Pyraclostrobin thioneb water dispersible granule and preparation process thereof

Abstract

The invention provides a pyraclostrobin thioneb water dispersible granule and a preparation process thereof, and belongs to the technical field of pesticide preparations. The preparation process comprises the following steps: loading pyraclostrobin thioneb on modified tungsten trioxide nanoflowers; the micro-capsule of the tungsten trioxide nanoflower loaded with the pyraclostrobin metiram is flexible; preparing a polymer binder; preparing a nano auxiliary agent; and preparing the water dispersible granules. Pyraclostrobin thioneb is loaded by tungsten trioxide nanoflowers, and the tungsten trioxide nanoflowers have unique optical performance, can absorb and scatter light rays such as ultraviolet rays and reduce direct irradiation of the light rays to pyraclostrobin thioneb, so that decomposition and failure caused by photolysis of the pyraclostrobin thioneb are reduced, the validity period and the lasting period of the pesticide are prolonged, and the pesticide is safe and environmentally friendly. Meanwhile, the slow release speed of pyraclostrobin thioneb can be adjusted after modification of polyethylene glycol and lauryl sodium sulfate, so that the pesticide can continuously exert the pesticide effect on the surfaces of crops.

Description

Technical Field

[0001] The invention relates to the technical field of pesticide preparations, and in particular to a methocarb water dispersible granule and a preparation process thereof. Background Art

[0002] In the field of global agricultural production, crop diseases have always been one of the key problems threatening food security, fruit and vegetable quality, and cash crop yields. According to statistics from the Food and Agriculture Organization of the United Nations, plant diseases caused by various fungi, bacteria, and viruses cause a 20-40% reduction in global crop yields each year, with economic losses of hundreds of billions. In order to effectively prevent and control these diseases, the development and application of pesticides are crucial.

[0003] As a well-known protective fungicide, metirol belongs to the class of ethylene dithiocarbamate compounds. With its excellent broad-spectrum fungicidal properties, it can protect against many common diseases of crops, such as downy mildew and anthracnose of vegetables, black spot and scab of fruits, and rust and powdery mildew of field crops, which can be curbed to a certain extent. After metirol is applied to the surface of crops, the dithiocarbamate groups released by it can strongly chelate the key enzymes in the pathogens, thereby blocking the normal metabolic process of the pathogens, inhibiting their growth and reproduction, and achieving the goal of disease prevention. However, metirol also has some limitations. Its single-use effect period is short, and with the continuous breeding and invasion of pathogens during the growth cycle of crops, frequent application of drugs is required, which undoubtedly greatly increases the planting cost and labor input; in addition, the long-term and single use of metirol causes some pathogens to gradually develop drug resistance, and the efficacy of the drug is greatly reduced, and it is impossible to protect crops stably and efficiently.

[0004] At the same time, pyraclostrobin, as a star product among methoxyacrylate fungicides, has the dual activity of systemic treatment and protection. Its mechanism of action is extremely unique. It can strongly inhibit the activity of complex III of the pathogen's mitochondrial respiratory chain, interfere with the pathogen's energy generation system, and cause the pathogen to stop growing and eventually die due to lack of energy. Pyraclostrobin not only has excellent bactericidal efficacy, but also can promote crop growth, enhance the crop's own ability to resist adverse stress, and help crops maintain a healthy physiological state. However, relying solely on pyraclostrobin is not a perfect solution. In planting scenarios where diseases are prevalent and environmental conditions are complex and changeable, its protection range is not enough to cover all common diseases. When used alone, it cannot build a comprehensive disease defense barrier for crops.

[0005] Although there are some oxadiazine-related products on the market, there are still many problems to be overcome in the existing preparation process. After the existing oxadiazine-related products are put into water, the agent cannot be quickly and evenly dispersed to form a stable suspension, but agglomerates and settles at the bottom of the water for a long time, causing the nozzle to be blocked during spraying, uneven spraying, and ultimately uneven drug treatment of different parts of the crop, affecting the prevention and control effect; and after long-term use, the tolerance of pathogens to oxadiazine-related products increases rapidly, and the originally recommended dosage gradually becomes ineffective. Farmers have to increase the dosage of the drug, which not only increases costs, but also aggravates the problems of pesticide residues and environmental pollution.

[0006] Therefore, we proposed a water-dispersible granule of thiamethoxam, which has the advantages of rapid and uniform dispersion, high suspension rate, ability to delay drug resistance and safety to crops, and a preparation process. Summary of the invention

[0007] In view of the shortcomings of the prior art, the present invention aims to provide azomethasone water dispersible granules and a preparation process.

[0008] A preparation process of azoxazone water dispersible granules comprises the following steps: S1: Modified tungsten trioxide nanoflowers loaded with pyraclostrobin and manil Add polyethylene glycol and sodium dodecyl sulfate to an ethanol aqueous solution and then mix with an ammonium tungstate solution, adjust the pH and react to obtain tungsten trioxide nanoflowers modified with polyethylene glycol and sodium dodecyl sulfate, and then load pyraclostrobin and methoconazole on the tungsten trioxide nanoflowers modified with polyethylene glycol and sodium dodecyl sulfate to obtain tungsten trioxide nanoflowers loaded with pyraclostrobin and methoconazole; S2: Flexibility of microcapsules of tungsten trioxide nanoflowers loaded with pyraclostrobin and methanamide Microcapsule flexible particles were prepared by using octylphenol polyoxyethylene ether OP-10, sodium lignin sulfonate, dibutyltin dilaurate and deionized water as aqueous phase solution, and tungsten trioxide nanoflowers loaded with pyraclostrobin and methotrione, 4,4-diphenylmethane diisocyanate and 150# solvent oil as oil phase solution. S3: Preparation of polymer binder Chitosan is modified to obtain carboxymethyl chitosan, and then glucuronic acid and polyvinyl alcohol are grafted onto the carboxymethyl chitosan to obtain a polymer binder; S4: Preparation of Nano-Aids Mesoporous organic silica nanoparticles are prepared, and then dopamine is encapsulated and loaded with apricot wood vinegar to obtain nano-adjuvants; S5: Preparation of water dispersible granules 40-50 parts by weight of microcapsule flexible particles, 10-20 parts by weight of nano additives, 2-8 parts by weight of sodium dodecyl sulfate, 5-8 parts by weight of lignin sulfonate, 20-30 parts by weight of calcium chloride, 1-2 parts by weight of isooctyl alcohol and 20-30 parts by weight of diatomaceous earth are mixed and crushed, and then kneaded and granulated with 5-8 parts by weight of polymer binder and 1-2 parts by weight of deionized water to obtain water dispersible granules.

