Dispersible oil suspending agent containing pyriproxyfen and dinotefuran and preparation method thereof

Abstract

The invention relates to the technical field of pesticides, and particularly discloses a dispersible oil suspending agent containing pyriproxyfen and dinotefuran and a preparation method of the dispersible oil suspending agent. Through the synergistic effect of the dispersing agent, the emulsifying agent and the dispersing medium, the oil suspending agent is not prone to flocculation and sedimentation of pesticide particles when stored under the high-temperature condition, the particle size of the pesticide particles changes little in the storage process, and therefore the dinotefuran and the pyriproxyfen can be evenly dispersed into liquid medicine in the actual use process, and the oil suspending agent has the advantages that the oil suspending agent is environmentally friendly; and uniform pesticide application is realized in a spraying area range, so that full prevention and control of diseases and pests are facilitated.

Description

Technical Field

[0001] The present application relates to the technical field of pesticides, and more specifically, to a dispersible oil suspension containing pyriproxyfen and dinotefuran and a preparation method thereof. Background Art

[0002] Dispersible oil suspensions (ODs) are highly dispersed suspensions formed by dispersing solid pesticide active ingredients that are insoluble in oil solvents in a non-aqueous medium (i.e., oils) using surfactants. These formulations typically need to be diluted with water before use. The oil carriers used in ODs typically have good adhesion and spreadability, easily adhering to waxy or smooth leaf surfaces and forming a film on plants or targets after spraying. According to the principle of like dissolves like, the resulting solution has strong penetration and conductivity, good adhesion, resistance to rain erosion, and a high utilization rate of the active ingredients. These solutions can more fully exert their efficacy and are more environmentally friendly than traditional pesticides.

[0003] Dinotefuran is currently the only neonicotinoid insecticide containing a tetrahydrofuran ring. It boasts a broad insecticide spectrum, high activity, rapid efficacy, and long-lasting effects. It also exhibits contact, stomach, and root systemic activity. It is highly effective against piercing-sucking pests and is primarily used to control Hemiptera, Lepidoptera, Caraboptera, Diptera, Orthoptera, and Hymenoptera pests on crops such as rice, vegetables, and fruits. Pyriproxyfen, also known as pyriproxyfen and pyriproxyfen, is chemically known as 4-phenoxyphenyl-(RS)-2-(2-pyridyloxy)propyl ether. It is a chitin synthesis inhibitor of the alkoxypyridine juvenile hormone class, first developed by Sumitomo Chemical in Japan in 1983 and commercialized in 1991. Pyriproxyfen is widely used to control whiteflies and scale insects. Its advantages include good photostability, low dosage, high activity, strong leaf conductivity and systemic uptake, long-lasting effect, crop safety, low toxicity to mammals, and minimal impact on the ecological environment, all in line with human goals of protecting the ecological environment. By combining pyriproxyfen and dinotefuran into an oil suspension concentrate, the advantages of both can be combined to achieve higher insecticide efficiency.

[0004] With respect to the above-mentioned related technologies, the inventors believe that although the oil suspension concentrate with pyriproxyfen and dinotefuran as active ingredients can theoretically exert a good insecticidal effect, the oil suspension concentrate is prone to flocculation and sedimentation after being left standing for a period of time in a high-temperature environment, resulting in uneven distribution of the formulation ingredients. In actual use, it is easy to cause insufficient pesticide coverage in local areas, which is not conducive to fully achieving pest control. Summary of the Invention

[0005] In related technologies, oil suspension concentrates (OSCs) are prone to flocculation and sedimentation after standing for a period of time in a high-temperature environment, resulting in uneven distribution of the formulation ingredients. This can easily lead to insufficient pesticide coverage in localized areas during actual use, hindering effective pest control. To address this shortcoming, the present application provides a dispersible oil suspension concentrate containing pyriproxyfen and dinotefuran, and a method for preparing the same.

[0006] In a first aspect, the present application provides a dispersible oil suspension concentrate containing pyriproxyfen and dinotefuran, which adopts the following technical solution: A dispersible oil suspension containing pyriproxyfen and dinotefuran comprises the following components by weight: 12-15% pyriproxyfen, 3-5% dinotefuran, 10-12% dispersant, 20-25% emulsifier, 1.5-2.5% wetting agent, 0.5-0.8% tackifier, 0.5-0.8% stabilizer, with the remainder being supplemented to 100% by a dispersion medium; the dispersant comprises polyethylene glycol fatty acid ester, the dispersion medium comprises methyl oleate and rosin-based vegetable oil, and the emulsifier comprises terpene disodium salt.

