A synergistic bactericidal water suspension and a method for preparing the same

Abstract

The present application relates to the technical field of pesticides, especially to the field of IPC A01N43, further to a synergistic fungicidal water suspending agent and a preparation method thereof, which comprises the following raw materials in percentage by mass: raw pesticide 5-50%, surfactant 2.5-10%, antifreezing agent 2-8%, suspending agent 0.1-0.6%, preservative 0.05-0.2%, thickening agent 0.05-0.3%, defoaming agent 0.01-0.2%, and deionized water to make up the rest.The water suspending agent prepared by the present application has high drug efficacy, stable content of effective components, synergistic effect of two components, reduced use amount of single component, and alleviated use pressure on the environment; the control effect on wheat scab is 70-90%.

Description

Technical Field

[0001] This invention relates to the field of pesticide technology, particularly to the field of IPC A01N43, and further to an aqueous suspension for enhancing bactericidal activity and its preparation method. Background Technology

[0002] With changes in farming practices and global warming, the frequency and severity of wheat scab are gradually increasing. It not only easily leads to problems such as reduced wheat yield and decreased quality, but also poses a threat to the health of humans and livestock due to the various toxins produced by the wheat scab fungus.

[0003] Chinese patent CN 115251069 A discloses a method for preparing and applying prothioconazole nanoparticles (PTC@Fluo-MSNs). The preparation method is as follows: (1) Based on the surface modification of hydrophilic groups combined with carbon dot fluorescence, carbon quantum dot modified mesoporous silica carbon quantum dot materials (Fluo-MSNs) are prepared by sol-gel method and high-temperature calcination; (2) A prothioconazole solution of a certain concentration is prepared with dichloromethane, the above-prepared mesoporous silica carbon quantum dot material is added, stirred and allowed to stand, centrifuged and washed, and the resulting solid is dried to obtain prothioconazole nanoparticles. The prepared nanoparticles can load and release prothioconazole, and can be used for crop sterilization, inhibiting wheat scab, soybean root rot, soybean root rot and soybean blight. However, the synthesis process of this technical solution is relatively complex and the preparation cost is high.

[0004] Chinese patent CN 201310043939 discloses a fungicide composition containing carbendazim and pyraclostrobin, wherein the mass ratio of carbendazim to pyraclostrobin is 20:1 to 1:20. This fungicide composition has good control effects on fungal diseases of crops such as wheat scab. The combined application of the two agents can reduce the amount of pesticide used, effectively reduce ecological damage and environmental pollution, and improve crop yield and quality. Both carbendazim and pyraclostrobin in this invention are of low toxicity and safe for humans, animals, and beneficial organisms; they can delay the development of resistance to single agents. However, due to the high resistance level of wheat scab to carbendazim, the main active ingredient in this technical solution is carbendazim, and under normal dosage, scab toxin cannot be effectively controlled. Summary of the Invention

[0005] To address the aforementioned technical problems, the first aspect of this invention provides an aqueous suspension for enhancing bactericidal efficacy. The raw materials, by mass percentage, include: 5-50% technical grade drug, 2.5-10% surfactant, 2-8% antifreeze, 0.1-0.6% suspending agent, 0.05-0.2% preservative, 0.05-0.3% thickener, 0.01-0.2% defoamer, and deionized water to make up the balance.

[0006] In some preferred embodiments, the active ingredient is selected from one or more combinations of thiophanate-methyl, tebuconazole, tricyclazole, triadimefon, and pyraclostrobin.

[0007] Preferably, the active ingredient is a combination of thiophanate-methyl and tebuconazole.

[0008] More preferably, the mass ratio of thiophanate-methyl to tebuconazole is (30-40):(4-6).

[0009] More preferably, the mass ratio of thiophanate-methyl to tebuconazole is 35:5.

[0010] Isotriazole is a novel, broad-spectrum systemic triazole fungicide jointly developed by Kureha Chemical Co., Ltd. of Japan and Shell (later American Cyano Corporation, now BASF). Its mechanism of action is as an inhibitor of ergosterol biosynthesis C-14 demethylase. The technical grade contains two isomers, exhibiting good fungicidal activity. Isotriazole has good thermal and hydrolytic stability; it is low in toxicity to non-target organisms, requires low dosage, does not easily penetrate into the soil, has low residue levels, and is environmentally friendly.

