A pyrethroid pesticide microemulsion aid and a preparation method thereof

Abstract

The present application relates to A01N25 / 30, and more particularly to a kind of pyrethrum pesticide microemulsion formulation auxiliary and its preparation method. According to weight parts, preparation raw material at least includes: pesticide emulsifier 10-30 parts, anhydrous calcium salt 45-55 parts, polyether 15-25 parts, polyhydric alcohol compound 5-15 parts. The pyrethrum pesticide microemulsion formulation auxiliary and its preparation method provided by the present application can effectively improve the penetration ability of pyrethrum pesticide, and assist to improve the insecticidal effect.

Description

Technical Field

[0001] This invention relates to A01N25 / 30, specifically to an adjuvant for pyrethroid pesticide microemulsion formulations and its preparation method. Background Technology

[0002] Pyrethroid pesticides are broad-spectrum insecticides characterized by rapid action, high efficiency, low toxicity, low residue, and safety for crops. With advancements in social production, microemulsions are playing an important role in pesticide development as a novel pesticide formulation, aiming to reduce environmental pressures.

[0003] Patent CN201210007541.8 describes a 4.5% high-efficiency cypermethrin microemulsion. This microemulsion, obtained through the interaction of emulsifiers, cosolvents, co-emulsifiers, antifreeze agents, stabilizers, and other additives with high-efficiency cypermethrin, reduces environmental pollution and protects the ecological environment.

[0004] The patented CN95115690.X series of insecticidal microemulsion compositions, prepared by the interaction of cosolvents, emulsifiers, water, and pyrethroids and methomyl, have the advantages of strong penetration and low pollution.

[0005] However, existing technologies require the combined action of multiple additives, resulting in high production costs and complex preparation processes, which cannot fully meet the requirements for emulsification stability. Summary of the Invention

[0006] To solve the above-mentioned technical problems, the first aspect of the present invention provides an adjuvant for pyrethroid pesticide microemulsion formulations, wherein the raw materials for preparation include at least the following by weight: 10-30 parts of pesticide emulsifier, 45-55 parts of anhydrous calcium salt, 15-25 parts of polyether, and 5-15 parts of polyol compound.

[0007] Preferably, the pesticide emulsifier has a pH value of 2-5 under 1% aqueous solution conditions.

[0008] Preferably, the pesticide emulsifier includes at least one of alkylphenol polyoxyethylene ether emulsifiers, fatty alcohol polyoxyethylene ether emulsifiers, polyol fatty acid ester emulsifiers, sulfate emulsifiers, and phosphate ester emulsifiers.

[0009] More preferably, the pesticide emulsifier includes phosphate ester emulsifiers.

[0010] More preferably, the pesticide emulsifier comprises tristyrene-phenylphenol resin polyoxyethylene ether phosphate.

[0011] Preferably, the pesticide emulsifier contains ≥85wt% of the active ingredient.

[0012] Preferably, the anhydrous calcium salt has a solid content of 50 wt% and / or 70 wt%.

[0013] More preferably, the anhydrous calcium salt has a solid content of 70 wt%.

[0014] More preferably, the anhydrous calcium salt has a solid content of 70 wt% and a moisture content of ≤0.5 wt%.

[0015] Preferably, the anhydrous calcium salt has a pH value of 5-7.

[0016] Preferably, the solvent in the anhydrous calcium salt includes at least one of alkanes, aromatics, and n-butanol.

[0017] More preferably, the solvent in the anhydrous calcium salt includes n-butanol.

[0018] Preferably, the anhydrous calcium salt comprises linear dodecylbenzenesulfonate calcium and / or branched dodecylbenzenesulfonate calcium.

[0019] Preferably, the polyether comprises at least one of benzylphenol polyoxyethylene ether, styrene-phenol polyoxyethylene ether, phenethylphenol polyoxyethylene ether polyoxypropylene ether, and fatty amine polyoxyethylene ether.

[0020] More preferably, the polyether comprises styrene-based phenolic polyoxyethylene ether.

[0021] More preferably, the polyether comprises tristyrene-phenylphenol polyoxyethylene ether.

[0022] Preferably, the polyether has a pH of 5-7 under 1% aqueous solution conditions.

[0023] Preferably, the polyether has an HLB value of 13-17.

[0024] Preferably, the polyether has a cloud point of 60-85°C under 1% aqueous solution conditions.

[0025] Preferably, the polyether comprises a first polyether and a second polyether. The mass ratio of the first polyether to the second polyether is (3-5):(5-7).

[0026] Preferably, the first polyether has an HLB value of 13-14 and a cloud point of 60-65°C under 1% aqueous solution conditions.

[0027] Preferably, the second polyether has an HLB value of 15-16 and a cloud point of 80-85°C under 1% aqueous solution conditions.

[0028] Preferably, the polyol compound includes at least one of ethylene glycol, propylene glycol, glycerol, butanediol, and pentanediol.

[0029] More preferably, the polyol compound includes ethylene glycol.

[0030] Preferably, the pesticide emulsifier, anhydrous calcium salt, and polyether are in a mass ratio of 20:50:20.

