A high-performance pesticide water-dispersible granule and its preparation method

Abstract

This invention discloses a high-performance pesticide water-dispersible granule and its preparation method. The high-performance pesticide water-dispersible granule comprises pesticide active ingredients, compound synergists, binders, and fillers. The compound synergists are prepared by mixing a modified penetrant, fatty alcohol polyoxyethylene ether, and methyl oleate. The modified penetrant has the structure shown in Formula A. The high-performance pesticide water-dispersible granule provided by this invention, by adding compound synergists, can significantly reduce the surface tension of the pesticide water-dispersible granules on crops, improve its wettability and suspension rate, thereby improving the application effect. Furthermore, it can improve the stability and hard water resistance of the pesticide water-dispersible granules, expanding its application range.

Description

Technical Field

[0001] This invention relates to the field of pesticide formulation technology, specifically to a high-performance water-dispersible granule pesticide and its preparation method. Background Technology

[0002] Using pesticides to control pests, diseases, and weeds is an indispensable means of ensuring high-quality and high-yield agricultural products. Modern pesticide formulations are developing towards water-based, ultra-fine, dust-free, and controlled-release formulations. Known pesticide formulations include powders, granules, wettable powders, water-dispersible granules, liquid formulations, aqueous suspensions, emulsions, and many others. Among these formulations, water-dispersible granules, because they do not produce dust during application and reduce user exposure to pesticides, minimize environmental pollution during processing and use. Furthermore, they are convenient for measurement, packaging, and transportation, reducing costs for farmers and representing a major trend in pesticide development.

[0003] Water-dispersible granules of pesticides are a new type of environmentally friendly pesticide formulation developed in the 1980s. They are granular formulations that can rapidly disintegrate and disperse in water into a highly suspended solid-liquid dispersion system. Due to their advantages such as convenient use, no solvent required, no dust pollution, and high content of active ingredients, they have been rapidly developed.

[0004] Currently, water-dispersible granules mainly consist of active pharmaceutical ingredients (APIs), dispersants, wetting agents, disintegrants, binders, and fillers. The selection of adjuvants is a key factor affecting the wettability, disintegration, and suspension properties of water-dispersible granules, which in turn affects the amount of pesticide residue on the plant surface, the residence time, and the penetration ability of the pesticide into the plant epidermis, thus affecting the biological activity of the pesticide. Existing water-dispersible granule formulations are simple and sensitive to changes in raw materials. In particular, the performance of water-dispersible granules produced from the same API by different manufacturers using the same formulation can vary significantly. Therefore, it is necessary to research a high-performance pesticide water-dispersible granule to improve the utilization rate of pesticide active ingredients.

[0005] For pesticides to achieve high application efficiency, the pesticide solution must first be able to spread and remain fully on the target substance. This requires the pesticide solution to have low surface tension, thereby exhibiting good wetting and penetration on the target surface. Otherwise, pesticide loss will occur, inevitably affecting efficacy and causing serious environmental pollution. Furthermore, the stability and hard water resistance of existing pesticide water-dispersible granules still need improvement.

[0006] Therefore, there is an urgent need for a high-performance pesticide water-dispersible granule with strong wettability, high suspension rate, excellent stability, and resistance to hard water. Summary of the Invention

[0007] Purpose of the invention: In view of the deficiencies of the prior art, the purpose of this invention is to provide a high-performance pesticide water-dispersible granule with strong wettability, high suspension rate, excellent stability and hard water resistance, and its preparation method.

[0008] Technical solution:

[0009] A high-performance pesticide water-dispersible granule, comprising pesticide active ingredients, compound synergists, binders and fillers;

[0010] The compound synergist is prepared by mixing a modified penetrant, fatty alcohol polyoxyethylene ether, and methyl oleate.

[0011] The modified penetrant has the structure shown in Formula A:

[0012]

[0013] Furthermore, the active ingredient of the pesticide is selected from at least one of cyclomethonium, bicyclosulfuron, oxadiazon, abamectin, chlorantraniliprole, imidacloprid, or thiamethoxam.

[0014] Furthermore, the adhesive is selected from at least one of carboxymethyl cellulose, polyvinyl alcohol, polyvinylpyrrolidone, or sucrose.

[0015] Furthermore, the filler is selected from at least one of bentonite, kaolin, diatomite, or silica.

[0016] Furthermore, the mass ratio of the modified penetrant, fatty alcohol polyoxyethylene ether, and methyl oleate in the compound synergist is (6-8):(2-3):(1-2).