[0009] Furthermore, step S1 modifies the modified tungsten trioxide nanoflowers loaded with pyraclostrobin and metiram, specifically comprising the following steps: S1.1: Dissolve 1-2 parts by weight of ammonium tungstate in 20-25 parts by weight of ultrapure water and stir continuously to obtain solution A; add 0.1-0.2 parts by weight of polyethylene glycol with a molecular weight of 4000 and 0.05-0.08 parts by weight of sodium lauryl sulfate to 10-12 parts by weight of ethanol aqueous solution, with a volume ratio of water to ethanol of 2-3:1; stir and mix to obtain solution B; S1.2: After mixing solution A and solution B evenly, add hydrochloric acid to adjust the pH to 1-1.2, add the adjusted mixed solution into the reactor, and then react at 160-170°C for 10-12h. After the reaction is completed, centrifuge and filter to obtain a precipitate. Wash the precipitate with ultrapure water for 2-3 times, and finally, freeze-dry to obtain tungsten trioxide nanoflowers modified with polyethylene glycol and sodium dodecyl sulfate. S1.3: Mix 4-5 parts by weight of pyraclostrobin and 50-60 parts by weight of methocarb, add them into 100-120 parts by weight of toluene, then add 1-2 parts by weight of sodium dodecyl sulfate, stir and mix evenly to obtain a raw drug mixture, then add polyethylene glycol and sodium dodecyl sulfate modified tungsten trioxide nanoflowers to the raw drug mixture, and ultrasonically treat for 20-30 minutes, place at 4-5°C for 10-12 hours to obtain a precipitate, then wash and freeze-dry to obtain tungsten trioxide nanoflowers loaded with pyraclostrobin and methocarb.

[0010] Furthermore, step S2 is to make the microcapsules of tungsten trioxide nanoflowers loaded with pyraclostrobin and methanamide flexible, which specifically includes the following steps: S2.1: Add 1-2 parts by weight of octylphenol polyoxyethylene ether OP-10, 2-3 parts by weight of sodium lignin sulfonate and 0.1-0.2 parts by weight of dibutyltin dilaurate to 60-65 parts by weight of deionized water, stir and mix well to obtain an aqueous solution; S2.2: Add 9-10 parts by weight of tungsten trioxide nanoflowers loaded with pyraclostrobin and methanamide and 1.5-1.8 parts by weight of 4,4-diphenylmethane diisocyanate to 18-20 parts by weight of 150# solvent oil, stir and mix to obtain an oil phase solution; S2.3: At room temperature, the oil phase solution is injected into the water phase solution, followed by homogenization and shearing at 1000-1200 r / min for 5-10 min to obtain an emulsion, the emulsion is kept in a water bath at 70-75°C for 2-3 h, during which time it is stirred at 300-400 r / min to obtain a mixed emulsion, the mixed emulsion is spray-dried to obtain microcapsule flexible particles.

[0011] Furthermore, the preparation of the polymer binder in step S3 specifically includes the following steps: S3.1: Weigh 2-3 parts by weight of chitosan, add to 50-60 parts by weight of isopropanol, swell for 1-2 hours, then add 1-2 parts by weight of 10-12wt% sodium hydroxide aqueous solution, react for 1-2 hours, then add 6-9 parts by weight of 20-30wt% chloroacetic acid aqueous solution and react at 60-62°C. After the reaction, wash with ethanol, add 5-8 parts by weight of hydrochloric acid to neutrality and continue to react for 2-3 hours. After the reaction, wash with ethanol again to neutrality, and obtain carboxymethyl chitosan by freeze drying; S3.2: Dissolve 5-8 parts by weight of carboxymethyl chitosan in 20-30 parts by weight of deionized water, stir and mix to obtain a carboxymethyl chitosan solution, then dissolve 2-3 parts by weight of glucuronic acid in 10-12 parts by weight of deionized water, stir and mix, add 1-2 parts by weight of N, N'-dicyclohexylcarbodiimide, stir for 5-8h, and obtain a glucuronic acid solution; S3.3: Add the glucuronic acid solution dropwise to the carboxymethyl chitosan solution, and stir and mix continuously for 10-12 hours. After the reaction is completed, use tetrahydrofuran to separate the phases, remove the lower layer, wash and dry, and obtain glucuronic acid grafted carboxymethyl chitosan; S3.4: Dissolve the glucuronic acid grafted carboxymethyl chitosan in 10-12 parts by weight of dimethyl sulfoxide solution at 40-45°C, stir and mix, add 3-5 parts by weight of 40-50wt% polyvinyl alcohol aqueous solution, then add 0.05-0.08 parts by weight of ammonium persulfate, stir and mix, and then graft react at 50-60°C for 2-3h. After the reaction, dialyze and purify the product and dry it to obtain a polymer binder.

[0012] Furthermore, the preparation of the nano-additive in step S4 specifically comprises the following steps: S4.1: Add 0.4-0.8 parts by weight of triethanolamine to 120-150 parts by weight of deionized water, and perform ultrasonic dispersion for 20-30 minutes, and then stir and mix at 75-80° C. for 20-30 minutes, and then add 1.5-2 parts by weight of hexadecyltrimethylammonium bromide, and continue stirring for 1-2 hours, and finally add 10-12 parts by weight of tetraethyl orthosilicate and 9-10 parts by weight of bis[3-(triethoxysilyl)propyl]tetrasulfide, and stir and mix at 75-80° C. for 10-12 hours to obtain a reaction system; S4.2: The reaction system is centrifuged at 11000-12000 r / min to obtain a precipitate, which is washed with anhydrous ethanol for 2-3 times, and then washed with an acidic ethanol solution at 60-62° C. for 10-12 h. The product is collected by centrifugation again and washed with anhydrous ethanol for three times. After centrifugation, the solid is placed in a vacuum drying oven and dried for 10-12 h to obtain mesoporous organic silica nanoparticles; S4.3: Disperse 1-2 parts by weight of mesoporous organic silica nanoparticles in 250-300 parts by weight of Tris-HCl buffer with a pH of 8.5, ultrasonically disperse for 20-30 minutes, and then stir for 20-30 minutes. Then add 0.5-1 parts by weight of dopamine hydrochloride solid powder, stir and mix for 8-10 hours, then add 1-2 parts by weight of apricot wood vinegar, stir and mix for 10-12 hours, and centrifuge at 11000-12000r / min. Wash the precipitate with deionized water 2-3 times, and then wash with ethanol 1-2 times, and obtain the nano-additive after vacuum drying.

[0013] Furthermore, the preparation of the water dispersible granules in step S5 specifically comprises the following steps: S5.1: 40-50 parts by weight of microcapsule flexible particles, 10-20 parts by weight of nano additives, 2-8 parts by weight of sodium lauryl sulfate, 5-8 parts by weight of lignin sulfonate, 20-30 parts by weight of calcium chloride, 1-2 parts by weight of isooctyl alcohol and 20-30 parts by weight of diatomaceous earth are mixed to obtain a mixture; S5.2: The mixture is ultrafinely ground by a jet mill to obtain a mother powder. The mother powder, 5-8 parts by weight of a polymer binder and 1-2 parts by weight of deionized water are placed in a kneader and kneaded, and then passed into an extrusion granulator for granulation to obtain water-dispersible granules.

[0014] Furthermore, the volume ratio of hydrochloric acid to anhydrous ethanol in the acidic ethanol solution in step S4.2 is 4-5:95-96.

[0015] A trifloxystrobin water dispersible granule is prepared by any one of the above-mentioned processes for preparing a trifloxystrobin water dispersible granule.