[0007] By adopting the above technical solution, the present application optimizes the specific components of the dispersant, dispersion medium and emulsifier, selects polyethylene glycol fatty acid ester as the dispersant, selects terpene disodium salt as the emulsifier, and limits the dispersion medium to include rosin-based vegetable oil. Polyethylene glycol fatty acid ester contains hydrophilic polyethylene glycol segments and hydrophobic fatty acid segments, and terpene disodium salt contains hydrophobic terpene skeleton and hydrophilic active groups, both of which have certain amphiphilicity. Under the synergistic cooperation of polyethylene glycol fatty acid ester and terpene disodium salt, a protective film can be formed on the surface of the pesticide particles of pyriproxyfen and dinotefuran. The protective film achieves isolation between the pesticide particles through charge effect and steric hindrance effect, reducing contact and flocculation between the pesticide particles. In the dispersion medium of the present application, rosin-based vegetable oil contains fatty acid segments similar to polyethylene glycol fatty acid ester on the one hand, and is similar in structure to terpene disodium salt on the other hand, thus promoting the uniform dispersion of pesticide particles in the dispersion medium through the principle of similar compatibility. Due to the synergistic effect of the above-mentioned dispersant, emulsifier, and dispersion medium, the oil suspension concentrate of the present application is not prone to flocculation and sedimentation of pesticide particles when stored under high temperature conditions, and the particle size of the pesticide particles changes little during storage. Therefore, in actual use, dinotefuran and pyriproxyfen can be evenly dispersed in the liquid medicine, and uniform application of the medicine can be achieved within the spraying area, which is conducive to fully achieving pest control.

[0008] Preferably, the terpene disodium salt is prepared according to the following method: (1) using ethanol to purify the disproportionated rosin to obtain dehydroabietic acid, mixing the dehydroabietic acid with concentrated sulfuric acid under ice-salt bath conditions, adding ice water after the reaction, and then filtering and washing, and then recrystallizing and filtering twice to obtain sulfonated dehydroabietic acid; (2) Sulfonated dehydroabietic acid and sodium hydroxide solution are mixed, filtered after the reaction is completed, and then allowed to stand and recrystallize to obtain terpene disodium salt.

[0009] By adopting the above technical solution, the present application preferably provides a method for preparing terpene disodium salt. The above method first uses ethanol to remove impurities in the disproportionated rosin to obtain relatively pure dehydroabietic acid, then sulfonates the dehydroabietic acid, and finally reacts sodium hydroxide with the sulfonated dehydroabietic acid to obtain terpene disodium salt.

[0010] Preferably, the emulsifier further comprises cetyltrimethylammonium bromide.

[0011] By adopting the above technical solution, terpene disodium salt and cetyltrimethylammonium bromide have good compatibility, can achieve synergistic dispersion, reduce flocculation and sedimentation of pesticide particles, and help enhance the high temperature stability of the oil suspension.

[0012] Preferably, the dispersant further comprises a multi-polymer PCA dispersant, wherein the multi-polymer PCA dispersant is copolymerized by monomers including polyether macromonomer, acrylate and styrene, and the polyether macromonomer comprises allyl alcohol polyoxyethylene ether.

[0013] By adopting the above technical solution, the present application uses polyether macromonomers, acrylates and styrene to prepare a multi-polymer PCA dispersant. In the multi-polymer PCA dispersant, the structural unit formed by the polyether macromonomer can provide a large steric hindrance and has a high compatibility with the polyether segment in the polyethylene glycol fatty acid ester; the structural unit formed by the acrylate has a high compatibility with the fatty acid segment in the rosin-based vegetable oil and the polyethylene glycol fatty acid ester; the benzene ring structure introduced by styrene has a high compatibility with the terpene disodium salt and the aromatic group in the rosin-based vegetable oil. The multi-polymer PCA dispersant effectively reduces the flocculation and sedimentation of pesticide particles through the synergistic effect with the polyethylene glycol fatty acid ester, the rosin-based vegetable oil and the terpene disodium salt, thereby helping to enhance the high temperature stability of the oil suspension.

