S-methoprene missible oil protective agent for grain storage and preparation process of S-methoprene missible oil protective agent

Abstract

The invention belongs to the technical field of grain pest control, and discloses an S-methoprene missible oil protective agent for grain storage and a preparation process of the S-methoprene missible oil protective agent. 10-12% of a penetrant; 2-3% of a surfactant; 0.2% of an anti-ultraviolet agent; 1% of an antioxidant; and the balance solvent oil. S-methoprene is heated to 40-50 DEG C and stirred at a constant temperature until the S-methoprene is completely transparent; sulfonated sodium dioctyl succinate, lauryl alcohol polyoxyethylene ether, tetradecyl alcohol polyoxyethylene ether, titanium dioxide and ascorbic acid are sequentially added, and segmented stirring is conducted till the mixture is uniform. The characteristic that S-methoprene serves as an insect growth regulator is utilized, the population density of stored pests can be controlled in a long-acting mode, and S-methoprene is in a high-concentration formula, so that the solvent and packaging dosage is remarkably reduced, and the transportation and storage cost is reduced. Secondly, the missible oil preparation can form a slow release system and can be better attached to the surfaces of grains, the pesticide effect period is prolonged, and the pesticide application frequency is reduced.

Description

Technical Field

[0001] This invention relates to the field of grain pest control technology, and more specifically, to S-acetamiprid emulsifiable concentrate protectant for grain storage and its preparation process. Background Technology

[0002] Currently, grain storage protection mainly relies on chemical agents, especially the long-term use of highly toxic chemical pesticides such as aluminum phosphide fumigation. This results in high chemical residues in grains, a high degree of danger in use, and strong corrosiveness and harm to human health and equipment. Long-term use of chemical agents has led to a surge in pesticide resistance among stored-store pests, directly resulting in more frequent pesticide application. This cyclical application increases the difficulty of pesticide application and raises the cost of grain storage.

[0003] Biopesticides, due to their advantages such as strong targeting, no resistance development, and low residues, have become an important direction for replacing chemical pesticides. However, existing biopesticides (such as azadirachtin, osthol, and spinosad) are mostly in powder or suspension form, which have the following limitations: 1. Short efficacy cycle: Frequent application is required, increasing storage and management costs.

[0004] 2. Poor adhesion: The powder is prone to settling and difficult to distribute evenly, which affects the control effect.

[0005] 3. High transportation costs: Low-concentration formulations are bulky, increasing logistics costs.

[0006] Therefore, there is an urgent need to develop a high-concentration, long-lasting, stable, and easy-to-apply biological pesticide formulation to meet the demands of modern green grain storage.

[0007] S-methoprene is a juvenile hormone analog (JHA) that inhibits larval development into adults by mimicking the specific interference of natural juvenile hormones (JH) during insect molting, rather than relying on neurotoxicity. Its mechanism of action and advantages include: 1. Targeted interference with insect molting: It binds to insect juvenile hormone receptors (such as Met protein), downregulates the expression of the molting hormone receptor gene (EcR), upregulates the juvenile hormone response gene (Kr-h1), and blocks the transformation of larvae into adults; 2. Inhibition of reproduction and chitin synthesis: Reduces the number of eggs laid by adults and the hatching rate of eggs, inhibits the activity of chitin synthase, and hinders the hardening of the larval epidermis; 3. Enhanced synergistic effect: By inhibiting the insect's energy metabolism enzyme (ATPase) and detoxification enzyme (CYP450), the development of drug resistance is delayed.

[0008] Pilot applications in grain reserves have shown that treatment with 5 ppm S-tebufenozide can reduce the loss rate of corn and wheat by more than 90%, with a protection period of 2-3 years. It has a highly effective inhibitory effect on major stored-product pests such as rice weevils (LC50=1.2mg / kg) and grain borers (LC50=2.5mg / kg), and no chemical residues were detected.

[0009] Despite its significant advantages, S-acetamiprid is currently mainly registered as a wettable powder or granule both domestically and internationally, which has problems such as short efficacy period, uneven mixing, and high transportation costs. Summary of the Invention

[0010] The purpose of this invention is to address the shortcomings of existing technologies by proposing an S-acetamiprid emulsifiable concentrate protectant for grain storage and its preparation process, thereby solving the problems of short efficacy cycle, uneven mixing, and high transportation costs associated with traditional technologies.

[0011] To achieve the above objectives, the present invention adopts the following technical solution: S-tebufenozide emulsifiable concentrate for grain storage consists of the following components by weight percentage: S-acetamiprid 33.6%; penetrant 10-12%; surfactant 2-3%; UV stabilizer 0.2%; antioxidant 1%; balance solvent oil.