[0016] Compared with the prior art, the present invention has at least the following beneficial effects: 1. The present invention uses tungsten trioxide nanoflowers to load pyraclostrobin and metiram. Tungsten trioxide nanoflowers have unique optical properties, can absorb and scatter ultraviolet rays and other light, reduce the direct irradiation of light on pyraclostrobin and metiram, thereby reducing its decomposition and failure caused by photolysis, and prolonging the validity period and duration of the pesticide. The special structure of tungsten trioxide nanoflowers can play a sustained release role for pyraclostrobin and metiram. After modification with polyethylene glycol and sodium dodecyl sulfate, the sustained release rate of pyraclostrobin and metiram can be adjusted, so that the pesticide can continue to exert its efficacy on the surface of crops, and the slow release avoids a one-time high dose of the drug. The agent acts on pathogens, reducing the chance of pathogens developing drug resistance due to sudden high-concentration drug stimulation, thereby delaying drug resistance. At the same time, polyethylene glycol is a polymer with good water solubility and sodium dodecyl sulfate is an anionic surfactant. After being modified by the two, polyethylene glycol can prevent the agglomeration of particles because its molecular chain has a certain steric hindrance effect, which enables the particles to maintain a good dispersion state in water. Sodium dodecyl sulfate can improve the wettability of the particles, so that the prepared water-dispersible granules can be quickly soaked and dispersed by water after contacting water, avoiding the phenomenon of particle agglomeration.

[0017] 2. During the formation of the flexible microcapsule particles of the present invention, 4,4-diphenylmethane diisocyanate can interact with the components in the aqueous solution to form a layer of microcapsule wall on the surface of the tungsten trioxide nanoflower loaded with pyraclostrobin and methanamide, thereby further controlling the release of the active ingredient. The octylphenol polyoxyethylene ether molecules occupy the capsule interface and prevent the excessive aggregation of the 4,4-diphenylmethane diisocyanate capsule shell material through "steric hindrance". The octylphenol polyoxyethylene ether covers the chain end of the capsule shell, which limits the further thickening of the capsule shell, reduces the thickness of the capsule shell, and makes the prepared flexible microcapsule structure When contacting the leaf surface, it can better adapt to the microscopic uneven surface of the leaf surface, achieve high-efficiency deformation fit, and increase the contact area and fit between the microcapsule flexible particles and the leaf surface. The high-efficiency deformation fit and adhesion retention of the microcapsule flexible particles and the leaf surface ensure that the agent can continue to play a role on the leaf surface in the main area where pests are active. Since the agent can be released continuously, for some pests with a tendency to develop drug resistance, the continuous low-dose drug effect can effectively inhibit their growth and reproduction, reduce their chances of developing drug resistance, and also improve the prevention and control effect of pests.

[0018] 3. The polymer binder formed by grafting carboxymethyl chitosan with glucuronic acid and then reacting with polyvinyl alcohol through a grafting reaction has abundant functional groups and a good molecular chain structure. The molecular chains of the polymer binder can interact with each other through hydrogen bonds, van der Waals forces, etc., so that various components in the water-dispersible granules are tightly bonded together, which is beneficial to the molding of the granules, and the granules have good mechanical strength and are not easy to break during storage and transportation. At the same time, both the glucuronic acid-grafted carboxymethyl chitosan and polyvinyl alcohol contain abundant hydrophilic functional groups, which can reduce the surface tension between the water-dispersible granules and water, and improve the wettability of the water-dispersible granules. The good wettability enables the water-dispersible granules to be quickly soaked by water after contacting water. The polymer binder formed by the grafting reaction has a long molecular chain, and these molecular chains will produce a steric hindrance effect around the particles. When the particles are in water, the steric hindrance of the molecular chain can prevent the particles from agglomerating due to being close to each other, thereby achieving rapid dispersion, so that the water-dispersible granules can be quickly and evenly dispersed to form a stable suspension.

[0019] 4. The nano-additive prepared by the present invention has a large specific surface area and a suitable pore structure. In the water-dispersible granules, the nano-particles can be adsorbed on the surface of the microcapsule flexible particles to prevent the agglomeration of the microcapsule flexible particles. At the same time, the presence of the nano-additive can increase the distance between the microcapsule flexible particles, making the microcapsule flexible particles easier to disperse in water. The addition of dopamine hydrochloride and apricot wood vinegar in the nano-additive gives the nano-particles good adsorption properties. Dopamine hydrochloride forms a polydopamine layer on the surface of the nano-particles. Polydopamine has a strong adhesion When the water-dispersible granules are sprayed onto the surface of plants, the nano-additives can help the microcapsule flexible particles to better adsorb on the surface of plants. The enhanced adsorption and adhesion properties can reduce the loss of pesticides caused by rain erosion, wind blowing and other factors, so that the pesticides can continue to exert their efficacy on the surface of plants. In addition, the loaded apricot wood vinegar has certain antibacterial and insect repellent effects. When it acts on pests together with the active ingredients of pyraclostrobin and metiram, a multi-target mode of action is formed, which can enhance the control effect on pests and increase the difficulty for pests to develop resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The present invention is a flow chart of the preparation process of azomethasone water dispersible granules used in an embodiment of the present invention. DETAILED DESCRIPTION

[0021] The preparation process of azomethasone water dispersible granules provided by the present invention is described in detail below with reference to the accompanying drawings and specific examples.

