Pesticide suspending agent containing bromothalonil and dithianon and preparation method thereof

Abstract

The invention discloses a pesticide suspending agent containing bromothalonil and dithianon and a preparation method thereof, and belongs to the technical field of pesticide preparation processing. The pesticide composition provided by the invention is prepared from the following components in percentage by mass: 1%-35% of bromothalonil, 1%-35% of dithianon, 1%-10% of a wetting agent, 1%-10% of a dispersing agent, 0%-10% of a performance improving agent, 0.1%-2% of a suspending aid, 1%-10% of an anti-freezing agent, 0.1%-0.6% of a defoaming agent, 0.05%-0.6% of a preservative, 0.1%-0.5% of a pH regulator and the balance of deionized water. According to the pesticide suspending agent disclosed by the invention, the selected wetting agent is combined with the special performance improving agent and the specific dispersing agent, so that the problems of heat storage and long-term stability of the suspending agent containing the low-melting-point bromothalonil can be well solved.

Description

Technical Field

[0003] This invention belongs to the field of pesticide formulation processing technology, specifically relating to a pesticide suspension containing bromodiphenyl ether and dicyandioxonine and its preparation method. Background Technology

[0005] Agricultural disease resistance is a global problem. With the continued use of chemical control methods year after year, increased pesticide use, and unscientific pesticide application, pathogen resistance is becoming increasingly serious, and the types of resistant pathogens are constantly increasing. At the same time, the intensive use of pesticides leads to excessive pesticide residues in agricultural products, environmental pollution, and increased pesticide costs for farmers, which is detrimental to sustainable agricultural development. Therefore, researching and developing highly efficient, low-toxicity, and environmentally friendly fungicides and their water-based formulations is of positive significance for sustainable agricultural development.

[0006] Bromhizobium was selected by Merck (now Syngenta) in the 1970s from over 30,000 chemicals as a more effective microbial agent than mercury-based formulations. Its chemical name is 1,2-dibromo-2,4-dicyanobutane. It is a broad-spectrum, low-toxicity, antifungal, and algicidal fungicide. It has the ability to kill mutant bacteria and inhibit and eradicate the growth of bacteria, fungi, and algae. It is a highly safe new fungicide. It is mainly used for the prevention and control of crop diseases, algae control in fishponds, and industrial wastewater treatment. It has good control effects on crop diseases, especially anthracnose.

[0007] Practical applications of bromuconazole have shown that it not only controls plant diseases and reduces yield loss, but also stimulates the activity of various enzymes in crops, increasing photosynthesis, resulting in dark green and robust leaves, and improving crop quality and yield. Bromuconazole is an excellent fungicide, effectively inhibiting and eradicating pathogens. However, long-term, high-dose, single-use application inevitably leads to pathogen resistance, significantly reducing its effectiveness. Combining it with other highly effective fungicides is an important way to resist resistance, delay its development, and extend its lifespan.

[0008] Dithianon, a fungicide developed by BASF Europe, has the chemical name 2,3-diacetonitrile-1,4-dithioanthraquinone. It is a quinone-based fungicide with multiple action sites, inhibiting a series of fungal enzymes through reactions with sulfur-containing groups and interference with cellular respiration, ultimately leading to disease and death. Dithianon is widely used as a protective fungicide both domestically and internationally, exhibiting excellent protective and curative activity. It is low in toxicity and safe for humans, livestock, bees, and fish. It can control various fungal diseases, showing good control effects against downy mildew, leaf spot, rust, leaf blight, brown rot, and ring rot in fruit trees and vegetables, especially anthracnose and ring rot. However, long-term single-use of dithianon carries a high risk of resistance. Combining it with different varietal components is one effective way to avoid the development of resistant pathogens.

