Prothioconazole • epoxiconazole suspension and a preparation method thereof

Abstract

The present application relates to the technical field of pesticide production, in particular to a kind of propiconazol fluquinconazole suspending agent and preparation method thereof, by weight percentage, comprising: propiconazol 10-30%, fluquinconazole 5-15%, wetting dispersant 5-15%, magnesium aluminum silicate 0.1-1.5%, xanthan gum 0.01-0.5%, anti-freezing agent 3-8%, organic silicon 0.01-0.2%, preservative 0.01-0.2%, and deionized water makes up the rest, by optimizing product formula system, ensure stability while improving efficacy, and it is water-based preparation, dosage form is environmentally friendly, and it is friendly to environment, and toxicity is low toxicity, and the harm to human and other beneficial organisms is less.

Description

Technical Field

[0001] The invention relates to the technical field of pesticide production, in particular to a prothioconazole-epoxiconazole suspension concentrate and a preparation method thereof. Background Art

[0002] Prothioconazole is a triazolethione fungicide that acts as an inhibitor of sterol demethylation (ergosterol biosynthesis). It boasts a long-lasting effect, is safe for crops and the environment, and possesses a broad spectrum of activity, providing excellent control against nearly all fungal diseases in cereals. Epoxiconazole is a systemic triazole fungicide that inhibits ergosterol synthesis and cell wall formation, resulting in more effective antibacterial activity. It can also enhance chitinase activity in crops. Currently, the main focus of the compound formulation of prothioconazole and epoxiconazole is on improving drug efficacy and reducing resistance. For example, a Chinese patent application (publication number CN102258033A) provides a novel pesticide composition containing prothioconazole and triazoles. The novel pesticide composition mainly enhances the prevention effect and expands the fungicidal spectrum by compounding prothioconazole with epoxiconazole or hexaconazole. However, many problems still need to be overcome in order to make prothioconazole and epoxiconazole into a medicament that meets the quality requirements and can be used in practice, especially in developing a prothioconazole-epoxiconazole suspension concentrate product with excellent overall performance. A Chinese patent (publication number CN102599172A) discloses a fungicidal composition and its preparation, specifically disclosing that a 40% prothioconazole-epoxiconazole suspension concentrate is prepared using conventional sodium lauryl sulfonate, sodium lignin sulfonate, and xanthan gum. However, the heat storage stability of this product needs to be further improved. Summary of the Invention

[0003] On one hand, the present invention provides a prothioconazole-epoxiconazole suspension concentrate, which comprises, by weight percentage, 10-30% of prothioconazole technical, 5-15% of epoxiconazole technical, 5-15% of wetting and dispersing agent, 0.1-1.5% of magnesium aluminum silicate, 0.01-0.5% of xanthan gum, 3-8% of antifreeze agent, 0.01-0.2% of organosilicon, 0.01-0.2% of preservative, and the balance made up of deionized water.

[0004] As a preferred technical solution, the mass ratio of the prothioconazole technical and the epoxiconazole technical is (1-3):(1-3), preferably (2-3):1. By compounding prothioconazole and epoxiconazole in a mass ratio of (2-3):1 as the effective active ingredient, the present invention has a good synergistic effect, delays the development of drug resistance in diseases, and can reduce the dosage of the active ingredient. The reduced dosage also reduces the pressure of chemical pesticides on the environment and reduces damage to beneficial organisms.

[0005] As a preferred technical solution, the wetting and dispersing agent at least includes a sulfonate wetting and dispersing agent.

[0006] As a preferred technical solution, the wetting and dispersing agent further includes at least one of a modified carboxylate wetting and dispersing agent, an alkylnaphthalene formaldehyde condensate, and a phosphate wetting and dispersing agent.

[0007] Preferably, the wetting and dispersing agent includes at least a sulfonate wetting and dispersing agent and a modified carboxylate wetting and dispersing agent.

[0008] Preferably, the sulfonate wetting and dispersing agent comprises at least DS569, the modified carboxylate wetting and dispersing agent comprises at least DS809.

[0009] As a preferred technical solution, the wetting and dispersing agent also includes styrene-polyoxyethylene ether copolymer.

[0010] Preferably, the styrene-polyoxyethylene ether copolymer comprises at least DS8637.

[0011] Preferably, the mass ratio of the sulfonate wetting and dispersing agent, the modified carboxylate wetting and dispersing agent, and the styrene-polyoxyethylene ether copolymer is (2-8): (0.5-3): (2-6), preferably (4-6): (1-2): (3-5), and most preferably 5:1.5:4.