[0022] Example 1 A preparation process of azomethasone water dispersible granules, such as Figure 1 As shown, the following steps are included: S1: Modified tungsten trioxide nanoflowers loaded with pyraclostrobin and manil S1.1: Dissolve 1 part by weight of ammonium tungstate in 20 parts by weight of ultrapure water and stir continuously to obtain solution A; add 0.1 parts by weight of polyethylene glycol with a molecular weight of 4000 and 0.05 parts by weight of sodium dodecyl sulfate to 10 parts by weight of ethanol aqueous solution, with the volume ratio of water to ethanol being 2:1; stir and mix to obtain solution B; S1.2: After mixing solution A and solution B evenly, add hydrochloric acid to adjust the pH to 1, add the adjusted mixed solution into the reactor, and then react at 160°C for 10 hours. After the reaction is completed, centrifuge and filter to obtain a precipitate. Wash the precipitate twice with ultrapure water by centrifugation. Finally, freeze-dry to obtain tungsten trioxide nanoflowers modified with polyethylene glycol and sodium dodecyl sulfate. S1.3: 4 parts by weight of pyraclostrobin and 50 parts by weight of methocarb are mixed and added to 100 parts by weight of toluene, and then 1 part by weight of sodium dodecyl sulfate is added, and the mixture is stirred and mixed evenly to obtain a raw drug mixture, and then polyethylene glycol and sodium dodecyl sulfate modified tungsten trioxide nanoflowers are added to the raw drug mixture, and ultrasonically treated for 20 minutes, and placed at 4°C for 10 hours to obtain a precipitate, and then washed and freeze-dried to obtain tungsten trioxide nanoflowers loaded with pyraclostrobin and methocarb; S2: Flexibility of microcapsules of tungsten trioxide nanoflowers loaded with pyraclostrobin and methanamide S2.1: Add 1 part by weight of octylphenol polyoxyethylene ether OP-10, 2 parts by weight of sodium lignin sulfonate and 0.1 parts by weight of dibutyltin dilaurate to 60 parts by weight of deionized water, stir and mix well to obtain an aqueous solution; S2.2: Add 9 parts by weight of tungsten trioxide nanoflowers loaded with pyraclostrobin and methanamide and 1.5 parts by weight of 4,4-diphenylmethane diisocyanate to 18 parts by weight of 150# solvent oil, stir and mix to obtain an oil phase solution; S2.3: At room temperature, the oil phase solution is injected into the water phase solution, and then homogenized and sheared at 1000 r / min for 5 min to obtain an emulsion, the emulsion is kept in a 70°C water bath for 2 h, during which it is stirred at 300 r / min to obtain a mixed emulsion, and the mixed emulsion is spray-dried to obtain microcapsule flexible particles; S3: Preparation of polymer binder S3.1: Weigh 2 parts by weight of chitosan, add it to 50 parts by weight of isopropanol, swell for 1 hour, then add 1 part by weight of 10wt% sodium hydroxide aqueous solution, react for 1 hour, then add 6 parts by weight of 20wt% chloroacetic acid aqueous solution and react at 60°C. After the reaction, wash with ethanol, wash to neutrality, add 5 parts by weight of hydrochloric acid and continue to react for 2 hours. After the reaction, wash again with ethanol to neutrality, and obtain carboxymethyl chitosan by freeze drying; S3.2: Dissolve 5 parts by weight of carboxymethyl chitosan in 20 parts by weight of deionized water, stir and mix to obtain a carboxymethyl chitosan solution, then dissolve 2 parts by weight of glucuronic acid in 10 parts by weight of deionized water, stir and mix, add 1 part by weight of N, N'-dicyclohexylcarbodiimide, stir for 5 hours, and obtain a glucuronic acid solution; S3.3: Add the glucuronic acid solution dropwise to the carboxymethyl chitosan solution, and stir and mix continuously for 10 hours. After the reaction is completed, use tetrahydrofuran to separate the phases, remove the lower layer, wash and dry, and obtain glucuronic acid grafted carboxymethyl chitosan; S3.4: dissolving the glucuronic acid grafted carboxymethyl chitosan in 10 parts by weight of a dimethyl sulfoxide solution at 40° C., stirring and mixing, adding 3 parts by weight of a 40wt% polyvinyl alcohol aqueous solution, and then adding 0.05 parts by weight of ammonium persulfate, stirring and mixing, and performing a grafting reaction at 50° C. for 2 hours. After the reaction is completed, the product is dialyzed, purified, and dried to obtain a polymer binder; S4: Preparation of Nano-Aids S4.1: 0.4 parts by weight of triethanolamine is added to 120 parts by weight of deionized water, and ultrasonically dispersed for 20 minutes, and then stirred and mixed at 75°C for 20 minutes, and then 1.5-2 parts by weight of hexadecyltrimethylammonium bromide is added, and stirring is continued for 1 hour, and finally 10 parts by weight of tetraethyl orthosilicate and 9 parts by weight of bis[3-(triethoxysilyl)propyl]tetrasulfide are added, and stirred and mixed at 75°C for 10 hours to obtain a reaction system; S4.2: The reaction system was centrifuged at 11000 r / min to obtain a precipitate, which was washed twice with anhydrous ethanol, and then washed with an acidic ethanol solution at 60°C for 10 h, wherein the volume ratio of hydrochloric acid to anhydrous ethanol in the acidic ethanol solution was 4:96, the product was collected by centrifugation again and washed three times with anhydrous ethanol, and the solid after centrifugation was placed in a vacuum drying oven and dried for 10 h to obtain mesoporous organic silica nanoparticles; S4.3: Disperse 1 part by weight of mesoporous organic silica nanoparticles in 250 parts by weight of Tris-HCl buffer with a pH of 8.5, ultrasonically disperse for 20 minutes, and then stir for 20 minutes, then add 0.5 parts by weight of dopamine hydrochloride solid powder, stir and mix for 8 hours, then add 1 part by weight of apricot wood vinegar, stir and mix for 10 hours, and centrifuge at 11000 r / min, wash the precipitate twice with deionized water, and then wash once with ethanol, and obtain the nano-adjuvant after vacuum drying; S5: Preparation of water dispersible granules S5.1: 40 parts by weight of microcapsule flexible particles, 10 parts by weight of nano additives, 2 parts by weight of sodium lauryl sulfate, 5 parts by weight of lignin sulfonate, 20 parts by weight of calcium chloride, 1 part by weight of isooctyl alcohol and 20 parts by weight of diatomaceous earth are mixed to obtain a mixture; S5.2: The mixture is ultrafinely ground by a jet mill to obtain a mother powder. The mother powder, 5 parts by weight of a polymer binder and 1 part by weight of deionized water are placed in a kneader and kneaded, and then passed into an extrusion granulator for granulation to obtain water-dispersible granules.