[0009] There are over 30 registered certifications for bromodibenzonitrile-containing products on the market, but the formulations are mainly wettable powders, emulsifiable concentrates, microemulsions, and water-in-oil emulsions; no suspension concentrate formulations are registered. Although the following patent applications or patent grants exist for bromodibenzonitrile-dicyananthraquinone compound suspension concentrates: "A bactericidal composition," application number CN200910261170.4; "A synergistic composition for controlling fruit and vegetable diseases," application number CN201010011809.6; "A synergistic composition for controlling fruit and vegetable diseases," application number CN201210524524.1; "A highly effective bactericidal composition," application number CN201310172587.X; and "A bactericidal composition containing dicyananthraquinone and bromodibenzonitrile," application number CN201510733299.6, no bromodibenzonitrile-dicyananthraquinone suspension concentrate products have yet been industrialized. This is because bromocyanide has a very low melting point, only 52.5-53.2℃. Moreover, bromocyanide will undergo chemical reactions when it comes into contact with some anionic or nonionic additives, making it unstable. Therefore, it is difficult to maintain the long-term stability of bromocyanide-containing suspension products prepared using conventional suspending agents and conventional processes. Even after being stored at 45℃ for 6 weeks, the particle size is very likely to increase significantly or the product will become pasty.

[0010] This invention aims to effectively solve the stability problem of bromodiphenyl ether and anthraquinone suspensions by organically combining specially selected wetting and dispersing agents and other adjuvants. It also provides a low-toxicity, low-residue bactericidal composition containing bromodiphenyl ether with synergistic effects, slowing down the rate of bromodiphenyl ether resistance development and ensuring increased yields and income for vegetables, fruits, and other crops. Summary of the Invention

[0012] The purpose of this invention is to overcome the aforementioned deficiencies of existing technologies for bromodiphenyl ether suspension concentrates, and to provide a pesticide suspension concentrate containing bromodiphenyl ether and dicyananthraquinone, along with its preparation method, effectively solving the problem of product stability for bromodiphenyl ether suspension concentrates. This low-toxicity, low-residue, and synergistic fungicidal composition suspension concentrate containing bromodiphenyl ether and dicyananthraquinone can slow down the rate of bromodiphenyl ether resistance development, ensuring increased yields and income for crops such as vegetables and fruits.

[0013] To achieve the technical objective of this invention, this invention provides a pesticide suspension containing bromodiflubenzuron and dicyananthraquinone, which, by mass content, comprises 1%–35% bromodiflubenzuron, 1%–35% dicyananthraquinone, 1%–10% wetting agent, 1%–10% dispersant, 0%–10% performance improver, 0.1%–2% suspending agent, 1%–10% antifreeze, 0.1%–0.6% defoamer, 0.05%–0.6% preservative, 0.1%–0.5% pH adjuster, and deionized water to make up 100%.

[0014] The wetting agent is one or more of the following: modified rosin polyether-plant phenolic polyether (SP-SC3), methacrylate-ethyl acrylate-hydroxypropyl methacrylate polymer (FTRT® DS733), block polyether (DSC-2097), and block polyether (SP-3850).

[0015] The dispersant is selected from hydrophobically modified carboxylic acid copolymers (FTRT). ® One or more of the following: DS809, low pH carboxylic acid ester (DSC-2018), polyether sulfate (Witcolate PA), and polyether sulfate (Tersperse 2218).

[0016] The performance improver is one or more of the following: modified rosin diene polymer, 2-methyl-4-(1-methylethyl)-cyclohexene dimer, nano-crosslinked acrylic emulsion, and dicyclopentadiene.

[0017] The suspending agent is one or more of xanthan gum, aluminum magnesium silicate, and fumed silica.

[0018] The antifreeze is one or more of ethylene glycol, propylene glycol, glycerol, and urea.

[0019] The defoamer is one or more of polyalkylsiloxanes and alcohols.

[0020] The antifungal agent is one or more of sodium benzoate, benzoic acid, sorbic acid, and propyl hydroxybenzoate.

[0021] The pH adjuster is one or more of citric acid, lactic acid, glacial acetic acid, and salicylic acid.

[0022] This invention provides a method for preparing a pesticide suspension containing bromodiphenyl ether and anthraquinone, comprising the following steps: mixing bromodiphenyl ether technical, anthraquinone technical, wetting agent, dispersant, performance improver, suspending agent, antifreeze, preservative, pH adjuster, and deionized water, stirring the mixture evenly, and then grinding it in a pin mill (controlling the temperature below 20℃ and controlling the particle size D90≤3.5μm during the grinding process) to prepare a pesticide suspension containing bromodiphenyl ether and anthraquinone.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] The combined application of carefully selected wetting agents with special performance-modified carboxylic acid copolymers (or carboxylic acid esters) and specific polyether sulfate dispersants can effectively solve the problems of heat storage and long-term stability of suspensions containing low-melting-point bromocyanidins.