[0014] Preferably, the polyether macromonomer further comprises a maleic anhydride grafted polyether, and the maleic anhydride grafted polyether is prepared according to the following method: Nonylphenol polyoxyethylene ether and maleic anhydride are mixed, and p-toluenesulfonic acid is added as a catalyst. After stirring and heating, the mixture is kept warm for reaction, and then cooled and discharged to obtain maleic anhydride grafted polyether.

[0015] By adopting the above-mentioned technical solution, the present application uses maleic anhydride to modify nonylphenol polyoxyethylene ether to obtain a maleic anhydride grafted polyether containing unsaturated bonds. The maleic anhydride grafted polyether can synergistically enhance the steric hindrance effect of the multi-polymer PCA dispersant with allyl alcohol polyoxyethylene ether, effectively reducing the flocculation and sedimentation of pesticide particles, thereby helping to enhance the high-temperature stability of the oil suspension concentrate.

[0016] Preferably, the multi-polymer PCA dispersant is prepared according to the following method: (1) adding a polyether macromonomer to methyl oleate and dispersing it to obtain a macromonomer solution, which is set aside; adding styrene and acrylate to methyl oleate and dispersing it to obtain a small monomer solution, which is set aside; adding an initiator to toluene and dispersing it to obtain an initiator solution, which is set aside; (2) Adding the small monomer solution and the initiator solution to the large monomer solution under oil bath heating conditions, continuing to keep the temperature for reaction after the addition is completed, removing the toluene under reduced pressure after the reaction is completed, then cooling, and adding triethanolamine for neutralization to obtain a multi-polymer PCA dispersant.

[0017] By adopting the above technical solution, the present application first separately prepared a macromonomer solution, a small monomer solution and an initiator solution, and then carried out a copolymerization reaction with the macromonomer solution as the main body to obtain a multi-component copolymer PCA dispersant.

[0018] Preferably, the acrylate includes lauryl acrylate.

[0019] By adopting the above technical solution, lauryl acrylate has high compatibility with rosin-based vegetable oil and fatty acid segments in polyethylene glycol fatty acid esters, which helps to enhance the high-temperature stability of the oil suspension.

[0020] Preferably, in step (1) of preparing the multi-polymer PCA dispersant, linolenic acid is also added to methyl oleate when preparing the small monomer solution.

[0021] By adopting the above technical solution, multiple double bonds of linolenic acid can form branches at different positions respectively. The increase in the number of branches can enhance the steric hindrance effect of the multi-polymer PCA dispersant, which helps to enhance the high temperature stability of the oil suspension.

[0022] Preferably, the tackifier is organic bentonite, which is prepared according to the following method: Sodium bentonite is sieved and added to deionized water to obtain a bentonite suspension. Dodecyldimethylbenzyl ammonium chloride is added to the bentonite suspension under water bath heating conditions. After stirring and reacting, the mixture is cooled. The product is then centrifuged and the resulting precipitate is washed, centrifuged, dried, and crushed in sequence to obtain organic bentonite.

[0023] By adopting the above technical solution, the organic bentonite of the present application can play a viscosity-increasing role in the oil suspension concentrate and increase the yield value of the oil suspension concentrate, thereby making the oil suspension concentrate have strong shear thinning and pseudoplastic characteristics, hindering the flocculation and sedimentation of pesticide particles. The dodecyl group therein has a high compatibility with the fatty acid chain segments in rosin-based vegetable oil and polyethylene glycol fatty acid ester, thereby improving the high-temperature stability of the oil suspension concentrate.

[0024] In a second aspect, the present application provides a method for preparing a dispersible oil suspension containing pyriproxyfen and dinotefuran, which adopts the following technical solution.

[0025] A method for preparing a dispersible oil suspension containing pyriproxyfen and dinotefuran, comprising the following steps: (1) mixing a dispersion medium, an emulsifier, and a dispersant, performing shearing processing using a dispersion sand mill, and then adding pyriproxyfen, dinotefuran, a wetting agent, a tackifier, and a stabilizer, and continuing to perform shearing sand milling to obtain a semi-finished product; (2) The semi-finished product is transferred to a vertical sand mill for further sand grinding to obtain a dispersible oil suspension containing pyriproxyfen and dinotefuran.

