AU2019341143A1

AU2019341143A1 - Water-dispersible granules containing pyraclostrobin and preparation method therefor

Info

Publication number: AU2019341143A1
Application number: AU2019341143A
Authority: AU
Inventors: Xiuli DING; Hui JING; Guangze Li
Original assignee: Shenzhen Noposion Agrochemicals Co Ltd
Current assignee: Shenzhen Noposion Agrochemicals Co Ltd
Priority date: 2018-09-18
Filing date: 2019-08-09
Publication date: 2021-01-21
Also published as: CN109221208A; WO2020057289A1

Abstract

Disclosed are water-dispersible granules containing pyraclostrobin and a preparation method therefor, the method comprising: preparing pyraclostrobin into a microcapsule preparation with an average particle diameter of 0.5 μm to 2.0 μm by means of interface polymerization after heating and melting, then mixing same evenly with an aqueous sanding slurry of an auxiliary with an average particle diameter of 0.5 μm to 2.0 μm or an aqueous sanding slurry containing tebuconazole or cymoxanil, and spray-drying same to prepare the water-dispersible granules containing pyraclostrobin. By means of the above-mentioned method, the technical problem that pyraclostrobin easily melts, adheres or livers during airflow milling or sanding is avoided, in turn improving the dispersibility, suspension rate and storage stability of the water-dispersible granules containing pyraclostrobin; meanwhile, the water-dispersible granules containing pyraclostrobin have a certain slow-release property and can continuously and effectively control a variety of plant diseases.

Description

WATER-DISPERSIBLE GRANULES CONTAINING PYRACLOSTROBIN AND PREPARATION METHOD THEREFOR TECHNICAL FIELD

The invention pertains to the field of pesticide preparations, and particularly

relates to water-dispersible granules containing pyraclostrobin and preparation method therefor.

BACKGROUND

pyraclostrobin, a methoxy acrylate bactericide, is a mitochondrial respiration inhibitor. It destroys energy transfer by preventing electron transfer during

cytochrome synthesis. It has protective, therapeutic, and leaf penetration and

conduction effects. pyraclostrobin is a broad-spectrum fungicide, especially suitable for crops with mixed diseases. It is registered for more than 100 crops to be used to

control at least 49 diseases, involving the major pathogenic bacteria in all four

subphyla in the fungal classification. Besides, pyraclostrobin has significant resistance and healthcare effects, and has broad application prospects.

pyraclostrobin has four different crystal forms, the melting points of which are

different but the biological activities are completely the same. The different crystal forms of the raw pesticide can be transformed into each other under certain conditions.

The melting point of the first crystal form is 55°Cto 56°C the melting point of the

second crystal form is 57°C to 58°C, the melting point of the third crystal form is 59°C to 60°C, and the melting point of the fourth crystal form is 65°C to 67°C. The

processed formulations of pyraclostrobin include emulsifiable oils, suspensions,

water-dispersible granules, etc. pyraclostrobin has a relatively high solubility in organic solvents. The four crystal forms of pyraclostrobin raw pesticides are suitable

for preparing emulsifiable oils formulations. However, water suspension and

water-dispersible granules have higher requirements for the melting point of the raw pesticide. The fourth crystal form of pyraclostrobin raw pesticide is more suitable for

preparing water suspension and water-dispersible granules. When the first crystal

form, the second crystal form and the third crystal form of the pyraclostrobin raw pesticide with a lower melting point are sand-milled or jet-pulverized, on the one hand, due to the increase of temperature, the shape of the raw pesticide particle changes from solid to liquid (melting); on the other hand, as the particle size decreases, the specific surface area increases, and the particles become smaller, the melting probability will increase, and the temperature will increase, resulting in material adhering or creaming, which seriously affects the dispersion of water-dispersible granules, suspensibility, storage stability, etc., which in turn affects the bioavailability and efficacy of pyraclostrobin.

There are two methods for preparing conventional water-dispersible granules.

One method is dry (air jet) pulverization-fluidized bed granulation or extrusion granulation, and the second method is wet (sand-milling) pulverization-spray

granulation. Chinese invention patent CN106172385A discloses a method for

preparing water-dispersible granules containing pyraclostrobin by wet sand-milling and spray-drying, and CN 10272637B discloses a method for processing

water-dispersible granules containing pyraclostrobin by dry airflow grinding and

rotational fluidized bed granulating. These two processing methods have strict requirements on the crystal form of the pyraclostrobin raw pesticide in practical

applications. The crystal forms with a lower melting point or the mixed crystal forms

of the raw pesticide will melt due to the increase of temperature during crushing and/or granulating, which will affect normal production or result in poor product

quality.

TECHNICAL PROBLEMS The embodiment of the present invention provides a water-dispersible granule

containing pyraclostrobin and a preparation method therefor, to solve the technical

problems that the existing materials containing pyraclostrobin are easy to melt, adhere or cream during airflow pulverization or sand grinding, as well as of poor

dispersibility, low suspensibility and unsatisfactory efficacy of the water-dispersible

granules containing pyraclostrobin due to material melting, adhesion or creaming. TECHNICAL SOLUTIONS

The embodiments of the present invention are realized in such way. In the first

aspect, a water-dispersible granule containing pyraclostrobin is provided. The pyraclostrobin in the water-dispersible granules is coated in microcapsules, and the water-dispersible granules containing pyraclostrobin have a single pesticide active ingredient, or are water-dispersible granules of pyraclostrobin compounded with tebuconazole and water-dispersible granules of pyraclostrobin compounded with cymoxanil.

