A pesticide water-dispersible granule with excellent dispersibility and its preparation method

Abstract

The present invention discloses a water-dispersible pesticide granule with excellent dispersibility and a preparation method thereof. The water-dispersible pesticide granule with excellent dispersibility comprises abicyclon, oxadiazon, quinclorac, a modified dispersant, a wetting agent, a disintegrant, a binder, and a filler; the modified dispersant has the structure shown in Formula A below. The water-dispersible pesticide granule provided by the present invention utilizes a combination of abicyclon, oxadiazon, and quinclorac as the active pesticide ingredients and a modified dispersant. The granule exhibits excellent stability and significantly enhances dispersibility and suspension rate, thereby improving the pesticide's efficacy. #imgabs0#

Description

Technical Field

[0001] The present invention relates to the technical field of pesticide preparations, and in particular to a pesticide water-dispersible granule with excellent dispersibility and a preparation method thereof.

[0002] Using pesticides to control pests, diseases, and weeds is essential for ensuring high-quality and high-yield agricultural products. However, using a single herbicide has a limited control spectrum, is prone to developing resistance, and cannot effectively address unwanted plant damage in production. Herbicide blends offer advantages such as expanding the control spectrum, enhancing efficacy, and delaying the development of weed resistance, making them a popular application in production practices. Synergistic herbicides are particularly popular because their active components interact with each other, resulting in a combined effect that surpasses the theoretical sum of their individual effects. This can achieve twice the result with half the effort in practical applications and is therefore highly sought after by users.

[0003] Modern pesticide formulations are evolving toward water-based, ultrafine, dust-free, and controlled-release formulations. The transition from wettable powders to water-dispersible granules (WDGs) is a key trend in pesticide development. WDGs reduce the use of organic solvents, eliminate the dust pollution associated with wettable powders and dusts, and lower production and transportation costs. They are safer and more environmentally friendly, making them a crucial formulation in pesticide formulation. They reduce environmental pollution during processing and use, facilitate metering, packaging, and transportation, and lower costs for farmers, making them a major trend in pesticide development.

[0004] At present, water-dispersible granules are mainly composed of raw materials, dispersants, wetting agents, disintegrants, binders, fillers and other components. The selection of adjuvants is a key factor affecting the wettability, disintegration and suspension of water-dispersible granules, which in turn affects the retention amount and retention time of the drug solution on the plant surface and its ability to penetrate the plant epidermis, affecting the biological activity of the pesticide.

[0005] To achieve high pesticide efficiency, the pesticide solution must first be fully spread and retained on the target substance. This requires the solution to have low surface tension and good wettability and permeability on the target surface. Otherwise, the solution will be lost, which will inevitably affect the efficacy and directly cause serious environmental pollution. Due to the demands for efficiency, safety, and environmental protection, the active ingredients in existing water-dispersible pesticide granules are gradually being used in combination with multiple components. As the components become increasingly complex, the requirements for the adjuvant properties of the water-dispersible granules, especially the dispersibility, are also gradually increasing.

[0006] Therefore, there is an urgent need for a pesticide water-dispersible granule with strong stability and significantly enhanced dispersibility and suspension rate, thereby improving the efficacy of the pesticide. Summary of the Invention

[0007] Purpose of the invention: In view of the defects of the prior art, the purpose of the present invention is to provide a pesticide water-dispersible granule with excellent stability and can significantly enhance the dispersibility and suspension rate, thereby improving the efficacy of the pesticide and a preparation method thereof.

[0008] Technical Solution

[0009] A pesticide water-dispersible granule with excellent dispersibility, comprising oxadiazon, oxadiazon, quinclorac, a modified dispersant, a wetting agent, a disintegrant, a binder, and a filler;

[0010] The modified dispersant has a structure shown in the following formula A:

[0011] .