[0026] By adopting the above technical solution, the present application first prepared the semi-finished product in steps in a dispersion sand mill, and then further processed it using a vertical sand mill to obtain a dispersible oil suspension containing pyriproxyfen and dinotefuran with stable performance and high temperature storage resistance.

[0027] In summary, this application has the following beneficial effects: 1. Through the synergistic effect of the dispersant, emulsifier, and dispersion medium, the oil suspension concentrate of the present application is not prone to flocculation and sedimentation of pesticide particles when stored under high temperature conditions. The particle size of the pesticide particles changes little during storage. Therefore, in actual use, dinotefuran and pyriproxyfen can be evenly dispersed in the liquid medicine, and uniform application of the pesticide can be achieved within the spraying area, which is conducive to fully achieving pest control.

[0028] 2. This application uses polyether macromonomers, acrylates and styrene to prepare a multi-polymer PCA dispersant. The multi-polymer PCA dispersant effectively reduces the flocculation and sedimentation of pesticide particles through the synergistic effect with polyethylene glycol fatty acid esters, rosin-based vegetable oils and terpene disodium salts, thereby helping to enhance the high-temperature stability of the oil suspension concentrate.

[0029] 3. The organic bentonite prepared in this application can play a viscosity-increasing role in the oil suspension concentrate and increase the yield value of the oil suspension concentrate, thereby making the oil suspension concentrate have strong shear thinning and pseudoplastic characteristics, hindering the flocculation and sedimentation of pesticide particles, and improving the high-temperature stability of the oil suspension concentrate. DETAILED DESCRIPTION

[0030] The present application is further described in detail below with reference to the Examples, Preparation Examples and Comparative Examples. The raw materials involved in the present application can all be obtained commercially.

[0031] Preparation Example of Terpene Disodium Salt The following is an explanation using Preparation Example 1.

[0032] Preparation Example 1 In this preparation example, terpene disodium salt was prepared according to the following method: (1) using 95% pure ethanol to purify the disproportionated rosin, and obtaining dehydroabietic acid after three recrystallizations. 10 g of dehydroabietic acid and 40 mL of concentrated sulfuric acid (98.3 wt%) were mixed in an ice-salt bath at 0° C. After the reaction, 100 mL of ice water was added, followed by filtration and washing, and then recrystallization and secondary filtration to obtain sulfonated dehydroabietic acid; (2) Sulfonated dehydroabietic acid and sodium hydroxide solution are mixed, fully reacted, filtered, and then allowed to stand and recrystallized to obtain terpene disodium salt.

[0033] Preparation Example of Multi-polymer PCA Dispersant The following is an illustration of Preparation Example 2.

[0034] Preparation Example 2 In this preparation example, the polyether macromonomer is allyl alcohol polyoxyethylene ether (APEG-1000), the acrylate is methyl acrylate, and the initiator is azobisisobutyronitrile.

[0035] In this preparation example, the multi-polymer PCA dispersant was prepared according to the following method: (1) Add 0.08 mol g of polyether macromonomer to 15 mL of methyl oleate and disperse to obtain a macromonomer solution, which is set aside; add 0.10 mol of styrene and 0.05 mol of acrylate to 35 mL of methyl oleate and disperse to obtain a small monomer solution, which is set aside; add 0.8 g of initiator to 5 mL of toluene and disperse to obtain an initiator solution, which is set aside; (2) Add the small monomer solution and the initiator solution to the large monomer solution under the condition of oil bath heating at 75°C. After 2 hours of addition, continue to keep warm and react for 4 hours. After the reaction is completed, remove toluene under reduced pressure at 95°C, then cool to 50°C, add triethanolamine for neutralization, and adjust the pH to 7.0 to obtain a multi-polymer PCA dispersant.

[0036] Preparation Example 3 The difference between this preparation example and preparation example 2 is that the polyether macromonomer is prepared by mixing allyl alcohol polyoxyethylene ether and maleic anhydride grafted polyether in a molar ratio of 3:5, and the maleic anhydride grafted polyether is prepared according to the following method: Mix 0.12 mol of nonylphenol polyoxyethylene ether and 0.10 mol of maleic anhydride, add 0.5 g of p-toluenesulfonic acid as a catalyst, stir and heat to 110°C, then keep the temperature for reaction for 2 hours, then cool to 50°C and discharge to obtain maleic anhydride grafted polyether.