[0011] In some preferred embodiments, the surfactant is selected from one or a combination of two of anionic surfactants and nonionic surfactants.

[0012] Preferably, the surfactant is a combination of anionic surfactant and nonionic surfactant.

[0013] In some preferred embodiments, the anionic surfactant is selected from one or more combinations of phenethylphenol polyoxyethylene ether phosphate, phenethylphenol polyoxyethylene ether sulfate, and alkyl polyoxyethylene ether phosphate.

[0014] Preferably, the anionic surfactant is phenylethylphenol polyoxyethylene ether phosphate salt.

[0015] More preferably, the phenylethylphenol polyoxyethylene ether phosphate salt is triphenylethylphenol polyoxyethylene ether phosphate amine salt.

[0016] More preferably, the esterification rate of the triphenylethylphenol polyoxyethylene ether phosphate amine salt is >80%.

[0017] In some preferred embodiments, the nonionic surfactant is selected from one or a combination of two of EO-PO block polyether copolymers, fatty alcohol polyoxyethylene ethers, fatty acid polyoxyethylene esters, fatty amine polyoxyethylene ethers, and styrylphenol polyoxyethylene ethers.

[0018] Preferably, the nonionic surfactant is an EO-PO block polyether copolymer.

[0019] More preferably, the HLB of the EO-PO block polyether copolymer is 12 to 17.

[0020] More preferably, the HLB of the EO-PO block polyether copolymer is 16.

[0021] During the experiment, the applicant discovered that using an EO-PO block polyether copolymer with an HLB value of 16 as a wetting and dispersing agent could improve the dispersion effect of the suspension, especially for D. 90 The use of active pharmaceutical ingredient (API) particles smaller than 1 μm can further improve dispersion and prevent flocculation caused by intermolecular forces, which can lead to lumpy precipitates in severe cases. A possible reason is that while reducing the particle size can increase the adhesion between the API and wheat leaves, excessively small particle sizes can increase particle aggregation and weaken the stability of the suspension. After the EO-PO block polyether copolymer with an HLB value of 16 forms a monolayer adsorption on the particle surface, a new protective layer can be subsequently generated, forming a multilayer overlapping structure that continues to coat the particle surface, further inhibiting ion aggregation. Furthermore, the applicant discovered that using appropriate amounts of ethylene oxide and propylene oxide blocks can increase the dispersion of the API particles, improve grinding wettability, reduce grinding difficulty, and allow the API particles to achieve the ideal particle size.

[0022] In some preferred embodiments, the mass ratio of the anionic surfactant to the nonionic surfactant is (3-5):(1-2).

[0023] Preferably, the mass ratio of the anionic surfactant to the nonionic surfactant is 4:1.5.

[0024] During the experiment, the applicant discovered that when storage temperature changed, the hydrophilicity of the nonionic surfactant EO-PO block polyether copolymer decreased, leading to a decrease in the suspension stability of the active ingredient particles in the aqueous phase. Using triethylphenol polyoxyethylene ether phosphate amine salt with an esterification rate >80% increased the hydrophilicity of the suspended particles. Furthermore, the hydrophilic segments of the triethylphenol polyoxyethylene ether phosphate amine salt could form a gel network structure in the aqueous phase, entangled with each other to form a stable physical connection system, increasing the system's viscosity and thus preventing the sedimentation of suspended particles and avoiding bottoming. The applicant further discovered that when the mass ratio of triethylphenol polyoxyethylene ether phosphate amine salt to EO-PO block polyether copolymer was 4:1.5, the system had low surface tension, allowing it to spread instantly on the leaf surface after spraying. The active ingredient was rapidly absorbed by the leaf cells, achieving good efficacy and effectively controlling wheat scab.

[0025] In some preferred embodiments, the antifreeze is selected from one or more combinations of ethylene glycol, propylene glycol, and glycerol.

[0026] Preferably, the antifreeze is ethylene glycol.

[0027] In some preferred embodiments, the suspending agent is selected from one or more combinations of magnesium aluminum silicate, organobentonite, and attapulgite.

[0028] Preferably, the suspending agent is magnesium aluminum silicate.