In the second aspect, a method for preparing water-dispersible granules

containing pyraclostrobin is provided, which includes a method for preparing water-dispersible granules of pyraclostrobin with a single pesticide active ingredient,

water-dispersible granules of pyraclostrobin compounded with tebuconazole and

water-dispersible granules of pyraclostrobin compounded with cymoxanil, the preparation of the water-dispersible granules containing pyraclostrobin of the present

invention includes three steps: step 1 is to prepare a water suspension of

pyraclostrobin microcapsules, step 2 is to prepare an aqueous sand-milling slurry, and step 3 is to prepare water-dispersible granules containing pyraclostrobin.

BENEFICIAL EFFECTS

In the embodiment of the present invention, in the water-dispersible granules containing pyraclostrobin, the pyraclostrobin is used as the core material of the

microcapsules to be coated in a capsule shell with a certain degree of porosity. The

capsule shell on the one hand prevents the influence of the bad environment on the capsule core material and reduces the degradation rate of pyraclostrobin in the capsule

core. On the other hand, it can control the pyraclostrobin in the capsule core to pass

through the capsule shell and release to the surrounding environment at a certain speed, effectively prolonging the action period of pyraclostrobin, improving the

bioavailability, promoting its resistance and healthcare effects, and improving the

controlling effect of plant diseases. In the water-dispersible granules of pyraclostrobin compounded with tebuconazole and the water-dispersible granules of pyraclostrobin

compounded with cyazofamid according to the present invention, the pyraclostrobin

is coated in microcapsules, which effectively controls the adverse effects between the different components in the compounded water-dispersible granules, and promotes the

synergistic effect of pyraclostrobin and tebuconazole or cymoxanil. Besides, the

water-dispersible granules of pyraclostrobin of the present invention have a sustained-release property, which can reduce the frequency of pesticide administration and sustainably control a variety of plant diseases.

The method for preparing the water-dispersible granules containing

pyraclostrobin of the present invention is realized by preparing pyraclostrobin into a water suspension of nearly spherical microcapsule pesticides with an average particle

size of 0.5 m to 2.0 m. It solves the technical problem that the pyraclostrobin is

easy to melt, adhere or cream during airflow pulverization or sand grinding, and improves the dispersibility, suspensibility and storage stability of water-dispersible

granules containing pyraclostrobin. . DETAILED DESCRIPTION OF THE EMBODIMENTS In order to make the purposes, technical solutions and advantages of the present

invention clearer, the present invention will be further described in detail below in

conjunction with embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, but not to limit the

present invention.

In the embodiment of the present invention, there is provided a water-dispersible granule containing pyraclostrobin. The pyraclostrobin in the water-dispersible

granules is coated in microcapsules. The water-dispersible granules of pyraclostrobin

have a single pesticide active ingredient, or are the water-dispersible granules of pyraclostrobin compounded with tebuconazole, and the water-dispersible granules of

pyraclostrobin compounded with cymoxanil.

In another aspect of the present invention, there is provided a method for preparing water-dispersible granules containing pyraclostrobin, which includes a

method for preparing water-dispersible granules of pyraclostrobin with a single

pesticide active ingredient, water-dispersible granules of pyraclostrobin compounded with tebuconazole and water-dispersible granules of pyraclostrobin compounded with

cymoxanil, the preparation of the water-dispersible granules containing pyraclostrobin

of the present invention includes three steps: step 1 is to prepare a water suspension of pyraclostrobin microcapsules, step 2 is to prepare an aqueous sand-milling slurry, and

step 3 is to prepare water-dispersible granules containing pyraclostrobin. Specific

steps are as follows: Step 1: Preparation of water suspension of pyraclostrobin microcapsules

Pyraclostrobin is heated to melt, then mixed uniformly with polymethylene

polyphenyl isocyanate to prepare an oil phase; the emulsifying dispersant is dissolved

in water to prepare an aqueous phase; the water phase and the oil phase are shear-mixed to form an O/W emulsion with an average particle size of 0.5 m to 2.0

tm; an aqueous solution of an amine compound is added to the O/W emulsion to perform interfacial polymerization to obtain a water suspension of pyraclostrobin microcapsules.

Step 2: Preparation of aqueous sand-milling slurry

The wetting dispersant, pH regulators, defoamers, inert carriers and water are mixed uniformly, and sand-milled into an aqueous sand-milling slurry of the additives

as solid with an average particle size of 0.5 m to 2.0 m for use; or the wetting

dispersant, pH regulators, defoamers, inert carriers, water and tebuconazole or cymoxanil raw pesticides are mixed uniformly, and sand-milled into aqueous

sand-milling slurry of tebuconazole or aqueous sand-milling slurry of cymoxanil as

solid with an average particle size of 0.5am to 2.0 m for use. Step 3: Preparation of water-dispersible granules containing pyraclostrobin

Water suspension of pyraclostrobin microcapsules obtained in step 1 is mixed

uniformly with the aqueous sand-milling slurry of the additive obtained in step 2; or water suspension of pyraclostrobin microcapsules obtained in step 1 is mixed

uniformly with the aqueous sand-milling slurry of tebuconazole or the aqueous

sand-milling slurry of cymoxanil obtained in step 2, and the water is removed by spray-drying to obtain the water-dispersible granules containing pyraclostrobin of the

present invention, which includes water-dispersible granules of pyraclostrobin with a

single pesticide active ingredient, water-dispersible granules of pyraclostrobin compounded with tebuconazole or water-dispersible granules of pyraclostrobin

compounded with cymoxanil.

