An adjuvant combination for preparing a suspension concentrate, flufenacet water suspension concentrate and a preparation method thereof

Abstract

The application belongs to the field of pesticides, and particularly relates to an adjuvant combination for preparing a suspension agent, flufenacet water suspension agent and a preparation method thereof, wherein the adjuvant combination comprises, in parts by weight, 5-20 parts of a synergist, 5-15 parts of a wetting dispersant and 1-3 parts of a stabilizer; the synergist is one or a mixture of several of polyether, fatty alcohol ether and organosilicon; the wetting dispersant is one or a combination of any of high-molecular polyacrylate, polycarboxylate and polyester; and the stabilizer is EDTA sodium salt; the adjuvant combination is used for preparing the flufenacet water suspension agent, so that the storage stability and application performance of the preparation are improved, and the effects of reducing the cost of using the pesticide, increasing the effect with a reduced amount and environmental protection are achieved.

Description

Technical Field

[0001] This invention belongs to the field of pesticides, specifically relating to an adjuvant combination for preparing suspension concentrates, fluthiamethoxam aqueous suspension concentrate, and its preparation method. Background Technology

[0002] Fluthiamethoxam is a herbicide developed by Bayer AG of Germany. It belongs to the aryloxyacetamide class of compounds and primarily works by inhibiting cell division. It is mainly used in fields of corn, wheat, barley, soybeans, and other crops, and can broadly control annual grasses, sedges, and some small broadleaf weeds. Fluthiamethoxam is mainly used for soil treatment and can be applied pre-emergence or post-emergence. Physicochemical properties: The pure product is a white to brown solid; melting point 75-77℃; water solubility (mg / L, 25℃): 56 (pH 4, 7), 54 (pH 9). Other Chinese names: 4'-fluoro-N-isopropyl-2-[5-(trifluoroglycoside)-1,3,4-thiadiazon-2-imine]acetamide; 4'-fluoro-N-isopropyl-2-(5-trifluoromethyl-1,3,4-thiadiazol-2-yloxy)acetanilide. CAS No.: 142459-58-3, Molecular Formula: C14H13F4N3O2S, Structural Formula as follows:

[0003]

[0004] The primary application method for fluthiamethoxam formulations is soil treatment, specifically pre-emergence application. This involves spraying the pesticide onto the soil surface, making its spreading and suspension properties crucial for efficacy. The key indicators reflecting these properties are surface tension and suspension rate. Lower surface tension results in better spreading, while a higher suspension rate indicates more uniform pesticide adsorption in the soil. The most significant problem with fluthiamethoxam aqueous suspensions is their tendency to exhibit rapid particle elongation, crystallization, and paste-like formation during heat storage tests (national standards require a laboratory temperature of 54°C for 14 days to represent the stability of pesticide formulations stored at room temperature for 2 years) or after approximately one year of storage at room temperature. This affects the suspension rate and consequently, the efficacy. This phenomenon is a well-known problem within the industry, and a definitive solution remains unsolved.

[0005] Due to its unique structure, fluthiamethoxam technical powder contains multiple carbon-fluorine bonds and carbon-nitrogen single and double bonds, resulting in poor stability in water. In particular, the double bonds become extremely unstable at elevated temperatures, causing the technical powder to decompose, reducing the content of active ingredients, and consequently decreasing the efficacy.

[0006] In summary, there is an urgent need to find a suspension formulation system that can reduce the surface tension of the drug and effectively control particle size growth and inhibit the decomposition of the original drug during storage, thereby improving the storage stability and efficacy of the formulation. Summary of the Invention

[0007] To address the problems existing in the prior art, the present invention aims to provide an adjuvant combination for preparing suspensions, a fluthiamethoxam aqueous suspension, and a method for preparing the same. The adjuvant combination can improve the storage stability and application performance of the formulation, thereby achieving the effects of reducing medication costs, reducing dosage while increasing efficiency, and being environmentally friendly.

[0008] The technical solution of the present invention is as follows:

[0009] An adjuvant composition for preparing a suspension concentrate, comprising, by weight: 5-20 parts of synergist, 5-15 parts of wetting and dispersing agent, and 1-3 parts of stabilizer;

[0010] The synergist is one or a mixture of several of polyether, fatty alcohol ether, and organosilicon (mixed in any proportion);

[0011] The wetting and dispersing agent is one or any mixture of several of the following: high molecular weight acrylate, polyester, and polycarboxylate (mixed in any proportion).