[0025] Suspension concentrates use water as a carrier, resulting in lower dust production compared to wettable powders; compared to emulsions, microemulsions, and other formulations, they are solvent-free, require less additives, are more environmentally friendly, and are safer for crops.

[0026] The application of performance improvers and the organic combination of wetting and dispersing agents give the formulation excellent physicochemical properties, superior dispersibility and adhesion (pesticide holding capacity), significantly improve the utilization rate of active ingredients during use, reduce pesticide usage, and save energy and reduce emissions.

[0027] The bactericidal composition suspension of bromodiphenyl ether and dicyananthraquinone has low toxicity, low residue and synergistic effect. It can slow down the rate of bromodiphenyl ether resistance development and ensure increased yield and income for vegetables, fruits and other crops.

[0028] All the additives used in this invention are biodegradable and environmentally friendly. Detailed Implementation

[0030] This application discloses a pesticide suspension containing bromodiphenyl ether and dicyandioxonine, and its preparation method. Unless otherwise specified, the experimental methods used in the following embodiments are conventional methods; the reagents and materials used in the following embodiments are commercially available unless otherwise specified.

[0031] Example 1: Preparation method of 30% bromochloronitrogen·dicyananthraquinone suspension:

[0032] The 30% bromobenzonitrile·dicyananthraquinone suspension was obtained by mixing 150 kg of bromobenzonitrile, 150 kg of dicyananthraquinone, 35 kg of modified rosin polyether-plant phenolic polyether (SP-SC3), 25 kg of hydrophobic modified carboxylic acid copolymer (FTRT® DS809), 20 kg of polyether sulfate (Witcolate PA), 40 kg of modified rosin diene polymer, 50 kg of propylene glycol, 5 kg of sodium benzoate, 1.2 kg of xanthan gum, 3 kg of magnesium aluminum silicate, 5 kg of polyalkylsiloxane, 2 kg of citric acid, and 513.8 kg of deionized water evenly and then grinding the mixture in a pin mill (the temperature was controlled below 20℃ and the particle size D90 ≤ 3.5 μm).

[0033] Example 2: Preparation method of 30% bromochloronitrogen·dicyananthraquinone suspension:

[0034] 150 kg of bromodibenzoic acid, 150 kg of dicyananthraquinone, 35 kg of modified rosin polyether-plant phenolic polyether (SP-SC3), 25 kg of hydrophobic modified carboxylic acid copolymer (FTRT® DS809), 20 kg of polyether sulfate (Witcolate PA), 50 kg of propylene glycol, 5 kg of sodium benzoate, 1.2 kg of xanthan gum, 3 kg of magnesium aluminum silicate, 5 kg of polyalkylsiloxane, 2 kg of citric acid, and 553.8 kg of deionized water were mixed evenly and then milled in a pin mill (the temperature was controlled below 20°C and the particle size D90 ≤ 3.5 μm) to obtain the 30% bromodibenzoic acid·dicyananthraquinone suspension.

[0035] Example 3: Preparation method of 30% bromochloronitrogen·dicyananthraquinone suspension:

[0036] A mixture of 100 kg bromobenzonitrile, 200 kg anthraquinone, 20 kg methacrylate-ethyl acrylate-hydroxypropyl methacrylate polymer (FTRT® DS733), 20 kg low pH carboxylic acid ester (DSC-2018), 20 kg polyether sulfate (Tersperse 2218), 30 kg 2-methyl-4-(1-methylethyl)-cyclohexene dimer, 30 kg glycerol, 6 kg benzoic acid, 1.2 kg xanthan gum, 3 kg magnesium aluminum silicate, 5 kg polyalkylsiloxane, 3 kg lactic acid, and 561.8 kg deionized water was thoroughly mixed and then milled in a pin mill (the temperature was controlled below 20℃ and the particle size D90 ≤ 3.5 μm) to obtain a 30% bromobenzonitrile·anthraquinone suspension.

