Pyriproxyfen microcapsule suspending agent and preparation method thereof

Abstract

The invention discloses a pyriproxyfen microcapsule suspending agent. The pyriproxyfen microcapsule suspending agent is prepared from the following raw materials in percentage by weight: 8 to 12 percent of pyriproxyfen, 1 to 3 percent of isocyanate, 0.1 to 0.5 percent of polyamine and the balance of deionized water. Compared with the traditional dosage form, the pyriproxyfen microcapsule suspending agent has the advantages that the toxicity of aquatic organisms can be obviously reduced; the field dosage can be greatly reduced, the environmental pollution and pesticide residues are effectively reduced, and the production and use cost is reduced; the dosage form of the microcapsule suspending agent accords with the trend of future agricultural environmental protection development; the smell can be reduced, the pesticide effect is improved, and the lasting period is prolonged.

Description

Technical Field

[0001] The invention relates to a pyriproxyfen microcapsule suspension and a preparation method thereof, and relates to A01N, in particular to the field of biocides. Background Art

[0002] Pyriproxyfen is a growth regulator that can disrupt the normal growth of insects. It has a preventive effect on pests in rice and vegetable plants. When used, pyriproxyfen is difficult to work if there is juvenile hormone in the insect body. Therefore, it is generally used in the late larval stage, egg stage and pupal stage. In addition, the use of pyriproxyfen is highly toxic to aquatic organisms in the rice growth environment, affecting the survival of organisms in the aquatic environment. Therefore, it is very important to develop a pesticide formulation that has a high insecticide rate for rice pests and does not affect the survival of other aquatic organisms.

[0003] Chinese invention patent CN201811343547.6 discloses a dinotefuran microcapsule suspension and its preparation method, which uses dinotefuran as the active ingredient, adopts a special solvent combination, and uses a wall material and a curing agent as raw materials to wrap the active ingredient to form a microcapsule suspension. This microcapsule suspension has a high coverage rate and a uniform particle size distribution. It is used for the prevention and control of underground pests, which improves the prevention and control effect and prolongs the duration of the drug. However, it has certain hazards to aquatic organisms. Chinese invention patent CN201510857083.0 discloses a microcapsule containing a macrolide, wherein the active ingredient is protected from UV degradation, has a special release characteristic similar to that of an emulsifiable concentrate, and is effective for a long time. However, the duration of the efficacy is maintained within 10 days, and the duration of the efficacy is short. Summary of the invention

[0004] In order to develop a pesticide preparation with high insecticide rate against rice pests and low toxicity to other aquatic organisms, the first aspect of the present invention provides a pyriproxyfen microcapsule suspension, and the raw materials for preparing the pyriproxyfen microcapsule suspension include, by weight percentage: 8-12% pyriproxyfen, 1-3% isocyanate, 0.1-0.5% polyamine, and deionized water supplemented to 100%.

[0005] As a preferred embodiment, the raw materials for preparing the pyriproxyfen microcapsule suspension include, by weight percentage: 9-11% pyriproxyfen, 1-2% isocyanate, 0.2-0.5% polyamine, and deionized water supplemented to 100%.

[0006] As a preferred embodiment, the raw materials for preparing the pyriproxyfen microcapsule suspension include, by weight percentage: 10% pyriproxyfen, 1% isocyanate, 0.4% polyamine, and deionized water supplemented to 100%.

[0007] As a preferred embodiment, the polyamine is selected from one or a combination of m-cyclohexyl dimethylamine, ethylene diamine, hexamethylene diamine, propylene diamine, and p-phenylenediamine triethylamine.

[0008] As a preferred embodiment, the polyamine is m-cyclohexyl dimethylamine.

[0009] As a preferred embodiment, the isocyanate includes aromatic diisocyanate and aliphatic diisocyanate, and the weight ratio of the aromatic diisocyanate to the aliphatic diisocyanate is (0.2-2):(0.3-0.8).

[0010] As a preferred embodiment, the weight ratio of the aromatic diisocyanate to the aliphatic diisocyanate is (0.5-1):(0.3-0.6).

[0011] As a preferred embodiment, the weight ratio of the aromatic diisocyanate to the aliphatic diisocyanate is 0.6:0.4.

[0012] As a preferred embodiment, the aromatic diisocyanate is diphenylmethane diisocyanate, and the aliphatic diisocyanate is hexamethylene diisocyanate.