[0037] Preparation Example 4 The difference between this preparation example and preparation example 3 is that methyl acrylate is replaced by dodecyl acrylate with the same molar number.

[0038] Preparation Example 5 The difference between this preparation example and preparation example 4 is that in step (1) of preparing the multi-polymer PCA dispersant, linolenic acid is also added to methyl oleate when preparing the small monomer solution, and the molar ratio of linolenic acid to acrylate is 1:10.

[0039] Preparation example of organobentonite The following is an illustration of Preparation Example 6.

[0040] Preparation Example 6 In this preparation example, organobentonite was prepared according to the following method: Sodium bentonite is passed through a 44 μm sieve and added to deionized water to prepare a bentonite suspension with a bentonite content of 50 wt%. Dodecyldimethylbenzylammonium chloride, equivalent in weight to half the sodium bentonite, is added to the bentonite suspension under water bath heating conditions. After stirring for 2 hours and then cooling, the product is centrifuged at a rate of 4000 r / min. The resulting precipitate is washed, centrifuged, dried and crushed in sequence, and passed through a 44 μm sieve to obtain organic bentonite. Example

[0041] Examples 1-3 The following description will be made using Example 1 as an example.

[0042] Example 1 In this embodiment, the dispersant is polyethylene glycol fatty acid ester (polyethylene glycol 400 dioleate), the dispersion medium is composed of methyl oleate and rosin-based vegetable oil (ND-45) mixed in a weight ratio of 3:1, the emulsifier is composed of the terpene disodium salt of Preparation Example 1 and Solvay agricultural surfactant (Geronol VO / 01) mixed in a weight ratio of 1:3; the wetting agent is Pluronic PE10500, the tackifier is fumed silica, and the stabilizer is butylated hydroxytoluene.

[0043] This embodiment provides a dispersible oil suspension containing pyriproxyfen and dinotefuran, which includes the following components in weight percentage: 12% pyriproxyfen, 3% dinotefuran, 10% dispersant, 20% emulsifier, 1.5% wetting agent, 0.5% tackifier, 0.5% stabilizer, and the balance is made up to 100% by dispersion medium.

[0044] This embodiment provides a method for preparing a dispersible oil suspension concentrate containing pyriproxyfen and dinotefuran, comprising the following steps: (1) mixing a dispersion medium, an emulsifier, and a dispersant, and shearing and processing the mixture using a dispersion sand mill for 5 minutes, then adding pyriproxyfen, dinotefuran, a wetting agent, a tackifier, and a stabilizer, and continuing shearing and sand milling for 10 minutes to obtain a semi-finished product; (2) The semi-finished product was transferred to a vertical sand mill and sand-milled for 2 h to obtain a dispersible oil suspension containing pyriproxyfen and dinotefuran with an average particle size of 2 μm.

[0045] As shown in Table 1, the main difference between Examples 1-3 is that the raw material ratios of the dispersible oil suspension are different.

[0046] Table 1 Ratio of raw materials for dispersible oil suspension Example 4 The difference between this embodiment and embodiment 3 is that the emulsifier further includes cetyltrimethylammonium bromide, and the weight ratio of cetyltrimethylammonium bromide to terpene disodium salt is 1:1.

[0047] Example 5 The difference between this embodiment and embodiment 4 is that the dispersant further includes a multi-polymer PCA dispersant, the multi-polymer PCA dispersant is prepared according to the method of preparation example 2, and the weight ratio of the multi-polymer PCA dispersant to the polyethylene glycol fatty acid ester is 1.5:1.

[0048] Example 6 The difference between this embodiment and embodiment 5 is that the multi-polymerized PCA dispersant is prepared according to the method of preparation example 3.

[0049] Example 7 The difference between this embodiment and embodiment 5 is that the multi-polymerized PCA dispersant is prepared according to the method of preparation example 4.

[0050] Example 8 The difference between this embodiment and embodiment 5 is that the multi-polymerized PCA dispersant is prepared according to the method of preparation example 5.

[0051] Example 9 The difference between this embodiment and embodiment 8 is that in the method for preparing the multi-polymerized PCA dispersant, lauryl acrylate is replaced by methyl acrylate.