[0031] More preferably, the raw materials for preparation include at least: 20 parts of pesticide emulsifier, 50 parts of anhydrous calcium salt, 20 parts of polyether, and 10 parts of polyol compound.

[0032] The second aspect of the present invention provides a method for preparing a special adjuvant for water suspension preparations, comprising at least the following steps: pumping anhydrous calcium salt into a stirred tank, then adding polyether and pesticide emulsifier, and finally adding a polyol compound, stirring and heating to a constant temperature, maintaining the temperature, and then discharging the material through a filter to obtain the final product.

[0033] Preferably, the temperature at which the temperature is raised to a constant temperature is 40-45°C.

[0034] Preferably, the heat preservation time is 20-40 minutes.

[0035] Beneficial effects:

[0036] 1) This invention provides an adjuvant for pyrethroid pesticide microemulsion formulations and its preparation method. The pyrethroid pesticide microemulsion formulation prepared by limiting the content and type of each substance in the system has a moderate pH, good emulsification stability, and can effectively improve the penetration ability of pyrethroid pesticides and help improve the insecticidal effect.

[0037] 2) Pyrethroid pesticide microemulsion formulations have advantages such as smaller active ingredient particle size, higher biological activity, and stronger penetration ability. However, because they are microemulsion liquids, they are prone to becoming unstable dispersion systems. This invention limits the mass ratio of pesticide emulsifier, anhydrous calcium salt, and polyether to 20:50:20, achieving synergistic effects and enhancing efficacy. This controls the cloud point of the system, resulting in higher emulsification stability and further increases the penetration and adhesion ability of pyrethroid pesticides on plants, leading to better insecticidal effects. It also prevents aggregation caused by insufficient pesticide emulsifier and anhydrous calcium salt content.

[0038] 3) Microemulsion systems not only have limited inherent stability but are also easily affected by the external environment, leading to precipitation, separation, and stratification. This invention further limits the types of polyethers used. By using different tristyrylphenol polyoxyethylene ethers for compounding, the content of polyoxyethylene segments is controlled. A first polyether with an HLB value of 13-14 and a cloud point of 60-65℃ in 1% aqueous solution and a second polyether with an HLB value of 15-16 and a cloud point of 80-85℃ in 1% aqueous solution are blended with anhydrous calcium salts with good lipophilicity to improve solubilization and increase wetting and penetration capabilities. In particular, when the mass ratio is 4:6, it has a wider applicability to water temperature and water quality.

[0039] 4) This invention further alters the interaction between particles by using anhydrous calcium salts, including linear dodecylbenzenesulfonate and branched dodecylbenzenesulfonate, with a solid content of 70%, a moisture content of ≤0.5%, and n-butanol as the solvent. This facilitates the formation of a microemulsion system and, together with ethylene glycol in the system, enhances the low-temperature stability of adjuvants used in pyrethroid pesticide microemulsion formulations.

[0040] 5) This invention also uses 90% effective content of tristyrene-phenol resin polyoxyethylene ether phosphate and 70% solid content of anhydrous calcium salt, tristyrene-phenol polyoxyethylene ether, and ethylene glycol to reduce the tendency of particles to automatically aggregate in the system, change the instability of kinetics and thermodynamics, lower the freezing point, improve the fluidity, and improve its emulsification stability, so that the prepared pyrethroid pesticide microemulsion formulation has the effect of small particle size of active ingredient and stronger insecticidal ability. Detailed Implementation

[0041] Example

[0042] Example 1

[0043] An adjuvant for pyrethroid pesticide microemulsion formulations, comprising, by weight, 20 parts pesticide emulsifier, 50 parts anhydrous calcium salt, 20 parts polyether, and 10 parts polyol compound.

[0044] The pesticide emulsifier comprises tristyrene-phenol resin polyoxyethylene ether phosphate. The active ingredient content in the pesticide emulsifier is 90 wt%. It was purchased from Nantong Chenrun Chemical Co., Ltd., model: TSPEPO.

[0045] The anhydrous calcium salt has a solid content of 70 wt% and a moisture content of ≤0.5 wt%. The pH value of the anhydrous calcium salt is 5-7. The solvent in the anhydrous calcium salt includes n-butanol. The anhydrous calcium salt includes linear dodecylbenzenesulfonate calcium and branched dodecylbenzenesulfonate calcium. Purchased from Nantong Qianhe Chemical Co., Ltd., model 507.

[0046] The polyether comprises a first polyether and a second polyether. The mass ratio of the first polyether to the second polyether is 4:6. All polyethers are tristyrene-phenol polyoxyethylene ethers, wherein the first polyether has an HLB value of 13-14 and a cloud point of 60-65°C under 1% aqueous solution conditions. Model: 601. The second polyether has an HLB value of 15-16 and a cloud point of 80-85°C under 1% aqueous solution conditions. Model: 602. All polyethers are purchased from Xingtai Xinlanxing Technology Co., Ltd.

[0047] The polyol compounds include ethylene glycol, purchased from Weifang Hengruitong New Materials Co., Ltd.