The mass ratio of pyraclostrobin in the water-dispersible granules of pyraclostrobin with a single pesticide active ingredient is 5% to 50%; and/or the mass

ratio of the total active ingredients in the water-dispersible granules of the

pyraclostrobin compounded with tebuconazole is 10% to 60%, and the mass ratio of pyraclostrobin to tebuconazole is 1:1 to 1:3; and/or the mass ratio of total active ingredients in the water-dispersible granules of cymostrobin compounded with cymoxanil is 10% to 60%, and the mass ratio of pyraclostrobin to cymoxanil is 1:1 to 1:6. The emulsifying dispersant described in step 1 is one or more of sodium lignosulfonate, polycarboxylate, castor oil polyoxyethylene ether and polyoxyethylene sorbitan monooleate; the amine compound is one or more of ethylenediamine, propylenediamine, hexamethylenediamine, diethylenetriamine and triethylenetetramine. The wetting dispersant described in step 2 is one or more of sodium lignosulfonate, polycarboxylate, alkyl sulfate, alkylsulfonate and alkylphenylsulfonate; the inert carrier is one or more of kaolin, white carbon black and diatomaceous earth; the pH regulator is citric acid; the defoamer is silicone defoamer. In the water-dispersible granules containing pyraclostrobin according to the present invention and a preparation method therefor, the crystal form of pyraclostrobin can be either of the first crystal form, the second crystal form, the third crystal form and the fourth crystal form, or a mixture of 2-4 crystal forms in any ratio, wherein tebuconazole or cymoxanil can be selectively replaced by hexaconazole, triadimenol, diniconazole, cyproconazole, epoxiconazole, cyanofamid, fludioxonil, tricyclazole, zineb, propineb, kresoxim-methyl, azoxystrobin and other fungicides, and can also be selectively replaced by chlorantraniliprole, flonicamid, thiamethoxam, imidacloprid, abamectin, spirodiclofen, etoxazole, tetramazine, etc; polymethylene polyphenyl isocyanate for preparing water suspension of pyraclostrobin microcapsule in step 1 can also be replaced by poly-diphenylmethane diisocyanate, poly-isophorone diisocyanate, poly-4,4'-dicyclohexylmethane diisocyanate, etc.; the emulsifing dispersant in step 1 can also be replaced by naphthalenesulfonate anionic surfactants, sulfate anionic surfactants, phosphate ester anionic surfactants, polyoxyethylene rosin acid esters, sorbitan esters, fatty acid polyoxyethylene esters, fatty alcohol polyoxyethylene ether, alkylphenol polyoxyethylene ether, etc. In order to illustrate the technical solution of the present invention, further description is performed below by specific embodiments. Embodiment 1:

Preparation of 5% water-dispersible granules of pyraclostrobin

Step 1 Preparation of 20% water suspension of pyraclostrobin microcapsules

41.Og pyraclostrobin raw pesticide (98%) was heated to 70°&5°Cunder stirring to melt, then 0.8g MR-200 (polymethylene polyphenyl isocyanate) was added and mixed

uniformly to prepare an oil phase, 12.0 g Ultrazine NA (lignosulfonate) and 2.Og

BY-125 (castor oil polyoxyethylene ether) were dissolved in 130g of water, stirred and dissolved to prepare a water phase, and the oil phase was added to the water

phase and shear-mixed to prepare O/W emulsion with the average particle size of

0.5tm to 2.0[tm, then 2.Og of 10% diethylenetriamine aqueous solution was slowly added to the emulsion under stirring, the reaction was kept at 70°&5°Cfor 1.0h, the pH

was adjusted to 5.0-7.0 with appropriate amount of citric acid after cooling to room

temperature, and the system was supplemented with water to 200.0g to prepare a 20% water suspension of pyraclostrobin microcapsule with a solid content of about 27%.

Step 2 Preparation of aqueous sand-milling slurry

200.0g of 20% SP-DF2222 (polycarboxylate), 250.0g Polyfon H,O (lignosulfonate) and 10.0g K12 (alkyl sulfate) were dissolved in water, the pH was

adjusted to 5.0-7.0 with appropriate amount of citric acid, then 300.Og calcined kaolin

was added and dispersed uniformly, the system was supplemented with water to 1000g, and then mixed uniformly and sand-milled to prepare aqueous sand-milling

slurry with an average particle size of 0.5[tm-2.0tm with a solid content of 60%.