[0052] Example 10 The difference between this embodiment and embodiment 8 is that the organic bentonite of preparation example 6 is used as the viscosity enhancer.

[0053] Comparative Example Comparative Example 1 In this comparative example, the dispersant was prepared by mixing SK-34SC dispersant and Dow D305 dispersant in a weight ratio of 13:5, the dispersion medium was first-grade soybean oil, the emulsifier was Solvay agricultural surfactant (Geronol VO / 01), the wetting agent was Pluronic PE10500, the tackifier was fumed silica, and the stabilizer was butylated hydroxytoluene.

[0054] This comparative example provides a dispersible oil suspension containing pyriproxyfen and dinotefuran, which includes the following components in weight percentage: 12% pyriproxyfen, 3% dinotefuran, 10% dispersant, 20% emulsifier, 1.5% wetting agent, 0.5% tackifier, 0.5% stabilizer, and the balance is supplemented to 100% by dispersion medium.

[0055] This comparative example provides a method for preparing a dispersible oil suspension concentrate containing pyriproxyfen and dinotefuran, comprising the following steps: (1) mixing a dispersion medium, an emulsifier, and a dispersant, and shearing and processing the mixture using a dispersion sand mill for 5 minutes, then adding pyriproxyfen, dinotefuran, a wetting agent, a tackifier, and a stabilizer, and continuing shearing and sand milling for 10 minutes to obtain a semi-finished product; (2) The semi-finished product was transferred to a vertical sand mill and sand-milled for 2 h to obtain a dispersible oil suspension containing pyriproxyfen and dinotefuran with an average particle size of 2 μm.

[0056] Comparative Example 2 This comparative example differs from Example 1 in that the dispersion medium only includes methyl oleate.

[0057] Comparative Example 3 This comparative example differs from Example 1 in that the emulsifier only includes Solvay agricultural surfactant (Geronol VO / 01).

[0058] Comparative Example 4 The difference between this comparative example and Example 1 is that the dispersant is a mixture of SK-34SC dispersant and Dow D305 dispersant in a weight ratio of 13:5.

[0059] Performance testing methods According to the test method described in "GB / T 19136-2021 Determination of Thermal Storage Stability of Pesticides," each group of oil suspension concentrates was stored in a constant temperature oven at 55°C for 14 days. The particle size before and after the test was measured using a laser particle size analyzer. Each test was repeated three times, and the average value was taken. After the test, the ratio of the post-test particle size to the pre-test particle size was calculated and recorded as the particle size growth ratio. The results are shown in Table 2.

[0060] Table 2 Particle size growth ratio sample Particle size growth ratio Example 1 1.74 Example 2 1.73 Example 3 1.71 Example 4 1.67 Example 5 1.59 Example 6 1.57 Example 7 1.54 Example 8 1.49 Example 9 1.53 Example 10 1.44 Comparative Example 1 2.38 Comparative Example 2 2.17 Comparative Example 3 2.04 Comparative Example 4 1.92 In conjunction with Examples 1-3 and Comparative Example 1 and in conjunction with Table 2, it can be seen that the particle size growth ratio measured in Examples 1-3 is relatively small. This is because both polyethylene glycol fatty acid ester and terpene disodium salt possess certain amphiphilicity. Under the synergistic cooperation of the two, the particle surface of pyriproxyfen and dinotefuran can form a protective film, which achieves isolation between pesticide particles through charge effect and steric hindrance effect, reducing contact and flocculation between pesticide particles. The preferred rosin-based vegetable oil of the present application contains fatty acid segments similar to polyethylene glycol fatty acid esters on the one hand, and is similar in structure to terpene disodium salt on the other hand, thereby being able to promote the uniform dispersion of pesticide particles in the dispersion medium through the similar compatibility principle. However, Comparative Example 1 cannot achieve the above-mentioned synergistic effect, and thus flocculation and sedimentation phenomena occur in the pesticide particles, resulting in a larger increase in particle size during high temperature storage.

[0061] Combining Example 1 and Comparative Example 2 with Table 2, it can be seen that the particle size growth ratio measured in Example 1 is relatively small. This is because Comparative Example 2 lacks rosin-based vegetable oil, and thus the compatibility between the dispersion medium and the emulsifier is limited. The emulsifier alone cannot fully assist in the dispersion of the pesticide particles, and thus the particle size of the pesticide particles increases significantly during high-temperature storage.