[0023] Example 2 A preparation process of azomethasone water dispersible granules, such as Figure 1 As shown, the following steps are included: S1: Modified tungsten trioxide nanoflowers loaded with pyraclostrobin and manil S1.1: 2 parts by weight of ammonium tungstate are dissolved in 25 parts by weight of ultrapure water and stirred continuously to obtain solution A; 0.2 parts by weight of polyethylene glycol with a molecular weight of 4000 and 0.08 parts by weight of sodium dodecyl sulfate are added to 12 parts by weight of ethanol aqueous solution, the volume ratio of water to ethanol being 3:1, and solution B is obtained after stirring and mixing; S1.2: After mixing solution A and solution B evenly, add hydrochloric acid to adjust the pH to 1.2, add the adjusted mixed solution into the reactor, and then react at 160°C for 10 hours. After the reaction is completed, centrifuge and filter to obtain a precipitate. Wash the precipitate twice with ultrapure water, and finally, freeze-dry to obtain tungsten trioxide nanoflowers modified with polyethylene glycol and sodium dodecyl sulfate. S1.3: Mix 5 parts by weight of pyraclostrobin and 60 parts by weight of methocarb, add them to 120 parts by weight of toluene, then add 2 parts by weight of sodium dodecyl sulfate, stir and mix evenly to obtain a raw drug mixture, then add polyethylene glycol and sodium dodecyl sulfate modified tungsten trioxide nanoflowers to the raw drug mixture, and ultrasonically treat for 20 minutes, place at 4°C for 10 hours to obtain a precipitate, then wash and freeze-dry to obtain tungsten trioxide nanoflowers loaded with pyraclostrobin and methocarb; S2: Flexibility of microcapsules of tungsten trioxide nanoflowers loaded with pyraclostrobin and methanamide S2.1: Add 2 parts by weight of octylphenol polyoxyethylene ether OP-10, 3 parts by weight of sodium lignin sulfonate and 0.2 parts by weight of dibutyltin dilaurate to 65 parts by weight of deionized water, stir and mix well to obtain an aqueous solution; S2.2: Add 10 parts by weight of tungsten trioxide nanoflowers loaded with pyraclostrobin and methanamide and 1.8 parts by weight of 4,4-diphenylmethane diisocyanate to 20 parts by weight of 150# solvent oil, stir and mix to obtain an oil phase solution; S2.3: At room temperature, the oil phase solution is injected into the water phase solution, and then homogenized and sheared at 1000 r / min for 5 min to obtain an emulsion, the emulsion is kept in a 70°C water bath for 2 h, during which it is stirred at 300 r / min to obtain a mixed emulsion, and the mixed emulsion is spray-dried to obtain microcapsule flexible particles; S3: Preparation of polymer binder S3.1: Weigh 3 parts by weight of chitosan, add it to 60 parts by weight of isopropanol, swell for 1 hour, then add 2 parts by weight of 12wt% sodium hydroxide aqueous solution, react for 1 hour, then add 9 parts by weight of 30wt% chloroacetic acid aqueous solution and react at 60°C. After the reaction, wash with ethanol, wash to neutrality, add 8 parts by weight of hydrochloric acid and continue to react for 2 hours. After the reaction, wash again with ethanol to neutrality, and obtain carboxymethyl chitosan by freeze drying; S3.2: 8 parts by weight of carboxymethyl chitosan are dissolved in 30 parts by weight of deionized water, and the mixture is stirred to obtain a carboxymethyl chitosan solution. Then, 3 parts by weight of glucuronic acid are dissolved in 12 parts by weight of deionized water, and the mixture is stirred to obtain 2 parts by weight of N, N'-dicyclohexylcarbodiimide, and the mixture is stirred for 5 hours to obtain a glucuronic acid solution. S3.3: Add the glucuronic acid solution dropwise to the carboxymethyl chitosan solution, and stir and mix continuously for 10 hours. After the reaction is completed, use tetrahydrofuran to separate the phases, remove the lower layer, wash and dry, and obtain glucuronic acid grafted carboxymethyl chitosan; S3.4: dissolving glucuronic acid grafted carboxymethyl chitosan in 12 parts by weight of dimethyl sulfoxide solution at 40° C., stirring and mixing, adding 5 parts by weight of 50wt% polyvinyl alcohol aqueous solution, and then adding 0.08 parts by weight of ammonium persulfate, stirring and mixing, and performing grafting reaction at 50° C. for 2 hours. After the reaction is completed, the product is dialyzed, purified and dried to obtain a polymer binder; S4: Preparation of Nano-Aids S4.1: 0.8 parts by weight of triethanolamine was added to 150 parts by weight of deionized water, and ultrasonic dispersion was performed for 20 minutes, followed by stirring and mixing at 75° C. for 20 minutes, and then 2 parts by weight of hexadecyltrimethylammonium bromide were added, and stirring was continued for 1 hour, and finally 12 parts by weight of tetraethyl orthosilicate and 10 parts by weight of bis[3-(triethoxysilyl)propyl]tetrasulfide were added, and stirring and mixing was performed at 75° C. for 10 hours to obtain a reaction system; S4.2: The reaction system was centrifuged at 11000 r / min to obtain a precipitate, which was washed twice with anhydrous ethanol, and then washed with an acidic ethanol solution at 60°C for 10 h, wherein the volume ratio of hydrochloric acid to anhydrous ethanol in the acidic ethanol solution was 5:95, the product was collected by centrifugation again and washed three times with anhydrous ethanol, and the solid after centrifugation was placed in a vacuum drying oven and dried for 10 h to obtain mesoporous organic silica nanoparticles; S4.3: Disperse 2 parts by weight of mesoporous organic silica nanoparticles in 300 parts by weight of Tris-HCl buffer with a pH of 8.5, ultrasonically disperse for 20 minutes, and then stir for 20 minutes, then add 1 part by weight of dopamine hydrochloride solid powder, stir and mix for 8 hours, then add 2 parts by weight of apricot wood vinegar, stir and mix for 10 hours, and centrifuge at 11000r / min, wash the precipitate twice with deionized water, and then wash once with ethanol, and obtain the nano-adjuvant after vacuum drying; S5: Preparation of water dispersible granules S5.1: 50 parts by weight of microcapsule flexible particles, 20 parts by weight of nano additives, 8 parts by weight of sodium lauryl sulfate, 8 parts by weight of lignin sulfonate, 30 parts by weight of calcium chloride, 2 parts by weight of isooctyl alcohol and 30 parts by weight of diatomaceous earth are mixed to obtain a mixture; S5.2: The mixture is ultrafinely ground by a jet mill to obtain a mother powder. The mother powder, 8 parts by weight of a polymer binder and 2 parts by weight of deionized water are placed in a kneader and kneaded, and then passed into an extrusion granulator for granulation to obtain water-dispersible granules.