[0013] The inventor found in the experimental process that the microcapsule suspension formed by the combination of multiple isocyanates can obtain suspended particles with a small particle size and a small change in particle size after heat storage, and has a good sustained release effect during the application of the drug, and has less harm to the environmental water body. When the existing pyriproxyfen microcapsule suspension is applied to rice, it seriously pollutes the water environment and affects the survival of beneficial organisms in the water body. In this application, a combination of hexamethylene diisocyanate and diphenylmethane diisocyanate is used, and a weight ratio of 0.6:0.4 is used to form microcapsules, which can control the sustained release amount of the drug, and control the amount of the drug to kill pests while not harming beneficial insects, thereby avoiding the problem of water pollution after the application of pesticides. The inventor further found that the combination of hexamethylene diisocyanate and diphenylmethane diisocyanate is matched with meta-cyclohexyl dimethylamine, and the microcapsules formed are flexible and deformable, and have good affinity with the crop surface, have high mechanical strength and toughness, can protect the core material from external impact and damage, and prolong the duration of the drug effect. By adjusting the permeability and degradability of the wall material, the controlled release of pyriproxyfen can be achieved. In addition, hexamethylene diisocyanate also has good light resistance, and the formed drug can resist ultraviolet radiation without degradation.

[0014] As a preferred embodiment, the raw materials for preparing the pyriproxyfen microcapsule suspension further include, by weight percentage: 10-20% solvent, 1-5% emulsifier, 1-5% dispersant, 1-3% antifreeze, 0.1-0.3% thickener, 0.1-0.3% defoamer, and 0.1-0.3% preservative.

[0015] As a preferred embodiment, the raw materials for preparing the pyriproxyfen microcapsule suspension further include, by weight percentage: 15% solvent, 4% emulsifier, 2% dispersant, 2% antifreeze, 0.1% thickener, 0.1% defoamer, and 0.1% preservative.

[0016] As a preferred embodiment, the emulsifier is selected from one or a combination of sodium dodecyl sulfate, calcium dodecyl sulfonate, alkylphenol polyoxyethylene ether, fatty alcohol polyoxyethylene ether, nonylphenol polyoxyethylene ether phosphate, alkylnaphthalene formaldehyde condensate sodium sulfonate, and triphenylethylphenol polyoxyethylene ether.

[0017] As a preferred embodiment, the emulsifier is a combination of fatty alcohol polyoxyethylene ether AEO-10 ​​and triphenyl phenol polyoxyethylene ether.

[0018] As a preferred embodiment, the weight ratio of the fatty alcohol polyoxyethylene ether AEO-10 ​​and triphenyl phenol polyoxyethylene ether is (1-3): (1-3).

[0019] As a preferred embodiment, the weight ratio of the fatty alcohol polyoxyethylene ether AEO-10 ​​and triphenyl phenol polyoxyethylene ether is 1:1.

[0020] As a preferred embodiment, the dispersant is selected from one or a combination of naphthalenesulfonate formaldehyde condensate, tristyrylphenol polyoxyethylene ether sulfate ammonium salt, fatty alcohol polyoxyethylene ether sodium sulfate, fatty alcohol polyoxyethylene ether phosphate, alkylphenol polyoxyethylene ether sodium sulfate, alkylphenol polyoxyethylene ether phosphate, EO-PO block copolymer, and polycarboxylate.

[0021] As a preferred embodiment, the dispersant is a polycarboxylate.

[0022] As a preferred embodiment, the thickener is selected from one or a combination of xanthan gum, cellulose ether, cellulose ether derivatives, polyethylene glycol, polyvinyl alcohol, magnesium aluminum silicate, bentonite, kaolin, and diatomaceous earth.

[0023] As a preferred embodiment, the thickener is xanthan gum.

[0024] As a preferred embodiment, the solvent is selected from one or a combination of aromatic hydrocarbons, xylene cyclohexanone mineral oil, methylated vegetable oil, and propylene glycol methyl ether.

[0025] As a preferred embodiment, the solvent is aromatic hydrocarbon S-200.

[0026] As a preferred embodiment, the antifreeze agent is selected from ethylene glycol, propylene glycol, glycerol or a combination of several thereof.

[0027] As a preferred embodiment, the antifreeze agent is glycerol.

[0028] As a preferred embodiment, the defoaming agent is a polysiloxane defoaming agent.

[0029] As a preferred embodiment, the preservative is isothiazolinone.

[0030] As a preferred embodiment, the D90 particle size of the microcapsules in the microcapsule suspension is 1-50 μm.

