A suspension containing pyroxasulfone and flumioxazin and a method for preparing the same

Abstract

The present application provides a kind of suspension agent containing topramezone and flumioxazine, comprising: active ingredient, dispersing agent, wetting agent, thickening agent and antifoaming agent;The active ingredient includes topramezone and flumioxazine.The topramezone and flumioxazine suspension agent provided by the present application has high content, which can exceed 40%, which is beneficial to reduce the dosage and the frequency of administration, thereby reducing the cost.Through the preferred auxiliary agent, the stability of the product is improved, which can withstand-15 DEG C to 65 DEG C high-low temperature interval, effectively solves the influence of environmental change in the transportation process, avoids the caking, creaming, particle size growth, water separation and other product quality problems.At the same time, it can withstand C water, D water, 3 WHO water and other different water quality, meet the use of different countries and regions, which is beneficial to wide range of popularization and application.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of pesticides, and particularly relates to a suspension agent containing pyroxasulfone and flumioxazin and a preparation method thereof. BACKGROUND

[0002] Pyroxasulfone, chemical name: 3-[5-(difluoromethoxy)-1-methyl-3-(trifluoromethyl) pyrazol-4-ylmethylsulfonyl]-4,5-dihydro-5,5-dimethyl-1,2-isoxazole, belongs to a new type of isoxazole herbicide, which is widely used in crops, and is mainly used in corn, cotton, peanuts, wheat, sunflower and the like, and can effectively prevent and control grass weeds such as Digitaria, Crabgrass, Echinochloa and the like, and broadleaf weeds such as Amaranthus, Datura, Solanum, Abutilon and the like.

[0003] Flumioxazin, chemical name: alpha-cyano-4-fluoro-3-phenoxybenzyl-3-(beta,4-dichlorostyryl)-2,2-dimethylcyclopropane carboxylate, belongs to a cyclic imine herbicide, which is used for preventing and controlling annual broadleaf weeds and grass weeds such as soybean, cotton, grape, peanut and the like.

[0004] The herbicide varieties containing a single active ingredient have different degrees of defects in the prevention and control of agricultural weeds, for example, the herbicidal spectrum is narrow, weeds are prone to drug resistance after continuous use, and the use times are too many to cause environmental pollution.

[0005] The combination of pyroxasulfone and flumioxazin has been proved to have the effects of synergistic effect, expanded herbicidal spectrum and delayed weed resistance. However, for the high-content suspension agent product containing pyroxasulfone and flumioxazin, the quality is unstable, the product is easily affected by environmental changes during sea transportation, and the product is prone to caking, creaming, particle size growth, water separation and the like under high temperature, and the product is prone to crystallization under low temperature, which seriously affects the efficacy. In the face of complex environment, the product is prone to water separation, even flocculation and precipitation. In the use process, the product is greatly affected by different water qualities, for example, the product is not resistant to 3WHO water, which is not conducive to the use and promotion of the product. SUMMARY

[0006] Therefore, the present application aims to solve the technical problem, and provides a suspension agent containing pyroxasulfone and flumioxazin and a preparation method thereof, and the prepared suspension agent has high stability.

[0007] To achieve the above-mentioned purpose, the present application provides a suspension agent containing pyroxasulfone and flumioxazin, which comprises: active ingredients, dispersants, wetting agents, thickening agents and defoaming agents.

[0008] The active ingredients comprise pyroxasulfone and flumioxazin.

[0009] Preferably, the suspension of the active ingredient of the sulfentrazone and the flumioxazin further comprises: an antifreeze agent and / or a preservative.

[0010] Preferably, the suspension of the active ingredient of the sulfentrazone and the flumioxazin comprises, in terms of mass content:

[0011] active ingredient 10% to 65%, dispersant 1% to 6%, wetting agent 1% to 3%, thickening agent 0.2% to 2%, defoaming agent 0.2% to 3%, antifreeze agent 2% to 10%, preservative 0.1% to 2%, deionized water to 100%;

[0012] The active ingredient comprises the sulfentrazone and the flumioxazin;

[0013] The mass ratio of the sulfentrazone and the flumioxazin is 1:(0.01 to 90).