[0017] This invention incorporates a compound synergist. Through the combined use of a modified penetrant, fatty alcohol polyoxyethylene ether, and methyl oleate, the synergistic effect of these three components enhances the suspension rate of water-dispersible granules, maintains consistent pesticide concentration, and improves pesticide efficacy. Furthermore, it significantly reduces the surface tension and contact angle of pesticide droplets on crop surfaces, thereby increasing the wetting and spreading area of ​​the droplets, improving wettability, and ultimately enhancing pesticide efficacy and extending the effective period of the pesticide.

[0018] Furthermore, the modified penetrant is prepared through the following steps:

[0019] (1) Maleic anhydride, hydroxyhexyltrimethylsilane and catalyst are added to the reactor, and the temperature is raised to 80-90℃ under protective gas. After stirring for 10-12 hours, the intermediate is obtained by vacuum distillation.

[0020] (2) In a reactor, sodium bisulfite, intermediate, ethanol and water are added, heated to 95-105°C, stirred for 6-8 hours, cooled and recrystallized to obtain the modified penetrant.

[0021] The modified penetrant added to the compound synergist of the present invention has two advantages. First, based on its sulfonate surfactant structure, it has excellent surface activity. When mixed with fatty alcohol polyoxyethylene ether and methyl oleate, it can further improve the surface activity of the compound synergist and enhance the efficacy of pesticides. Second, through the silane groups in its structure, it can improve the dispersibility of the compound synergist, thereby increasing the suspension rate of water-dispersible granules, improving the stability and hard water resistance of the granules, and expanding the application range of the granules.

[0022] Furthermore, in step (1), the molar ratio of maleic anhydride to hydroxyhexyltrimethylsilane is 1:1.1-1.3; and the catalyst is p-toluenesulfonic acid.

[0023] Furthermore, in step (2), the mass ratio of sodium bisulfite to the intermediate is 1:3.5-4.

[0024] Furthermore, based on a total mass fraction of 100%, the mass percentage content of each component is as follows:

[0025] 40-50% of pesticide active ingredients

[0026] Compound synergist 10-15%

[0027] Adhesive 1-3%

[0028] The remainder is filler.

[0029] The preparation method of the above-mentioned high-performance pesticide water-dispersible granules includes the following steps:

[0030] (1) After mixing the pesticide active ingredients and compound synergist evenly, add binder and water, stir to obtain a suspension, and spray dry the suspension to obtain a mixture.

[0031] (2) The mixture is mixed with filler, and then granulated by extrusion and dried to obtain the high-performance pesticide water-dispersible granules.

[0032] Beneficial effects:

[0033] (1) The high-performance pesticide water-dispersible granules provided by the present invention contain pesticide active ingredients, compound synergists, binders and fillers. By adding compound synergists, the surface tension of pesticide water-dispersible granules on crops can be significantly reduced, and their wettability and suspension rate can be improved, thereby improving the application effect. On the other hand, the stability and hard water resistance of pesticide water-dispersible granules can be improved, and their application range can be expanded.

[0034] (2) The high-performance pesticide water-dispersible granules provided by the present invention are supplemented with compound synergists. Through the mixed use of modified penetrants, fatty alcohol polyoxyethylene ethers and methyl oleate, the three synergistic effects can, on the one hand, improve the suspension rate of water-dispersible granules and maintain the consistency of pesticide concentration through their excellent surface activity, thereby improving the pesticide effect; on the other hand, they can significantly reduce the surface tension and contact angle of pesticide droplets on the surface of crops, thereby increasing the wetting and spreading area of ​​droplets, improving wettability, and thus improving the pesticide efficacy and extending the effective period of the pesticide.

[0035] (3) The modified penetrant added to the compound synergist of the high-performance pesticide water-dispersible granules provided by the present invention has excellent surface activity ability based on its sulfonate surfactant structure. After being mixed with fatty alcohol polyoxyethylene ether and methyl oleate, the surface activity ability of the compound synergist can be further improved, thereby improving the efficacy of the pesticide. On the other hand, through the silane group in its structure, the dispersibility of the compound synergist can be improved, thereby improving the suspension rate of the water-dispersible granules, and improving the stability and hard water resistance of the granules, thus expanding the application range of the granules. Detailed Implementation

[0036] The present invention will be described below with reference to specific embodiments. It should be noted that the following embodiments are examples of the present invention and are used only to illustrate the invention, not to limit it. Other combinations and various modifications within the scope of the present invention can be made without departing from its spirit or scope.

[0037] The commercially available pesticide water-dispersible granules were 60% cyclomethazine diuron water-dispersible granules purchased from Jiangsu Dongbao Agrochemical Co., Ltd.; the remaining reagents and equipment were conventional reagents and equipment in this technical field.