[0024] Example 3 A preparation process of azomethasone water dispersible granules, such as Figure 1 As shown, the following steps are included: S1: Modified tungsten trioxide nanoflowers loaded with pyraclostrobin and manil S1.1: Dissolve 1 part by weight of ammonium tungstate in 20 parts by weight of ultrapure water and stir continuously to obtain solution A; add 0.1 parts by weight of polyethylene glycol with a molecular weight of 4000 and 0.05 parts by weight of sodium dodecyl sulfate to 10 parts by weight of ethanol aqueous solution, with the volume ratio of water to ethanol being 2:1; stir and mix to obtain solution B; S1.2: After mixing solution A and solution B evenly, add hydrochloric acid to adjust the pH to 1, add the adjusted mixed solution into the reactor, and then react at 170°C for 12 hours. After the reaction is completed, centrifuge and filter to obtain a precipitate. Wash the precipitate with ultrapure water for 3 times, and finally, freeze-dry to obtain tungsten trioxide nanoflowers modified with polyethylene glycol and sodium dodecyl sulfate; S1.3: 4 parts by weight of pyraclostrobin and 50 parts by weight of methocarb are mixed and added to 100 parts by weight of toluene, and then 1 part by weight of sodium dodecyl sulfate is added, and the mixture is stirred and mixed evenly to obtain a raw drug mixture, and then polyethylene glycol and sodium dodecyl sulfate modified tungsten trioxide nanoflowers are added to the raw drug mixture, and ultrasonic treatment is performed for 30 minutes, and the mixture is placed at 5°C for 12 hours to obtain a precipitate, and then washed and freeze-dried to obtain tungsten trioxide nanoflowers loaded with pyraclostrobin and methocarb; S2: Flexibility of microcapsules of tungsten trioxide nanoflowers loaded with pyraclostrobin and methanamide S2.1: Add 1 part by weight of octylphenol polyoxyethylene ether OP-10, 2 parts by weight of sodium lignin sulfonate and 0.1 parts by weight of dibutyltin dilaurate to 60 parts by weight of deionized water, stir and mix well to obtain an aqueous solution; S2.2: Add 9 parts by weight of tungsten trioxide nanoflowers loaded with pyraclostrobin and methanamide and 1.5 parts by weight of 4,4-diphenylmethane diisocyanate to 18 parts by weight of 150# solvent oil, stir and mix to obtain an oil phase solution; S2.3: At room temperature, the oil phase solution is injected into the water phase solution, and then homogenized and sheared at 1200 r / min for 10 min to obtain an emulsion, the emulsion is kept in a 75°C water bath for 3 h, during which it is stirred at 400 r / min to obtain a mixed emulsion, and the mixed emulsion is spray-dried to obtain microcapsule flexible particles; S3: Preparation of polymer binder S3.1: Weigh 2 parts by weight of chitosan, add it to 50 parts by weight of isopropanol, swell for 2 hours, then add 1 part by weight of 10wt% sodium hydroxide aqueous solution, react for 2 hours, then add 6 parts by weight of 20wt% chloroacetic acid aqueous solution and react at 62°C. After the reaction, wash with ethanol, wash to neutrality, add 5 parts by weight of hydrochloric acid and continue to react for 3 hours. After the reaction, wash with ethanol again to neutrality, and obtain carboxymethyl chitosan by freeze drying; S3.2: Dissolve 5 parts by weight of carboxymethyl chitosan in 20 parts by weight of deionized water, stir and mix to obtain a carboxymethyl chitosan solution, then dissolve 2 parts by weight of glucuronic acid in 10 parts by weight of deionized water, stir and mix, add 1 part by weight of N, N'-dicyclohexylcarbodiimide, stir for 8 hours, and obtain a glucuronic acid solution; S3.3: Add the glucuronic acid solution dropwise to the carboxymethyl chitosan solution, and stir and mix continuously for 12 hours. After the reaction is completed, use tetrahydrofuran to separate the phases, remove the lower layer, wash and dry, and obtain glucuronic acid grafted carboxymethyl chitosan; S3.4: dissolving the glucuronic acid grafted carboxymethyl chitosan in 10 parts by weight of a dimethyl sulfoxide solution at 45° C., stirring and mixing, adding 3 parts by weight of a 40wt% polyvinyl alcohol aqueous solution, and then adding 0.05 parts by weight of ammonium persulfate, stirring and mixing, and then grafting reaction at 60° C. for 3 hours. After the reaction is completed, the product is dialyzed, purified, and dried to obtain a polymer binder; S4: Preparation of Nano-Aids S4.1: 0.4 parts by weight of triethanolamine was added to 120 parts by weight of deionized water, and ultrasonic dispersion was performed for 30 minutes, followed by stirring and mixing at 80° C. for 30 minutes, and then 1.5 parts by weight of hexadecyltrimethylammonium bromide was added, and stirring was continued for 2 hours, and finally 10 parts by weight of tetraethyl orthosilicate and 9 parts by weight of bis[3-(triethoxysilyl)propyl]tetrasulfide were added, and stirring and mixing was performed at 80° C. for 12 hours to obtain a reaction system; S4.2: The reaction system was centrifuged at 12000 r / min to obtain a precipitate, which was washed with anhydrous ethanol three times, and then washed with an acidic ethanol solution at 62°C for 12 h, wherein the volume ratio of hydrochloric acid to anhydrous ethanol in the acidic ethanol solution was 4:96, and the product was collected by centrifugation again and washed with anhydrous ethanol three times. After centrifugation, the solid was placed in a vacuum drying oven and dried for 12 h to obtain mesoporous organic silica nanoparticles; S4.3: Disperse 1 part by weight of mesoporous organic silica nanoparticles in 250 parts by weight of Tris-HCl buffer with a pH of 8.5, ultrasonically disperse for 30 minutes, and then stir for 30 minutes, then add 0.5 parts by weight of dopamine hydrochloride solid powder, stir and mix for 10 hours, then add 1 part by weight of apricot wood vinegar, stir and mix for 12 hours, and centrifuge at 12000 r / min, wash the precipitate with deionized water 3 times, and then wash with ethanol 2 times, and obtain the nano-adjuvant after vacuum drying; S5: Preparation of water dispersible granules S5.1: 40 parts by weight of microcapsule flexible particles, 10 parts by weight of nano additives, 2 parts by weight of sodium lauryl sulfate, 5 parts by weight of lignin sulfonate, 20 parts by weight of calcium chloride, 1 part by weight of isooctyl alcohol and 20 parts by weight of diatomaceous earth are mixed to obtain a mixture; S5.2: The mixture is ultrafinely ground by a jet mill to obtain a mother powder. The mother powder, 5 parts by weight of a polymer binder and 1 part by weight of deionized water are placed in a kneader and kneaded, and then passed into an extrusion granulator for granulation to obtain water-dispersible granules.

[0025] Comparative Example 1 Compared with Example 1, the difference of Comparative Example 1 is that Comparative Example 1 removes step S1, replaces the tungsten trioxide nanoflowers loaded with pyraclostrobin and manicotamide in step S2.2 with a mixture of 4 parts by weight of pyraclostrobin and 50 parts by weight of manicotamide, and the other steps remain unchanged to prepare water dispersible granules, which is recorded as Comparative Example 1.

[0026] Comparative Example 2 Compared with Example 1, the difference of Comparative Example 2 is that the polyethylene glycol in step S1.1 is removed in Comparative Example 2, and the other steps remain unchanged to prepare the water dispersible granules, which is recorded as Comparative Example 2.

[0027] Comparative Example 3 Compared with Example 1, the difference of Comparative Example 3 is that the sodium dodecyl sulfate in step S1.1 is removed in Comparative Example 3, and the other steps are unchanged to prepare the water dispersible granules, which is recorded as Comparative Example 3.

[0028] Comparative Example 4 Compared with Example 1, the difference of Comparative Example 4 is that step S2 is removed in Comparative Example 4, and the microcapsule flexible particles in step S5.1 are replaced with tungsten trioxide nanoflowers loaded with pyraclostrobin and methocarb in equal weight parts, and the other steps are unchanged to prepare water dispersible granules, which is recorded as Comparative Example 4.

[0029] Comparative Example 5 Compared with Example 1, the difference of Comparative Example 5 is that Comparative Example 5 removes steps S3.2 and S3.3, replaces the glucuronic acid grafted carboxymethyl chitosan in step S3.4 with an equal weight portion of carboxymethyl chitosan, and prepares water dispersible granules without changing the other steps, which is recorded as Comparative Example 5.

[0030] Comparative Example 6 Compared with Example 1, the difference of Comparative Example 6 is that step S3.4 is removed in Comparative Example 6, and the glucuronic acid grafted carboxymethyl chitosan prepared in step S3.3 is the polymer binder, and the remaining steps are unchanged to prepare the water dispersible granules, which is recorded as Comparative Example 6.

[0031] Comparative Example 7 Compared with Example 1, the difference of Comparative Example 7 is that the nano-auxiliary agent in steps S4 and 5.1 is removed in Comparative Example 7, and the remaining steps are unchanged to prepare the water dispersible granules, which is recorded as Comparative Example 7.

[0032] The suspension rate and wetting time of Examples 1-3 and Comparative Examples 1-3 and 5-7 were measured, and the measurement results are shown in Table 1. Suspension rate: CB / T14825-2006; Wetting time: CB / T5451-2001.