[0014] Preferably, the dispersant is selected from one or more of the following: high molecular polymer, lignin sulfonate, naphthalene sulfonate, styrene acrylic acid copolymer sodium salt, triphenyl styryl phenol polyoxyethylene ether sulfate ammonium salt, maleic rosin block polyether sulfonic acid ammonium salt, fatty alcohol polyoxyethylene ether phosphate, fatty alcohol polyoxyethylene ether phosphate, methyl methacrylate copolymer polyoxyethylene ether, alkyl naphthalene formaldehyde condensate sulfonate, dioctyl succinate sodium sulfonate, and castor oil polyoxyethylene ether phosphate.

[0015] Preferably, the dispersant is composed of a first dispersant, a second dispersant, and a third dispersant;

[0016] The first dispersant is selected from styrene acrylic acid copolymer sodium salt, methyl methacrylate copolymer polyoxyethylene ether, or lignin sulfonate;

[0017] The second dispersant is selected from triphenyl styryl phenol polyoxyethylene ether sulfate ammonium salt or alkyl naphthalene formaldehyde condensate sulfonate;

[0018] The third dispersant is selected from maleic rosin block polyether sulfonic acid ammonium salt or fatty alcohol polyoxyethylene ether phosphate.

[0019] Preferably, the mass ratio of the first dispersant, the second dispersant, and the third dispersant is (0.1 to 5):(0.1 to 5):1.

[0020] Preferably, the wetting agent is selected from one or more of the following: propylene oxide-ethylene oxide block polyether, fatty alcohol polyoxyethylene polyoxypropylene ether, dioctyl succinate sodium sulfonate.

[0021] Preferably, the thickening agent is selected from one or more of the following: methyl cellulose, organic bentonite, xanthan gum, ordinary white carbon black, and sodium polyacrylate.

[0022] Preferably, the thickening agent is composed of a first thickening agent and a second thickening agent.

[0023] The first thickening agent is selected from common white carbon black.

[0024] The second thickening agent is selected from xanthan gum.

[0025] Preferably, the mass ratio of the first thickening agent and the second thickening agent is (0.1-0.5):(0.1-0.5).

[0026] Preferably, the defoaming agent is selected from one or more of polyether defoaming agent, silicone defoaming agent and polyether modified polysiloxane defoaming agent.

[0027] Preferably, the antifreeze agent is selected from one or more of urea, potassium chloride, ethylene glycol, propylene glycol, glycerol, polyethylene glycol, sorbitol and sodium chloride.

[0028] The preservative is selected from one or more of carboxin, formaldehyde and sodium benzoate.

[0029] The present application provides a preparation method of the above-mentioned suspension containing sulfentrazone and flumioxazine, comprising the following steps:

[0030] 1. Preparation of pulverized slurry

[0031] First, disperse the dispersant, wetting agent, defoaming agent and preservative in part of the water, then disperse sulfentrazone and flumioxazine therein, disperse by high-speed shearing of a shearing machine, pulverize and grind the mixture to a particle size D90 of less than 5 μm, and obtain a pulverized slurry;

[0032] 2. Preparation of dispersion medium

[0033] Disperse the thickening agent and antifreeze agent in the remaining water to obtain a dispersion medium;

[0034] 3. Preparation of aqueous suspension

[0035] Mix the above-mentioned pulverized slurry and dispersion medium, disperse by high-speed shearing of a shearing machine, and obtain a suspension of sulfentrazone and flumioxazine.

[0036] Compared with the prior art, the present application provides a suspension containing sulfentrazone and flumioxazine, which comprises: active ingredients, dispersants, wetting agents, thickening agents and defoaming agents; the active ingredients include sulfentrazone and flumioxazine.