[0038] Preparation of Modified Penetrant-1

[0039] Modified penetrant-1 was prepared by the following steps:

[0040] (1) In a three-necked flask equipped with a stirrer, a water separator and a condenser, add 0.1 mol of maleic anhydride, 0.12 mol of hydroxyhexyltrimethylsilane and 0.5 g of p-toluenesulfonic acid. Under nitrogen protection, heat to 85 °C, stir and react for 12 hours, then distill under reduced pressure to obtain the intermediate.

[0041] (2) In a three-necked flask equipped with a stirrer, thermometer and reflux condenser, add 2g sodium bisulfite, 8g intermediate, 20ml ethanol and 30ml water, heat to 100℃, stir and react for 8 hours, cool and recrystallize to obtain the modified penetrant-1.

[0042] Mass spectrometry data of modified penetrant-1: The product was analyzed by LC-MS, and the m / z of the product was 532.23 (100.0%), 533.38 (40.4%), 534.31 (15.4%), and 535.35 (3.7%).

[0043] Preparation of Modified Penetrant-2

[0044] The preparation method is basically the same as that of modified penetrant-1, except that hydroxyhexyltrimethylsilane is replaced with an equal amount of isooctyl alcohol.

[0045] Example 1

[0046] High-performance pesticide water-dispersible granules are prepared using the following steps:

[0047] (1) After mixing the pesticide active ingredients and compound synergist evenly, add carboxymethyl cellulose and water, stir to obtain a suspension, and spray dry the suspension to obtain a mixture.

[0048] (2) The mixture is mixed with bentonite, and then granulated by extrusion and dried to obtain the high-performance pesticide water-dispersible granules;

[0049] The compound synergist is a mixture of modified penetrant-1, fatty alcohol polyoxyethylene ether, and methyl oleate in a mass ratio of 6:2:1.

[0050] The active ingredient of the pesticide is obtained by mixing bicyclosulfuron and oxadiazon in a mass ratio of 3:1.

[0051] Based on a total mass fraction of 100%, the mass percentage of each component is as follows:

[0052] 45% active ingredient in pesticide

[0053] Compound synergist 12.5%

[0054] 2% carboxymethyl cellulose

[0055] The remainder is bentonite.

[0056] Example 2

[0057] The basic formula is the same as in Example 1, except that the compound synergist is a mixture of modified penetrant-1, fatty alcohol polyoxyethylene ether and methyl oleate in a mass ratio of 6:3:2.

[0058] The active ingredient in this pesticide is imidacloprid.

[0059] Based on a total mass fraction of 100%, the mass percentage of each component is as follows:

[0060] 40% active ingredient in pesticides

[0061] 10% compound synergist

[0062] 1% polyvinylpyrrolidone

[0063] The remainder is diatomaceous earth.

[0064] Example 3

[0065] The basic formula is the same as in Example 1, except that the compound synergist is a mixture of modified penetrant-1, fatty alcohol polyoxyethylene ether and methyl oleate in a mass ratio of 8:2:2.

[0066] The active ingredient of the pesticide is obtained by mixing abamectin and chlorantraniliprole in a mass ratio of 1:4.

[0067] Based on a total mass fraction of 100%, the mass percentage of each component is as follows:

[0068] 50% of the active ingredient in pesticides

[0069] 15% compound synergist

[0070] 3% polyvinyl alcohol

[0071] The balance is silica.

[0072] Comparative Example 1

[0073] Commercially available water-dispersible granules of pesticides.

[0074] Comparative Example 2

[0075] The basic formula is the same as in Example 1, except that the compound synergist is replaced with an equal amount of sodium dodecyl sulfonate.

[0076] Comparative Example 3

[0077] The formula is basically the same as in Example 1, except that the modified penetrant-1 in the compound synergist is replaced with an equal amount of sodium dodecyl sulfonate.

[0078] Comparative Example 4

[0079] The process is basically the same as in Example 1, except that modified penetrant-1 in the compound synergist is replaced with modified penetrant-2.

[0080] Performance testing

[0081] 1. Wetting property test: The wetting property of the products of Examples 1-3 and Comparative Examples 1-4 was tested according to the test standard of GB / T 5451-2001 "Test method for wettable powder of pesticide".

[0082] 2. Suspension rate test: The suspension rate of the products of Examples 1-3 and Comparative Examples 1-4 was tested according to the test method in GB / T14825-2006 "Determination of Suspension Rate of Pesticides".