[0012] Pesticide suspension concentrates are unstable dispersion systems, particularly those that suffer from problems such as creaming during hot storage, particle size growth, reduced suspension efficiency, and water precipitation, resulting in a short product shelf life. During their research, the present invention discovered that by introducing a sulfonate wetting and dispersing agent and a modified carboxylate wetting and dispersing agent into a prothioconazole / epoxiconazole composite suspension concentrate system, a suspension concentrate product with a particle size d90 ≤ 3.5 μm can be prepared, compared to a single sulfonate wetting and dispersing agent, a modified carboxylate wetting and dispersing agent, an alkylnaphthalene formaldehyde condensate, or a phosphate wetting and dispersing agent. This product exhibits better hot storage stability, avoids creaming, bottoming, and reduced suspension efficiency during hot storage, and thus extends the product's shelf life. Furthermore, to further enhance the efficacy of the product, the present invention initially introduced synergists including silicone, polyvinyl alcohol, and polyacrylic acid into the system. However, the silicone synergist was not compatible with the other raw materials in the system, resulting in severe water precipitation in the suspension concentrate; the polyvinyl alcohol synergist increased the viscosity of the system, deteriorated the fluidity of the liquid, and affected dispersion; and the introduction of the polyacrylic acid synergist caused the product to flocculate after two weeks of hot storage. During the research process, the present invention unexpectedly discovered that by introducing a styrene-polyoxyethylene ether copolymer, controlling the mass ratio of a sulfonate wetting dispersant, a modified carboxylate wetting dispersant, and a styrene-polyoxyethylene ether copolymer to (2-8): (0.5-3): (2-6), and optimizing the process, the particle size was further sand-milled to d90 <1 μm, thereby achieving the preparation of a nano-scale prothioconazole-epoxiconazole composite suspension concentrate product, which improved the efficacy by about 10% and also solved the problem of the versatility of the prothioconazole technical.

[0013] As a preferred technical solution, the antifreeze agent is selected from at least one of ethylene glycol, propylene glycol, glycerol, and sodium chloride, preferably ethylene glycol.

[0014] Furthermore, by introducing ethylene glycol as an antifreeze agent, the problem of the product becoming solidified and paste-like due to increased viscosity during the sanding process is avoided, thereby reducing the cost of raw materials.

[0015] As a preferred technical solution, the mass ratio of the magnesium aluminum silicate to the xanthan gum is (2-10):1, preferably (5-8):1, and most preferably 6:1.

[0016] Preferably, the viscosity of the magnesium aluminum silicate at 25° C. (NDJ-5S viscometer, 3# rotor, 60 rpm) is 500-2000 mPa·s, preferably 800-1500 mPa·s.

[0017] Preferably, the magnesium aluminum silicate is selected from at least one of Weidino WF01, Weidino WF04, and Zhejiang Fenghong scgel-01, preferably Zhejiang Fenghong scgel-01.

[0018] Further, the present application introduces magnesium aluminum silicate and xanthan gum as thickening agents at the same time, especially controls the two-stage addition of xanthan gum, avoids the decrease of thickening performance caused by multiple grinding during sand milling, ensures the pouring property of the suspension agent product while effectively controlling the water separation effect, and reduces the continuous production caused by the sedimentation of materials due to gravity before passing through the sand mill, thereby ensuring the production continuity.

[0019] As a preferred technical solution, the organic silicon at least includes polydimethylsiloxane, model SAG1572 (MAYTACH).

[0020] The present application introduces polydimethylsiloxane and controls the two-stage addition of polydimethylsiloxane, reduces the generation of bubbles during shearing and stirring, defoams the sand-milled material faster, ensures the defoaming effect while improving the production efficiency.

[0021] As a preferred technical solution, the preservative includes 1,2-benzisothiazolin-3-one (BIT 20).

[0022] As a preferred technical solution, the deionized water is deionized water.

[0023] Another aspect of the present application provides a preparation method of propiconazole-flutriafol suspension, at least including the following steps: adding 20-40wt% of the total amount of deionized water, wetting dispersant and organic silicon into a container to obtain a dispersion A by shearing and dispersing; adding propiconazole technical material and flutriafol technical material into the dispersion A to obtain a dispersion B by stirring and dispersing; adding 20-40wt% of the total amount of xanthan gum and 20-40wt% of the total amount of antifreeze into the dispersion B to obtain a dispersion C by shearing and dispersing, adding 20-40wt% of the total amount of organic silicon to the dispersion C to obtain a dispersion by stirring and dispersing, and then sand milling; controlling the particle size D90 to be less than 3.5 microns during sand milling, and then sending the sample for wet screening after sand milling; adding the remaining amount of organic silicon, preservative and the mixture of the remaining amount of xanthan gum and the remaining amount of antifreeze into the dispersion after the wet screening is qualified, and then obtaining the propiconazole-flutriafol suspension by shearing and dispersing.