[0033] Table 1. Suspension rate and wetting time measurement results of Examples 1-3 and Comparative Examples 1-3, 5-7

[0034] From the data in Table 1, it can be seen that the suspension rates and wetting times of Comparative Examples 1, 2 and 3 are poorer than those of the embodiment, and Comparative Examples 2 and 3 are better than Comparative Example 1, indicating that after being modified by polyethylene glycol and sodium dodecyl sulfate, a synergistic effect can be produced. On the one hand, the particles can maintain a good dispersion state in water, and on the other hand, the wettability of the particles can be improved. The interaction between the two enables the prepared water-dispersible granules to be quickly soaked and dispersed by water after contacting water, avoiding the phenomenon of particle agglomeration; from the data of Comparative Examples 5 and 6, it can be seen that the polymer binder formed by grafting carboxymethyl chitosan with glucuronic acid and then reacting with polyvinyl alcohol through a grafting reaction improves the wettability of the water-dispersible granules, and enables the water-dispersible granules to be quickly and evenly dispersed to form a stable suspension; from the data of Comparative Example 7, it can be seen that the nano-additive can also improve the suspension of the water-dispersible granules and avoid agglomeration.

[0035] Divide the tomato planting land into 9 equal parts, each with an area of ​​100m 2 , isolate each tomato planting site to ensure that the cultivation conditions of each tomato planting site are consistent.

[0036] At the early stage of anthracnose, 8 tomato planting fields were subjected to conventional stem and leaf spray treatment using the water-dispersible granules prepared in Examples 1-3, Comparative Examples 1-4 and Comparative Example 7. The 8 tomato planting fields were marked as 1, 2, 3, 3, 5, 6, 7 and 8 in sequence. The disease index surveyed one day before the conventional stem and leaf spray treatment was the initial disease index. The first prevention efficacy survey was conducted 7 days after the conventional stem and leaf spray treatment. The second prevention efficacy survey was conducted 14 days after the conventional stem and leaf spray treatment. The third prevention efficacy survey was conducted 21 days after the conventional stem and leaf spray treatment. The fourth prevention efficacy survey was conducted 30 days after the conventional stem and leaf spray treatment.

[0037] The dosage of the conventional stem and leaf spray treatment is 25g / mu, and it needs to be diluted 1000 times with water before use.

[0038] Four random survey points were taken in each tomato planting site, with two plants at each point, and all leaves of each plant were surveyed.

[0039] The ninth tomato planting site was used as a blank control and no pesticide was sprayed.

[0040] Classification method for prevention effectiveness investigation: (based on leaves) Level 0: no disease; Level 1: The lesion area accounts for less than 5% of the entire leaf area; Level 3: The lesion area accounts for less than 6-10% of the entire leaf area; Level 5: The lesion area accounts for less than 11-25% of the entire leaf area; Level 7: The lesion area accounts for less than 26-50% of the entire leaf area; Level 9: The lesion area accounts for more than 50% of the entire leaf area; The calculation formula for the prevention and control survey results is: Disease index = {[∑(number of diseased leaves at each level × corresponding level value)] / total number of leaves investigated × 9} × 100; Control effect (%) = [1-(disease index of blank control area before application × disease index of treated area after application) / (disease index of blank control area after application × disease index of treated area before application)] × 100; The results of the prevention and control survey are shown in Table 2.

[0041] Table 2. Prevention and control survey results

[0042] From the data in Table 2, it can be seen that the water-dispersible granules prepared in Examples 1-3 have significant bactericidal effects, and still have significant bactericidal effects after 30 days, indicating that the water-dispersible granules prepared in the present invention have a long-lasting sustained release effect, and can slow down drug resistance, so that the water-dispersible granules can be used for a long time to kill bacteria. From the data in No. 4-6, it can be seen that the water-dispersible granules prepared in Comparative Examples 1-3 have a poorer effect than those in the examples, because the special structure of tungsten trioxide nanoflowers can play a sustained release role on pyraclostrobin and methanamide, and at the same time, polyethylene glycol and dodecyl sulfoxide After modification with sodium pyraclostrobin, the sustained-release rate of pyraclostrobin and metiram can be adjusted, so that the water-dispersible granules can continue to exert their efficacy on the surface of crops. From the data of Site 7, it can be seen that the water-dispersible granules prepared in Comparative Example 4 are inferior to those in Example 1, indicating that the prepared flexible microcapsule structure ensures that the agent can continue to exert its effect on the leaf surface, the main area of ​​activity of harmful organisms, thereby improving the control effect on harmful organisms. From the data of Site 8, it can be seen that the water-dispersible granules prepared in Comparative Example 7 are slightly inferior to those in Example 1, indicating that nano-adjuvants can enhance the control effect on harmful organisms.

[0043] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A preparation process of azoxazone water dispersible granules, characterized in that: The steps include: S1: Modified tungsten trioxide nanoflowers loaded with pyraclostrobin and manil Add polyethylene glycol and sodium dodecyl sulfate to an ethanol aqueous solution and then mix with an ammonium tungstate solution, adjust the pH and react to obtain tungsten trioxide nanoflowers modified with polyethylene glycol and sodium dodecyl sulfate, and then load pyraclostrobin and methoconazole on the tungsten trioxide nanoflowers modified with polyethylene glycol and sodium dodecyl sulfate to obtain tungsten trioxide nanoflowers loaded with pyraclostrobin and methoconazole; S2: Flexibility of microcapsules of tungsten trioxide nanoflowers loaded with pyraclostrobin and methanamide Microcapsule flexible particles were prepared by using octylphenol polyoxyethylene ether OP-10, sodium lignin sulfonate, dibutyltin dilaurate and deionized water as aqueous phase solution, and tungsten trioxide nanoflowers loaded with pyraclostrobin and methotrione, 4,4-diphenylmethane diisocyanate and 150# solvent oil as oil phase solution. S3: Preparation of polymer binder Chitosan is modified to obtain carboxymethyl chitosan, and then glucuronic acid and polyvinyl alcohol are grafted onto the carboxymethyl chitosan to obtain a polymer binder; S4: Preparation of Nano-Aids Mesoporous organic silica nanoparticles are prepared, and then dopamine is encapsulated and loaded with apricot wood vinegar to obtain nano-adjuvants; S5: Preparation of water dispersible granules 40-50 parts by weight of microcapsule flexible particles, 10-20 parts by weight of nano additives, 2-8 parts by weight of sodium dodecyl sulfate, 5-8 parts by weight of lignin sulfonate, 20-30 parts by weight of calcium chloride, 1-2 parts by weight of isooctyl alcohol and 20-30 parts by weight of diatomaceous earth are mixed and crushed, and then kneaded and granulated with 5-8 parts by weight of polymer binder and 1-2 parts by weight of deionized water to obtain water dispersible granules.

