A highly dispersible diuron wettable powder and its preparation method

Abstract

This invention discloses a highly dispersible diuron wettable powder and its preparation method, relating to the field of pesticide technology. The powder comprises the following components: diuron technical grade, a composite dispersing and antiflocculating agent composed of sodium citrate and potassium pyrophosphate, silica, filler, a wetting agent composed of sodium dodecylbenzenesulfonate and fatty alcohol polyoxyethylene ether, and a stabilizer. The composite dispersing and antiflocculating agent, composed of sodium citrate and potassium pyrophosphate in a specific ratio, compared to a single antiflocculating agent, can form a stable double electric layer on the surface of diuron particles through the synergistic effect of charge complementarity and steric hindrance, effectively preventing particle agglomeration and flocculation, and improving the fluidity of the suspension. The composite wetting agent, composed of sodium dodecylbenzenesulfonate and fatty alcohol polyoxyethylene ether, combines the rapid wetting properties of anionic surfactants with the long-lasting dispersing properties of nonionic surfactants, enabling the powder to rapidly disintegrate and disperse in water.

Description

Technical Field

[0001] This invention relates to the field of pesticide technology, specifically to a highly dispersible diuron wettable powder and its preparation method. Background Technology

[0002] Diuron is a highly effective, broad-spectrum phenylurea herbicide that achieves its weed-control effect by inhibiting the Hill reaction in photosynthesis. It is widely applicable to weed control in various crops such as cotton, corn, sugarcane, and orchards, playing a vital role in agricultural production. Currently, commercially available diuron wettable powders generally suffer from technical bottlenecks such as low suspension rate (usually below 80%), poor physical stability, easy clumping during storage, and poor dispersibility. These issues not only lead to unstable efficacy and insufficient bioavailability during field application but also easily cause localized phytotoxicity or incomplete weed control due to uneven dispersion. Furthermore, conventional wettable powders are prone to agglomeration and rapid sedimentation when diluted with water for spraying, increasing the difficulty of application for operators and hindering the market competitiveness of diuron wettable powders.

[0003] To address these issues, existing technologies often improve upon existing methods by adding single antiflocculation agents or carriers. However, these methods suffer from problems such as unreasonable formulation combinations and poor synergistic effects among components, making it difficult to simultaneously achieve the combined effects of increased suspension rate, anti-caking, and high dispersibility. Furthermore, some technologies employ adjuvant systems with poor compatibility, which can easily interact with diuron technical grade pesticides, affecting pesticide stability and herbicidal efficacy. Additionally, some adjuvants are difficult to biodegrade, potentially causing damage to the soil microenvironment, which does not meet the requirements for the development of green agriculture.

[0004] Therefore, developing a wettable powder of diuron with high suspension rate, excellent dispersibility, good physical stability, and environmental friendliness has become an urgent need in the field of pesticide formulation. Summary of the Invention

[0005] The present invention aims to solve the technical problems of low suspension rate, poor dispersibility and easy agglomeration during storage of existing diuron wettable powder.

[0006] To address the above problems, the present invention provides a highly dispersible diuron wettable powder, comprising the following components in parts by weight: The mixture contains 30-50 parts of diuron technical grade, 8-15 parts of compound dispersing antiflocculation agent, 10-20 parts of precipitated silica, 20-40 parts of filler, 2-5 parts of wetting agent, and 1-3 parts of stabilizer; among which... The composite dispersing antiflocculation agent is a mixture of sodium citrate and potassium pyrophosphate in a mass ratio of 1:(0.8-1.2). The wetting agent is a compound of sodium dodecylbenzenesulfonate and fatty alcohol polyoxyethylene ether in a mass ratio of 1:(0.5-0.8).