[0012] Preferably, the wetting and dispersing agent may be one or any combination of Agrilan 700 (Nanjing Jierun Technology Co., Ltd.), DISPER D1000 (Suzhou Rongyida Chemical Co., Ltd.), GY-D800 (Beijing Guangyuan Yinong Chemical Co., Ltd.), 3241B (Jiangsu Qingyu Chemical Technology Co., Ltd.), DISPER 984 (Suzhou Rongyida Chemical Co., Ltd.), and GY-DS1610 (Beijing Guangyuan Yinong Chemical Co., Ltd.).

[0013] More preferably, the wetting and dispersing agent is a mixture of DISPER 984, DISPER D1000, and 3241B, wherein the mass ratio of DISPER 984, DISPER D1000, and 3241B is 3:2:2.

[0014] Preferably, the synergist is one of Silwet 408 (Nanjing Jierun Technology Co., Ltd.), JXW-102 (Jiangsu Jixin Biotechnology Co., Ltd.), and Greenwet 3718 (Beijing Greentech Technology Co., Ltd.).

[0015] Preferably, the stabilizer is sodium EDTA salt, specifically disodium EDTA (Jinan Xundali) or 3242E (Jiangsu Qingyu Chemical Technology Co., Ltd.).

[0016] Preferably, the optimal adjuvant composition comprises 10% JXW-102 (Jiangsu Jixin Biotechnology Co., Ltd.), 3% DISPER 984 (Suzhou Rongyida Chemical Co., Ltd.), 2% DISPER D1000 (Suzhou Rongyida Chemical Co., Ltd.), 2% 3241B (Jiangsu Qingyu Chemical Technology Co., Ltd.), and 1% 3242E (Jiangsu Qingyu Chemical Technology Co., Ltd.).

[0017] A fluthiamethoxam aqueous suspension, by weight percentage, comprises: 41% fluthiamethoxam, 18% adjuvants, 1.2% magnesium aluminum silicate, 4% glycerol, 0.2% Kathon, 0.3% liquid defoamer, and the balance being deionized water.

[0018] Preferably, the liquid defoamer can be an organosilicon or polysiloxane defoamer, specifically SAG1522 (Nanjing Jierun Technology Co., Ltd.) or GY-X60 (Beijing Guangyuan Yinong Chemical Co., Ltd.).

[0019] A method for preparing fluthiamethoxam aqueous suspension comprises the following steps: First, 20% deionized water is pumped into the feeding vessel (the amount of deionized water added is 20% of the mass of the suspension). Then, fluthiamethoxam, magnesium aluminum silicate, and the solid materials in the adjuvant combination are added. Next, the liquid materials of the adjuvant combination, glycerol, Kathon, and the remaining deionized water are pumped into the feeding vessel. Finally, liquid defoamer is slowly poured into the vessel opening. The mixture is sheared for 30-45 minutes and then sand-milled for 1.5-2 hours until the particle size D90 is ≤5.0 μm, thus preparing the fluthiamethoxam aqueous suspension.

[0020] Preferably, the temperature should be controlled below 35°C during the grinding process. Excessive temperature may cause changes in the properties of the active ingredient and adjuvants, ultimately leading to the formulation becoming viscous or even flocculating.

[0021] The main problem with fluthiamethoxam aqueous suspension concentrate is its tendency to exhibit rapid particle size increase, crystallization, and paste formation, which affects the suspension rate and thus the efficacy of the pesticide. Through extensive research and development, the inventors have discovered that by adding the adjuvant combination of this invention, the storage stability and application performance of the formulation can be improved, thereby achieving the effects of reducing application costs, increasing efficacy with reduced dosage, and environmental protection. The single agent can be used alone or mixed with other soil-applied pesticides, exhibiting good compatibility.