2. The preparation process of azomethasone water dispersible granules according to claim 1, characterized in that: Step S1: Modify the modified tungsten trioxide nanoflowers to load pyraclostrobin and metiram, specifically including the following steps: S1.1: Dissolve 1-2 parts by weight of ammonium tungstate in 20-25 parts by weight of ultrapure water and stir continuously to obtain solution A; add 0.1-0.2 parts by weight of polyethylene glycol with a molecular weight of 4000 and 0.05-0.08 parts by weight of sodium lauryl sulfate to 10-12 parts by weight of ethanol aqueous solution, with a volume ratio of water to ethanol of 2-3:1; stir and mix to obtain solution B; S1.2: After mixing solution A and solution B evenly, add hydrochloric acid to adjust the pH to 1-1.2, add the adjusted mixed solution into the reactor, and then react at 160-170°C for 10-12h. After the reaction is completed, centrifuge and filter to obtain a precipitate. Wash the precipitate with ultrapure water for 2-3 times, and finally, freeze-dry to obtain tungsten trioxide nanoflowers modified with polyethylene glycol and sodium dodecyl sulfate. S1.3: Mix 4-5 parts by weight of pyraclostrobin and 50-60 parts by weight of methocarb, add them into 100-120 parts by weight of toluene, then add 1-2 parts by weight of sodium dodecyl sulfate, stir and mix evenly to obtain a raw drug mixture, then add polyethylene glycol and sodium dodecyl sulfate modified tungsten trioxide nanoflowers to the raw drug mixture, and ultrasonically treat for 20-30 minutes, place at 4-5°C for 10-12 hours to obtain a precipitate, then wash and freeze-dry to obtain tungsten trioxide nanoflowers loaded with pyraclostrobin and methocarb.

3. The preparation process of azomethasone water dispersible granules according to claim 2, characterized in that: Step S2: making the microcapsules of tungsten trioxide nanoflowers loaded with pyraclostrobin and methanamide flexible, specifically comprising the following steps: S2.1: Add 1-2 parts by weight of octylphenol polyoxyethylene ether OP-10, 2-3 parts by weight of sodium lignin sulfonate and 0.1-0.2 parts by weight of dibutyltin dilaurate to 60-65 parts by weight of deionized water, stir and mix well to obtain an aqueous solution; S2.2: Add 9-10 parts by weight of tungsten trioxide nanoflowers loaded with pyraclostrobin and methanamide and 1.5-1.8 parts by weight of 4,4-diphenylmethane diisocyanate to 18-20 parts by weight of 150# solvent oil, stir and mix to obtain an oil phase solution; S2.3: At room temperature, the oil phase solution is injected into the water phase solution, followed by homogenization and shearing at 1000-1200 r / min for 5-10 min to obtain an emulsion, the emulsion is kept in a water bath at 70-75°C for 2-3 h, during which time it is stirred at 300-400 r / min to obtain a mixed emulsion, the mixed emulsion is spray-dried to obtain microcapsule flexible particles.

4. The preparation process of azomethasone water dispersible granules according to claim 3, characterized in that: Step S3: Preparation of polymer binder, specifically comprising the following steps: S3.1: Weigh 2-3 parts by weight of chitosan, add to 50-60 parts by weight of isopropanol, swell for 1-2 hours, then add 1-2 parts by weight of 10-12wt% sodium hydroxide aqueous solution, react for 1-2 hours, then add 6-9 parts by weight of 20-30wt% chloroacetic acid aqueous solution and react at 60-62°C. After the reaction, wash with ethanol, add 5-8 parts by weight of hydrochloric acid to neutrality and continue to react for 2-3 hours. After the reaction, wash with ethanol again to neutrality, and obtain carboxymethyl chitosan by freeze drying; S3.2: Dissolve 5-8 parts by weight of carboxymethyl chitosan in 20-30 parts by weight of deionized water, stir and mix to obtain a carboxymethyl chitosan solution, then dissolve 2-3 parts by weight of glucuronic acid in 10-12 parts by weight of deionized water, stir and mix, add 1-2 parts by weight of N, N'-dicyclohexylcarbodiimide, stir for 5-8h, and obtain a glucuronic acid solution; S3.3: Add the glucuronic acid solution dropwise to the carboxymethyl chitosan solution, and stir and mix continuously for 10-12 hours. After the reaction is completed, use tetrahydrofuran to separate the phases, remove the lower layer, wash and dry, and obtain glucuronic acid grafted carboxymethyl chitosan; S3.4: Dissolve the glucuronic acid grafted carboxymethyl chitosan in 10-12 parts by weight of dimethyl sulfoxide solution at 40-45°C, stir and mix, add 3-5 parts by weight of 40-50wt% polyvinyl alcohol aqueous solution, then add 0.05-0.08 parts by weight of ammonium persulfate, stir and mix, and then graft react at 50-60°C for 2-3h. After the reaction, dialyze and purify the product and dry it to obtain a polymer binder.

5. The preparation process of azomethasone water dispersible granules according to claim 4, characterized in that: Step S4: Preparation of nano-auxiliary agents, specifically comprising the following steps: S4.1: Add 0.4-0.8 parts by weight of triethanolamine to 120-150 parts by weight of deionized water, and perform ultrasonic dispersion for 20-30 minutes, and then stir and mix at 75-80° C. for 20-30 minutes, and then add 1.5-2 parts by weight of hexadecyltrimethylammonium bromide, and continue stirring for 1-2 hours, and finally add 10-12 parts by weight of tetraethyl orthosilicate and 9-10 parts by weight of bis[3-(triethoxysilyl)propyl]tetrasulfide, and stir and mix at 75-80° C. for 10-12 hours to obtain a reaction system; S4.2: The reaction system is centrifuged at 11000-12000 r / min to obtain a precipitate, which is washed with anhydrous ethanol for 2-3 times, and then washed with an acidic ethanol solution at 60-62° C. for 10-12 h. The product is collected by centrifugation again and washed with anhydrous ethanol for three times. After centrifugation, the solid is placed in a vacuum drying oven and dried for 10-12 h to obtain mesoporous organic silica nanoparticles; S4.3: Disperse 1-2 parts by weight of mesoporous organic silica nanoparticles in 250-300 parts by weight of Tris-HCl buffer with a pH of 8.5, ultrasonically disperse for 20-30 minutes, and then stir for 20-30 minutes. Then add 0.5-1 parts by weight of dopamine hydrochloride solid powder, stir and mix for 8-10 hours, then add 1-2 parts by weight of apricot wood vinegar, stir and mix for 10-12 hours, and centrifuge at 11000-12000r / min. Wash the precipitate with deionized water 2-3 times, and then wash with ethanol 1-2 times, and obtain the nano-additive after vacuum drying.

6. The process for preparing azomethasone water dispersible granules according to claim 5, characterized in that: Step S5: Preparation of water dispersible granules, specifically comprising the following steps: S5.1: 40-50 parts by weight of microcapsule flexible particles, 10-20 parts by weight of nano additives, 2-8 parts by weight of sodium lauryl sulfate, 5-8 parts by weight of lignin sulfonate, 20-30 parts by weight of calcium chloride, 1-2 parts by weight of isooctyl alcohol and 20-30 parts by weight of diatomaceous earth are mixed to obtain a mixture; S5.2: The mixture is ultrafinely ground by a jet mill to obtain a mother powder. The mother powder, 5-8 parts by weight of a polymer binder and 1-2 parts by weight of deionized water are placed in a kneader and kneaded, and then passed into an extrusion granulator for granulation to obtain water-dispersible granules.

7. The process for preparing azomethasone water dispersible granules according to claim 5, characterized in that: The volume ratio of hydrochloric acid to anhydrous ethanol in the acidic ethanol solution in step S4.2 is 4-5:95-96.

8. A water dispersible granule of thiazolin, characterized in that: The invention is prepared by the preparation process of azomethasone water dispersible granules according to any one of claims 1 to 7.

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