[0012] As a further aspect of the present invention: the S-acetamiprid is in oily form and is used after preheating to 40-50°C; the purity of the S-acetamiprid technical material is 95%.

[0013] As a further aspect of the present invention: the penetrant is sodium dioctyl sulfonate, and the UV stabilizer is titanium dioxide.

[0014] As a further aspect of the present invention: the surfactant is composed of 1.5-2% lauryl alcohol polyoxyethylene ether and 0.5-1% tetradecyl alcohol polyoxyethylene ether.

[0015] As a further aspect of the present invention, the antioxidant is ascorbic acid.

[0016] The preparation process of S-tebufenozide emulsifiable concentrate for grain storage includes the following steps: (1) Preheating of the active ingredient: Heat S-tebufenozide to 40-50℃ and stir at a constant temperature until it is completely transparent; (2) Mixing of additives: Add sodium dioctyl sulfonate, lauryl alcohol polyoxyethylene ether, tetradecyl alcohol polyoxyethylene ether, titanium dioxide and ascorbic acid in sequence, and stir in stages until homogeneous; (3) Homogenization treatment: The mixture is homogenized at 10,000-15,000 rpm for 10-15 minutes to make the particle size ≤2μm; (4) Solvent replenishment: Add the remaining solvent oil to adjust the final volume and mix evenly.

[0017] As a further aspect of the present invention: in step (1), the constant temperature is maintained at 50±5℃, the stirring speed is 300-500rpm, and the time is 30-60 minutes.

[0018] As a further aspect of the present invention, the sodium sulfonated dioctyl succinate salt in step (2) is added in batches.

[0019] Compared with the prior art, the advantages of this invention are: This invention utilizes the properties of S-acetamiprid as an insect growth regulator to effectively control the population density of stored pests. Furthermore, the high-concentration formulation of S-acetamiprid significantly reduces solvent and packaging usage, thereby lowering transportation and storage costs. Secondly, the emulsifiable concentrate form a slow-release system, allowing for better adhesion to grain surfaces, extending the efficacy period, and reducing application frequency. Optimizing the solvent and emulsification system enhances drug adhesion and grain pile permeability. The S-acetamiprid emulsifiable concentrate protectant developed in this invention meets the needs of my country's green grain storage technology upgrade, providing key technical support for building a "low-consumption, intelligent, and green" modern grain storage system, and exhibiting significant economic, ecological, and social benefits. Detailed Implementation

[0020] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] S-tebufenozide emulsifiable concentrate for grain storage consists of the following components by weight percentage: S-acetamiprid (95% TC, oil) 33.6%; sodium dioctyl sulfosuccinate 10-12%; lauryl alcohol polyoxyethylene ether 1.5-2%; tetradecyl alcohol polyoxyethylene ether 0.5-1%; titanium dioxide 0.2%; ascorbic acid 1%; solvent oil 52%.

[0022] In this formulation, sodium dioctyl sulfosuccinate is used as a penetrant, lauryl alcohol polyoxyethylene ether and tetradecyl alcohol polyoxyethylene ether are used as surfactants, titanium dioxide is used as a UV stabilizer, ascorbic acid is used as an antioxidant, and the solvent oil is an emulsifiable concentrate. S-acetamiprid needs to be preheated to 40-50℃ before use to reduce viscosity and prevent decomposition due to high temperatures.

[0023] In the above formulation, S-tebufenozide is used as an insect growth regulator to effectively control the population density of stored pests. Furthermore, the active ingredient of S-tebufenozide (95% TC, oil) is 33.6%, which is close to the upper limit of emulsifiable concentrate formulations (20-50%), significantly reducing solvent and packaging usage and reducing transportation and storage costs by more than 30%.

[0024] The 52% solvent oil can use low-cost petroleum-based solvents (such as 150# solvent oil), which have good compatibility with oily raw materials, avoid crystallization and precipitation (safer and more stable than polar solvents such as methanol / xylene), balance solubility and economy, and are suitable for industrial production.

[0025] Sodium dioctyl sulfosuccinate (10-12%) rapidly penetrates leaves and insects, increasing pesticide retention by over 50%. A non-ionic emulsifier blend (lauryl alcohol polyoxyethylene ether + tetradecyl alcohol polyoxyethylene ether) synergistically stabilizes the emulsion, spontaneously forming O / W droplets (≤2μm in diameter) upon dilution, thus extending the pesticide's duration of effect. Ascorbic acid (antioxidant) and titanium dioxide (physical stabilizer) replace traditionally harmful stabilizing ingredients.