[0022] This invention utilizes a combination of special synergists, wetting and dispersing agents, and stabilizers to prepare fluthiamethoxam suspensions. This results in fluthiamethoxam suspensions with low surface tension and high suspension rates, solving the problems of active ingredient decomposition and rapid particle size increase leading to decreased suspension rates during storage. This improves the storage stability and efficacy of the formulation. The formulation of this invention is an aqueous suspension, using water as the continuous phase to replace large amounts of organic solvents and other chemical oils. This not only improves the safety of production, storage, and transportation but also significantly reduces environmental pollution, resulting in significantly enhanced overall benefits. Adding the specific adjuvant composition developed in this invention to the fluthiamethoxam aqueous suspension, after heat storage testing, demonstrates excellent performance. The decomposition rate can be as low as 2.4%, the surface tension can be reduced by 200 times to 28.8 mN / m, and the suspension rate is as high as 96.2%. The small particle size also solves the problem that fluthiamethoxam aqueous suspensions easily develop rapid particle size increase, crystallization, and paste formation after heat storage or one year of storage, affecting the suspension rate and thus the efficacy of the drug.

[0023] This invention provides an adjuvant combination that solves the stability problem of fluthiamethoxam water suspension, addressing the issue of decreased suspension rate due to steeply elongated particle size during fluthiamethoxam suspension storage; it improves the control effect of fluthiamethoxam suspension by reducing the surface tension of the agent; and it solves the problem of decomposition of the active ingredients in fluthiamethoxam suspension. This invention does not contain organic solvents or chemical oil components, effectively reducing environmental pollution and contributing to the protection of the agricultural ecological environment. Detailed Implementation

[0024] The technical solutions in the embodiments of the present invention will be clearly and completely described below. 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.

[0025] Except for the manufacturers specifically specified in the above invention, the materials used in the following embodiments are not special and can all be obtained through commercial means.

[0026] Example 1: 41% Fluthiamethoxam Aqueous Suspension

[0027] By weight percentage: fluthiamethoxam technical grade 41%, adjuvant combination 18% (of which Greenwet 3718 is 10%, DISPER 984 is 3%, DISPER D1000 is 2%, 3241B is 2%, 3242E is 1%), magnesium aluminum silicate 1.2%, glycerol 4%, Kathon 0.2%, SAG1522 0.3%, deionized water to make up to 100%.

[0028] Example 2: 41% Fluthiamethoxam Aqueous Suspension

[0029] By weight percentage: fluthiamethoxam technical grade 41%, adjuvant combination 18% (of which JXW-102 is 10%, DISPER984 is 3%, DISPER D1000 is 2%, 3241B is 2%, 3242E is 1%), magnesium aluminum silicate 1.2%, glycerol 4%, Kathon 0.2%, SAG1522 0.3%, deionized water to make up to 100%.

[0030] Example 3: 41% Fluthiamethoxam Aqueous Suspension

[0031] By weight percentage: fluthiamethoxam technical grade 41%, adjuvant combination 18% (of which JXW-102 is 10%, GY-DS1610 is 3%, DISPER D1000 is 2%, 3242E is 1%, 3241B is 2%), magnesium aluminum silicate 1.2%, glycerol 4%, Kathon 0.2%, SAG1522 is 0.3%, and deionized water is added to make up 100%.

[0032] Example 4: 41% Fluthiamethoxam Aqueous Suspension

[0033] By weight percentage: fluthiamethoxam technical grade 41%, adjuvant combination 18% (of which JXW-102 is 10%, DISPER984 is 3%, Agrilan 700 is 2%, 3242E is 1%, 3241B is 2%), magnesium aluminum silicate 1.2%, glycerol 4%, Kathon 0.2%, GY-X60 0.3%, deionized water to make up 100%.

[0034] Example 5: 41% Fluthiamethoxam Aqueous Suspension

[0035] By weight percentage: fluthiamethoxam technical grade 41%, adjuvant combination 18% (of which JXW-102 is 10%, DISPER984 is 3%, DISPER D1000 is 2%, disodium EDTA is 1%, 3241B is 2%), magnesium aluminum silicate 1.2%, glycerol 4%, Kathon 0.2%, GY-X60 is 0.3%, and deionized water is added to make up 100%.

[0036] Example 6: 41% Fluthiamethoxam Aqueous Suspension

[0037] By weight percentage: fluthiamethoxam technical grade 41%, adjuvant combination 18% (of which JXW-102 is 10%, DISPER984 is 3%, DISPER D1000 is 2%, 3242E is 1%, GY-D800 is 2%), magnesium aluminum silicate 1.2%, glycerol 4%, Kathon 0.2%, SAG1522 0.3%, deionized water to make up to 100%.