[0037] The sulcotrion and flumioxazin suspension agent provided by the application has a high content, which can be more than 40%, is beneficial to reducing the dosage and the frequency of application, and thus reduces the cost of the pesticide. By using the preferred auxiliary agent, the stability of the product is improved, the product can withstand a high and low temperature interval of-15 DEG C to 65 DEG C, effectively solves the influence of environmental changes in the transportation process, and avoids the problems of caking, creaming, particle size growth, water separation and the like. Meanwhile, the product can withstand different water qualities such as C water, D water and 3 WHO water, meets the use of different countries and regions, and is beneficial to wide popularization and application. DETAILED DESCRIPTION

[0038] The application provides a suspension agent containing sulcotrion and flumioxazin, which comprises active ingredients, dispersants, wetting agents, thickening agents and defoaming agents.

[0039] The active ingredients comprise sulcotrion and flumioxazin.

[0040] The application takes sulcotrion and flumioxazin as the active ingredients.

[0041] Sulcotrion: white solid in appearance; molecular mass: 391.32; melting point: 157.6 DEG C; logP: 3.30 (25 DEG C); density: 1.598 g / cm 3 . Solubility in water: 0.17 mg / L (25 DEG C). At 25 DEG C, sulcotrion is difficult to hydrolyze under the conditions of pH 4, 7 and 9, and the half-lives are 138.6 d, 115.5 d and 115.5 d respectively. The anaerobic condition of water accumulation is more conducive to the degradation of sulcotrion in soil; the photolysis type of sulcotrion on the surface of soil belongs to difficult photolysis, and the half-life of degradation is 231 h. Sulcotrion is easy to photolyze in organic solvents such as ethyl acetate and acetonitrile, and is difficult to photolyze in acetone, and the half-lives of degradation are 1.43 h, 2.38 h and 21.66 h respectively.

[0042] Flumioxazin: white crystal in appearance; molecular mass: 354.33; melting point: 201.83-203.83 DEG C; logP: 2.55 (25 DEG C); density: 1.48 g / cm 3 . Solubility (g / L, 25 DEG C): water 1.79 x 10 -3 , acetone 17, acetonitrile 32.3, ethyl acetate 17.8, dichloromethane 191, hexane 0.025, methanol 1.6, n-octanol 0.16.

[0043] The Log P of both metrafenone and propanil is high, and if the dispersant is not properly selected, problems such as particle size increase, stickiness, creaming, caking and the like are prone to occur during hot storage. Meanwhile, the density of both is large, and when high content formulations are prepared, problems such as water separation, layering and creaming at the bottom are prone to occur. Therefore, it is difficult to prepare a water dispersible concentrate by mixing the two, and the active ingredient particles are prone to separate and agglomerate in the suspension dispersion system. The present application has carried out a large amount of screening work on the auxiliary system, and finally obtained a system with the best matching degree among the components, especially the screening and combination of dispersants and thickeners, which greatly reduces the processing difficulty of the dosage form, improves the stability of the dosage form, has the advantages of good dispersing performance and high suspension rate, and effectively solves a series of problems such as creaming, flocculation, particle size increase and caking during sample storage.

[0044] The mass content of the active ingredient is preferably 10% to 65%, more preferably 20% to 50%, and can be 10.5%, 22%, 24%, 32%, 36%, 40%, 41.6%, 48%, 55%, 65%, or a range value with any of the above values as the upper limit or lower limit.

[0045] The mass ratio of metrafenone and propanil is preferably 1:(0.01-90), more preferably 1:(0.04-20), and further preferably 1:(0.2-5), and can be 1:0.048, 1:0.1, 1:0.2, 1:0.3, 1:0.4, 1:1, 1:2, 1:3, 1:4, 1:5, 1:10, 1:20, or a range value with any of the above values as the upper limit or lower limit.

[0046] The mass content of metrafenone is preferably 1% to 70%, more preferably 4% to 40%, and can be 0.5%, 2%, 4%, 8%, 18%, 29%, 30%, 40%, 50%, 62%, or a range value with any of the above values as the upper limit or lower limit.

[0047] The mass content of propanil is preferably 1% to 30%, more preferably 8% to 24%, and can be 3%, 5%, 8%, 10%, 12.6%, 18%, 20%, 24%, or a range value with any of the above values as the upper limit or lower limit.