Step 3 Preparation of 5% water-dispersible granules of pyraclostrobin 50.0 g of 20% pyraclostrobin microcapsule suspension obtained in step 1 and

310.8 g the aqueous sand-milling slurry obtained in step 2 were mixed uniformly, and

spray-dried to remove water, screened to remove particles smaller than 150 mesh, that is, 5% water-dispersible granules of pyraclostrobin.

Embodiment 2:

Preparation of 20% water-dispersible granules of pyraclostrobin Step 1 Preparation of 30% water suspension of pyraclostrobin microcapsules

61.3g pyraclostrobin raw pesticide (98%) was heated to 7 0 °&5°Cunder stirring to

melt, then 3.Og Mondur MRS (polymethylene polyphenyl isocyanate) was added and mixed uniformly to prepare an oil phase, 10.0g Borresperse NA (lignosulfonate) and

1.Og Tween-80 (polyoxyethylene sorbitan monooleate) were added and dissolved in

11g of water, stirred and dissolved to prepare a water phase, and the oil phase was

added to the water phase and shear-mixed to form an O/W emulsion with an average particle size of 0.5[tm-2.0jm, then 7.7g of 20% triethylenetetramine aqueous solution

was slowly added to the emulsion under stirring, the temperature was kept at 70°50 C

for 1.0h, and pH was adjusted to 5.0-7.0 with appropriate amount of citric acid after cooling to room temperature, and the system was supplemented with water to 200g to

prepare a 30% water suspension of pyraclostrobin microcapsule, with a solid content

of about 38.5%. Step 2 Preparation of aqueous sand-milling slurry

40.0g Morwet IP (alkylnaphthalene sulfonate) and 60.0g Agrilan 700

(polycarboxylate) were dissolved in water, the pH was adjusted to 5.0-7.0 with appropriate amount of citric acid, and then 450.0g diatomaceous earth was added to

disperse uniformly, and the system was supplemented with water to 1000g, mixed

well and sand-milled to prepare an aqueous sand-milling slurry with an average particle size of 0.5tm to 2.0tm with a solid content of 55%.

Step 3 Preparation of 20% water-dispersible granules of pyraclostrobin

133.3 g of the 30% pyraclostrobin microcapsule suspension obtained in step 1 and 270.3 g the aqueous sand-milling slurry obtained in step 2 were mixed uniformly,

spray-dried to remove the water, screened to remove particles smaller than 150 mesh,

that is, 20% water-dispersible granules of pyraclostrobin. Embodiment 3:

Preparation of 50% water-dispersible granules of pyraclostrobin

Step 1 Preparation of 50% water suspension of pyraclostrobin microcapsule 102.g pyraclostrobin raw pesticide (98%) was heated to 70°5°Cunder stirring

to melt, then 1.5g PM-200 (polymethylene polyphenyl isocyanate) was added and

mixed uniformly to prepare an oil phase. 5.Og 2700 (polycarboxylate) and 5.Og EL-80 (castor oil polyoxyethylene ether) were dissolved in 100g of water and stirred and

dissolved to prepare a water phase. The oil phase was added to the water phase and

shear-mixed to prepare O/W emulsion with an average particle size of 0.5[m-2.0m, then 1.3g of 50% hexamethylenediamine aqueous solution was slowly added to the emulsion under stirring, kept at 70°&5°Cand reacted for 1.0h, the pH was adjusted to

5.0-7.0 with appropriate amount of citric acid after cooling to room temperature, the

system was supplemented with water to 200.Og to prepare a 50% water suspension of pyraclostrobin microcapsule with a solid content of about 57.4%.

Step 2 Preparation of aqueous sand-milling slurry

60.Og of Reax AG (lignosulfonate) and 20.Og Tersperse 2700 (polycarboxylate) were dissolved in water, the pH was adjusted to 5-7 with appropriate amount of citric

acid, and then 300.0g of diatomaceous earth was added to disperse uniformly, and the

system was supplemented with water to 1000g, mixed well and sand-milled to prepare aqueous sand-milling slurry with an average particle size of 0.5tm to 2.0m with

solid content of 38%.

Step 3 Preparation of 50% water-dispersible granules of pyraclostrobin 200.0 g of 50% pyraclostrobin microcapsule suspension obtained in step 1 and

224.2 g the aqueous sand-milling slurry obtained in step 2 were mixed uniformly, and

spray-dried to remove the water, screened to remove particles smaller than 150 mesh, that is, 50% water-dispersible granules of pyraclostrobin.

Embodiment 4:

Preparation of 10% water-dispersible granules of pyraclostrobin and tebuconazole

Step 1 Preparation of 10% water suspension of pyraclostrobin microcapsule

20.4g pyraclostrobin raw pesticide (98%) was heated to 7 0 °&5°Cunder stirring to melt, then 3.Og Mondur MRS (polymethylene polyphenyl isocyanate) was added and

mixed uniformly to prepare an oil phase, and 30.g SMA 520 (polycarboxylate) was

dissolved in 1OOg of water and stirred and dissolved to prepare a water phase. The oil phase was added to the water phase and shear-mixed to prepare an O/W emulsion

with an average particle size of 0.5[tm-2.0[tm. 2.7g of 30% propylenediamine aqueous

solution was slowly added to the emulsion, the temperature was kept at 70°&5°Cfor 1.0h, the pH was adjusted to 5.0 to 7.0 with appropriate amount of citric acid after

cooling to room temperature, and the system was supplemented with water to 200.Og

to prepare 10% water suspension of pyraclostrobin microcapsule with a solid content of 27.1%.