[0031] Pyriproxyfen Ecological Effects: Salmon LC 50 (96h)>0.325mg / L, Daphnia EC 50 (48h) 0.4mg / L, seaweed EC 50 (48h) 0.4mg / L. Highly toxic to aquatic organisms.

[0032] Compared with traditional pesticide formulations, microcapsule suspensions have many advantages, which can reduce the impact of rainfall on the effect of pesticides to a certain extent and enhance stability. In addition, the microcapsule suspension of the present invention can effectively reduce the volatility of chemical active ingredients and reduce the loss of pesticides caused by rainfall. At the same time, the microcapsule wall material has a certain protective effect on the active ingredients, which can prevent them from being directly exposed to wind and rain, thereby maintaining the stability of the efficacy. Resistant to rain erosion, the microcapsules can adhere well to the surface of plant leaves and have a strong effect of resisting rain erosion. After rainfall, the microcapsules can still remain on the leaves and continue to play a preventive effect. The microcapsules of the present invention have a controlled release function, which can slowly release the active ingredients, so that the pesticides remain active on crops for a long time, thereby reducing the reduction in efficacy caused by rainfall.

[0033] The second aspect of the present invention provides a method for preparing a pyriproxyfen microcapsule suspension, comprising the following steps:

[0034] S1: dissolving pyriproxyfen in a solvent, adding isocyanate and stirring to obtain an oil phase;

[0035] S2: adding an emulsifier to deionized water, stirring to obtain a water phase, and then adding an oil phase while shearing to form an oil-in-water emulsion;

[0036] S3 then adds polyamine to the oil-in-water emulsion while stirring, adjusts the temperature to solidify the capsule wall, and forms a capsule wall coated with pyriproxyfen after reaction;

[0037] S4 then adds dispersant, antifreeze agent, thickener, preservative and defoamer and stirs evenly to obtain the product.

[0038] As a preferred embodiment, the shear rate in step S2 is 1000-20000 rpm.

[0039] As a preferred embodiment, in step S3, the stirring rate is 100-1000 rpm, the reaction temperature is 30-50° C., the reaction time is 2-3 h, and the pH value is 5.0-7.0.

[0040] Compared with the prior art, the present invention has the following beneficial effects:

[0041] (1) The pyriproxyfen microcapsule suspension of the present invention adopts a combination of hexamethylene diisocyanate and diphenylmethane diisocyanate. The particle size of the microcapsules in the formed microcapsule suspension is small, and the particle size does not change much after heat storage, and the heat storage stability is high.

[0042] (2) In the pyriproxyfen microcapsule suspension of the present invention, hexamethylene diisocyanate and diphenylmethane diisocyanate are formed into microcapsules in a weight ratio of 0.6:0.4, which can control the sustained release amount of the drug, have a good sustained release effect during the application process, and have less harm to the environment and water bodies.

[0043] (3) The pyriproxyfen microcapsule suspension of the present invention comprises a combination of hexamethylene diisocyanate and diphenylmethane diisocyanate and m-cyclohexylene dimethylamine. The microcapsules formed are flexible and deformable, have good affinity with the surface of crops, and have high mechanical strength and toughness.

[0044] (4) The pyriproxyfen microcapsule suspension of the present invention has good light resistance. The formed drug can resist ultraviolet radiation without degradation, has high storage stability and slow release, reduces drug damage, and is safe for crops.

[0045] (5) The pyriproxyfen microcapsule suspension of the present invention can protect the core material from external impact and damage, and prolong the duration of drug efficacy. By adjusting the permeability and degradability of the wall material, the controlled release of pyriproxyfen can be achieved.

[0046] (6) Compared with the traditional dosage form, the pyriproxyfen microcapsule suspension of the present invention can significantly reduce the toxicity to aquatic organisms; and can significantly reduce the amount of pesticides used in the field, effectively reduce environmental pollution and pesticide residues, and reduce production and use costs; the microcapsule suspension dosage form of the present invention is in line with the future trend of agricultural environmental protection development; it can reduce odor, improve efficacy, and prolong the duration of effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1-5 The following are photos of the microcapsule suspensions of Examples 1-5 under a microscope. DETAILED DESCRIPTION

[0048] Example 1

[0049] A pyriproxyfen microcapsule suspension, wherein the raw materials for preparing the pyriproxyfen microcapsule suspension include, by weight percentage, 10% pyriproxyfen, 2% isocyanate, 0.4% polyamine, 15% solvent, 4% emulsifier, 5% dispersant, 2% antifreeze, 0.1% thickener, 0.1% defoamer, 0.1% preservative, and deionized water supplemented to 100%.