[0007] The highly dispersible diuron wettable powder provided by this invention has, but is not limited to, the following beneficial effects compared to the prior art: This invention relates to a highly dispersible diuron wettable powder, which achieves synergistic effects by scientifically proportioning diuron technical material with a composite dispersant and antiflocculator, silica, filler, wetting agent, and stabilizer. Specifically, the composite dispersant and antiflocculator, a mixture of sodium citrate and potassium pyrophosphate in a specific ratio, forms a stable double electric layer on the surface of diuron particles through charge complementarity and steric hindrance, effectively preventing particle agglomeration and improving suspension flowability compared to a single antiflocculator. The composite wetting agent, a mixture of sodium dodecylbenzenesulfonate and fatty alcohol polyoxyethylene ether, combines the rapid wetting properties of anionic surfactants with the long-lasting dispersing properties of nonionic surfactants, enabling the powder to rapidly disintegrate and disperse in water. Extensive testing has verified the proportions of each component, ensuring high dispersibility, high suspension rate, and good physical stability while also considering raw material costs and the feasibility of industrial production. This solves the problems of low suspension rate, poor dispersibility, and easy clumping during storage associated with existing diuron wettable powders.

[0008] Preferably, the mass fraction of the diuron technical grade is ≥98%, and the particle size of the technical grade is D50=1~5um.

[0009] Specifically, a technical grade drug mass fraction ≥98% can effectively reduce the impact of impurities on the stability of the formulation system, avoid adverse interactions between impurities and adjuvants, and ensure herbicidal activity while improving the storage stability of the formulation. The technical grade drug particle size is controlled at D50=1~5um. At this particle size, the specific surface area of ​​the technical grade drug is moderate, which can fully contact and combine with various adjuvants to improve dispersibility and suspension, and will not cause the powder to be scattered and lost during production, packaging and application due to excessively small particle size, thus taking into account both formulation performance and ease of use.

[0010] Preferably, the silica is fumed silica, and the specific surface area of ​​the fumed silica is 200-300 m² / g. 2 / g, oil absorption value is 200~300mL / 100g.

[0011] Specifically, fumed silica is selected because it has a higher specific surface area and superior adsorption performance compared to precipitated silica. It can uniformly adsorb diuron technical grade particles and various adjuvants, forming a stable adsorption system and effectively preventing the sedimentation and aggregation of technical grade particles; the specific surface area is 200–300 m² / g. 2 Within the index range of 200-300 mL / 100 g and oil absorption value, the adsorption capacity and dispersion effect of fumed silica achieve the best balance. It can fully load the active ingredient and adjuvants, while ensuring that the formulation has good flowability, avoiding powder agglomeration due to excessive adsorption capacity, and improving the persistence of the formulation under complex field conditions such as rain and high temperature.

[0012] Preferably, the filler is a mixture of kaolin and diatomaceous earth in a mass ratio of 1:(1-2).

[0013] Specifically, kaolin and diatomaceous earth are selected as fillers in a 1:(1-2) ratio. Both are natural inert mineral materials that do not interact with diuron technical and various adjuvants, and will not affect the efficacy of the formulation. Kaolin has good formability and adsorption properties, which can improve the physical formability of the powder and prevent moisture absorption and clumping during storage. Diatomaceous earth has a porous structure, which can help disperse the technical particles and adsorb excess adjuvants to ensure the uniformity of the formulation system. Moreover, the pore structure of the two after compounding is complementary. Compared with a single filler, it can effectively dilute the concentration of the technical and adapt to different field application needs. It can also further improve the physical stability and dispersibility of the formulation. In addition, the raw material cost is low, which meets the requirements of large-scale industrial production.

[0014] Preferably, the fatty alcohol polyoxyethylene ether is fatty alcohol polyoxyethylene ether AEO-7, and the HLB value of fatty alcohol polyoxyethylene ether AEO-7 is 10 to 12.