[0048] The mass content of the dispersant is preferably 1% to 6%, more preferably 3% to 6%, and can be 5% or 6%, or a range value with any of the above values as the upper limit or lower limit.

[0049] The dispersant is preferably one or more of a high molecular polymer, a lignin sulfonate, a naphthalene sulfonate, a sodium salt of a styrene acrylic copolymer, an ammonium salt of a tristyrylphenol polyoxyethylene ether sulfate, an ammonium salt of a maleic rosin block polyether sulfonate, a fatty alcohol polyoxyethylene ether phosphate, a fatty alcohol polyoxyethylene ether phosphate, a methyl methacrylate copolymer polyoxyethylene ether, an alkyl naphthalene formaldehyde condensate sulfonate, a sodium salt of dioctyl succinate sulfonate, and a castor oil polyoxyethylene ether phosphate; more preferably one or more of a sodium salt of a styrene acrylic copolymer, a naphthalene sulfonate, an ammonium salt of a maleic rosin block polyether sulfonate, and an ammonium salt of a tristyrylphenol polyoxyethylene ether sulfate.

[0050] Further preferably, the dispersant is composed of a first dispersant, a second dispersant, and a third dispersant; the first dispersant is selected from a sodium salt of a styrene acrylic copolymer, a methyl methacrylate copolymer polyoxyethylene ether, or a lignin sulfonate; the second dispersant is selected from an ammonium salt of a tristyrylphenol polyoxyethylene ether sulfate or an alkyl naphthalene formaldehyde condensate sulfonate; and the third dispersant is selected from an ammonium salt of a maleic rosin block polyether sulfonate or a fatty alcohol polyoxyethylene ether phosphate.

[0051] The mass ratio of the first dispersant, the second dispersant, and the third dispersant is preferably (0.1-5):(0.1-5):1, more preferably (1-5):(1-5):1, further preferably (0.5-3):(0.3-2):1, and specifically can be 3:2:1, 1:1:1, 1:3:2, 2:1:3, or a range value with any of the above values as the upper limit or lower limit.

[0052] In some specific embodiments of the present application, the dispersant is a sodium salt of a styrene acrylic copolymer, an ammonium salt of a tristyrylphenol polyoxyethylene ether sulfate, and an ammonium salt of a maleic rosin block polyether sulfonate.

[0053] The mass ratio of the sodium salt of a styrene acrylic copolymer, the ammonium salt of a tristyrylphenol polyoxyethylene ether sulfate, and the ammonium salt of a maleic rosin block polyether sulfonate is preferably 3:2:1, 1:1:1, 1:3:2, or 2:1:3, and further preferably 3:2:1.

[0054] Preferably, the dispersant is 3% by mass of a sodium salt of a styrene acrylic copolymer, 2% by mass of an ammonium salt of a tristyrylphenol polyoxyethylene ether sulfate, and 1% by mass of an ammonium salt of a maleic rosin block polyether sulfonate.

[0055] Preferably, the dispersant is 2% by mass of a sodium salt of a styrene acrylic copolymer, 2% by mass of an ammonium salt of a tristyrylphenol polyoxyethylene ether sulfate, and 2% by mass of an ammonium salt of a maleic rosin block polyether sulfonate.

[0056] Preferably, the dispersant is styrene acrylic copolymer sodium salt 1%, triphenyl styryl phenol polyoxyethylene ether sulfate ammonium salt 3% and maleic rosin block polyether sulfonic acid ammonium salt 2% by mass content.

[0057] Preferably, the dispersant is styrene acrylic copolymer sodium salt 2%, triphenyl styryl phenol polyoxyethylene ether sulfate ammonium salt 1% and maleic rosin block polyether sulfonic acid ammonium salt 3% by mass content.

[0058] In some embodiments of the present application, the dispersant is methyl methacrylate copolymer polyoxyethylene ether, triphenyl styryl phenol polyoxyethylene ether sulfate ammonium salt and maleic rosin block polyether sulfonic acid ammonium salt.