[0050] The isocyanate is a combination of hexamethylene diisocyanate and diphenylmethane diisocyanate, with a weight ratio of 0.3:1.7. The polyamine is m-cyclohexyl dimethylamine. The solvent is aromatic hydrocarbon S-200. The emulsifier is a combination of AEO-10 ​​and triphenyl phenol polyoxyethylene ether 33#, with a weight ratio of 2:2. AEO-10 ​​is purchased from Nanjing Taihua, and triphenyl phenol polyoxyethylene ether 33# is purchased from Jiangsu Kaiyuan. The dispersant is polycarboxylate dispersant 4913, purchased from Heda. The antifreeze is glycerol. The thickener is xanthan gum. The defoamer is silicone defoamer SAG-1522, purchased from Nanjing Jierun. The preservative is isothiazolinone.

[0051] A method for preparing a pyriproxyfen microcapsule suspension comprises the following steps:

[0052] S1: dissolving pyriproxyfen in a solvent, adding isocyanate and stirring to obtain an oil phase;

[0053] S2: adding an emulsifier to deionized water, stirring to obtain a water phase, and then adding an oil phase while shearing to form an oil-in-water emulsion;

[0054] S3 then adds polyamine to the oil-in-water emulsion while stirring, adjusts the temperature to solidify the capsule wall, and forms a capsule wall coated with pyriproxyfen after reaction;

[0055] S4 then adds dispersant, antifreeze agent, thickener, preservative and defoamer and stirs evenly to obtain the product.

[0056] The shear rate in step S2 is 10000 rpm.

[0057] In step S3, the stirring rate is 300 rpm, the reaction temperature is 50° C., the reaction time is 2 h, and the pH value is 6.0.

[0058] Example 2

[0059] A pyriproxyfen microcapsule suspension, wherein the raw materials for preparing the pyriproxyfen microcapsule suspension include, by weight percentage, 10% pyriproxyfen, 2% isocyanate, 0.4% polyamine, 15% solvent, 4% emulsifier, 5% dispersant, 2% antifreeze, 0.1% thickener, 0.1% defoamer, 0.1% preservative, and deionized water supplemented to 100%.

[0060] The isocyanate is a combination of hexamethylene diisocyanate and diphenylmethane diisocyanate, with a weight ratio of 0.6:1.4. The polyamine is m-cyclohexyl dimethylamine. The solvent is aromatic hydrocarbon S-200. The emulsifier is a combination of AEO-10 ​​and triphenyl phenol polyoxyethylene ether 33#, with a weight ratio of 2:2. AEO-10 ​​is purchased from Nanjing Taihua, and triphenyl phenol polyoxyethylene ether 33# is purchased from Jiangsu Kaiyuan. The dispersant is polycarboxylate dispersant 4913, purchased from Heda. The antifreeze is glycerol. The thickener is xanthan gum. The defoamer is silicone defoamer SAG-1522, purchased from Nanjing Jierun. The preservative is isothiazolinone.

[0061] The preparation method of the pyriproxyfen microcapsule suspension is the same as that in Example 1.

[0062] Example 3

[0063] A pyriproxyfen microcapsule suspension. The raw materials for preparing the pyriproxyfen microcapsule suspension include, by weight percentage, 10% pyriproxyfen, 1% isocyanate, 0.2% polyamine, 15% solvent, 4% emulsifier, 5% dispersant, 2% antifreeze, 0.1% thickener, 0.1% defoamer, 0.1% preservative, and deionized water supplemented to 100%.

[0064] The isocyanate is a combination of hexamethylene diisocyanate and diphenylmethane diisocyanate, with a weight ratio of 0.4:0.6. The polyamine is m-cyclohexyl dimethylamine. The solvent is aromatic hydrocarbon S-200. The emulsifier is a combination of AEO-10 ​​and triphenyl phenol polyoxyethylene ether 33#, with a weight ratio of 2:2. AEO-10 ​​is purchased from Nanjing Taihua, and triphenyl phenol polyoxyethylene ether 33# is purchased from Jiangsu Kaiyuan. The dispersant is polycarboxylate dispersant 4913, purchased from Heda. The antifreeze is glycerol. The thickener is xanthan gum. The defoamer is silicone defoamer SAG-1522, purchased from Nanjing Jierun. The preservative is isothiazolinone.