[0062] Combining Example 1 and Comparative Example 3 with Table 2, it can be seen that the particle size growth ratio measured in Example 1 is relatively small. This is because Comparative Example 3 lacks terpene disodium salt and cannot promote the uniform dispersion of pesticide particles through synergistic effects with polyethylene glycol fatty acid esters and rosin-based vegetable oils. As a result, the particle size of the pesticide particles increases significantly during high-temperature storage.

[0063] Combining Example 1 and Comparative Example 4 with Table 2, it can be seen that the particle size growth ratio measured in Example 1 is relatively small. This is because Comparative Example 4 lacks polyethylene glycol fatty acid ester, which cannot promote the uniform dispersion of pesticide particles through synergistic effects with terpene disodium salt and rosin-based vegetable oil. As a result, the particle size of the pesticide particles increases significantly during high-temperature storage.

[0064] Combining Examples 3 and 4 with Table 2, it can be seen that the particle size growth ratio measured in Example 4 is relatively small. This is because the terpene disodium salt and cetyltrimethylammonium bromide have good compatibility and can achieve a synergistic dispersion effect, thereby reducing flocculation and sedimentation of the pesticide particles, and helping to enhance the high temperature stability of the oil suspension concentrate.

[0065] Combining Example 4 and Example 5 with Table 2, it can be seen that the particle size growth ratio measured in Example 5 is relatively small. This is because the multi-polymerized PCA dispersant effectively reduces the flocculation and sedimentation of the pesticide particles through the synergistic effect with the polyethylene glycol fatty acid ester, rosin-based vegetable oil and terpene disodium salt, thereby helping to enhance the high temperature stability of the oil suspension concentrate.

[0066] Combining Examples 5 and 6 with Table 2, it can be seen that the particle size growth ratio measured in Example 6 is relatively small. This is because the maleic anhydride grafted polyether can synergistically enhance the steric hindrance effect of the multi-polymerized PCA dispersant with allyl alcohol polyoxyethylene ether, effectively reducing the flocculation and sedimentation of the pesticide particles, thereby helping to enhance the high temperature stability of the oil suspension concentrate.

[0067] From Example 6 and Example 7 and Table 2, it can be seen that the particle size growth ratio measured in Example 7 is relatively small. This is because lauryl acrylate has a high compatibility with the fatty acid segments in rosin-based vegetable oil, methyl oleate, and polyethylene glycol fatty acid esters, which helps to enhance the high temperature stability of the oil suspension concentrate.

[0068] Combining Example 7 and Example 8 with Table 2, it can be seen that the particle size growth ratio measured in Example 8 is relatively small. This is because the multiple double bonds of linolenic acid can form side chains respectively. The increase in the number of side chains can enhance the steric hindrance effect of the multi-polymerized PCA dispersant, which helps to enhance the high temperature stability of the oil suspension concentrate.

[0069] Combining Example 8, Example 9 and Table 2, it can be seen that in the absence of lauryl acrylate, even if linolenic acid is added, the high-temperature stability of the oil suspension concentrate cannot be fully enhanced, and the final measured result still has a certain gap with Example 8.

[0070] Combining Examples 8 and 10 with Table 2, it can be seen that the particle size growth ratio measured in Example 10 is relatively small. This is because the organobentonite of the present application can play a viscosity-increasing role in the oil suspension concentrate and increase the yield value of the oil suspension concentrate, thereby giving the oil suspension concentrate strong shear thinning and pseudoplastic characteristics, hindering the flocculation and sedimentation of the pesticide particles, and improving the high temperature stability of the oil suspension concentrate.

[0071] The above embodiments are merely explanations of the present application and are not limitations of the present application. After reading this specification, those skilled in the art may make modifications to the embodiments of the present application as needed without any creative contribution. However, as long as they are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A dispersible oil suspension concentrate containing pyriproxyfen and dinotefuran, characterized in that: The invention comprises the following components in percentage by weight: 12-15% of pyriproxyfen, 3-5% of dinotefuran, 10-12% of a dispersant, 20-25% of an emulsifier, 1.5-2.5% of a wetting agent, 0.5-0.8% of a tackifier, and 0.5-0.8% of a stabilizer, with the remainder being made up to 100% by a dispersion medium; the dispersant comprises polyethylene glycol fatty acid ester, the dispersion medium comprises methyl oleate and rosin-based vegetable oil, and the emulsifier comprises terpene disodium salt.