[0015] Specifically, fatty alcohol polyoxyethylene ether AEO-7 is selected. It is a nonionic surfactant with excellent compatibility with anionic sodium dodecylbenzene sulfonate, with no compatibility conflicts. After compounding, it will not produce precipitation or stratification, ensuring the stability of the formulation system. Its HLB value is limited to 10-12. This HLB value range is highly matched with the water dispersion requirements of pesticide wettable powders, which can enable the wetting agent to spread rapidly in water, achieve rapid wetting and disintegration of the powder, improve the dispersion persistence of the formulation in water, avoid the aggregation and sedimentation of the liquid, further ensure the uniformity of field application, and improve the weeding effect.

[0016] Preferably, the stabilizer is sodium alginate.

[0017] Specifically, sodium alginate is selected as a stabilizer. It is a natural polysaccharide polymer material with good biodegradability, which meets the requirements of green agriculture development and poses no risk of environmental residue. Sodium alginate can form a slight three-dimensional gel network in water, which can adsorb and encapsulate diuron technical particles, slow down the Brownian motion and sedimentation rate of the particles, and further improve the suspension stability of the formulation. At the same time, sodium alginate can form a protective film on the surface of powder particles, effectively preventing the powder from absorbing moisture and clumping during storage, improving the storage stability of the formulation, and ensuring the performance stability of the product within its shelf life.

[0018] The present invention also provides a method for preparing the highly dispersible diuron wettable powder as described above, comprising the following steps: Step 1: Crush the diuron technical grade, precipitated silica, and filler separately and set aside; Step 2: Add the prepared silica and filler to the twin-screw mixer and mix at 200-300 rpm for 5-8 minutes at 20-35℃ to obtain the mixed carrier; Step 3: Add the prepared diuron technical, compound dispersant and antiflocculation agent, and wetting agent to the mixed carrier, and continue mixing at 250-350 rpm for 10-15 minutes at 20-35℃ to obtain the initial mixture; Step 4: Add stabilizer to the initial mixture and mix at 150-200 rpm for 3-5 minutes at 20-35°C to obtain the mixture; Step 5: Test the fineness and suspension rate of the mixture. After passing the test, vacuum package it to obtain highly dispersible diuron wettable powder.

[0019] The method for preparing highly dispersible diuron wettable powder provided by this invention has, but is not limited to, the following beneficial effects compared to the prior art: The preparation process employs a stepwise pulverization and gradient mixing technique. First, each solid raw material is pulverized to a specific particle size to ensure dispersibility and avoid poor dispersion due to uneven particle size during mixing. The mixing process consists of three steps: premixing the carrier, mixing the main active ingredient and functional additives, and using a low-speed mixing stabilizer. The premixing carrier ensures the uniformity of the silica and fillers, laying the foundation for subsequent active ingredient dispersion. High-speed main mixing ensures thorough integration of the active ingredient with the composite dispersing anti-flocculation agent and wetting agent. The low-speed mixing stabilizer prevents molecular chain breakage of high-molecular-weight sodium alginate due to high-speed shearing, ensuring its stabilizing effect. The entire preparation process is simple, requires minimal equipment, and the process parameters have been optimized through experimentation, making it easy to achieve large-scale industrial production while ensuring product quality uniformity.

[0020] Preferably, in step 1, the pulverization is carried out using an air jet mill, with a compressed air pressure of 0.7 to 0.9 MPa and a feed rate of 10 to 20 kg / h.

[0021] Specifically, air jet mills are used for pulverization. Compared with other pulverizing equipment, air jet mills have higher pulverization precision, enabling precise control of raw material particle size and avoiding large-diameter particles that could affect the dispersibility and suspension of the formulation. With compressed air pressure ranging from 0.7 to 0.9 MPa and a feed rate of 10 to 20 kg / h, the raw materials can be fully impacted and pulverized within the mill, ensuring that the pulverized material has a uniform particle size and meets the requirement of 350 to 400 mesh. At the same time, pulverization efficiency is also taken into account, avoiding raw material loss due to excessive pressure or insufficient pulverization due to excessively fast feed rate, thus improving the raw material utilization rate and production efficiency in the production process.

[0022] Preferably, in step 4, the pass standard for the fineness test is that the mass fraction of the residue on a 350-mesh standard sieve is ≤1.0%.

