation

[0021] The following examples further illustrate the above-described content of the present invention, but it should not be construed as limiting the scope of the subject matter of the present invention to the following examples. All technologies implemented based on the above-described content of the present invention fall within the scope of the present invention.

[0022] Unless otherwise specified, the experimental methods used in the following examples are conventional methods; unless otherwise specified, the reagents and materials used in the following examples are commercially available.

[0023] The present invention will be further described below with reference to embodiments. Unless otherwise specified, all percentages in the following embodiments refer to weight percentages.

[0024] Example

[0025] This embodiment discloses a method for preparing a high-fluorine chlorine-imidacloprid suspension:

[0026] S1. Add precisely measured amounts of imidacloprid and lambda-cyhalothrin technical grade to the reaction vessel, stir to disperse them, and while stirring, add wetting and dispersing agent, defoamer, and thickener to the reaction vessel in sequence, and continue to shear and stir for 15 minutes to obtain a uniform slurry.

[0027] S2. Turn on the cooling circulating water and control the water temperature between 0-7°C. Fill the sand mill with an appropriate amount of 1.0-1.2 type zirconia beads and perform wet sand milling on the mixed slurry. After grinding the particle size to less than 5μm, release the material to obtain the sand milled slurry.

[0028] S3. While stirring, continue to add penetrant, synergist, thickener, antifreeze, and preservative to the slurry in the sand mill, add the remaining water, and continue stirring for 15 minutes to make it completely mixed.

[0029] S4. Turn on the homogenizer and homogenize at a constant speed for 30 minutes to achieve a uniform state and obtain high-fluorine chlorine-imidacloprid suspension.

[0030] The proportions of each raw material component are shown in Table 1 below.

[0031] Table 1

[0032]

[0033]

[0034] Three batches were produced consecutively using the method described in the example to verify its thermal storage stability.

[0035] Comparative Example

[0036] This comparative example was prepared using the following method:

[0037] S1. Add water to the reaction vessel, and while stirring, add imidacloprid and lambda-cyhalothrin to the reaction vessel in sequence, and add adjuvants and synergists to the reaction vessel in sequence; the adjuvants include wetting agents, dispersants, defoamers, penetrants and thickeners, and mix them evenly by high-speed stirring to obtain a mixed slurry.

[0038] S2. The mixed slurry is subjected to sand milling to obtain a sand-milled slurry;

[0039] S3. While stirring, add antifreeze and preservative to the sand-milling slurry, and use the remaining water to make up to 100%.

[0040] S4. Homogenize the material using a high-speed shearing machine to obtain a high-fluorine chlorpyrifos-imidacloprid product.

[0041] The proportions of each raw material component are shown in Table 2 below.

[0042] Table 2

[0043]

[0044]

[0045] Three batches were produced consecutively using the method of the control example.

[0046] The technical specifications of the 31% high-fluorine chlorpyrifos-imidacloprid suspension concentrate prepared by this invention are shown in Table 3:

[0047] Table 3

[0048]

[0049]

[0050] The initial test results of various indicators of the product at room temperature in the example are as follows:

[0051] Table 4

[0052]

[0053] The initial test results of various indicators of the product's thermal storage in the example are shown in Table 5:

[0054] Table 5

[0055]

[0056]

[0057] Biological experiments:

[0058] Target species: Culex pipiens pallens and houseflies;

[0059] Test method: Residual spraying test, according to GB / T 13917.1-2009 Indoor efficacy test and evaluation of pesticide registration sanitary insecticides Part 1: Residual spraying test in sprays, the knockdown time KT50 and 24h mortality rate were determined 7-90 days after coating on different surfaces.

[0060] Experimental treatment: The formulation examples and control examples were diluted 50 times with water to prepare a diluent. Then, the solution was evenly coated on the test plate at a dosage of 150 mg / m². The knockdown time KT50 and 24-hour mortality rate were measured 7-90 days after coating.

[0061] The results of the assays for Culex pipiens pallens and houseflies are shown in Tables 6 and 7 below.

[0062] Table 6. Test results of the product's knockdown performance against Culex pipiens pallens and houseflies.

[0063]

[0064]

[0065] Table 7. Test results of the product's lethality against Culex pipiens pallens and houseflies.

[0066]

[0067]

[0068] Biological experiments have demonstrated that the control group was far less effective than the example group in residual spraying. This proves that after the components were co-melted and synergists and crystal penetrants were added, the effective ingredients of the example group could exist as tiny particles in residual spraying, which could better adhere to the object surface and have a better biological effect on the target (knockout effect and lethal effect).

[0069] As can be seen from the above embodiments, the preparation method of the present invention significantly improves the efficacy and duration of action while ensuring stable quality.

[0070] In addition to the above-described embodiments, the present invention may have other implementations. All technical solutions formed by equivalent substitution or equivalent transformation fall within the protection scope claimed by the present invention.

Claims

1. A process for the preparation of high fluoro-chloro- imidacloprid suspension concentrate characterized by: Includes the following steps: Step 1: Add imidacloprid and lambda-cyhalothrin technical material to the reaction vessel and stir to disperse them. While stirring, add wetting and dispersing agent, defoamer and thickener to the reaction vessel in sequence. Continue to shear and stir for 15 minutes to obtain a uniform slurry. The second step involves filling a sand mill with 1.0-1.2 type zirconia beads while maintaining a water temperature of 0-7°C for cooling circulating water. The mixed slurry is then subjected to wet sand milling to grind the particles to a size of less than 5μm before discharging the material to obtain the sand milled slurry. Third step: While stirring, continue to add penetrant, synergist, thickener, antifreeze, and preservative to the slurry in the sand mill, add the remaining water, and continue stirring for 15 minutes to make it completely mixed. Step 4: Continue homogenization at a constant speed for 30 minutes to achieve a homogeneous state, thus obtaining high-fluorine chlorine-imidacloprid suspension.