[0029] In some preferred embodiments, the preservative is selected from at least one of benzisothiazolin-3-one, potassium sorbate, sodium sorbate, and Kathon.

[0030] Preferably, the preservative is benzisothiazolin-3-one.

[0031] In some preferred embodiments, the thickener is at least one of sodium carboxymethyl cellulose, carboxyethyl cellulose, methyl cellulose, and xanthan gum.

[0032] Preferably, the thickener is xanthan gum.

[0033] In some preferred embodiments, the defoamer is selected from at least one of polydimethylsiloxane, glycerol polyoxypropylene ether, C10-C20 saturated fatty acid compounds, and C8-C10 fatty alcohol compounds.

[0034] Preferably, the defoamer is polydimethylsiloxane.

[0035] Preferably, the defoamer is a combination of polydimethylsiloxane A and polydimethylsiloxane B.

[0036] Preferably, the mass ratio of polydimethylsiloxane A to polydimethylsiloxane B is (4-6):1.

[0037] Preferably, the mass ratio of polydimethylsiloxane A to polydimethylsiloxane B is 5:1.

[0038] Preferably, the viscosity of polydimethylsiloxane A is 400-800 cps (25°C); and the viscosity of polydimethylsiloxane B is 1000-1400 cps (25°C).

[0039] More preferably, the viscosity of polydimethylsiloxane A is 600 cps (25°C); and the viscosity of polydimethylsiloxane B is 1200 cps (25°C).

[0040] During the experiment, the applicant discovered that increasing the amount of surfactant was necessary to reduce the particle size of the active ingredient. However, this increased surfactant usage negatively impacted the foaming performance of the suspension system, resulting in high persistent foaming and hindering pesticide application. The applicant found that using defoamers of different viscosities improved the foaming effect. The applicant hypothesizes that this is because defoamers of varying viscosities penetrate the foam walls, while polydimethylsiloxane spreads easily on the foam surface, thinning the foam walls and causing deformation and breakage. Furthermore, the low-viscosity defoamer has lower surface tension and greater dispersibility in the system, effectively suppressing foam formation and reducing persistent foaming height, thus improving the effectiveness of the suspension.

[0041] In some preferred embodiments, the mass ratio of the surfactant, thickener, and suspending agent is (4-6):(0.1-0.2):(0.2-0.4).

[0042] Preferably, the mass ratio of the surfactant, thickener, and suspending agent is 5.5:0.15:0.3.

[0043] During the experiment, the applicant discovered that when the particle size of the active pharmaceutical ingredient (API) is too small, the particles tend to aggregate and are prone to denaturation after low-temperature storage and heat storage, thus reducing the efficacy of the drug. The applicant found that by controlling the mass ratio of surfactant, thickener, and suspending agent to 5.5:0.15:0.3, the low-temperature and high-temperature stability of the suspension can be improved without the formation of a paste or crystal precipitation. The likely reason is that at the 5.5:0.15:0.3 mass ratio, the surfactant forms a stable physical colloidal system with the aqueous phase. This system, along with the thickener and suspending agent, controls the viscosity of the system within a suitable range, increasing the resistance to API particle aggregation, slowing particle movement, and preventing sedimentation. However, when the preferred mass ratio is exceeded, the viscosity of the system becomes too high, potentially causing the system to form a paste and affecting the pourability of the suspension.

[0044] A second aspect of this invention provides a method for preparing an aqueous suspension with enhanced bactericidal effects, comprising the following steps:

[0045] (1) Weigh each raw material according to its mass percentage;

[0046] (2) Mix the surfactant, defoamer, suspending agent and preservative for 15-20 minutes;

[0047] (3) Add antifreeze and thickener to step (2) and cut 50-70 min;

[0048] (4) Add the original drug to step (3) and shear for 50-70 minutes, then grind it to keep the particle size D90 less than 1 μm;

[0049] (5) After the particle size is qualified, mix again to obtain the final product.

[0050] In some preferred embodiments, the grinding media in step (4) is zirconia beads.

[0051] Preferably, the diameter of the zirconia beads is 0.2 to 2 mm.

[0052] More preferably, the diameter of the zirconium oxide beads is 0.4 to 0.5 mm.