[0037] Example 4: Preparation method of 30% bromochloronitrogen·dicyananthraquinone suspension:

[0038] A mixture of 200 kg bromobenzonitrile, 100 kg anthraquinone dicyanoquinone, 30 kg block polyether (DSC-2097), 20 kg hydrophobically modified carboxylic acid copolymer (FTRT® DS809), 40 kg polyether sulfate (Witcolate PA), 20 kg nano-crosslinked acrylic emulsion, 40 kg ethylene glycol, 5 kg sorbic acid, 1.1 kg xanthan gum, 3 kg magnesium aluminum silicate, 5 kg fumed silica, 5 kg alkylsilane ethylene oxide, 0.5 kg glacial acetic acid, and 530.4 kg deionized water was thoroughly mixed and then milled in a pin mill (the temperature was controlled below 20℃ and the particle size D90 ≤ 3.5 μm) to obtain a 30% bromobenzonitrile·antraquinone dicyanoquinone suspension.

[0039] Example 5: Preparation method of 40% bromochloronitrogen·dicyananthraquinone suspension:

[0040] A mixture of 200 kg of bromodibenzonitrile, 200 kg of dicyananthraquinone, 35 kg of block polyether (SP-3850), 20 kg of hydrophobic modified carboxylic acid copolymer (FTRT® DS809), 25 kg of polyether sulfate (Tersperse 2218), 20 kg of nano-crosslinked acrylic emulsion, 30 kg of urea, 2 kg of propylparaben, 1 kg of xanthan gum, 1.5 kg of magnesium aluminum silicate, 5 kg of polyalkylsiloxane, 2 kg of salicylic acid, and 458.5 kg of deionized water was thoroughly mixed and then milled in a pin mill (the temperature was controlled below 20℃ and the particle size D90 ≤ 3.5 μm) to obtain a 40% bromodibenzonitrile·dicyananthraquinone suspension.

[0041] Comparative Example 1: Preparation method of 30% bromochloronitrogen·dicyananthraquinone suspension:

[0042] The 30% bromobenzoic acid·anthraquinone suspension was obtained by mixing 150 kg of bromobenzoic acid, 150 kg of dicyananthraquinone, 35 kg of Morwet EFW (a mixture of alkyl naphthalene sulfonate and anionic wetting agent), 20 kg of Tersperse 2500 (a polymeric acrylic graft copolymer), 15 kg of Surfonic® POA (an ethylene oxide / propylene oxide block copolymer), 50 kg of propylene glycol, 5 kg of sodium benzoate, 1.2 kg of xanthan gum, 2 kg of magnesium aluminum silicate, 5 kg of polyalkylsiloxane, 2 kg of citric acid, and 564.8 kg of deionized water evenly and then grinding the mixture in a pin mill (the temperature was controlled below 20°C and the particle size D90 was controlled to be ≤3.5 μm).

[0043] Quality and technical measurement

[0044] The prepared suspension was tested under certain conditions, and the data obtained are shown in Table 1.

[0045]

[0046] -: This indicates a paste-like consistency that cannot be measured.

[0047] As can be seen from the data in Table 1, all indicators of Examples 1 and 2 meet the requirements for suspending agents and are of qualified quality. However, Control Example 1, after being stored at 54°C, turned into a paste and could not be used, thus failing to meet the quality requirements.

[0048] Drug retention determination

[0049] Test subject: Watermelon leaves

[0050] Test reagents: Example 1, Example 2.

[0051] The specific experimental method is as follows: Dilute the reagent according to the concentration used and stir well. Then, place a φ30mm petri dish on a 0.01% balance, zero it, and use a φ16mm punch to cut approximately 2cm of the solution. 2 Round watermelon leaves were first weighed and their mass recorded. Using pointed tweezers, the leaves were dipped into the prepared test solution, repeatedly soaked for 10 seconds, suspended for 10 seconds, and then placed in a petri dish to weigh the liquid-holding mass. Each measurement was repeated 10 times, and the average value was calculated to determine the difference in liquid retention. The test results are shown in Table 2.

[0052]

[0053] As can be seen from Table 2, the amount of pesticide residue on watermelon leaves in Examples 1 and 2 was significantly higher than that in Comparative Example 1.

[0054] Field efficacy trials

[0055] Test subject: Watermelon anthracnose

[0056] Test reagents: Example 1, Example 2, 25% bromodiphenyl ether emulsifiable concentrate, 50% dicyananthraquinone suspension concentrate, and water blank control.