[0083] 3. Hard water resistance test: According to the test method in GB / T14825-2006 "Determination of suspension rate of pesticides", the standard hard water was replaced with hard water with ten times the standard concentration, and the suspension rate of the products of Examples 1-3 and Comparative Examples 1-4 was tested.

[0084] 4. Thermal storage stability test: According to the requirements of GB / T19136-2003 "Determination method of thermal storage stability of pesticides", about 5g of the products of Examples 1-3 and Comparative Examples 1-4 were sealed in 50ml ampoules and placed in a constant temperature oven at (54±2)℃. After storage for 14 days, the suspension rate was tested.

[0085] The test results are shown in the table below:

[0086] Wettability (s) Suspension rate -1 (%) Suspension rate -2 (%) Suspension rate -3 (%) Example 1 10 98 95 92 Example 2 12 97 94 91 Example 3 10 98 94 91 Comparative Example 1 95 86 74 76 Comparative Example 2 78 89 81 73 Comparative Example 3 43 92 84 77 Comparative Example 4 32 94 87 82

[0087] According to the comparison of the test results of Examples 1-3 and Comparative Example 1, the high-performance pesticide water-dispersible granules provided by the present invention have better wettability and suspension rate than the pesticide water-dispersible granules in the prior art, and can significantly improve their hard water resistance and stability, thus having a wider range of applications.

[0088] According to the comparison of the test results of Examples 1-3 and Comparative Example 2, the addition of compound synergists to the high-performance pesticide water-dispersible granules provided by the present invention can improve the wettability and suspension rate of the pesticide water-dispersible granules, and also improve their hard water resistance and stability.

[0089] According to the comparison of the test results of Examples 1-3 and Comparative Examples 3 and 4, the modified penetrant in the high-performance pesticide water-dispersible granules provided by the present invention has excellent surface activity, and can further improve the surface activity of the compound synergist after being mixed with fatty alcohol polyoxyethylene ether and methyl oleate. On the other hand, through the silane group in its structure, it can improve the dispersibility of the compound synergist, thereby improving the suspension rate of the water-dispersible granules, and can also improve the stability and hard water resistance of the granules.

[0090] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it. They should not be used to limit the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A high-performance pesticide water-dispersible granule, characterized in that, Based on a total mass fraction of 100%, it contains 40-50% pesticide active ingredients, 10-15% compound synergist, 1-3% binder, and the remainder of filler; The active ingredient of the pesticide is selected from at least one of cyclomethonium, bicyclosulfuron, oxadiazon, abamectin, chlorantraniliprole, imidacloprid, or thiamethoxam; The compound synergist is prepared by mixing a modified penetrant, fatty alcohol polyoxyethylene ether, and methyl oleate. The mass ratio of modified penetrant, fatty alcohol polyoxyethylene ether and methyl oleate in the compound synergist is (6-8):(2-3):(1-2); The modified penetrant has the structure shown in Formula A: ； The modified penetrant is prepared by the following steps: (1) In a reactor, maleic anhydride, hydroxyhexyltrimethylsilane and catalyst are added, and the temperature is raised to 80-90°C under protective gas. After stirring for 10-12 hours, the intermediate is obtained by vacuum distillation. (2) In a reactor, sodium bisulfite, intermediate, ethanol and water are added, heated to 95-105°C, stirred for 6-8 hours, cooled and recrystallized to obtain the modified penetrant.

2. The high-performance pesticide water-dispersible granule according to claim 1, characterized in that, The binder is selected from at least one of carboxymethyl cellulose, polyvinyl alcohol, polyvinylpyrrolidone, or sucrose.

3. The high-performance pesticide water-dispersible granule according to claim 1, characterized in that, The filler is selected from at least one of bentonite, kaolin, diatomite, or silica.

4. The high-performance pesticide water-dispersible granules according to claim 1, characterized in that, In step (1), the molar ratio of maleic anhydride to hydroxyhexyltrimethylsilane is 1:1.1-1.3; the catalyst is p-toluenesulfonic acid.

5. The high-performance pesticide water-dispersible granules according to claim 1, characterized in that, In step (2), the mass ratio of sodium bisulfite to the intermediate is 1:3.5-4.

6. The method for preparing the high-performance pesticide water-dispersible granules according to any one of claims 1-5, characterized in that, Includes the following steps: (1) After mixing the active ingredients of pesticides and compound synergists evenly, add binder and water, stir to obtain a suspension, and spray dry the suspension to obtain a mixture. (2) The mixture is mixed with filler, and then granulated by extrusion and dried to obtain the high-performance pesticide water-dispersible granules.

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