[0065] The preparation method of the pyriproxyfen microcapsule suspension is the same as that in Example 1.

[0066] Example 4

[0067] A pyriproxyfen microcapsule suspension. The raw materials for preparing the pyriproxyfen microcapsule suspension include, by weight percentage, 10% pyriproxyfen, 1% isocyanate, 0.2% polyamine, 15% solvent, 4% emulsifier, 5% dispersant, 2% antifreeze, 0.1% thickener, 0.1% defoamer, 0.1% preservative, and deionized water supplemented to 100%.

[0068] The isocyanate is a combination of hexamethylene diisocyanate and diphenylmethane diisocyanate, with a weight ratio of 0.5:0.5. The polyamine is m-cyclohexyl dimethylamine. The solvent is aromatic hydrocarbon S-200. The emulsifier is a combination of AEO-10 ​​and triphenyl phenol polyoxyethylene ether 33#, with a weight ratio of 2:2. AEO-10 ​​is purchased from Nanjing Taihua, and triphenyl phenol polyoxyethylene ether 33# is purchased from Jiangsu Kaiyuan. The dispersant is polycarboxylate dispersant 4913, purchased from Heda. The antifreeze is propylene glycol. The thickener is xanthan gum. The defoamer is silicone defoamer SAG-1522, purchased from Nanjing Jierun. The preservative is isothiazolinone.

[0069] The preparation method of the pyriproxyfen microcapsule suspension is the same as that in Example 1.

[0070] Example 5

[0071] A pyriproxyfen microcapsule suspension. The raw materials for preparing the pyriproxyfen microcapsule suspension include, by weight percentage, 10% pyriproxyfen, 1% isocyanate, 0.4% polyamine, 15% solvent, 4% emulsifier, 5% dispersant, 2% antifreeze, 0.1% thickener, 0.1% defoamer, 0.1% preservative, and deionized water supplemented to 100%.

[0072] The isocyanate is a combination of hexamethylene diisocyanate and diphenylmethane diisocyanate, with a weight ratio of 0.6:0.4. The polyamine is m-cyclohexyl dimethylamine. The solvent is aromatic hydrocarbon S-200. The emulsifier is a combination of AEO-10 ​​and triphenyl phenol polyoxyethylene ether 33#, with a weight ratio of 2:2. AEO-10 ​​is purchased from Nanjing Taihua, and triphenyl phenol polyoxyethylene ether 33# is purchased from Jiangsu Kaiyuan. The dispersant is polycarboxylate dispersant 4913, purchased from Heda. The antifreeze is glycerol. The thickener is xanthan gum. The defoamer is silicone defoamer SAG-1522, purchased from Nanjing Jierun. The preservative is isothiazolinone.

[0073] The preparation method of the pyriproxyfen microcapsule suspension is the same as that in Example 1.

[0074] Performance Testing one,

[0076] 1. pH value determination method: GB / T 1601-1993

[0077] 2. Suspension rate test method: GB / T14825-2006

[0078] 3. Spontaneous dispersion test method: HG / T 2467.13-2003

[0079] 4. Test method for persistent foaming: GB / T 28137-2011

[0080] 5. Free component content test, release rate test: Use acetone to break the capsule and fully disperse and dissolve, use n-hexane tetrahydrofuran as mobile phase, use stainless steel column with silica gel as filler and UV detector, and separate the pyriproxyfen in the sample by normal phase high performance liquid chromatography at a wavelength of 230nm, and quantify by external standard method. The free pyriproxyfen content and release rate are determined by rotating on a horizontal rotating device for a certain period of time, extracting the free and released pyriproxyfen with n-hexane and release medium solution respectively, and determining them by the same method.

[0081] Release medium solution: Add 100 mL of ethanol to a 1000 mL volumetric flask, dilute to volume with n-hexane, and shake well. Preparation of standard solution: Weigh 0.05 g (accurate to 0.0001 g) of pyriproxyfen standard into a 50 mL volumetric flask, add 40 mL of mobile phase, ultrasonically vibrate for 10 min to dissolve it, cool to room temperature, dilute to volume with mobile phase, and shake well.

[0082] Determination of free pyriproxyfen mass fraction:

[0083] Preparation of sample solution: weigh 0.1g of sample (accurate to 0.0001g) into a dry 150mL glass bottle, add 6mL of water, and shake to disperse the sample completely. Then add 100mL of n-hexane, cover the bottle and place it on a horizontal rotating device, set the bottle speed to (70±10)r / min, and start timing at the same time. After 5min±10s, remove the bottle and place it vertically on a horizontal table, immediately transfer 1mL of the upper n-hexane to the injection bottle, and cover the lid.