[0023] Specifically, the mass fraction of residue passing through a 325-mesh standard sieve is limited to ≤1.0% to ensure that there are no large-diameter particles in the formulation. Large-diameter particles are an important factor leading to poor dispersibility and low suspension rate of the formulation. This qualified standard can ensure the uniformity of the raw materials of the formulation, so that the formulation can quickly and uniformly disintegrate and disperse in water, avoiding the stratification of the liquid due to the sedimentation of large-diameter particles. At the same time, it ensures that the pesticide can be evenly attached to the surface of weeds during field application, improving the weeding effect. It also provides clear quality testing indicators for industrial production, which facilitates product quality control.

[0024] Preferably, in step 4, the pass standard for the suspension rate test is a suspension rate ≥ 90%.

[0025] Specifically, a suspension rate of ≥90% allows the diuron technical grade granules to remain suspended in water for an extended period, ensuring uniformity of the pesticide solution during field application. This avoids uneven application due to pesticide sedimentation, preventing localized phytotoxicity or incomplete weed control. At the same time, it improves the bioavailability of the technical grade, reduces pesticide waste, and lowers agricultural production costs. Detailed Implementation

[0026] The specific embodiments of the present invention will be described in detail below, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.

[0027] The terminology used in the embodiments of this application is for the purpose of describing particular implementations only and is not intended to be limiting of this application. The singular forms “a,” “the,” and “the” used in the implementations of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0028] It should be understood that in the various embodiments of this application, the sequence number of each process does not imply the order of execution. Some or all steps may be executed in parallel or sequentially. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the implementation regulations of this application.

[0029] The weights of the relevant components mentioned in the embodiments of this application can refer not only to the specific content of each component, but also to the proportional relationship between the weights of the components. Therefore, any scaling up or down of the content of the relevant components according to the embodiments of this application is within the scope disclosed in the embodiments of this application. Specifically, the mass described in the embodiments of this application can be a mass unit known in the chemical industry, such as μg, mg, g, or kg.

[0030] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of the invention.

[0031] Unless otherwise specified, all raw materials, reagents, instruments, and equipment used in this application can be purchased commercially or prepared using existing methods; for example, the specific types and sources of raw materials involved in the following examples and comparative examples are as follows: Diuron technical grade: Shandong Binnong Technology Co., Ltd., model: DL-01, conforms to GB 23555-2009 standard, mass fraction 98.5%; Sodium citrate: purchased from Weifang Yingxuan Industrial Co., Ltd., food grade, model: SC-99, mass fraction ≥99%; Potassium pyrophosphate: purchased from Jiangsu Zhengtong Hongtai Co., Ltd., industrial grade, model: TKPP-98, mass fraction ≥98%; Silica: Purchased from Cabot Chemicals (Tianjin) Co., Ltd., model: CAB-O-SIL M-5, specific surface area 200±25m² 2 / g, oil absorption value 250±30mL / 100g, conforming to HG / T 2567-2006 standard; Kaolin: Purchased from Maoming Kaolin Development Co., Ltd., calcined grade, model: GL-325, conforming to the standards for fillers used in pesticide adjuvants; Diatomite: Purchased from Changbaishan Diatomite Mining Co., Ltd., filter aid grade, model: DT-300, conforming to the standards for fillers used in pesticide adjuvants; Sodium dodecylbenzenesulfonate: purchased from Zanyu Technology Group Co., Ltd., industrial grade, model: LAS-96, mass fraction 96%; Fatty alcohol polyoxyethylene ether AEO-7: Purchased from Zhejiang Zanyu Technology Co., Ltd., industrial grade, model: AEO-7, HLB value 11, meets pesticide adjuvant standards; Sodium alginate: Purchased from Qingdao Mingyue Seaweed Group Co., Ltd., food grade, model: SA-150, viscosity 150mPa. s (1% aqueous solution), conforming to GB1886.230-2016 standard.