Step 2 Preparation of 3% aqueous sand-milling slurry of tebuconazole

20.Og Reax 88B (lignosulfonate) and 50.Og Agrilan 700 (polycarboxylate) was

dissolved in water, the pH was adjusted to 5.0-7.0 with appropriate amount of citric acid, and then 31.3g tebuconazole (96%) and 416.7.0g diatomaceous earth were

added to disperse uniformly, the system was supplemented with water to 1000g,

mixed well and sand-milled to prepare an aqueous sand-milling slurry with an average particle size of 0.5 m to 2.0tm with a solid content of 51.8%.

Step 3 Preparation of water-dispersible granules of 5% pyraclostrobin + 5%

tebuconazole 100.0 g of 10% pyraclostrobin microcapsule suspension obtained in step 1 and

333.3 g the aqueous sand-milling slurry obtained in step 2 were mixed uniformly,

spray-dried to remove the water, and screened to remove particles smaller than 150 mesh to obtain 10% water-dispersible granules of pyraclostrobin and tebuconazole.

Embodiment 5:

Preparation of 40% water-dispersible granules of pyraclostrobin and tebuconazole

Step 1 Preparation of 25% water suspension of pyraclostrobin microcapsules

51.Og pyraclostrobin raw pesticide (98%) was heated to 7 0 °&5°Cunder stirring to melt, then 5.1g MR-200 (polymethylene polyphenyl isocyanate) was added and mixed

uniformly to prepare an oil phase. 0.5g Tween 80 (polyoxyethylene sorbitan

monooleate), 10.0g SP-3936 (25% polycarboxylate aqueous solution), 4.Og Reax 825E (lignosulfonate) were dissolved in 100g water, stirred and dissolved to form the

water phase. The oil phase was added to the water phase and shear-mixed to prepare

an O/W emulsion with an average particle size of 0.5tm to 2.0[am, and then 19.Og of % diethylenetriamine aqueous solution was slowly added to the emulsion under

stirring, the temperature was kept at 70°&5°Cfor 1.0h, the pH was adjusted to 5.0 to

7.0 with appropriate amount of citric acid after cooling to room temperature, and the system was supplemented with water to 200.Og to prepare a 25% water suspension of

pyraclostrobin microcapsule with a solid content of 32.5%.

Step 2 Preparation of 18% aqueous sand-milling slurry of tebuconazole 50.Og Agrilan 700 (polycarboxylate) and 100.Og Reax AG (lignosulfonate) were dissolved in water, the pH was adjusted to 5.0 to 7.0 with appropriate amount of citric acid, and 187.5g tebuconazole (96.0%) and 184.5g kaolin were uniformly dispersed, the system was supplemented with water to 1000g, mixed well and sand-milled to prepare aqueous sand-milling slurry with an average particle size of 0.5[m-2.0m with a solid content of 52.2%.

Step 3 Preparation of water-dispersible granules of 10% pyraclostrobin + 30% tebuconazole

80.0 g of the 25% pyraclostrobin microcapsule suspension obtained in step 1 and

333.3 g the aqueous sand-milling slurry obtained in step 2 were mixed uniformly, spray-dried to remove the water, screened to remove particles smaller than 150 mesh,

that is, water-dispersible granules of 40% pyraclostrobin and tebuconazole.

Embodiment 6: Preparation of water-dispersible granules of 60% pyraclostrobin and

tebuconazole

Step 1 Preparation of 40% water suspension of pyraclostrobin microcapsule 81.6g of pyraclostrobin raw pesticide (98%) was heated to 70°&5°Cunder stirring

to melt, then 3.3g PM-200 (polymethylene polyphenyl isocyanate) was added and

mixed uniformly to prepare an oil phase. 3.2g Reax lOOM (lignosulfonate) was dissolved in 1OOg of water and stirred and dissolved to prepare an aqueous phase. The

oil phase was added to the aqueous phase and shear-mixed to prepare an O/W

emulsion with an average particle size of 0.5tm to 2.0jm, and then 7.g of 10% ethylenediamine aqueous solution was slowly added to the emulsion under stirring, the temperature was kept at 70°&5°€or 1.h. The pH was adjusted to 5.0 to 7.0 with

appropriate amount of citric acid after cooling to room temperature, and the system was supplemented with water to 200.0g to prepare 15% water suspension of

pyraclostrobin microcapsules with a solid content of 44.4%.

Step 2 Preparation of 28% aqueous sand-milling slurry of tebuconazole 50.Og Tersperse 2700 (polycarboxylate) and 100.Og Reax 910 (lignosulfonate)

was dissolved in water, the pH was adjusted to 5.0 to 7.0 with appropriate amount of

citric acid, and then 291.7g tebuconazole (96%) and 103.Og of white carbon black were added and uniformly dispersed, the system was supplemented with water to

1000g, mixed well and sand-milled to prepare aqueous sand-milling slurry with an

average particle size of 0.5um to 2.0um with solid content of 54.5%.