[0024] Preferably, the particle size D90 is controlled to be less than 1 micron during sand milling.

[0025] Beneficial effects

[0026] 1. The present application has good synergistic effect by compounding propiconazole and flutriafol as effective active ingredients at a mass ratio of (2-3):1, delays the drug resistance of diseases, and can reduce the use amount of effective ingredients. The reduction of use amount also reduces the pressure of chemical pesticides on the environment and the damage to beneficial organisms.

[0027] 2. The present invention introduces sulfonate wetting and dispersing agents and modified carboxylate wetting and dispersing agents into the prothioconazole-fluoxetone compound suspension concentrate system. Compared with single sulfonate wetting and dispersing agents, modified carboxylate wetting and dispersing agents, alkylnaphthalene formaldehyde condensate, and phosphate wetting and dispersing agents, a suspension concentrate product with a particle size d90 ≤ 3.5 μm can be prepared. The product has good heat storage stability, and will not cause problems such as creaming, bottoming, and reduced suspension rate during heat storage, thereby extending the shelf life of the product.

[0028] 3. By introducing a styrene-polyoxyethylene ether copolymer, controlling the mass ratio of a sulfonate wetting and dispersing agent, a modified carboxylate wetting and dispersing agent, and a styrene-polyoxyethylene ether copolymer to (2-8):(0.5-3):(2-6), and optimizing the process, the particle size is further sand-milled to d90 <1 μm to achieve the preparation of a nano-scale prothioconazole / epoxiconazole composite suspension concentrate product, which improves the efficacy by approximately 10% and solves the problem of the versatility of the prothioconazole technical.

[0029] 4. The present invention simultaneously introduces magnesium aluminum silicate and xanthan gum as thickeners, and especially controls the xanthan gum to be added in two stages, thereby avoiding the degradation of the thickening performance of the xanthan gum due to repeated grinding during the sand milling process, ensuring the pourability of the suspension product while effectively controlling the water separation effect, and reducing the sedimentation of the material due to gravity before passing through the sand mill, which leads to the inability to produce continuously, thereby ensuring production continuity.

[0030] 5. The suspension concentrate product provided by the present invention can be better absorbed and penetrated by crops, thereby improving efficacy. It also has a mature processing technology and is a water-based preparation. The dosage form is environmentally friendly and has low toxicity, and poses little harm to humans and other beneficial organisms. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 The results of water extraction after hot storage of the suspension concentrate products provided in Example 1 and Examples 5, 6, and 7 are shown in the figure. From right to left, they correspond to Example 1, Example 5, Example 6, and Example 7 respectively. DETAILED DESCRIPTION

[0032] Examples 1-9

[0033] On the one hand, Examples 1-9 of the present invention provide a prothioconazole-epoxiconazole suspension concentrate, and the formula thereof is shown in Table 1, calculated by weight percentage.

[0034] Table 1

[0035]

[0036]

[0037] In Table 1, prothioconazole technical 1 was from Qingdao Hailier Pharmaceutical Group Co., Ltd.; prothioconazole technical 2 was from Liaoning Zhonghui Biotechnology Co., Ltd.; and epoxiconazole technical was from Jiangsu Changqing Agrochemical Co., Ltd. DS569, DS809, DS8637 is from Guangzhou Fangzhong Chemical; SP-sc3219 is from Qingyu Additives; fs-3000 is from Takemoto, Japan; xanthan gum is from Jiangsu Qingyu; scgel-01 is from Zhejiang Fenghong, WF01 is from Weidino; attapulgite is from Tianke Minerals; SAG 1572 is from Maitu Chemical.