[0059] The mass ratio of the methyl methacrylate copolymer polyoxyethylene ether, triphenyl styryl phenol polyoxyethylene ether sulfate ammonium salt and maleic rosin block polyether sulfonic acid ammonium salt is preferably 3:2:1, 1:1:1, 1:3:2 or 2:1:3, and further preferably 3:2:1.

[0060] Preferably, the dispersant is methyl methacrylate copolymer polyoxyethylene ether 3%, triphenyl styryl phenol polyoxyethylene ether sulfate ammonium salt 2% and maleic rosin block polyether sulfonic acid ammonium salt 1% by mass content.

[0061] In some embodiments of the present application, the dispersant is lignin sulfonate, triphenyl styryl phenol polyoxyethylene ether sulfate ammonium salt and maleic rosin block polyether sulfonic acid ammonium salt.

[0062] The mass ratio of the lignin sulfonate, triphenyl styryl phenol polyoxyethylene ether sulfate ammonium salt and maleic rosin block polyether sulfonic acid ammonium salt is preferably 3:2:1, 1:1:1, 1:3:2 or 2:1:3, and further preferably 3:2:1.

[0063] Preferably, the dispersant is lignin sulfonate 3%, triphenyl styryl phenol polyoxyethylene ether sulfate ammonium salt 2% and maleic rosin block polyether sulfonic acid ammonium salt 1% by mass content.

[0064] The present application forms a synergistic effect by using the first dispersant, the second dispersant and the third dispersant in combination, and maximizes the stability of the suspending agent, especially the high-low temperature performance and the performance after high-temperature storage.

[0065] The mass content of the wetting agent is preferably 1% to 3%, more preferably 1% to 2%, and specifically can be 1%, 1.5%, 2%, or a range value with any of the above values as the upper limit or lower limit.

[0066] The wetting agent is preferably one or more of propylene oxide-ethylene oxide block polyether, fatty alcohol polyoxyethylene polyoxypropylene ether, sodium dioctyl sulfosuccinate.

[0067] The mass content of the thickening agent is preferably 0.2% to 2%, more preferably 0.2% to 0.8%, and specifically can be 0.2%, 0.3%, 0.4%, 0.45%, 0.5%, 0.6%, 0.7%, or a range value with any of the above values as the upper limit or lower limit.

[0068] The thickening agent is preferably one or more of methyl cellulose, organic bentonite, xanthan gum, ordinary white carbon black, and sodium polyacrylate, and more preferably one or more of xanthan gum and ordinary white carbon black.

[0069] Further preferably, the thickening agent is composed of a first thickening agent and a second thickening agent; the first thickening agent is selected from ordinary white carbon black; and the second thickening agent is selected from xanthan gum.

[0070] The mass ratio of the first thickening agent to the second thickening agent is preferably (0.1 to 0.5):(0.1 to 0.5), and more preferably 1:(0.4 to 0.5), and specifically can be 1:0.5 or 1:0.4.

[0071] In some embodiments of the present application, the thickening agent is 0.5% of ordinary white carbon black and 0.2% of xanthan gum in terms of mass content.

[0072] In some embodiments of the present application, the thickening agent is 0.2% of ordinary white carbon black and 0.1% of xanthan gum in terms of mass content.

[0073] In some embodiments of the present application, the thickening agent is 0.3% of ordinary white carbon black and 0.15% of xanthan gum in terms of mass content.

[0074] The present application uses the above-mentioned thickening agent combination, which exerts a synergistic effect of the two, and the prepared suspension agent has high stability.

[0075] The mass content of the defoaming agent is preferably 0.2% to 3%, more preferably 0.1% to 0.5%, and specifically can be 0.2%, 0.5%, 1%, 3%, or a range value with any of the above values as the upper limit or lower limit.

[0076] The defoaming agent is preferably one or more of polyether defoaming agent, silicone defoaming agent, and polyether-modified polysiloxane defoaming agent, and more preferably silicone defoaming agent.