[0026] In summary, this formulation contains no highly toxic solvents or restricted adjuvants, aligning with international pesticide registration trends. Emulsifiable concentrate formulations adhere better to grain surfaces, reducing volatilization and extending the formulation's efficacy period. It meets the requirements of "high efficiency, high efficacy, and low volatilization" plus "low pesticide activity, low pesticide residue, and low pesticide residue," namely: The "three high" characteristics are: high drug loading, high penetration, and high compatibility, which are suitable for resistance control needs.

[0027] The "double low" design means low environmental risk and low overall cost, meeting the requirements of sustainable agriculture.

[0028] Based on the above, the present invention also provides a preparation process for S-tebufenozide emulsifiable concentrate protectant for grain storage, comprising the following steps: (1) Preheating of the active ingredient: Heat S-tebufenozide (oil) to 40-50℃ to reduce viscosity and avoid decomposition due to high temperature. Maintain the temperature at 50±5℃, stir at 300-500rpm for 30-60 minutes until completely transparent.

[0029] (2) Mixing of additives: Add sodium dioctyl sulfonate in batches (to avoid excessive local concentration) and stir until homogeneous; then add lauryl alcohol polyoxyethylene ether and stir for 20 minutes. Add tetradecyl alcohol polyoxyethylene ether, titanium dioxide and ascorbic acid in sequence and continue to stir until homogeneous to obtain a mixture.

[0030] (3) Homogenization treatment: The mixture is treated with a homogenizer at 10,000-15,000 rpm for 10-15 minutes to make the particle size ≤2μm.

[0031] (4) Solvent replenishment: The remaining solvent oil is flushed into the pipeline and added to the reactor, mixed evenly, and the final volume is adjusted.

[0032] Based on the above, the production process of the present invention has the following advantages: (1) Simplified process flow, reducing investment threshold: The three core operations (dissolving → mixing → homogenizing) require only a conventional reactor and a homogenizer, without the need for complex equipment.

[0033] Suitable for small and medium-sized enterprises or those needing to quickly switch production, reducing fixed asset investment.

[0034] (2) Wide tolerance for process errors, flexible operation: It has a wide melting temperature range (40-60℃), eliminating the need for precise temperature control and reducing energy consumption and operational difficulty.

[0035] The addition order of additives is flexible, making it less likely to cause production failure due to material addition errors, and the finished product has high stability.

[0036] (3) Low energy consumption and high production efficiency: It does not require high temperature and high pressure or complex post-processing (such as spray drying), and its energy consumption is lower than that of water-based formulations (SC, EW, etc.).

[0037] The batch production cycle is short (2-3 hours / batch), the equipment utilization rate is high, and it is suitable for continuous production.

[0038] (4) Easy to control quality and excellent stability: Key indicators (such as emulsion stability and active ingredient content) can be rapidly detected using conventional methods (CIPAC method). It has a high pass rate in cold storage (4℃) and hot storage (54℃) tests, and its shelf life is usually ≥2 years.

[0039] Experimental Example: Evaluation of the Control Efficacy of 33.6% S-acetamiprid EC Formulation Against Pests in Stored Grains S-tebufenozide is not effective in a short period of time and only shows its effect after a growth cycle of stored pests. However, it can achieve good results in long-term protection. When used at a concentration of 5 ppm, it can provide protection for 2-3 years in the storage environment. Due to the strong target characteristics of S-tebufenozide, even very low concentrations can control the growth and development of pests, and it has good efficacy even at ppb level concentrations. During the storage period, S-tebufenozide degrades by 20% each year, and within the grain turnover cycle (2-3 years), it can reach the point where no pesticide is needed. Compared with the current frequency of aluminum phosphide fumigation 2-3 times per year, S-tebufenozide can truly achieve the standard of one application for 3 years.

[0040] The following is a simulated efficacy test conducted according to actual pesticide application standards in grain storage. The formulation used was a 33.6% emulsifiable concentrate, with three concentration gradients selected: 5 ppm, 10 ppm, and 15 ppm. The selected grain storage pests included red flour beetle, booklice, and meal borer. The control pesticide used was deltamethrin.

[0041] 1. Experimental Objective The mortality rate of 33.6% S-acetamiprid emulsifiable concentrate formulation against adult *Triplophysa rubrum*, booklice, and meal beetle and its inhibitory effect on F1 progeny populations were evaluated at different concentration gradients (5 ppm, 10 ppm, 15 ppm), and compared with the control agent deltamethrin (5 ppm).