[0053] Beneficial effects:

[0054] 1. This application uses an EO-PO block polyether copolymer with an HLB value of 16 as a wetting and dispersing agent, which can improve the dispersion effect of the suspension, especially for D. 90 The original drug particles with a diameter of less than 1μm can further improve the dispersion effect and avoid flocculation caused by intermolecular forces of small particles, which can lead to the formation of lumpy precipitates in severe cases.

[0055] 2. This application uses triphenylethylphenol polyoxyethylene ether phosphate amine salt with an esterification rate of >80%, which increases the hydrophilicity of suspended particles. Furthermore, the hydrophilic segments of triphenylethylphenol polyoxyethylene ether phosphate amine salt can form a gel network structure in the aqueous phase, entangle with each other to form a stable physical connection system, increase the consistency of the system, thereby avoiding the sedimentation of suspended particles and preventing the formation of bottoming phenomena.

[0056] 3. This application controls the mass ratio of triphenylethylphenol polyoxyethylene ether phosphate amine salt and EO-PO block polyether copolymer to be 4:1.5. The system has low surface tension, and after spraying, it can spread instantly on the leaf surface. The active ingredients are quickly absorbed by the leaf cells, achieving good efficacy and effectively controlling wheat scab.

[0057] 4. The polydimethylsiloxane A with a viscosity of 600 cps (25℃) and polydimethylsiloxane B with a viscosity of 1200 cps (25℃) in this application can suppress foaming in the liquid in the system, thereby reducing the persistent foaming height and improving the performance of the suspending agent.

[0058] 5. By controlling the mass ratio of surfactant, thickener, and suspending agent to 5.5:0.15:0.3, this application can improve the low-temperature stability and high-temperature stability of the suspending agent, and prevent paste formation and crystal precipitation.

[0059] 6. The aqueous suspension prepared in this application has low toxicity to other animals, good exclusivity, and reduces environmental pollution; it has a good spreading effect on leaves, good adhesion to leaves, and can achieve long-lasting bactericidal effect.

[0060] 7. This application uses zirconia beads with a diameter of 0.4 to 0.5 mm as the grinding medium, so that the particle size D90 of the material is less than 1 μm, reaching 0.5 μm. The nanoscale size helps the drug to be adsorbed on the leaf surface, is resistant to wind and rain washout, and enhances its penetration and conduction on the leaves; it is environmentally friendly, easily degraded by the environment, and has high efficacy. Attached Figure Description

[0061] Figure 1 Photographs showing the persistent foaming properties of the aqueous suspension prepared in Example 1.

[0062] In the image: the left image shows the image before 1 minute; the right image shows the image after 1 minute.

[0063] Figure 2 The image shows the sedimentation of the aqueous suspension prepared in Comparative Example 1 at low temperature.

[0064] Figure 3 Photographs of crystal precipitation at low temperature of the aqueous suspension prepared for Comparative Example 2.

[0065] Figure 4 Photographs of the gelatinization of the aqueous suspension prepared in Comparative Example 2 under thermal storage.

[0066] Figure 5 The image shows the crystal precipitation of the aqueous suspension prepared in Comparative Example 3 under thermal storage.

[0067] Figure 6 Photographs of the gelatinization of the aqueous suspension prepared in Comparative Example 4 under thermal storage.

[0068] Figure 7 The image shows the agglomeration of the aqueous suspension prepared in Comparative Example 5 under thermal storage conditions.

[0069] Figure 8 Crystal photographs of the aqueous suspension prepared in Comparative Example 6 at low temperature.

[0070] Figure 9 The image shows the layered structure of the aqueous suspension prepared in Comparative Example 7 at low temperature. Detailed Implementation

[0071] Example 1

[0072] Example 1 provides an aqueous suspension for enhancing bactericidal efficacy. By mass percentage, the raw materials include: 40% technical grade drug, 5.5% surfactant, 4.5% antifreeze, 0.3% suspending agent, 0.15% preservative, 0.15% thickener, 0.12% defoamer, and deionized water to make up the balance.

[0073] The technical grade pesticide is a combination of thiophanate-methyl and tebuconazole; the mass ratio of thiophanate-methyl to tebuconazole is 35:5.