Step 3 Preparation of water-dispersible granules of 20% pyraclostrobin + 40% tebuconazole

100.0 g of the 40% pyraclostrobin microcapsule suspension obtained in step 1

and 285.7 g of the 28% aqueous sand-milling slurry of tebuconazole obtained in step 2 were mixed uniformly, spray-dried to remove water, and screened to remove

particles smaller than 150 mesh, that is, water-dispersible granules of 60%

pyraclostrobin and tebuconazole. Embodiment 7:

Preparation of water-dispersible granules of 10% pyraclostrobin and cymoxanil

Step 1 Preparation of 10% water suspension of pyraclostrobin microcapsule The preparation of the 10% water suspension of pyraclostrobin microcapsule was

the same as step 1 in Embodiment 4. The obtained 10% water suspension of

pyraclostrobin microcapsule had a solid content of 27.1%. Step 2 Preparation of 3.5% aqueous sand-milling slurry of cymoxanil

50.Og Tersperse 2700 (polycarboxylate) and 100.Og Reax AG (lignosulfonate)

were dissolved in water, the pH was adjusted to 5.0 to 7.0 with appropriate amount of citric acid, and then 72.2g cymoxanil (97%) and 382.8g of kaolin were added and

uniformly dispersed, the system was supplemented with water to 1000g, mixed well

and sand-milled to prepare an aqueous sand-milling slurry with an average particle size of 0.5um-2.0um with solid content of 60.5%.

Step 3 Preparation of water-dispersible granules of 5% pyraclostrobin + 5%

cymoxanil 100.0 g of the 10% pyraclostrobin microcapsule suspension obtained in step 1

and 285.7 g of the 3.5% aqueous sand-milling slurry of cymoxanil obtained in step 2

were mixed uniformly, spray-dried to remove water, and screened to remove particles smaller than 150 mesh, that is, water-dispersible granules of 10% pyraclostrobin and

cymoxanil.

Embodiment 8: Preparation of water-dispersible granules of 60% pyraclostrobin and cymoxanil

Step 1 Preparation of 40% water suspension of pyraclostrobin microcapsule

The preparation of the 40% water suspension of pyraclostrobin microcapsule was

the same as that of step 1 in Embodiment 6. The obtained 40% water suspension of pyraclostrobin microcapsule had a solid content of 44.4%.

Step 2 Preparation of 25% aqueous sand-milling slurry of cymoxanil

120.0g Borresperse NA (lignosulfonate), 20.Og Agrilan 700 (polycarboxylate) were added, the pH was adjusted to 5.0 to 7.0 with appropriate amount of citric acid,

and then 255.lg cymoxanil (97%) and 91.0 g diatomaceous earth were added and

uniformly dispersed, and the system was supplemented with water to 1000g, mixed uniformly and sand-milled to prepare an aqueous sand-milling slurry with an average

particle size of 0.5 [m-2.0 m with a solid content of 48.6%.

Step 3 Preparation of water-dispersible granules of 20% pyraclostrobin + 40% cymoxanil

100.0 g of the 40% pyraclostrobin microcapsule suspension obtained in step 1

and 320.0 g of the 25% aqueous sand-milling slurry of cymoxanil obtained in step 2 were mixed uniformly, the water was removed by spray-drying, and screened to

remove particles smaller than 150 mesh, that is, water-dispersible granules of 60%

pyraclostrobin and cymoxanil. Embodiment 9:

Preparation of water-dispersible granules of 42% pyraclostrobin and cymoxanil

Step 1 Preparation of 25% water suspension of pyraclostrobin microcapsules The preparation of the 25% water suspension of pyraclostrobin microcapsule was

the same as step 1 in Embodiment 5. The obtained 25% water suspension of

pyraclostrobin microcapsule had a solid content of 32.5%. Step 2 Preparation of 20% aqueous sand-milling slurry of cymoxanil

300.Og of 20% SP-DF2222 (polycarboxylate) and 150.Og Polyfon T,F

(lignosulfonate) were dissolved in water, the pH was adjusted to 5.0 to 7.0 with appropriate amount of citric acid, and 206.2g cymoxanil raw pesticide (97%) and

95.g of kaolin were added and uniformly dispersed, the system was supplemented

with water to 1000g, mixed well and sand-milled to prepare an aqueous sand-milling slurry with an average particle size of 0.5 [m-2.0jm with solid content of 5.1%.

Step 3 Preparation of water-dispersible granules of 6% pyraclostrobin + 36%

cymoxanil 48.0 g of the 25% pyraclostrobin microcapsule suspension obtained in step 1 and 360.0 g of the 20% aqueous sand-milling slurry of cymoxanil obtained in step 2 were

mixed uniformly, and spray-dried to remove water, and screened to remove particles

smaller than 150 mesh, that is, water-dispersible granules of 42% pyraclostrobin and cymoxanil.

Compared with the method for preparing conventional water-dispersible granules,

the water-dispersible granules containing pyraclostrobin of the present invention can significantly improve the dispersibility of the formulation and the suspensibility and

storage stability of pesticide active ingredients. In order to illustrate the difference

between the water-dispersible granules of the present invention and a preparation method therefor, table 1 shows the test results of water-dispersible granules prepared

in the embodiments of the present invention and the pesticide active ingredients which

are commercial available or prepared by the conventional wet pulverization-spray granulation method and the main quality control items of the same content of

water-dispersible granules.