[0084] Release rate determination:

[0085] Preparation of sample solution: weigh 0.1g of sample (accurate to 0.0001g) into a dry 150mL glass bottle, add 6mL of water, and shake to disperse the sample completely. Then add 100mL of release medium solution, cover the bottle with a lid, and place it on a horizontal rotating device. Set the bottle to rotate at (70±10)r / min, and start timing at the same time. After 15min±10s, remove the bottle, place it vertically on a horizontal table, and immediately transfer 1mL of the upper release medium solution to the injection bottle, and cover the lid. If the release amount at 30min and 180min needs to be measured, add 1mL of release medium to the glass bottle immediately after taking out the medium solution, and put the glass bottle back on the device to continue rolling, and perform the same operation at 30min and 180min.

[0086] calculate

[0087] The peak areas of pyriproxyfen in the two sample solutions and the two standard sample solutions before and after the sample were averaged. The mass fraction of pyriproxyfen in the sample was calculated according to formula (1), the mass fraction of free high-efficiency pyriproxyfen was calculated according to formula (2), and the release rate was calculated according to formula (3).

[0088]

[0089]

[0090] ω 1 ——The mass fraction of pyriproxyfen in the sample, in percentage (%);

[0091] A 2 ——The average value of the pyriproxyfen peak area in the sample solution;

[0092] m 1 ——Numerical value of standard sample mass, in grams (g);

[0093] ω——mass fraction of pyriproxyfen in standard sample, in percentage (%);

[0094] A 1 ——The average value of the peak area of ​​pyriproxyfen in the standard solution;

[0095] m 2 ——Numerical value of the sample mass, in grams (g);

[0096] ω 2 ——The mass fraction of free pyriproxyfen in the sample, in percentage (%);

[0097] A 3 ——The average value of the pyriproxyfen peak area in the n-hexane layer;

[0098] m 3 ——The mass fraction of free pyriproxyfen is the value of the mass of the sample to be measured, in grams (g); 3 ——Release rate, in percentage (%);

[0099] A 4 ——The average value of the pyriproxyfen peak area in the release medium solution layer;

[0100] m 4 ——The value of the mass of the release rate test sample, in grams (g).

[0101] The test results are shown in Table 1.

[0102] Table 1

[0103]

[0104] two,

[0106] Particle size determination: The room temperature particle size and hot storage particle size of the pyriproxyfen microcapsule suspension in Examples 1-5 were determined by laser particle size analyzer. The test results are shown in Table 2.

[0107] Table 2

[0108] Example <![CDATA[Normal temperature particle size (D 90 )(μm)]]> <![CDATA[Thermal reservoir particle size (D 90 )(μm)]]> Example 1 5.2 7.2 Example 2 5.4 7.7 Example 3 4.6 6.2 Example 4 4.2 7.4 Example 5 3.4 4.1

[0109] 3. The acute toxicity test on zebrafish (Brachydaniorerio) was carried out in accordance with the provisions of Part 12: Acute Toxicity Test for Fish of GB / T31270.12-2014 "Test Guidelines for Environmental Safety Assessment of Chemical Pesticides" for 10% pyriproxyfen CS (microcapsule suspension), 10% pyriproxyfen·high-efficiency cypermethrin ME (microemulsion), 100 g / L pyriproxyfen EC (emulsifiable concentrate), 20% emamectin chlorpyrifos·pyriproxyfen SC (suspension concentrate), and 30% pyriproxyfen·chlorfenapyr SC (suspension concentrate).

[0110] The test results are shown in Table 3: The static method was used for formal testing, and 7 theoretical concentrations were set: 0.120mgai / L (Cl), 0.170mgai / L (C2), 0.241mgai / L (C3), 0.342mga.i. / L (C4), 0.486mga.i / L (C5), 0.690mgai. / L (C6) and 0.980mgai. / L (C7), 7 fish for each concentration, one group of parallel, and a blank control group. The test period was 96h. During the test, the pH of the control group and the test group solution was measured between 7.17 and 8.02, the dissolved oxygen content was maintained between 75.0% and 95.4% of the air saturation value, and the temperature of the test solution was between 22.1℃ and 22.6℃. The pH of the test water is 6.0-8.5, the dissolved oxygen content is higher than 60% of the air saturation value, and the hardness is 40mg / L-250mg / L (calculated as calcium carbonate).