[0077] The mass content of the silicone defoaming agent is preferably 0.2%.

[0078] Preferably, the suspension agent further comprises an antifreeze agent and / or a preservative.

[0079] The mass content of the antifreeze is preferably 2% to 10%, more preferably 3% to 5%, and specifically can be 2%, 3%, 4%, 5%, or a range value with any of the above values as the upper limit or lower limit.

[0080] The antifreeze is preferably one or more of urea, potassium chloride, ethylene glycol, propylene glycol, glycerol, polyethylene glycol, sorbitol, and sodium chloride; and more preferably ethylene glycol.

[0081] The mass content of the ethylene glycol is preferably 3%.

[0082] The antifreeze improves the stability of the product under low temperature conditions.

[0083] The mass content of the preservative is preferably 0.1% to 2%, more preferably 0.1% to 1%, and further preferably 0.1% to 0.15%, and specifically can be 0.1%, 0.2%, 0.3%, 0.5%, 1%, 2%, or a range value with any of the above values as the upper limit or lower limit.

[0084] The preservative is preferably one or more of carboxin, formaldehyde, and sodium benzoate, and more preferably carboxin.

[0085] The mass content of the carboxin is preferably 0.1%.

[0086] When the suspending agent is a water suspending agent, deionized water is used to make up the system to 100%.

[0087] Preferably, the suspending agent containing both metrafenone and flumioxazine includes, by mass content:

[0088] active ingredient 10% to 65%, dispersing agent 1% to 6%, wetting agent 1% to 3%, thickening agent 0.2% to 2%, defoaming agent 0.2% to 3%, antifreeze 2% to 10%, preservative 0.1% to 2%, and deionized water to make up 100%;

[0089] The active ingredient includes metrafenone and flumioxazine.

[0090] The mass ratio of metrafenone to flumioxazine is 1:(0.01 to 90).

[0091] The present application provides a preparation method of the above suspending agent containing both metrafenone and flumioxazine, including the following steps:

[0092] 1. Preparation of the pulverized slurry

[0093] The dispersant, wetting agent, antifoaming agent and preservative are first dispersed completely in part of the water, then the metrafenone and flumioxazin are dispersed in the water, and the mixture is sheared by a shearing machine at high speed to disperse the mixture, and the sheared mixture is crushed and ground to a particle size D90 of less than 5 μm to obtain a crushed slurry;

[0094] 2. Dispersion medium preparation

[0095] The thickening agent and antifreezing agent are dispersed in the remaining water to obtain a dispersion medium;

[0096] 3. Preparation of the aqueous suspension

[0097] The crushed slurry and the dispersion medium are mixed and sheared by a shearing machine at high speed to obtain a suspension of the metrafenone and flumioxazin.

[0098] Preferably, the metrafenone and flumioxazin are added under high-speed shearing, and the shearing time in step 1 is preferably 10-30 min.

[0099] The shearing speed is preferably 1000-10000 r / min.

[0100] The crushing in step 1 is preferably wet crushing by a sand mill.

[0101] The shearing time in step 3 is preferably 10-30 min.

[0102] The shearing speed is preferably 1000-10000 r / min.

[0103] In the preparation method, the grinding in step 1 can be performed by any grinding method disclosed in the prior art, for example, grinding under a zirconia bead sand mill medium. After grinding, a laser particle size distribution instrument is used for detection until the particle size D90 is less than 5 μm.

[0104] To further illustrate the present application, the suspension containing metrafenone and flumioxazin and the preparation method thereof provided by the present application are described in detail below with reference to the examples.

[0105] Unless otherwise specified, the following percentage content is a weight percentage content.

[0106] Examples 1-10

[0107] 1. Preparation of the crushed slurry

[0108] The dispersant, wetting agent, antifoaming agent and preservative are first dispersed completely in part of the water, then the metrafenone and flumioxazin are dispersed in the water, and the mixture is sheared by a shearing machine at high speed to disperse the mixture, and the sheared mixture is crushed and ground to a particle size D90 of less than 5 μm to obtain a crushed slurry.