[0012] The present invention uses a combination of bicyclazone, oxadiazon, and quinclorac as the active ingredients of the pesticide. Bicyclazone, a broad-spectrum selective herbicide for weeds, is absorbed by the roots and stem bases of weeds and then transported to the entire plant, making it effective against perennial grasses, stubborn weeds, and sulfonylurea-resistant weeds. Oxadiazon is mainly absorbed by weed shoots, stems, and leaves and exerts good herbicidal activity in the presence of light, and is particularly sensitive to weeds in the budding stage. Once the weeds germinate, the growth of the sheaths is inhibited, their tissues rapidly rot, and the weeds die. Quinclorac is used to control barnyardgrass and has a long shelf life. The combination of the three can expand the control spectrum, enhance control efficacy, and delay weed resistance.

[0013] The modified dispersant is prepared by the following steps:

[0014] (1) Add 1-chloromethylnaphthalene, N,N'-dimethylethylenediamine and triethylamine into the reactor, heat to 80-95°C, reflux for 6-8 hours, cool and crystallize, filter, dry and set aside;

[0015] (2) Add the product of step (1), sodium chloroacetate and anhydrous ethanol into the reactor, stir and heat to 70-80°C, react for 4-6 hours, add water, filter, wash and dry to obtain the modified dispersant.

[0016] The modified dispersant added in the present invention is a Gemini-type surfactant, which contains two hydrophilic groups and two lipophilic groups in the molecule and has high surface activity. It can significantly reduce the surface tension of the product, so that the pesticide can be fully spread and retained on the target substance, thereby enhancing the dispersibility and suspension rate of the pesticide and thus improving its efficacy. The naphthalene ring structure in the molecule has good affinity with the active ingredients of the pesticide and has excellent stability, which can improve the stability of the preparation.

[0017] Furthermore, in step (1), the molar ratio of 1-chloromethylnaphthalene to N,N'-dimethylethylenediamine is 2.2-2.5:1.

[0018] Furthermore, in the step (2), the mass ratio of the product of step (1) to sodium chloroacetate is 1.5-2:1.

[0019] Furthermore, the wetting agent is selected from at least one of sodium lauryl sulfate, sodium butylnaphthalene sulfonate or sodium alkyl succinate sulfonate.

[0020] Furthermore, the disintegrant is selected from at least one of sodium tripolyphosphate, sodium carboxymethyl starch or microcrystalline cellulose.

[0021] Furthermore, the binder is selected from at least one of carboxymethyl cellulose, polyvinyl alcohol, polyvinyl pyrrolidone or sucrose.

[0022] Furthermore, the filler is selected from at least one of bentonite, kaolin, diatomaceous earth or white carbon black.

[0023] Furthermore, based on the total mass fraction being 100%, the mass percentage of each component is:

[0024] Bicyclazone 15-20%

[0025] Oxadiazon 10-15%

[0026] Quinclorac 1-5%

[0027] Modified dispersant 5-10%

[0028] Wetting agent 3-5%

[0029] Disintegrant 3-5%

[0030] Binder 1-3%

[0031] The balance is filler.

[0032] The method for preparing any one of the above-mentioned pesticide water-dispersible granules with excellent dispersibility comprises the following steps:

[0033] (1) Evenly mixing bicyclon, oxadiazon, quinclorac, a modified dispersant, and a disintegrant to obtain a mixed material;

[0034] (2) mixing the wetting agent, the binder and the water, and then mixing the mixture with the mixed material to obtain a suspension, and spray drying the suspension to obtain a mixture;

[0035] (3) After the mixture is mixed with the filler, the mixture is granulated by extrusion and dried to obtain the pesticide water-dispersible granules with excellent dispersibility.

[0036] In the present invention, the compounded active ingredient and the modified dispersant are used simultaneously. The modified dispersant having a naphthalene ring structure and excellent surface activity can enhance the dispersibility of the compounded active ingredient having a polycyclic structure and complex properties, thereby improving the efficacy of the pesticide.