[0057] Experimental method: Each cell area is 25m² 2Each treatment was repeated four times. The above formula was diluted with water and sprayed on the leaves. The efficacy was assessed before and after application by conducting a baseline survey before the first application, and then again on the 7th day after the first, second, and third applications. Five plants were randomly sampled from each plot, with four leaves sampled from each plant at five points (east, west, south, north, and center). Diseased leaves were graded using a nine-level system: 0, 1, 3, 5, 7, and 9, representing the lesion area as less than 0.5%, 6%–15%, 16%–25%, 26%–50%, and more than 50% of the total leaf area, respectively. The number of diseased leaves and the disease grade were recorded. The disease rate, disease index, and control effect were calculated. The experimental results are shown in Table 3.

[0058]

[0059] As can be seen from Table 3, Examples 1 and 2 are significantly effective against watermelon anthracnose. Compared with single agents, they have the advantages of high efficacy and long duration of action, and are safe for crops within the scope of this experiment.

[0060] Field trials showed that within the experimental concentration range, watermelons grew normally under each treatment, without obvious symptoms of phytotoxicity such as fading, deformity, or poor growth. No significant harmful effects of the pesticide on other organisms were also found. Therefore, the bromodicyclohexane·dicyandioxanone suspension pesticide suspension of this invention has excellent safety performance.

Claims

1. A pesticide suspension containing bromodiphenyl ether and dicyandioxonine, characterized in that, Based on mass content, it consists of 1%–35% bromodiphenyl ether, 1%–35% anthraquinone, 1%–10% wetting agent, 1%–10% dispersant, 0%–10% performance improver, 0.1%–2% suspending agent, 1%–10% antifreeze, 0.1%–0.6% defoamer, 0.05%–0.6% preservative, 0.1%–0.5% pH adjuster, and deionized water to make up 100%.

2. The pesticide suspension concentrate according to claim 1, characterized in that, The wetting agent is one or more of the following: modified rosin polyether-plant phenolic polyether (SP-SC3), methacrylate-ethyl acrylate-hydroxypropyl methacrylate polymer (FTRT® DS733), block polyether (DSC-2097), and block polyether (SP-3850).

3. The pesticide suspension concentrate according to claim 1, characterized in that, The dispersant is selected from hydrophobically modified carboxylic acid copolymers (FTRT). ® One or more of the following: DS809, low pH carboxylic acid ester (DSC-2018), polyether sulfate (Witcolate PA), and polyether sulfate (Tersperse 2218).

4. The pesticide suspension concentrate according to claim 1, characterized in that, The performance improver is one or more of the following: modified rosin diene polymer, 2-methyl-4-(1-methylethyl)-cyclohexene dimer, nano-crosslinked acrylic emulsion, and dicyclopentadiene.

5. The pesticide suspension concentrate according to claim 1, characterized in that, The suspending agent is one or more of xanthan gum, aluminum magnesium silicate, and fumed silica.

6. The pesticide suspension concentrate according to claim 1, characterized in that, The antifreeze is one or more of ethylene glycol, propylene glycol, glycerol, and urea.

7. The pesticide suspension concentrate according to claim 1, characterized in that, The defoamer is one or more of polyalkylsiloxanes and alcohols.

8. The pesticide suspension agent according to claim 1, characterized in that, The antifungal agent is one or more of sodium benzoate, benzoic acid, sorbic acid, and propyl hydroxybenzoate.

9. The pesticide suspension concentrate according to claim 1, characterized in that, The pH adjuster is one or more of citric acid, lactic acid, glacial acetic acid, and salicylic acid.

10. A method for preparing a pesticide suspension containing bromodiphenyl ether and dicyandioxonine, characterized in that, The technical grade bromodiphenyl ether, technical grade dicyananthraquinone, wetting agent, dispersant, performance improver, suspending agent, antifreeze, preservative, pH adjuster, and deionized water are mixed and stirred evenly, and then sand-milled in a pin mill (the temperature is controlled below 20℃ and the particle size D90≤3.5μm during the sand-milling process) to prepare a suspension of pesticide containing bromodiphenyl ether and dicyananthraquinone.

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