[0109] 2. Modulation of the dispersion medium

[0110] Disperse thickening agent and antifreezing agent in the remaining water to obtain the dispersion medium.

[0111] 3. Modulation of the aqueous suspending pesticide composition

[0112] Mix the above crushed slurry and dispersion medium, and disperse by high-speed shearing of a shearing machine to obtain the suspending agent of mefenpyr-diethyl and butyracarb.

[0113] The proportions of each material are shown in Tables 1-2.

[0114] Table 1 Proportions of each raw material in Examples 1-5

[0115]

[0116] Table 2 Proportions of each raw material in Examples 6-10

[0117]

[0118] Comparative Example 1

[0119] According to the proportions in Table 3, the aqueous suspending agent containing mefenpyr-diethyl and butyracarb was prepared by the same method as in Examples 1-10.

[0120] Table 3 Proportions of each raw material in Comparative Example 1

[0121]

[0122] Performance testing

[0123] The performance of the aqueous suspending agent prepared in the above examples and comparative examples was tested, and the results are shown in Table 4 below. The suspending rate was tested according to the pesticide suspending rate determination method GB / T14825-2006, the pouring property was tested according to the pesticide pouring property determination method GB / T31737-2015, and the spontaneous dispersion in water was tested according to MT 160 in the CIPAC method.

[0124] Table 4 Performance of the aqueous suspending agent product prepared by compounding mefenpyr-diethyl and butyracarb

[0125]

[0126] Table 4 shows that Comparative Example 1 had poor quality after heat storage. The sample was not tolerant to the high and low temperature range of -15℃ to 65℃. After being stored at -15℃ for 3 days and then transferred to room temperature, the sample thickened into a paste; after being stored at 65℃ for 3 days and then transferred to room temperature, the sample showed crystallization and poor fluidity. Examples 7, 8, 9, and 10 showed a small amount of water separation; while Examples 2, 3, 4, 5, and 6 had good quality both before and after heat storage, and good dispersion stability in different water qualities. Among them, Example 1 showed the best performance in terms of pourability, suspension, and stability. It can be seen that the selection of optimal additives plays a key role in product quality.

[0127] Field trials

[0128] This experiment was conducted in a greenhouse at Shandong Weifang Runfeng Chemical Co., Ltd., Weifang City, Shandong Province. Commercially available propyzamide 480 g / L suspension concentrate, sulfopyrazosulfuron 40% suspension concentrate, and pesticide combinations from Examples 1 and 1 of this invention were selected and mixed into medicated soil according to the designed mass concentration after conversion between field area and pot area. The concentration was calculated at g ai / hm². 2 The pesticide application rate was calculated, with water used as a control. 20 plump, uniformly sized seeds of the grassy weed *Brassica rapa* and the broadleaf weed *Portulaca oleracea* were sown separately and then evenly covered with treated soil. After treatment, the plants were placed in a greenhouse for cultivation, with each treatment repeated three times. The bottom of the pots was watered to ensure the soil was completely moist.

[0129] After application of the pesticide, observe the damage symptoms of brome and purslane regularly. 21 days after application, count the number of surviving brome and purslane plants and the above-ground fresh weight of each treatment. Calculate the control efficacy per plant and the control efficacy per fresh weight of each treatment using the following formula.

[0130] Control efficacy per plant (%) = (Number of weeds in control group - Number of weeds in treatment group) / Number of weeds in control group × 100% Control efficacy per fresh weight (%) = (Fresh weight of weeds in control group - Fresh weight of weeds in treatment group) / Fresh weight of weeds in control group × 100%

[0131] The experimental results are shown in Table 5.

[0132] Table 5. Pharmacological Experiment Data

[0133]

[0134] Table 6. Record of Original Data on Drug Efficacy

[0135]

[0136] The above results indicate that the combination of active components in the pesticide composition provided by this invention reduces the amount of herbicide used, thereby lowering the cost of the pesticide. At the same time, by optimizing the combination of adjuvants such as dispersants and thickeners, the problems of poor product quality after heat storage and intolerance to high and low temperatures are solved, thus improving product stability.