2. The dispersible oil suspension concentrate containing pyriproxyfen and dinotefuran according to claim 1, characterized in that The terpene disodium salt is prepared as follows: (1) Using ethanol to purify the disproportionated rosin to obtain dehydroabietic acid, the dehydroabietic acid and concentrated sulfuric acid are mixed under ice-salt bath conditions, ice water is added after the reaction is completed, and then the mixture is filtered and washed, and then recrystallized and filtered twice to obtain sulfonated dehydroabietic acid; (2) Sulfonated dehydroabietic acid and sodium hydroxide solution are mixed, filtered after the reaction is completed, and then allowed to stand and recrystallize to obtain terpene disodium salt.

3. The dispersible oil suspension concentrate containing pyriproxyfen and dinotefuran according to claim 2, characterized in that The emulsifier also includes cetyltrimethylammonium bromide.

4. The dispersible oil suspension concentrate containing pyriproxyfen and dinotefuran according to claim 1, characterized in that The dispersant also includes a multi-polymer PCA dispersant, which is formed by copolymerizing monomers including polyether macromonomers, acrylates and styrene, and the polyether macromonomers include allyl alcohol polyoxyethylene ether.

5. The dispersible oil suspension concentrate containing pyriproxyfen and dinotefuran according to claim 4, characterized in that The polyether macromonomer further comprises a maleic anhydride grafted polyether, and the maleic anhydride grafted polyether is prepared according to the following method: Nonylphenol polyoxyethylene ether and maleic anhydride are mixed, and p-toluenesulfonic acid is added as a catalyst. After stirring and heating, the mixture is kept warm for reaction, and then cooled and discharged to obtain maleic anhydride grafted polyether.

6. The dispersible oil suspension concentrate containing pyriproxyfen and dinotefuran according to claim 4, characterized in that The multi-polymer PCA dispersant is prepared as follows: (1) Adding a polyether macromonomer to methyl oleate and dispersing it to obtain a macromonomer solution, which is set aside; adding styrene and acrylate to methyl oleate and dispersing it to obtain a small monomer solution, which is set aside; adding an initiator to toluene and dispersing it to obtain an initiator solution, which is set aside; (2) Add the small monomer solution and the initiator solution to the large monomer solution under oil bath heating conditions. Continue to keep the temperature for reaction. After the reaction is completed, remove the toluene under reduced pressure, then cool down, and add triethanolamine for neutralization to obtain a multi-polymer PCA dispersant.

7. The dispersible oil suspension concentrate containing pyriproxyfen and dinotefuran according to claim 4, characterized in that The acrylic acid ester includes lauryl acrylate.

8. The dispersible oil suspension concentrate containing pyriproxyfen and dinotefuran according to claim 7, characterized in that In step (1) of preparing the multi-polymer PCA dispersant, linolenic acid is also added to methyl oleate when preparing the small monomer solution.

9. The dispersible oil suspension concentrate containing pyriproxyfen and dinotefuran according to claim 8, characterized in that The tackifier is organic bentonite, which is prepared according to the following method: Sodium bentonite is sieved and added to deionized water to obtain a bentonite suspension. Dodecyldimethylbenzyl ammonium chloride is added to the bentonite suspension under water bath heating conditions. After stirring and reacting, the mixture is cooled. The product is then centrifuged and the resulting precipitate is washed, centrifuged, dried, and crushed in sequence to obtain organic bentonite.

10. The method for preparing the dispersible oil suspension concentrate containing pyriproxyfen and dinotefuran according to any one of claims 1 to 9, characterized in that: The following steps are involved: (1) mixing a dispersion medium, an emulsifier, and a dispersant, shearing the mixture using a dispersion sand mill, adding pyriproxyfen, dinotefuran, a wetting agent, a tackifier, and a stabilizer, and continuing the shearing sand milling to obtain a semi-finished product; (2) The semi-finished product is transferred to a vertical sand mill for further sand grinding to obtain a dispersible oil suspension containing pyriproxyfen and dinotefuran.

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