[0032] Example 1 This embodiment discloses a highly dispersible diuron wettable powder, which is prepared by following these steps: Before preparation, the raw materials are prepared in the following proportions by weight: 40 parts of diuron technical grade, 12 parts of a composite dispersing antiflocculation agent composed of sodium citrate and potassium pyrophosphate in a mass ratio of 1:1, 15 parts of precipitated silica, 30 parts of a filler composed of kaolin and diatomaceous earth in a mass ratio of 1:1.5, 3 parts of a wetting agent composed of sodium dodecylbenzene sulfonate and fatty alcohol polyoxyethylene ether AEO-7 in a mass ratio of 1:0.6, and 2 parts of sodium alginate. Step 1: Diuron technical grade, silica, and filler are separately fed into an air jet mill (model: QYF-100) for ultra-fine grinding. The grinding parameters are controlled as follows: compressed air pressure 0.8MPa, feed rate 15kg / h, and classifier wheel speed 4000rpm. After grinding, all materials pass through a 350-mesh standard sieve, and the residue is ≤0.5%. The particle size distribution of the ground material is tested: D90=42um, D50=12um. The ground material is then transferred to a drying storage chamber and cooled to 25℃ for later use. Step 2: Add the spare silica and filler to the twin-screw mixer (model: SHJ-500), mix at 250 rpm for 6 minutes at 30℃, stop the machine for 10 seconds after mixing is completed, check for any dead corners and material residue, and obtain the mixed carrier; Step 3: Add the prepared diuron technical, compound dispersant and antiflocculation agent, and wetting agent to the mixed carrier, and continue mixing at 300 rpm for 12 minutes at 30°C to obtain the initial mixture; Step 4: Add sodium alginate to the initial mixture and mix at 180 rpm for 4 minutes at 30°C to obtain the mixture, which is the highly dispersible diuron wettable powder.

[0033] Example 2 This embodiment discloses a highly dispersible diuron wettable powder, which is prepared by following these steps: Before preparation, the raw materials are prepared in the following proportions by weight: 30 parts of diuron technical grade, 8 parts of a composite dispersing antiflocculation agent composed of sodium citrate and potassium pyrophosphate in a mass ratio of 1:1, 10 parts of precipitated silica, 20 parts of a filler composed of kaolin and diatomaceous earth in a mass ratio of 1:1.5, 2 parts of a wetting agent composed of sodium dodecylbenzene sulfonate and fatty alcohol polyoxyethylene ether in a mass ratio of 1:0.6, and 1 part of sodium alginate. Steps 1 to 4 are exactly the same as in Example 1.

[0034] Example 3 This embodiment discloses a highly dispersible diuron wettable powder, which is prepared by following these steps: Before preparation, the raw materials are prepared in the following proportions by weight: 50 parts of diuron technical grade, 15 parts of a composite dispersing antiflocculation agent composed of sodium citrate and potassium pyrophosphate in a mass ratio of 1:1, 20 parts of precipitated silica, 40 parts of a filler composed of kaolin and diatomaceous earth in a mass ratio of 1:1.5, 5 parts of a wetting agent composed of sodium dodecylbenzenesulfonate and fatty alcohol polyoxyethylene ether in a mass ratio of 1:0.6, and 3 parts of sodium alginate. Steps 1 to 4 are exactly the same as in Example 1.

[0035] Example 4 This embodiment discloses a highly dispersible diuron wettable powder, which is prepared by following these steps: Before preparation, the raw materials are prepared in the following proportions by weight: 30 parts of diuron technical grade, 8 parts of a composite dispersing antiflocculation agent composed of sodium citrate and potassium pyrophosphate in a mass ratio of 1:0.8, 10 parts of precipitated silica, 20 parts of a filler composed of kaolin and diatomaceous earth in a mass ratio of 1:1, 2 parts of a wetting agent composed of sodium dodecylbenzene sulfonate and fatty alcohol polyoxyethylene ether in a mass ratio of 1:0.5, and 1 part of sodium alginate. Steps 1 to 4 are exactly the same as in Example 1.