[0037] Beneficial effects:

[0038] (1) The water-dispersible pesticide granules with excellent dispersibility provided by the present invention use a combination of cyclohexane, oxadiazon and dichloroquinoline as the active ingredients of the pesticide. Cyclohexane is a broad-spectrum selective herbicide for weeds. It is absorbed by the roots and stem bases of weeds and then transmitted to the entire plant. It is effective against perennial grasses, stubborn weeds and sulfonylurea-resistant weeds. Oxadiazon is mainly absorbed by weed buds and stems and leaves and can exert good herbicidal activity under light conditions. It is particularly sensitive to weeds in the budding stage. Once the weeds germinate, the growth of the bud sheath is inhibited, the tissue quickly rots, and the weeds die. Dichloroquinoline is used to control barnyardgrass and has a long applicable period. The combination of the three can expand the control spectrum, enhance the control effect, and delay the development of weed resistance.

[0039] (2) The modified dispersant is added to the pesticide water-dispersible granules with excellent dispersibility provided by the present invention. The modified dispersant is a Gemini-type surfactant, which contains two hydrophilic groups and two lipophilic groups in the molecule and has high surface activity. It can significantly reduce the surface tension of the product, so that the pesticide can be fully spread and retained on the target substance, thereby enhancing the dispersibility and suspension rate of the pesticide and thus improving its efficacy; the naphthalene ring structure in the molecule has good affinity with the active ingredients of the pesticide and has excellent stability, which can improve the stability of the preparation.

[0040] (3) The water-dispersible granules of the pesticide with excellent dispersibility provided by the present invention are prepared by using the compounded active ingredient and the modified dispersant simultaneously. The modified dispersant having a naphthalene ring structure and excellent surface activity can enhance the dispersibility of the compounded active ingredient having a polycyclic structure and complex characteristics, thereby improving the efficacy of the pesticide.

[0041] (4) The water-dispersible granules of the pesticide with excellent dispersibility provided by the present invention have excellent stability, dispersibility and suspension rate, and thus have excellent efficacy. DETAILED DESCRIPTION

[0042] The present invention will be described below in conjunction with specific embodiments. It should be noted that the following examples are illustrative of the present invention and are intended only to illustrate the present invention and are not intended to limit the present invention. Other combinations and various modifications within the scope of the present invention may be made without departing from the spirit or scope of the present invention.

[0043] The commercially available pesticide water-dispersible granules were 60% hexazinone diuron water-dispersible granules purchased from Hubei Phosphorus City Technology Co., Ltd.; the remaining reagents and equipment were conventional reagents and equipment in this technical field.

[0044] Modified dispersant-1 was prepared by the following steps:

[0045] (1) In a four-necked flask equipped with a spherical condenser, mechanical stirring, thermometer, and hollow stopper, add 0.1 mol of 1-chloromethylnaphthalene, 0.04 mol of N,N'-dimethylethylenediamine, and 100 mL of triethylamine, heat to 90°C, reflux for 8 hours, cool and crystallize, filter, and dry for later use;

[0046] (2) In a reactor, 10 g of the product of step (1), 5 g of sodium chloroacetate and 50 mL of anhydrous ethanol were added, stirred and heated to 80°C, reacted for 6 hours, and then filtered, washed and dried to obtain the modified dispersant-1.

[0047] Mass spectrometry data of modified dispersant-1: The product was analyzed by LC-MS, and the m / z of the product was 530.22 (100.0%), 531.24 (34.4%), and 532.24 (5.9%).