[0048] A method for preparing a special adjuvant for water suspension concentrates includes the following steps: pumping anhydrous calcium salt into a stirred tank, then adding polyether and pesticide emulsifier, and finally adding a polyol compound while stirring and heating to a constant temperature. After holding at this temperature, the mixture is filtered and discharged to obtain the final product. The temperature for heating to the constant temperature is 42°C, and the holding time is 30 minutes.

[0049] Example 2

[0050] An adjuvant for pyrethroid pesticide microemulsion formulations, the specific implementation method is the same as in Example 1, except that the temperature at which the temperature is raised to a constant temperature is 45°C.

[0051] Example 3

[0052] An adjuvant for pyrethroid pesticide microemulsion formulations is described, with the specific implementation method being the same as in Example 1, except that the anhydrous calcium salt is replaced with pesticide 500#, the active ingredient content is ≥70wt%, the moisture content is <8wt%, and the methanol content is <30wt%. It was purchased from Xingtai Xinlanxing Technology Co., Ltd.

[0053] Comparative Example 1

[0054] An adjuvant for pyrethroid pesticide microemulsion formulations is disclosed, with the specific implementation method being the same as in Example 1, except that the polyether comprises a first polyether and a second polyether. The mass ratio of the first polyether to the second polyether is 4:8.

[0055] Comparative Example 2

[0056] An adjuvant for pyrethroid pesticide microemulsion formulations is described in the same manner as in Example 1, except that the raw materials for preparation include: 20 parts pesticide emulsifier, 50 parts anhydrous calcium salt, 12 parts polyether, and 10 parts polyol compound.

[0057] Performance testing

[0058] 1. pH value: Tested according to national standard GB / T6368;

[0059] 2. Emulsification stability: The test was carried out in accordance with the national standard GB / T3776.3: The technical material (cyfluthrin, purchased from Hubei Maoerwo Biopharmaceutical Co., Ltd.), the adjuvant and solvent (n-butanol) for the microemulsion preparation of pyrethroid pesticides were mixed in a mass ratio of 5:15:5, and appropriately heated and stirred evenly to form an emulsifiable concentrate. Then, in a 250 mL beaker, 99 mL of distilled water at 30 ± 1 °C and 1 mL of hard water mother liquor at 34200 ppm were added to prepare standard hard water (the hardness was 342 ppm in terms of calcium carbonate). The emulsifiable concentrate sample was sucked with a syringe and slowly added to the hard water under continuous stirring to form a 100 mL emulsion. After addition, continue to stir at a speed of 3 revolutions per second for 30 s, immediately transfer the emulsifiable concentrate to a clean 100 mL graduated cylinder, and place the graduated cylinder in a constant temperature water bath at 30 ± 1 °C. After standing for 1 h, take it out and observe the separation of the emulsion. If there is no floating oil, sinking oil or precipitation in the graduated cylinder, the stability is qualified.

[0060] Table 1 Performance test results

[0061] pH value Emulsion stability Example 1 7.2 qualified Example 2 6.8 qualified Example 3 8.0 qualified Comparative Example 1 6.0 Unqualified Comparative Example 2 5.2 Unqualified

Claims

1. An adjuvant for pyrethroid pesticide microemulsion formulations, characterized in that, The raw materials prepared by weight are: 20 parts pesticide emulsifier, 50 parts anhydrous calcium salt, 20 parts polyether, and 10 parts polyol compound. The pesticide emulsifier is tristyrene-phenol resin polyoxyethylene ether phosphate, and the active ingredient content in the pesticide emulsifier is 90 wt%. The anhydrous calcium salt is straight-chain calcium dodecylbenzenesulfonate and branched-chain calcium dodecylbenzenesulfonate. The anhydrous calcium salt has a solid content of 70 wt% and a moisture content of ≤0.5 wt%; the pH value of the anhydrous calcium salt is 5-7; and the solvent in the anhydrous calcium salt is n-butanol. The polyether is a first polyether and a second polyether, and the mass ratio of the first polyether and the second polyether is 4:6; both the first polyether and the second polyether are tristyrene-phenol polyoxyethylene ether. The first polyether has an HLB value of 13-14 and a cloud point of 60-65°C under 1% aqueous solution conditions; The second polyether has an HLB value of 15-16 and a cloud point of 80-85°C under 1% aqueous solution conditions; The polyol compound is ethylene glycol; The preparation method of the adjuvant for the pyrethroid pesticide microemulsion formulation includes the following steps: pumping anhydrous calcium salt into a stirred tank, then adding polyether and pesticide emulsifier, and finally adding polyol compound, stirring and heating to a constant temperature, holding at the temperature, and then discharging through a filter to obtain the final product; the temperature for heating to a constant temperature is 42°C, and the holding time is 30 minutes.

2. A method for preparing an adjuvant for a pyrethroid pesticide microemulsion formulation according to claim 1, characterized in that, Includes the following steps: Anhydrous calcium salt is pumped into a stirred tank, followed by the addition of polyether and pesticide emulsifier, and finally polyol compounds. The mixture is stirred and heated to a constant temperature. After holding at this temperature, the mixture is filtered and discharged to obtain the final product. The constant temperature is 42°C, and the holding time is 30 minutes.