[0036] Example 5 This embodiment discloses a highly dispersible diuron wettable powder, which is prepared by following these steps: Before preparation, the raw materials are prepared in the following proportions by weight: 30 parts of diuron technical grade, 8 parts of a composite dispersing antiflocculation agent composed of sodium citrate and potassium pyrophosphate in a mass ratio of 1:1.2, 10 parts of precipitated silica, 20 parts of a filler composed of kaolin and diatomaceous earth in a mass ratio of 1:0.8, 2 parts of a wetting agent composed of sodium dodecylbenzene sulfonate and fatty alcohol polyoxyethylene ether in a mass ratio of 1:2, and 1 part of sodium alginate. Steps 1 to 4 are exactly the same as in Example 1.

[0037] Comparative Example 1 Compared with Example 1, the only difference is that the composite dispersing antiflocculation agent is replaced with a single sodium citrate; all other conditions and steps are exactly the same as in Example 1, and a highly dispersible diuron wettable powder is finally obtained.

[0038] Comparative Example 2 Compared with Example 1, the only difference is that sodium alginate is omitted; all other conditions and steps are exactly the same as in Example 1, and a highly dispersible diuron wettable powder is finally obtained.

[0039] Performance tests were conducted on the highly dispersible diuron wettable powders of Examples 1-5 and Comparative Examples 1-2. The test items and methods are as follows: Fineness: Refer to GB / T mass fraction 16150-1995 "Determination of Fineness of Pesticide Powders and Wettable Powders", use the water washing method, weigh 50g of sample, pass through a 350 mass fraction standard sieve, collect the sieve residue, dry and weigh it, and calculate the mass fraction of the sieve residue. Suspension rate: Referring to GB / T 14825-2006 "Determination of Suspension Rate of Pesticide Wettable Powders", 250 mL of the suspension to be tested was prepared using standard hard water with a hardness of 342 mg / L (calculated as CaCO3). The suspension was placed in a constant temperature water bath at 25℃ for 30 min, and 225 mL of the clear liquid at the top was extracted. The liquid was filtered and the diuron content in the remaining 25 mL of liquid at the bottom was determined. The suspension rate was then calculated. Dispersion time: Refer to the CIPAC method for determining the dispersibility of wettable powders with mass fractions of CIPAC, MT, and 160. Add 100 mL of standard hard water to a 250 mL graduated cylinder. Drop 1 g of sample freely from a height of 1 cm above the water surface in the graduated cylinder and record the time it takes for the sample to completely disintegrate and disperse without any visible agglomerates. Storage status at room temperature for 6 months: In accordance with GB / T 19136-2003 "Determination of thermal storage stability of pesticides", the sample was sealed and stored in a constant temperature and humidity chamber at 25℃ and 60% relative humidity for 6 months. After storage, the appearance was observed and the dispersibility was retested.

[0040] The test results are listed in Table 1, as follows: Table 1

[0041] Analysis of the data in Table 1 shows that, compared to Comparative Examples 1-2, the highly dispersible diuron wettable powders of Examples 1-5 exhibit significantly better performance across all indicators. Specifically, the residue on the fine sieve is ≤0.5%, far below the acceptable standard of ≤1.0%, indicating that the raw materials are uniformly pulverized without large particles, laying the foundation for high dispersibility. The suspension rate is ≥91.8%, reaching a maximum of 95.2%, far exceeding the average level (≤80%) of existing commercially available diuron wettable powders, proving that the compound adjuvant system of this invention can effectively improve the suspension stability of the formulation. The dispersion time is within 60 seconds, achieving rapid disintegration and dispersion, eliminating the need for prolonged stirring during application and significantly improving the convenience of application. After 6 months of storage at room temperature, no clumping was observed in any of the examples, and the dispersibility did not decrease at all, demonstrating excellent physical stability and ensuring the product's stable performance within its shelf life.