[0038] Comparative Example 1: 41% Fluthiamethoxam Aqueous Suspension

[0039] By weight percentage: fluthiamethoxam technical grade 41%, adjuvant combination 8% (DISPER 984 3%, DISPERD1000 2%, 3242E 1%, 3241B 2%), magnesium aluminum silicate 1.2%, glycerol 4%, Kathon 0.2%, SAG1522 0.3%, deionized water to make up to 100%.

[0040] Comparative Example 2: 41% Fluthiamethoxam Aqueous Suspension

[0041] By weight percentage: fluthiamethoxam technical grade 41%, adjuvant combination 8% (Weilai Huinan 2208 3%, SC864 2%, sodium benzoate 1%, Shanghai Wanjin WJF1000 2%), magnesium aluminum silicate 1.2%, glycerol 4%, Kathon 0.2%, SAG1522 0.3%, deionized water to make up to 100%.

[0042] The above formulas are all prepared according to the following methods, with specific steps as follows:

[0043] First, add 20% deionized water to the feeding vessel (20% of the mass of the added deionized water suspension), then add the solid materials from the fluthiamethoxam, magnesium aluminum silicate, and adjuvant combination. Next, add the liquid materials from the adjuvant combination, glycerol, Kathon, and the remaining deionized water to the feeding vessel. Finally, slowly pour the liquid defoamer into the vessel. Then, mill the mixture in three horizontal sand mills for 90 minutes. The particle size D90 ≤ 5.0 μm is then obtained, thus preparing the fluthiamethoxam aqueous suspension sample.

[0044] Experimental Example 1

[0045] 100 grams of the sample prepared according to the above examples and comparative examples were weighed and 40 ml of 1.0-1.2 mm 95 zirconium beads were added to the grinding jar. Under the condition of circulating water cooling, the material temperature was controlled below 35°C and ground for 90 min with a small vertical sand mill at a speed of 1800 r / min. All examples were ground under these conditions to compare the grinding effect of the adjuvant system on the active pharmaceutical ingredient particles.

[0046] Perform data testing using the following methods:

[0047] 1. The mass fraction of the active ingredient was determined by high performance liquid chromatography.

[0048] 2. The suspension rate test method shall be performed in accordance with CIPAC MT 184;

[0049] 3. Persistent foaming performance shall be tested according to CIPAC MT 47.2;

[0050] 4. The 200-fold surface tension test was conducted according to GB6541 (circular ring method), using a ZL-2 self-determining tensiometer (Shandong Kesen).

[0051] 5. Particle size was determined using a BT-9300ST laser particle size analyzer (Dandong Better).

[0052] 6. Thermal storage stability shall be tested in accordance with section 2.3 of GB / T 19136-2003. Data testing after thermal storage shall be conducted in accordance with the above methods.

[0053] Table 1. Results of sample quality index testing:

[0054]

[0055]

[0056] Note: Water surface tension (20℃) 70mN / m.

[0057] Table 2. Quality index test results of samples after heat storage (54℃, 14 days, ampoule sealing):

[0058]

[0059] Tables 1 and 2 above mainly compare the performance differences of samples under normal conditions and after heat storage under different adjuvant combinations. A lower decomposition rate indicates less degradation of the active ingredient, higher heat storage content, and better efficacy under long-term storage conditions. Higher suspension rate, lower surface tension, and smaller particle size are more conducive to efficacy. Persistent foaming affects the application process; high foaming is detrimental to spraying. In the above data, the examples used different combinations of different synergists and adjuvants in the adjuvant combination. Comparative Example 1 used other adjuvants in the adjuvant composition of this invention besides the synergist. The stability of the sample in Comparative Example 1 was not significantly different from that of the examples, but the lack of synergist resulted in higher surface tension and poor spreading performance. The suspension in Comparative Example 2 used conventional adjuvants and did not use any adjuvants in the adjuvant composition of this invention. Under the same sand milling conditions, it had a larger particle size, higher surface tension, and the worst heat storage stability. Based on the above data comparison, the test data of the sample in Example 2 are all better than those of other examples. It has the lowest decomposition rate, the highest suspension rate, the lowest surface tension of 200 times, the smallest grinding particle size under the same conditions, and all performance after heat storage is better than that of other examples.