[0137] The above description of the embodiments is only used to help understand the method of the present application and its core idea. It should be noted that, for those skilled in the art, some improvements and modifications can be made to the present application without departing from the principles of the present application, and these improvements and modifications also fall within the protection scope of the claims of the present application.

Claims

1. A suspension concentrate comprising pyroxasulfone and flumioxazin, comprising: active ingredient, dispersant, wetting agent, thickening agent and antifoaming agent; the active ingredient includes pyroxasulfone and flumioxazin; the dispersant consists of a first dispersant, a second dispersant and a third dispersant; the first dispersant is selected from styrene acrylic copolymer sodium salt; the second dispersant is selected from triphenyl ethenyl phenol polyoxyethylene ether sulfate ammonium salt; the third dispersant is selected from maleic rosin block polyether ammonium sulfonate; the wetting agent is selected from one or more of propylene oxide-ethylene oxide block polyether, fatty alcohol polyoxyethylene polyoxypropylene ether.

2. The suspension of metalochlor and propanil according to claim 1, characterized in that, Further comprising: antifreeze and / or preservative.

3. The sulfenyl pyroxyliide and flumioxazin suspension of claim 2, characterized in that, Comprising, by mass content: active ingredient 10%~65%, dispersant 1%~6%, wetting agent 1%~3%, thickening agent 0.2%~2%, antifoaming agent 0.2%~3%, antifreeze 2%~10%, preservative 0.1%~2%, deionized water to 100%; the active ingredient includes pyroxasulfone and flumioxazin; the mass ratio of pyroxasulfone and flumioxazin is 1:(0.01~90).

4. The pyroxasulfone and flumioxazin sulfone-containing suspension concentrate according to claim 1, characterized in that, the mass ratio of the first dispersant, the second dispersant and the third dispersant is (0.1~5):(0.1~5):

1.

5. The suspension of pyroxasulfone and flumioxazin according to any one of claims 1 to 3, characterized in that, the thickening agent is selected from one or more of methyl cellulose, organic bentonite, xanthan gum, common white carbon black and sodium polyacrylate.

6. The sulfenyl pyroxsulam and flumioxazin suspension according to claim 5, characterized in that, the thickening agent consists of a first thickening agent and a second thickening agent; the first thickening agent is selected from common white carbon black; the second thickening agent is selected from xanthan gum.

7. The sulfenyl pyroxsulam and flumioxazin suspension according to claim 6, characterized in that, the mass ratio of the first thickening agent and the second thickening agent is (0.1~0.5):(0.1~0.5).

8. The suspension of pyroxasulfone and flumioxazin according to any one of claims 1 to 3, characterized in that, the antifoaming agent is selected from one or more of polyether antifoaming agent, silicone antifoaming agent and polyether modified polysiloxane antifoaming agent.

9. The sulfentrazone and flumioxazin suspension according to any one of claims 2 to 3, characterized in that, the antifreeze is selected from one or more of urea, potassium chloride, ethylene glycol, propylene glycol, glycerol, polyethylene glycol, sorbitol and sodium chloride; the preservative is selected from one or more of carboxin, formaldehyde, sodium benzoate.

10. The preparation method of the suspension concentrate containing pyroxasulfone and flumioxazin according to any one of claims 1~9, comprising the following steps:

1. Preparation of pulverized slurry First, disperse the dispersant, wetting agent, antifoaming agent and preservative in part of the water, then disperse pyroxasulfone and flumioxazin therein, disperse by high-speed shearing of a shearing machine, pulverize and grind the mixture to a particle size D90 less than 5µm, and obtain a pulverized slurry; 2. Preparation of dispersion medium Disperse the thickening agent and antifreeze in the remaining water to obtain a dispersion medium; 3. Preparation of aqueous suspension concentrate Mix the above pulverized slurry and dispersion medium, disperse by high-speed shearing of a shearing machine, and obtain the suspension concentrate of pyroxasulfone and flumioxazin.

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