[0111] Table 3

[0112]

[0113]

[0114] According to the toxicity grade evaluation standards specified in Part 12: Acute Toxicity Test for Fish of GB / T 31270.12-2014 "Test Guidelines for Environmental Safety Assessment of Chemical Pesticides", under the test conditions of this laboratory, for zebrafish, 10% pyriproxyfen microcapsule CS is classified as "low toxicity", 100g / L pyriproxyfen EC is classified as "moderately poisonous", 30% pyriproxyfen·chlorfenapyr SC is classified as "extremely toxic", 20% emamectin benzoate·pyriproxyfen SC is classified as "poisonous", and 10% pyriproxyfen·cypermethrin ME is classified as "extremely toxic". Four,

[0116] 10% pyriproxyfen CS, 10% pyriproxyfen·cypermethrin ME, 100g / L pyriproxyfen EC, 20% emamectin chlorpyrifos·pyriproxyfen SC, 30% pyriproxyfen·chlorfenapyr SC are in accordance with GB / T 31270.13-2014 "Test Guidelines for Environmental Safety Assessment of Chemical Pesticides" Part 13: Acute activity inhibition test for Daphnia, the acute activity inhibition test for Daphnia magna Straus.

[0117] The test results are shown in Table 4: The static method was used for formal experiments, and 7 concentrations were set: 0.000200 mga.i. / L (C1), 0.000260 mga.i. / L (C2); 0.000338 mga.i. / L (C3), 0.000439 mga.i. / L (C4), 0.000571 mga.i. / L (C5), 0.000742 mga.i. / L (C6) and 0.000965 mga.i. / L (C7). A blank control group was also set up. Both the experimental group and the control group were set up with 4 parallels, with 5 Daphnia in each parallel, and the test period was 48 hours.

[0118] During the test, the test temperature was maintained between 20.0℃ and 20.5℃, the pH value was maintained between 7.6 and 8.2, and the dissolved oxygen content was maintained between 7.75mg / L and 8.28mg / L. The pH of the test water was 6.0 to 9.0, the dissolved oxygen content was not less than 3.0mg / L, and the hardness was 140mg / L to 250mg / L (calculated as calcium carbonate).

[0119] Table 4

[0120] LC50(48h) 100g / L Pyriproxyfen EC 0.100mgga.i / L 30% Pyriproxyfen-Cyclofenac SC 0.00466aimg / L 20% Retinyl pyriproxyfen SC 0.000980aimg / L 10% Pyriproxyfen·Cypermethrin ME 0.000255aimg / L 10% Pyriproxyfen CS >100mg / L

[0121] According to the toxicity grade evaluation standards specified in Part 13 of GB / T 31270.13-2014 "Test Guidelines for Environmental Safety Assessment of Chemical Pesticides": Acute Activity Inhibition Test for Daphnia, under the test conditions of this laboratory, for Daphnia magna, 10% pyriproxyfen microcapsule CS is classified as "low toxicity", 100g / L pyriproxyfen EC is classified as "highly toxic", 30% pyriproxyfen·chlorfenapyr SC is classified as "highly toxic", 20% emamectin benzoate·pyriproxyfen SC is classified as "highly toxic", and 10% pyriproxyfen·cypermethrin ME is classified as "highly toxic".

[0122] 10% pyriproxyfen CS significantly reduced the toxicity of pyriproxyfen to aquatic organisms. five,

[0124] The test agent was 10% pyriproxyfen microcapsule suspension, and the control agents were 15.5% emamectin benzoate·chlorantraniliprole suspension, 33% chlorantraniliprole·indoxime suspension, and 25% methoxyfenoxam·indoxacarb suspension. The spraying method was adopted as usual.

[0125] The experimental site was selected as the Songfeng Vegetable and Fruit Professional Cooperative located in Songjiang District, Shanghai, which is a rice field.

[0126] The pesticide was applied at the peak period of the occurrence of the Chilo suppressalis, and a manual sprayer was used to spray evenly. The base number of rice insects was investigated before spraying, and the number of remaining live insects was sampled and investigated once 3 days, 7 days, and 15 days after the application of the pesticide. Ten points were selected from each plot, and 2 clusters were checked at each point, and a total of 20 clusters were checked in each plot. The insect population reduction rate of each plot was calculated based on the base number before the application of the pesticide, and the control effect was calculated based on the insect population reduction rate of the control area, and the control effect was compared for significant differences.