Table 1

thermal storage decomposition rate prepration ssesblt %

formulation dispersib (%) method or mple saility (%) tebuconazole or tebuconazole or sample source pyraclostrobin pyraclostrobin cymoxanil cymoxanil

Embodiment 99.5 99.9 / 0.0 %pyraclostrobin 1 WDG conventional( 92.7 90.2 / 3.5/ CK1) Embodiment 98.9 99.0 / 0.1 20%pyraclostrobi 2 n WDG commercial(C 90.3 85.4 / 4.5/ K2) Embodiment 99.7 99.5 / 0.0 50%pyraclostrobi 3 n WDG commercial(C 83.5 80.7 / 3.8/ K3)

Embodiment 10%pyraclostrobi 98.4 99.0 97.8 0.1 1.0 4 n -tebuconazole conventional( WD 90.1 90.5 92.3 2.5 1.5 CK4) Embodiment 40%pyraclostrobi 99.0 99.7 98.7 0.0 1.5 5 n -tebuconazole commercial(C WDG 90.1 85.0 97.4 3.7 3.9 K5) Embodiment 60%pyraclostrobi 98.7 98.9 97.7 0.1 2.3 6 n -tebuconazole commercial(C WDG 83.5 85.6 95.6 4.4 3.7 K6) Embodiment 10%pyraclostrobi 98.3 99.7 98.9 0.1 3.5 7 n -cymoxanil conventional( WDG 92.1 91.5 92.3 4.1 4.9 CK7) Embodiment 60%pyraclostrobi 97.4 99.5 95.4 0.0 3.0 8 n -cymoxanil commercial(C WDG 89.2 82.5 87.3 3.5 4.8 K8)

(continued)

thermal storage decomposition rate prepration suspensibility(00) formulation dispersib (%) method or mple saility (%) tebuconazole or tebuconazole or sample source pyraclostrobin cmanl pyraclostrobin cmoai cymoxanil cymoxanil

Embodiment 42%pyraclostrobi 98.0 99.7 95.5 0.0 2.5 9 n-cymoxanil commercial(C WDG 90.1 88.6 90.3 1.9 4.8 K9)

In the test method of dispersibility in table 1, a certain amount of

water-dispersible granules is added to a specified volume of water, stirred and mixed to form a suspension, then stood for a period of time to remove the top 9/10

suspension, and the bottom 1/10 suspension and precipitate are dried and tested by

gravimetric method; the suspensibility and thermal storage decomposition rate are determined in accordance with GB/T 14825-2006 or GB/T 19136-2003 respectively.

The following field efficacy test shows that, compared with the prior art, the

water-dispersible granules containing pyraclostrobin of the present invention can significantly improve the bioavailability, promote the effects of resistance and healthcare, and prolong the action period of pyraclostrobin, improve the controlling effect of plant diseases. The medicament used in the test is provided by the embodiments of the present invention. The control medicament is a similar commercial medicament. The used crops and their cultivation methods, the dosage, method and controlled object of the medicament are consistent with the similar commercial medicament, see Table 2.

Table 2 formulations control amount of of the controlled administr No. Name of medicament medicamen used crops active present object .ation t ingredient invention Embodiment CK2(comm strawberry/ powdery 150g/hm 2 spray 1 200%pyraclostrobin WDG 10/m pa 2 ercial) greenhouse mildew Embodiment CK3(comm strawberry/ powdery 150g/hm 2 spray 2 500%pyraclostrobin WDG 10/m pa 3 ercial) greenhouse mildew 40%pyraclostrobin-tebuco brown 160mg/K Embodiment CK5(comm apple/field brown 10mg/K 3 apefedspray nazole WDG (10%+30%) 5 ercial) blotch g

600%pyraclostrobin-tebuco Embodiment CK6(comm brown 150mg/K 4 apple/field spray nazole WDG (20%+40%) 6 ercial) blotch g

6 %pyraclostrobin -cymox Embodiment CK8(comm cucumber/g downy 180/hm 2 sra anil WDG (20%+40%) 8 ercial) reenhouse mildew

420pyaclstobicyox Embodiment CK9(comm cucumber/g downy 20/m anil WDG (6%o+36%o) 9 ercial) reenhouse mildew pa

In reference to the relevant methods of the "Guidelines for field efficacy trials of

pesticides" of the People's Republic of China, greenhouse strawberries, greenhouse

cucumbers and field apple orchards with the same crop varieties and the same crop condition, fertilizer and water management and disease occurrence are selected and

different treatment areas are divided. According to the test plan in table 2, the administration is calculated at the initial stage of the onset of the disease, and the occurrence of diseases in each treatment area was investigated and calculated at 7

days, 15 days and 30 days after the drug. The controlling effect of the formulations obtained in the embodiments of the present invention was significantly better than that of the similar commercial products. The controlling effect of each treatment area is shown in Table 3.