[0042] 2. Materials and Methods Test agents: 33.6% S-acetamiprid EC (test agent) and deltamethrin EC (control agent).

[0043] The tested insect species were: adult red flour beetle (Tribolium castaneum), booklice (Liposcelis bostrychophila), and grain beetle (Rhyzopertha dominica).

[0044] Experimental Design: Three concentration gradients were set up: 5 ppm, 10 ppm, and 15 ppm, with each concentration repeated 3 times; the blank control (0 ppm) and the deltamethrin control (5 ppm) were run simultaneously.

[0045] The pesticide treatment employed a grain surface spraying method to simulate actual pesticide application conditions during storage.

[0046] Data Records: Adult mortality rate: The number of dead insects was counted 7 days after treatment, and the average mortality rate and corrected mortality rate (Abbott formula) were calculated.

[0047] F1 offspring suppression rate: The population suppression rate is calculated by continuously observing the molting of offspring.

[0048] 3. Experimental Results 3.1 Results of the trial on the control of stored grain pests using S-tebufen EC formulation

[0049] 3.2 Inhibition effect of F1 offspring At all concentrations, S-tebufenozide showed an inhibition rate of over 98% (for red flour beetles and grain beetles) or 100% (for booklice), comparable to that of deltamethrin (100%).

[0050] 4. Conclusion ① Control of adult insects: S-tebufenozide has the best lethal effect on red flour beetle (corrected mortality rate of 86.76% at 5 ppm), followed by booklice and meal beetle, and the effect increases significantly with increasing concentration.

[0051] ② Population control: A low dose of 5 ppm can achieve an inhibition rate of over 98% in the F1 generation, indicating that it has a highly effective blocking effect on stored grain pest populations, comparable to deltamethrin.

[0052] ③ Recommended dosage: Considering both cost and effectiveness, 5 ppm is the economically effective concentration, especially suitable for the control of red flour beetles and booklice; for meal beetles, the dosage can be appropriately increased to 10 ppm to enhance the killing effect on adults.

[0053] The above description is merely a preferred embodiment of the present invention; however, the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and its improved concept, should be covered within the scope of protection of the present invention.

Claims

1. S-acetamiprid emulsifiable concentrate preservative for grain storage, characterized in that: It consists of the following components by weight percentage: S-acetamiprid 33.6%; penetrant 10-12%; surfactant 2-3%; UV stabilizer 0.2%; antioxidant 1%; balance solvent oil.

2. The S-acetamiprid emulsifiable concentrate preservative for grain storage according to claim 1, characterized in that: The S-acetamiprid is in oil form and is used after preheating to 40-50℃; the purity of the S-acetamiprid technical material is 95%.

3. The S-tebufenozide emulsifiable concentrate preservative for grain storage according to claim 1, characterized in that: The penetrant is sodium dioctyl sulfonate, and the UV stabilizer is titanium dioxide.

4. The S-acetamiprid emulsifiable concentrate preservative for grain storage according to claim 1, characterized in that: The surfactant is composed of 1.5-2% lauryl alcohol polyoxyethylene ether and 0.5-1% tetradecyl alcohol polyoxyethylene ether.

5. The S-acetamiprid emulsifiable concentrate preservative for grain storage according to claim 1, characterized in that: The antioxidant is ascorbic acid.

6. The preparation process of S-tebufenozide emulsifiable concentrate preservative for grain storage according to any one of claims 1-5, characterized in that: Includes the following steps: (S1) Preheating of the technical grade: Heat S-tebufenozide to 40-50℃ and stir at a constant temperature until completely transparent; (S2) Additive mixing: Add sodium dioctyl sulfonate, lauryl alcohol polyoxyethylene ether, tetradecyl alcohol polyoxyethylene ether, titanium dioxide and ascorbic acid in sequence, and stir in stages until homogeneous; (S3) Homogenization treatment: The mixture is homogenized at 10,000-15,000 rpm for 10-15 minutes to make the particle size ≤2μm; (S4) Solvent replenishment: Add the remaining solvent oil to adjust the final volume and mix well.

7. The preparation process of the S-acetamiprid emulsifiable concentrate preservative for grain storage according to claim 6, characterized in that: In step (1), the constant temperature is maintained at 50±5℃, the stirring speed is 300-500rpm, and the time is 30-60 minutes.

8. The preparation process of the S-tebufenozide emulsifiable concentrate preservative for grain storage according to claim 6, characterized in that: The sodium sulfonated dioctyl succinate salt described in step (2) is added in batches.

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