[0074] The surfactant is a combination of anionic and nonionic surfactants.

[0075] The mass ratio of the anionic surfactant to the nonionic surfactant is 4:1.5.

[0076] The anionic surfactant is triphenylethylphenol polyoxyethylene ether phosphate amine salt, and the esterification rate of the triphenylethylphenol polyoxyethylene ether phosphate amine salt is >80%. It was purchased from Jiangsu Kaiyuan Technology Co., Ltd., model: KY518.

[0077] The nonionic surfactant is an EO-PO block polyether copolymer; the EO-PO block polyether copolymer has an HLB of 16 and was purchased from Ningbo Di Co., Ltd., model number: Emulson AG PE.

[0078] The antifreeze is ethylene glycol.

[0079] The suspending agent is magnesium aluminum silicate.

[0080] The preservative is benzisothiazolin-3-one.

[0081] The thickener is xanthan gum.

[0082] The defoamer is a combination of polydimethylsiloxane A and polydimethylsiloxane B; the mass ratio of polydimethylsiloxane A to polydimethylsiloxane B is 5:1.

[0083] The viscosity of polydimethylsiloxane A is 600 cps (25°C), and its model number is Momentive SAG 1522; the viscosity of polydimethylsiloxane B is 1200 cps (25°C), and its model number is Momentive SAG 1572.

[0084] A method for preparing an aqueous suspension with enhanced bactericidal effect includes the following steps:

[0085] (1) Weigh each raw material according to its mass percentage;

[0086] (2) Mix the surfactant, defoamer, suspending agent and preservative for 15 minutes;

[0087] (3) Add antifreeze and thickener to step (2) and cut 60 min;

[0088] (4) Add the original drug to step (3) and shear for 60 min, then perform sand milling to keep the particle size D90 less than 1 μm;

[0089] (5) After the particle size is qualified, mix again to obtain the final product.

[0090] The grinding medium in step (4) is zirconium oxide beads.

[0091] The zirconia beads have a diameter of 0.5 mm.

[0092] Example 2

[0093] Example 2 provides an aqueous suspension for enhancing bactericidal efficacy. By mass percentage, the raw materials include: 35% technical grade drug, 5.0% surfactant, 4.0% antifreeze, 0.2% suspending agent, 0.1% preservative, 0.1% thickener, 0.1% defoamer, and deionized water to make up the balance.

[0094] The technical grade pesticide is a combination of thiophanate-methyl and tebuconazole; the mass ratio of thiophanate-methyl to tebuconazole is 35:5.

[0095] The surfactant is a combination of anionic and nonionic surfactants.

[0096] The mass ratio of the anionic surfactant to the nonionic surfactant is 4:1.5.

[0097] The anionic surfactant is triphenylethylphenol polyoxyethylene ether phosphate amine salt, and the esterification rate of the triphenylethylphenol polyoxyethylene ether phosphate amine salt is >80%. It was purchased from Jiangsu Kaiyuan Technology Co., Ltd., model: KY518.

[0098] The nonionic surfactant is an EO-PO block polyether copolymer; the EO-PO block polyether copolymer has an HLB of 16 and was purchased from Ningbo Di Co., Ltd., model number: Emulson AG PE.

[0099] The antifreeze is ethylene glycol.

[0100] The suspending agent is magnesium aluminum silicate.

[0101] The preservative is benzisothiazolin-3-one.

[0102] The thickener is xanthan gum.

[0103] The defoamer is a combination of polydimethylsiloxane A and polydimethylsiloxane B; the mass ratio of polydimethylsiloxane A to polydimethylsiloxane B is 5:1.

[0104] The viscosity of polydimethylsiloxane A is 600 cps (25°C), and its model number is Momentive SAG 1522; the viscosity of polydimethylsiloxane B is 1200 cps (25°C), and its model number is Momentive SAG 1572.

[0105] A method for preparing an aqueous suspension with enhanced bactericidal effect includes the following steps:

[0106] (1) Weigh each raw material according to its mass percentage;

[0107] (2) Mix the surfactant, defoamer, suspending agent and preservative for 15 minutes;

[0108] (3) Add antifreeze and thickener to step (2) and cut 60 min;

[0109] (4) Add the original drug to step (3) and shear for 60 min, then perform sand milling to keep the particle size D90 less than 1 μm;

[0110] (5) After the particle size is qualified, mix again to obtain the final product.