Table 3

Treated medicament and its source controlling effect (%) crops dosage 30 Name of medicament source 7 days 15 days days Embodiment 150g/hm2 79.6 84.2 79.5 2 200%pyraclostrobinWDG strawberry CK2(commer 150g/hm2 74.3 80.6 47.1 cial) (greenhouse) Embodiment 180g/hm2 81.9 85.3 80.2 3 500%pyraclostrobinWDG CK3(commer 180g/hm 2 76.5 79.4 48.2 cial) Embodiment 40%pyraclostrobin -tebuconaz 5 160mg/kg 78.9 88.8 78.2

oleWDG (10%+30%) CK5(commer e 160mg/kg 72.1 78.5 43.3 ape(il) 600opyraclostrobin tebuconaz Embodiment 5m/g 8. 867 03 ole WDG 615m/g 8. 867 03 (200%+40%o) CK6(commer 150mg/kg 74.2 77.8 45.6 cial) 60%pyraclostrobin -cymoxani Embodiment 1WDG 8 cucumber (20%+40%) CK8(commer 180g/hm 2 67.5 76.6 48.3 cial) (greenhouse) 420%pyraclostrobin -cymoxani Embodiment CK8(commer 220g/hm 2 79.2 86.5 69.8 1WDG 9 cial)

(6%o+36%o) c.l 220g/hm 2 71.7 78.6 50.4

The above-mentioned embodiments are only used to illustrate the technical solutions of the present invention, but not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions described in each embodiment, or they can make equivalent replacements for some of the technical features; these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included within the protection scope of the present invention.

Claims

What is claimed is: 1. A water-dispersible granule containing pyraclostrobin, wherein the

pyraclostrobin in the water-dispersible granules is coated in microcapsules; the water-dispersible granules are water-dispersible granules of pyraclostrobin

with a single pesticide active ingredient, or water-dispersible granules of pyraclostrobin compounded with tebuconazole, or water-dispersible granules of pyraclostrobin compounded with cymoxanil;

the mass ratio of pyraclostrobin in the water-dispersible granules of

pyraclostrobin with a single pesticide active ingredient is 5% to 50%; the total active ingredient content in the water-dispersible granules of

pyraclostrobin compounded with tebuconazole is 10% to 60%, and the mass ratio of

pyraclostrobin to tebuconazole of the active ingredient is 1:1 to 1:3; the total active ingredient content in the water-dispersible granules of

pyraclostrobin compounded with cymoxanil is 10% to 60%, and the mass ratio of

pyraclostrobin to cymoxanil of the active ingredients is 1:1 to 1:6. 2. The method for preparing water-dispersible granules containing pyraclostrobin

according to claim 1, including the following steps:

Step 1: Preparation of water suspension of pyraclostrobin microcapsules Pyraclostrobin is heated to melt, and mixed uniformly with polymethylene

polyphenyl isocyanate to prepare an oil phase; an emulsifying dispersant is dissolved

in water to prepare an aqueous phase; the water phase and the oil phase are mixed and shear-mixed to form an O/W emulsion with an average particle diameter of 0.5 m to
2.0 m; an aqueous solution of an amine compound is added to the O/W emulsion to

perform interfacial polymerization to obtain a water suspension of pyraclostrobin microcapsules;

Step 2: Preparation of aqueous sand-milling slurry

a wetting dispersant, pH regulators, defoamers, inert carriers and water are mixed uniformly, and sand-milled into an aqueous sand-milling slurry of the additives as

solid with an average particle size of 0.5 m to 2.0 m for use; or the wetting

dispersant, pH regulators, defoamers, inert carriers, water and tebuconazole or cymoxanil raw pesticides are mixed uniformly, and sand-milled into aqueous sand-milling slurry of tebuconazole or aqueous sand-milling slurry of cymoxanil as solid with an average particle size of 0.5 m to 2.0 m for use;

Step 3: Preparation of water-dispersible granules containing pyraclostrobin water suspension of pyraclostrobin microcapsules obtained in step 1 and the

aqueous sand-milling slurry of the additive obtained in step 2 are mixed uniformly; or

water suspension of pyraclostrobin microcapsules obtained in step 1 and the aqueous sand-milling slurry of tebuconazole or the aqueous sand-milling slurry of cymoxanil

obtained in step 2 are mixed uniformly, and the water is removed by spray-drying to

obtain the water-dispersible granules containing pyraclostrobin of the present invention, which includes water-dispersible granules of pyraclostrobin with a single

pesticide active ingredient, water-dispersible granules of pyraclostrobin compounded

with tebuconazole or water-dispersible granules of pyraclostrobin compounded with cymoxanil.
3. The method for preparing water-dispersible granules containing pyraclostrobin

according to claim 2, wherein the emulsifying dispersant in step 1 is one or more of sodium lignosulfonate, polycarboxylate, castor oil polyoxyethylene ether and

polyoxyethylene sorbitan monooleate;

the amine compound is one or more of ethylenediamine, propylenediamine, hexamethylenediamine, diethylenetriamine and triethylenetetramine.
4. The method for preparing water-dispersible granules containing pyraclostrobin

according to claim 2, wherein the wetting dispersant in step 2 is one or more of sodium lignosulfonate, polycarboxylate, alkyl sulfate and alkyl phenyl sulfonate;

the inert carrier is one or more of kaolin, white carbon black and diatomaceous

earth; the pH regulator is citric acid;

the defoamer is silicone defoamer.