2. The process for the preparation of high fluoro-chloro- imidacloprid suspension according to claim 1, characterized in that: In the first step, the imidacloprid technical material is pretreated by adding water into the reactor, turning on the stirring device, slowly adding high-efficiency cypermethrin and imidacloprid technical material, continuing to add emulsifying dispersant and defoamer, and adjusting the stirring speed until it is completely mixed. After adding thickener again, stir for 15 minutes, turn on the shearing machine to break up the particles in the material to obtain a uniform material.

3. The process for the preparation of high fluoro-chloro- imidacloprid suspension according to claim 1, characterized in that: In the second step, 80% of the volume of zirconia beads are filled into a 50L sand mill. The feed pump is turned on to pump the slurry into the sand mill at a uniform speed. During the sand milling process, the slurry temperature at the outlet of the sand mill is controlled to be below 30℃. This sand milling uses a three-stage series sand milling method to control the particle size of the produced slurry to be 2.5-5μm.

4. The method of claim 1, wherein the preparation of the high fluoro-chloride- imidacloprid suspension agent is characterized by: In the third step, the sand mill slurry is transferred to the reaction vessel, the sand mill is rinsed with water, and after all the slurry is transferred to the reaction vessel, the stirring is started, and the penetrant, synergist, thickener, antifreeze and preservative are added. The remaining water is added, and the mixture is stirred until uniform. Then the shearing machine is started and sheared for 30 minutes to obtain a uniform dispersion of high-fluorine chlorpyrifos-imidacloprid.

5. The method of claim 1, wherein the preparation of the high flu- chloro- imidacloprid suspension agent is characterized by: The wetting and dispersing agent includes at least one of the following: macromolecular block polyether, castor oil polyoxyethylene ether, nonionic hydroxyl polyethylene oxide block copolymer, novel grafted copolymer dispersion, alcohol ether emulsifier, nonylphenol polyoxyethylene ether, polyarylphenol alcohol ether copolymer, nonionic carboxylic acid polymer copolymer, butanol block polyether phosphate, nonionic EO-PO block copolymer, novel grafted comb carboxylate copolymer, sodium lauryl ether sulfate, and polycarboxylate emulsifying and dispersing agent.

6. The method of preparing high fluoro-chloro- imidacloprid suspension according to claim 1, characterized in that: The synergist includes at least one of the following: polyacrylamide, sodium polyacrylate, sodium tripolyphosphate, disodium dihydrogen pyrophosphate, hydroxyethyl cellulose and its derivatives, sodium carboxymethyl cellulose, hydroxypropyl cellulose, sucrose, cellulose derivatives, polyacrylamide, urea-formaldehyde resin, sodium benzoate, hydroxyalkyl acrylate, hydroxyethyl acrylate, water-soluble corn starch, polyether-modified trisiloxane, tetrasiloxane and polysiloxane compounds, polymer compounds, acetamide, oleamide, lauramide, eicosenoamide, hexadecylamide ethanol, and stearamide.

7. The process for the preparation of high fluoro-chloro- imidacloprid suspension as claimed in claim 1 wherein: The thickener includes at least one of sodium sulfate, xanthan gum, magnesium aluminum silicate, gum arabic, gelatin, beeswax, stearic acid, chitosan and its derivatives, cellulose and its derivatives, silica, and diallyl phthalate.

8. The process for the preparation of high fluoro-chloro- imidacloprid suspension according to claim 1, characterized in that: The penetrant includes at least one of the following: fatty alcohol polyoxyethylene ether, sodium di-2-octyl sulfonate, sodium diisooctyl succinate, isodecyl alcohol polyoxyethylene ether, isooctanol ether phosphate, ethylene glycol ethyl ether acetate, sodium alkyl sulfonate and its derivatives, sodium alkyl succinate sulfonate, and alkylphenol polyoxyethylene ether.

9. The process for the preparation of high fluoro-chloro- imidacloprid suspension according to claim 1, characterized in that: The content of each raw material component in the high-fluorine chlorpyrifos-imidacloprid suspension by mass percentage is as follows: high-efficiency cypermethrin 10.0, imidacloprid 3.0-15.0, synergist 3.0-15.0, penetrant 0.1-2.0, antifreeze 2.0-5.0, thickener 0.1-3.0, preservative 0.1-0.5, defoamer 0.1-0.5, wetting and dispersing agent 3.0-12.0, and the balance being water.

10. The method for preparing the high fluoro-chloride- imidacloprid suspending agent according to any one of claims 1-9, characterized in that: The active components of the prepared high-fluorine-chlorpyrifos-imidacloprid suspension are lambda-cyhalothrin and imidacloprid, both of which exist in the form of a suspension. The pH value of the suspension is 5.0-8.0, and the suspension rate of lambda-cyhalothrin and imidacloprid in the high-fluorine-chlorpyrifos-imidacloprid suspension is ≥90%.

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