[0111] The grinding medium in step (4) is zirconium oxide beads.

[0112] The zirconia beads have a diameter of 0.5 mm.

[0113] Comparative Example 1

[0114] Comparative Example 1 provides an aqueous suspension for enhanced bactericidal action, which is implemented in the same way as Example 1, except that triphenylethylphenol polyoxyethylene ether phosphate amine salt is replaced with dodecylbenzene sulfonate ammonium salt, purchased from Nanjing Jierun Technology Co., Ltd., model EC-7030A.

[0115] Comparative Example 2

[0116] Comparative Example 2 provides an aqueous suspension for enhanced bactericidal action. The specific implementation method is the same as that of Example 1, except that the triphenylethylphenol polyoxyethylene ether phosphate amine salt is replaced with phosphate ester, which was purchased from Shanghai Wanjin Additives Co., Ltd., model: WJF-960.

[0117] Comparative Example 3

[0118] Comparative Example 3 provides an aqueous suspension for enhanced bactericidal action. The specific implementation method is the same as that of Example 1, except that triphenylethylphenol polyoxyethylene ether phosphate amine salt is replaced with dodecylbenzene sulfonate, which was purchased from Nanjing Jierun Technology Co., Ltd., model: K12.

[0119] Comparative Example 4

[0120] Comparative Example 4 provides an aqueous suspension for enhanced bactericidal action. The specific implementation method is the same as that of Example 1, except that triphenylethylphenol polyoxyethylene ether phosphate amine salt is replaced with alkylphenol polyoxyethylene ether, which was purchased from Jiangsu Haian Petrochemical Plant, model: APEO.

[0121] Comparative Example 5

[0122] Comparative Example 5 provides an aqueous suspension agent for enhanced bactericidal action. The specific implementation method is the same as that of Example 1, except that the EO-PO block polyether copolymer is replaced with Ethylan 324 (HLB value 8.0), which was purchased from Nanjing Jierun Technology Co., Ltd.

[0123] Comparative Example 6

[0124] Comparative Example 6 provides an aqueous suspension agent for enhanced bactericidal action. The specific implementation method is the same as that of Example 1, except that the EO-PO block polyether copolymer is replaced with polyoxyethylene polyoxypropylene copolymer, which was purchased from Shanghai Jieshi Chemical Co., Ltd., model: YUS-5050PB.

[0125] Comparative Example 7

[0126] Comparative Example 7 provides an aqueous suspension agent for enhanced bactericidal action. The specific implementation method is the same as that of Example 1, except that the EO-PO block polyether copolymer is replaced with a polyether copolymer purchased from Wuxi Yijingfeng Technology Co., Ltd., model: 8070.

[0127] Performance testing:

[0128] 1. Physicochemical property testing

[0129] The aqueous suspensions prepared in Examples 1-2 and Comparative Examples 1-7 were subjected to low-temperature and thermal storage stability tests according to GB / T 19137-2003 standard. The test indicators are shown in Table 1, and the results are shown in Table 2. Figures 1-9 .

[0130] Determination of the mass fraction of thiophanate-methyl:

[0131] The sample was dissolved in methanol, using a mobile phase of methanol + water = 65 + 35, and a solution of C was used. 18 A stainless steel column filled with thiophanate-methyl and an ultraviolet detector with adjustable wavelength were used to separate and determine thiophanate-methyl in the sample by high performance liquid chromatography.

[0132] Mobile phase: methanol + water = 65 + 35 (V / V). The mobile phase is filtered through a 0.45 μm pore size membrane and degassed in an ultrasonic bath for 10 min.

[0133] Chromatographic column: Φ4.6mm×150mm stainless steel column, packed with C20. 18 / 5μm is a stainless steel column filled with material.

[0134] Flow rate: 0.8 mL / min

[0135] Column temperature: Room temperature (temperature difference not exceeding 2℃)

[0136] Detection wavelength: 269nm

[0137] Injection volume: 5 μL

[0138] Retention time: 3.9 min for thiophanate-methyl.