[0060] Experiment Example 2: Field Trial.

[0061] The experiment was conducted in Dawang Village, Dianzi Town, Boxing County, Shandong Province, with pre-emergence spraying applied after wheat sowing. During the experiment, all treatments maintained consistent environmental conditions: sunny weather, ambient temperature maintained between 18℃ and 32℃, and soil moisture above 90%. All experimental plots were the same size, with a total of 5 treatments including a control and a water control. Each treatment had two replicates, with intervals between treatments. The dosage was 75 grams of pesticide diluted in 15 liters of water, sprayed evenly and uniformly. Each treatment area was 10 square meters. Observations were conducted at 20 and 30 days after application. The control treatment involved spraying directly with water without any pesticide.

[0062] Pre-emergence herbicide control efficacy (%) = (number of weeds in the treated area / number of weeds in the control area) × 100;

[0063] The blank treatment area uses a water control.

[0064] Table 3. Results of the prevention effect of different embodiments and blank treatment:

[0065]

[0066] As can be clearly seen from Table 3, the 20-day and 30-day control efficacy against *Hedysarum mongolicum*, *Stellaria media*, and *Bryum arvense* treated according to the embodiments of the present invention is much higher than that of the control in Comparative Example 1. In particular, the control efficacy against weeds treated according to Example 2 can reach more than 85%, and the 30-day control efficacy can reach as high as 91.1%, achieving remarkable results.

[0067] The adjuvant combination of this invention solves the problem of decreased suspension rate caused by the rapid increase in particle size during the storage of fluthiamethoxam suspension; it improves the control effect of fluthiamethoxam suspension by reducing the surface tension of the agent; it solves the problem of decomposition of active ingredients in fluthiamethoxam suspension by screening a reasonable adjuvant combination; and it uses water as the continuous phase to replace a large amount of organic solvents and other chemical oils, and does not contain organic solvents or chemical oil components, effectively reducing environmental pollution and helping to protect the agricultural ecological environment.

Claims

1. A fluthiamethoxam aqueous suspension concentrate, characterized in that, By weight percentage, it includes: fluthiamethoxam 41%, adjuvant combination 18%, magnesium aluminum silicate 1.2%, glycerol 4%, Kathon 0.2%, liquid defoamer 0.3%, and deionized water balance; The adjuvant combination, by weight, comprises: 5-20 parts of synergist, 5-15 parts of wetting and dispersing agent, and 1-3 parts of stabilizer; The synergist is one or a mixture of several of polyether, fatty alcohol ether, and organosilicon; The wetting and dispersing agent is one or a mixture of several of the following: high molecular weight acrylate, polycarboxylate, and polyester. The stabilizer is disodium EDTA or 3242E; The synergist is one of JXW-102 and Greenwet 3718; The wetting and dispersing agent is a mixture of DISPER 984, DISPER D1000, and 3241B, wherein the mass ratio of DISPER 984, DISPER D1000, and 3241B is 3:2:

2.

2. The method for preparing a fluthiamethoxam aqueous suspension according to claim 1, characterized in that, The specific steps of its preparation method are as follows: First, 20% deionized water is pumped into the feeding vessel, then the solid materials of fluthiamethoxam, magnesium aluminum silicate and adjuvant combination are added, then the liquid materials of adjuvant combination, glycerol, Kathon and the remaining deionized water are pumped into the feeding vessel, and finally the liquid defoamer is slowly poured into the vessel opening, sheared for 30-45 minutes, and then sand-milled once to prepare fluthiamethoxam aqueous suspension.

3. The method for preparing a fluthiamethoxam aqueous suspension according to claim 1, characterized in that, Grind until the particle size D90 ≤ 5.0 μm.

4. The method for preparing a fluthiamethoxam aqueous suspension according to claim 3, characterized in that, During the sand milling process, the temperature needs to be controlled below 35℃.

5. The method for preparing a fluthiamethoxam aqueous suspension according to claim 1, characterized in that, The liquid defoamer may be an organosilicon or polysiloxane defoamer.

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