[0038] On the other hand, Examples 1-9 of the present invention provide a method for preparing a prothioconazole-epoxiconazole suspension concentrate, which specifically comprises the following steps: adding deionized water, a wetting dispersant, and 30 wt% of the total amount of silicones into a container and shearing and dispersing to obtain a dispersion A; adding prothioconazole technical and epoxiconazole technical to the dispersion A and stirring and dispersing to obtain a dispersion B; adding a mixture of 30 wt% of the total amount of xanthan gum and 30 wt% of the total amount of antifreeze and magnesium aluminum silicate into the dispersion B and shearing and dispersing to obtain a dispersion C; adding 30 wt% of the total amount of silicones and stirring and dispersing, and then sand milling; controlling the particle size to ≤3.5 μm during the sand milling, sending a sample for wet screening after the sand milling is completed, adding the remaining silicones, preservatives, and a mixture of the remaining xanthan gum and the remaining antifreeze after passing the wet screening, and shearing and dispersing to obtain the prothioconazole-epoxiconazole suspension concentrate.

[0039] Performance Testing

[0040] 1. The suspension concentrate products provided in Examples 1 and 8 were tested for the various physical and chemical properties listed in Table 2. The test basis and test results are shown in Table 2.

[0041] Table 2

[0042]

[0043]

[0044] 2. The particle size and suspension rate of the suspension concentrate products provided in Examples 2-4 after heat storage were tested. The test results are shown in Table 3.

[0045] Table 3

[0046]

[0047] 3. The suspension concentrate products provided in Example 1 and Examples 5, 6, 7, and 9 were tested for water separation before and after heat storage and pouring performance before and after washing. The test results are shown in Table 4 and Figure 1 .

[0048] Table 4

[0049]

[0050] 4. The results of the toxicity test of the mixture of prothioconazole and fluconazole against wheat fusarium sphaeroides are shown in Table 5.

[0051] Table 5

[0052]

[0053] 5. The suspension concentrate products provided in Examples 1 and 2 were subjected to field efficacy tests and compared with commercially available 125 g / L epoxiconazole suspension concentrate products and 30% prothioconazole dispersible oil suspension concentrate products. The results are shown in Table 6.

[0054] Table 6

[0055]

[0056]

Claims

1. A prothioconazole-epoxiconazole suspension concentrate, characterized in that: The invention comprises, by weight percentage, 10-30% of prothioconazole technical, 5-15% of fluopicolide technical, 5-15% of wetting and dispersing agent, 0.1-1.5% of magnesium aluminum silicate, 0.01-0.5% of xanthan gum, 3-8% of antifreeze agent, 0.01-0.2% of organosilicon, 0.01-0.2% of preservative, and the balance made up of deionized water; the wetting and dispersing agent comprises at least a sulfonate wetting and dispersing agent, further comprises a modified carboxylate wetting and dispersing agent, and further comprises a styrene-polyoxyethylene ether copolymer.

2. The prothioconazole-epoxiconazole suspension concentrate according to claim 1, characterized in that The mass ratio of the magnesium aluminum silicate to the xanthan gum is (2-10):

1.

3. The prothioconazole-epoxiconazole suspension concentrate according to claim 2, characterized in that The viscosity of the magnesium aluminum silicate at 25° C., 3# rotor, and 60 rpm is 500-2000 mPa·s.

4. The prothioconazole-epoxiconazole suspension concentrate according to claim 1, characterized in that The antifreeze agent is selected from at least one of ethylene glycol, propylene glycol, glycerol and sodium chloride.

5. The prothioconazole-epoxiconazole suspension concentrate according to claim 1, characterized in that The organic silicones include at least polydimethylsiloxane.

6. A method for preparing the prothioconazole-epoxiconazole suspension concentrate according to any one of claims 1 to 5, characterized in that: At least the following steps are included: Deionized water, wetting dispersant and 20-40wt% of the total amount of silicones are added into a container and shear dispersed to obtain dispersion A; prothioconazole technical and fluopicolide technical are added into dispersion A and stirred and dispersed to obtain dispersion B; 20-40wt% of the total amount of xanthan gum and 20-40wt% of the total amount of antifreeze are stirred and mixed, and magnesium aluminum silicate are added into dispersion B and shear dispersed to obtain dispersion C, 20-40wt% of the total amount of silicones are added and stirred and dispersed, and then sand milled; the particle size D90 is controlled to be less than 3.5μm during sand milling, and after the sand milling, the sample is first sent for wet screening. After the wet screening is qualified, the remaining silicones, preservatives and the mixture of the remaining xanthan gum and the remaining antifreeze are added and shear dispersed to obtain prothioconazole fluopicolide suspension.

7. The method for preparing the prothioconazole-epoxiconazole suspension concentrate according to claim 6, characterized in that: During the sand milling, the particle size D90 is controlled to be less than 1 μm.

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