[0048] The preparation is basically the same as that of modified dispersant-1, except that 1-chloromethylnaphthalene is replaced with an equal amount of 1-chlorohexane. Example

[0049] The water-dispersible granules of pesticide with excellent dispersibility are prepared by the following steps:

[0050] (1) Evenly mixing bicyclon, oxadiazon, quinclorac, modified dispersant-1, and sodium tripolyphosphate to obtain a mixed material;

[0051] (2) mixing sodium lauryl sulfate, carboxymethyl cellulose and water, and then mixing with the mixed material to obtain a suspension, and spray-drying the suspension to obtain a mixture;

[0052] (3) mixing the mixture with bentonite, granulating the mixture by extrusion, and drying the mixture to obtain the pesticide water-dispersible granules with excellent dispersibility;

[0053] Taking the total mass fraction as 100%, the mass percentage of each component is:

[0054] Bicyclazone 15%

[0055] Oxadiazon 10%

[0056] Quinclorac 3%

[0057] Modified dispersant-1 5%

[0058] Sodium lauryl sulfate 3%

[0059] Sodium tripolyphosphate 3%

[0060] Carboxymethyl cellulose 1%

[0061] The balance is bentonite. Example

[0062] Basically the same as Example 1, except that based on the total mass being 100%, the components and their mass percentages are as follows:

[0063] Bicyclazone 17%

[0064] Oxadiazon 12%

[0065] Quinclorac 3%

[0066] Modified dispersant-1 8%

[0067] Sodium butylnaphthalenesulfonate 4%

[0068] Sodium carboxymethyl starch 4%

[0069] Polyvinyl alcohol 2%

[0070] The balance is kaolin. Example

[0071] Basically the same as Example 1, except that based on the total mass being 100%, the components and their mass percentages are as follows:

[0072] Bicyclazone 20%

[0073] Oxadiazon 15%

[0074] Quinclorac 5%

[0075] Modified dispersant-1 10%

[0076] Sodium alkyl succinate sulfonate 5%

[0077] Microcrystalline cellulose 5%

[0078] Polyvinylpyrrolidone 3%

[0079] The balance was diatomaceous earth.

[0080] Commercially available pesticide water dispersible granules.

[0081] The process is basically the same as Example 1, except that oxadiazon and quinclorac are replaced with equal amounts of bicyclon.

[0082] The process is basically the same as Example 1, except that the modified dispersant-1 is replaced by an equal amount of sodium lignin sulfonate.

[0083] The process is basically the same as Example 1, except that the modified dispersant-1 is replaced by an equal amount of modified dispersant-2.

[0084] Dispersibility test: According to the test method in GB / T32775-2016 "Determination of Dispersibility of Pesticides", the dispersibility of the products of Examples 1-3 and Comparative Examples 1-4 was tested.

[0085] Suspension rate detection: According to the determination method in GB / T14825-2006 "Determination of suspension rate of pesticides", the suspension rates of the products of Examples 1-3 and Comparative Examples 1-4 were detected.

[0086] Thermal Storage Stability Test: According to the test method specified in GB / T 19136-2003 "Thermal Storage Stability of Pesticides," approximately 5 g of each of Examples 1-3 and Comparative Examples 1-4 was sealed in a 50 ml ampoule and placed in a (54 ± 2) °C constant temperature oven. After 14 days, the suspension rate was measured.

[0087] Efficacy testing:

[0088] Target of control: Common grass weeds occurring in the field;

[0089] Application method: After rice seedlings have been transplanted and the weeds are in the vigorous growth stage with 3-5 leaves, spray evenly on the stems and leaves of the weeds;

[0090] Test investigation: Equal amounts of the products of Examples 1-3 and Comparative Examples 1-4 were applied to the field. 21 days after application, the five-point sampling method was used to weigh the aboveground fresh weight of the weeds in each plot according to the weed species, and the fresh weight control efficacy was calculated.

[0091] Fresh weight control effect E (%) = (1-weed mass in the treatment area / weed mass in the control area) × 100%

[0092] The test results are shown in the following table:

[0093] According to the comparison of the test results of Examples 1-3 and Comparative Example 1, it can be seen that the pesticide water-dispersible granules with excellent dispersibility provided by the present invention have excellent dispersibility and suspension rate, strong stability, and excellent efficacy.