[0042] Comparative Example 1 used sodium citrate as a single antiflocculation agent without using the compound system of this invention. Its suspension rate was only 83.1%, the dispersion time was extended to 88s, and slight agglomeration occurred after storage. This proves that the compound of sodium citrate and potassium pyrophosphate has a significant synergistic effect, and a single adjuvant cannot achieve the same dispersion and antiflocculation effect. Comparative Example 2 eliminated the sodium alginate stabilizer, and its suspension rate dropped to 87.6%. Some agglomeration occurred after storage, proving that sodium alginate plays a key role in improving the suspension stability and storage stability of the formulation.

[0043] The foregoing has provided a detailed description of one embodiment of the present invention, but this description is merely a preferred embodiment and should not be construed as limiting the scope of the invention. All equivalent variations and modifications made within the scope of the claims of this invention should still fall within the patent coverage of this invention.

Claims

1. A highly dispersible diuron wettable powder, characterized in that, The components include the following parts by weight: The mixture contains 30-50 parts of diuron technical grade, 8-15 parts of compound dispersing antiflocculation agent, 10-20 parts of precipitated silica, 20-40 parts of filler, 2-5 parts of wetting agent, and 1-3 parts of stabilizer; among which... The composite dispersing antiflocculation agent is a mixture of sodium citrate and potassium pyrophosphate in a mass ratio of 1:(0.8-1.2). The wetting agent is a compound of sodium dodecylbenzenesulfonate and fatty alcohol polyoxyethylene ether in a mass ratio of 1:(0.5-0.8).

2. The highly dispersible diuron wettable powder according to claim 1, characterized in that, The mass fraction of the diuron technical grade is ≥98%, and the particle size of the technical grade is D50=1~5um.

3. The highly dispersible diuron wettable powder according to claim 1, characterized in that, The silica is fumed silica, and the specific surface area of ​​the fumed silica is 200-300 m². 2 / g, oil absorption value is 200~300mL / 100g.

4. The highly dispersible diuron wettable powder according to claim 1, characterized in that, The filler is a mixture of kaolin and diatomaceous earth in a mass ratio of 1:(1-2).

5. The highly dispersible diuron wettable powder according to claim 1, characterized in that, The fatty alcohol polyoxyethylene ether is fatty alcohol polyoxyethylene ether AEO-7, and the HLB value of fatty alcohol polyoxyethylene ether AEO-7 is 10 to 12.

6. The highly dispersible diuron wettable powder according to claim 1, characterized in that, The stabilizer is sodium alginate.

7. A preparation method for preparing the highly dispersible diuron wettable powder as described in any one of claims 1 to 6, characterized in that, Includes the following steps: Step 1: Crush the diuron technical grade, precipitated silica, and filler separately and set aside; Step 2: Add the prepared silica and filler to the twin-screw mixer and mix at 200-300 rpm for 5-8 minutes at 20-35℃ to obtain the mixed carrier; Step 3: Add the prepared diuron technical, compound dispersant and antiflocculation agent, and wetting agent to the mixed carrier, and continue mixing at 250-350 rpm for 10-15 minutes at 20-35℃ to obtain the initial mixture; Step 4: Add stabilizer to the initial mixture and mix at 150-200 rpm for 3-5 minutes at 20-35°C to obtain the mixture; Step 5: Test the fineness and suspension rate of the mixture. After passing the test, vacuum package it to obtain highly dispersible diuron wettable powder.

8. The preparation method according to claim 7, characterized in that, In step 1, the pulverization is carried out using an air jet mill, with a compressed air pressure of 0.7 to 0.9 MPa and a feed rate of 10 to 20 kg / h.

9. The preparation method according to claim 7, characterized in that, In step 5, the pass standard for fineness testing is that the mass fraction of residue on a 350-mesh standard sieve is ≤1.0%.

10. The preparation method according to claim 7, characterized in that, In step 5, the pass standard for the suspension rate test is a suspension rate ≥ 90%.

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