[0139] Determination of the mass fraction of tebuconazole:

[0140] The sample was dissolved in acetonitrile, with acetonitrile + water = 50 + 50 as the mobile phase, and C was used. 18 A stainless steel column filled with thiamethoxam and an ultraviolet detector with adjustable wavelength were used to separate and determine thiamethoxam in the sample by high performance liquid chromatography.

[0141] Mobile phase: methanol + water = 65 + 35 (V / V). The mobile phase is filtered through a 0.45 μm pore size membrane and degassed in an ultrasonic bath for 10 min.

[0142] Chromatographic column: Φ4.6mm×250mm stainless steel column, packed with C2O4. 18 / 5μm is a stainless steel column filled with material.

[0143] Flow rate: 1.0 mL / min

[0144] Column temperature: Room temperature (temperature difference not exceeding 2℃)

[0145] Detection wavelength: 220nm

[0146] Injection volume: 5 μL

[0147] Retention time: approximately 20.2 min for the trans form of tebuconazole and approximately 21.4 min for the cis form of tebuconazole.

[0148] 2. Toxicological testing

[0149] The suspension prepared in Example 1 was subjected to toxicological tests in accordance with GB 15670-1995 standard, and the results are shown in Table 3.

[0150] 3. Ecological and environmental impact experiment

[0151] The results of the impact of the aqueous suspension prepared in Example 1 on the ecological environment are shown in Table 4.

[0152] 3. The results of the field efficacy experiment are shown in Table 5.

[0153] Test results:

[0154] Table 1

[0155]

[0156]

[0157] Table 2

[0158] Example 1 qualified qualified Example 2 qualified qualified Comparative Example 1 Unqualified qualified Comparative Example 2 Crystals precipitate ointment Comparative Example 3 qualified Crystals precipitate Comparative Example 4 Unqualified ointment Comparative Example 5 qualified There are clumps Comparative Example 6 Crystals precipitate qualified Comparative Example 7 qualified Layering

[0159] The aqueous suspension prepared in Example 1 was a white liquid with a slightly irritating odor; its density was 1.1644 g / mL (20℃); the viscosity test results were: 20℃: 698.4 mPa·s (rotor model: 62, speed 12 rpm), 598.4 mPa·s (rotor model: 62, speed 30 rpm).

[0160] Table 3

[0161]

[0162] Table 4

[0163]

[0164] Table 5

[0165]

[0166]

Claims

1. A water suspension agent for enhanced bactericidal effect, characterized in that, By weight percentage, the raw materials include: technical grade drug 5-50%, surfactant 2.5-10%, antifreeze 2-8%, suspending agent 0.1-0.6%, preservative 0.05-0.2%, thickener 0.05-0.3%, defoamer 0.01-0.2%, and deionized water to make up the balance; The technical material is a combination of thiophanate-methyl and tebuconazole; the mass ratio of thiophanate-methyl to tebuconazole is (30~40):(4~6); The surfactant is a combination of anionic and nonionic surfactants, wherein the anionic surfactant is phenylethylphenol polyoxyethylene ether phosphate salt and the nonionic surfactant is EO-PO block polyether copolymer; The HLB of the EO-PO block polyether copolymer is 12~17; The mass ratio of the anionic surfactant to the nonionic surfactant is (3~5):(1~2); The preparation method of the bactericidal aqueous suspension includes the following steps: (1) Weigh each raw material according to its mass percentage; (2) Mix the surfactant, defoamer, suspending agent and preservative for 15-20 minutes; (3) Add antifreeze and thickener to step (2) and cut 50-70 min; (4) Add the original drug to step (3) and shear for 50-70 minutes, then perform sand milling to keep the particle size D90 less than 1μm; (5) After the particle size is qualified, mix again to obtain the final product.

2. A method for preparing an aqueous suspension agent with synergistic bactericidal effect according to claim 1, characterized in that, Includes the following steps: (1) Weigh each raw material according to its mass percentage; (2) Mix the surfactant, defoamer, suspending agent and preservative for 15-20 minutes; (3) Add antifreeze and thickener to step (2) and cut 50-70 min; (4) Add the original drug to step (3) and shear for 50-70 minutes, then perform sand milling to keep the particle size D90 less than 1μm; (5) After the particle size is qualified, mix again to obtain the final product.

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