[0094] According to the comparison of the test results of Examples 1-3 and Comparative Example 2, the water-dispersible granules of the pesticide with excellent dispersibility provided by the present invention can significantly enhance the efficacy of the pesticide by using a combination of bicyclon, oxadiazon and quinclorac as the active ingredients of the pesticide.

[0095] According to the comparison of the test results of Examples 1-3 with Comparative Examples 3 and 4, it can be seen that adding a modified dispersant to the pesticide water-dispersible granules with excellent dispersibility provided by the present invention can significantly improve the dispersibility and suspension of the pesticide and enhance the stability, thereby improving the efficacy of the pesticide granules.

[0096] The above embodiments are only for illustrating the technical concept and features of the present invention. Its purpose is to enable people familiar with this technology to understand the content of the present invention and implement it. It cannot be used to limit the scope of protection of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the scope of protection of the present invention.

Claims

1. A pesticide water-dispersible granule with excellent dispersibility, characterized in that: Contains bicyclon, oxadiazon, quinclorac, modified dispersant, wetting agent, disintegrant, binder and filler; The modified dispersant has a structure shown in the following formula A: ； The modified dispersant is prepared by the following steps: (1) Add 1-chloromethylnaphthalene, N,N'-dimethylethylenediamine and triethylamine into the reactor, heat to 80-95°C, reflux for 6-8 hours, cool and crystallize, filter, dry and set aside; (2) Add the product of step (1), sodium chloroacetate and anhydrous ethanol into the reactor, stir and heat to 70-80°C, react for 4-6 hours, add water, filter, wash and dry to obtain the modified dispersant.

2. The pesticide water dispersible granules with excellent dispersibility according to claim 1, characterized in that In the step (1), the molar ratio of 1-chloromethylnaphthalene to N,N'-dimethylethylenediamine is 2.2-2.5:

1.

3. The pesticide water dispersible granules with excellent dispersibility according to claim 1, characterized in that In the step (2), the mass ratio of the product of step (1) to sodium chloroacetate is 1.5-2:

1.

4. The pesticide water-dispersible granules with excellent dispersibility according to claim 1, characterized in that The wetting agent is selected from at least one of sodium lauryl sulfate, sodium butylnaphthalene sulfonate or sodium alkyl succinate sulfonate.

5. The pesticide water-dispersible granules with excellent dispersibility according to claim 1, characterized in that The disintegrant is selected from at least one of sodium tripolyphosphate, sodium carboxymethyl starch or microcrystalline cellulose.

6. The pesticide water dispersible granules with excellent dispersibility according to claim 1, characterized in that The binder is selected from at least one of carboxymethyl cellulose, polyvinyl alcohol, polyvinyl pyrrolidone or sucrose.

7. The pesticide water-dispersible granules with excellent dispersibility according to claim 1, characterized in that The filler is selected from at least one of bentonite, kaolin, diatomaceous earth or white carbon black.

8. The pesticide water-dispersible granules with excellent dispersibility according to claim 1, characterized in that Taking the total mass fraction as 100%, the mass percentage of each component is: Bicyclazone 15-20% Oxadiazon 10-15% Quinclorac 1-5% Modified dispersant 5-10% Wetting agent 3-5% Disintegrant 3-5% Binder 1-3% The balance is filler.

9. The method for preparing the pesticide water-dispersible granules with excellent dispersibility according to any one of claims 1 to 8, characterized in that: The following steps are involved: (1) Evenly mixing bicyclon, oxadiazon, quinclorac, a modified dispersant, and a disintegrant to obtain a mixed material; (2) mixing the wetting agent, the binder and the water, and then mixing the mixture with the mixed material to obtain a suspension, and spray drying the suspension to obtain a mixture; (3) After the mixture is mixed with the filler, the mixture is granulated by extrusion and dried to obtain the pesticide water-dispersible granules with excellent dispersibility.

Images