[0127] Calculation method of drug efficacy:

[0128] A. Insect population reduction rate (%) = (insect population before application - insect population after application) / insect population before application × 100; B. Control effect (%) = (insect population reduction rate in treatment area - insect population reduction rate in blank control area) / (100% - insect population reduction rate in blank control area) × 100%. The test results are shown in Table 5.

[0129] Table 5

[0130]

[0131]

[0132] The results of the field plot efficacy test of 10% pyriproxyfen microcapsule suspension against the striped stem borer showed that, when 1000 times and 1500 times of 10% pyriproxyfen microcapsule suspension were evenly sprayed once, the control effects on the striped stem borer reached 98.06% and 97.76%, 96.74% and 96.43%, 97.48% and 97.31% at 3, 7 and 15 days after the spraying, respectively, which were significantly better than the control agents 15.5% emamectin benzoate·chlorfenapyr suspension, 33% chlorfenapyr·indoxime suspension, and 25% methoxyfenozide·indoxacarb suspension.

[0133] 6. The microcapsule suspension prepared in Examples 1-5 was observed under a microscope. Figure 1-5 .

[0134] It can be seen from the picture that the cyst wall and cyst core can be clearly seen. It is obviously wrapped by the cyst wall and its shape is spherical.

Claims

1. A pyriproxyfen microcapsule suspension, characterized in that: The raw materials for preparing the pyriproxyfen microcapsule suspension include, by weight percentage: 8-12% pyriproxyfen, 1-3% isocyanate, 0.1-0.5% polyamine, and deionized water supplemented to 100%.

2. The pyriproxyfen microcapsule suspension according to claim 1, characterized in that: The polyamine is selected from one or a combination of m-cyclohexyl dimethylamine, ethylene diamine, hexamethylene diamine, propylene diamine, and p-phenylenediamine triethylamine.

3. The pyriproxyfen microcapsule suspension according to claim 1, characterized in that: The isocyanate comprises aromatic diisocyanate and aliphatic diisocyanate, and the weight ratio of the aromatic diisocyanate to the aliphatic diisocyanate is (0.2-2):(0.3-0.8).

4. The pyriproxyfen microcapsule suspension according to claim 1, characterized in that: The raw materials for preparing the pyriproxyfen microcapsule suspension include, by weight percentage: 10-20% solvent, 1-5% emulsifier, 1-5% dispersant, 1-3% antifreeze, 0.1-0.3% thickener, 0.1-0.3% defoamer, and 0.1-0.3% preservative.

5. The pyriproxyfen microcapsule suspension according to claim 4, characterized in that: The emulsifier is selected from one or a combination of sodium dodecyl sulfate, calcium dodecyl sulfonate, alkylphenol polyoxyethylene ether, fatty alcohol polyoxyethylene ether, nonylphenol polyoxyethylene ether phosphate, alkylnaphthalene formaldehyde condensate sodium sulfonate, and triphenylethylphenol polyoxyethylene ether.

6. The pyriproxyfen microcapsule suspension according to claim 4, characterized in that: The dispersant is selected from naphthalenesulfonate formaldehyde condensate, tristyrylphenol polyoxyethylene ether sulfate ammonium salt, fatty alcohol polyoxyethylene ether sodium sulfate, fatty alcohol polyoxyethylene ether phosphate, alkylphenol polyoxyethylene ether sodium sulfate, alkylphenol polyoxyethylene ether phosphate, polycarboxylate, EO-PO block copolymer or a combination of the two.

7. The pyriproxyfen microcapsule suspension according to claim 4, characterized in that: The thickener is selected from one or a combination of xanthan gum, cellulose ether, cellulose ether derivatives, polyethylene glycol, polyvinyl alcohol, magnesium aluminum silicate, bentonite, kaolin, and diatomaceous earth.

8. The pyriproxyfen microcapsule suspension according to claim 4, characterized in that: The solvent is selected from one or a combination of aromatic hydrocarbons, xylene cyclohexanone mineral oil, methylated vegetable oil, and propylene glycol methyl ether.

9. The pyriproxyfen microcapsule suspension according to claim 1, characterized in that: The D90 particle size of the microcapsules in the microcapsule suspension is 1-50 μm.

10. A method for preparing the pyriproxyfen microcapsule suspension according to any one of claims 4 to 9, characterized in that: The following steps are involved: S1: dissolving pyriproxyfen in a solvent, adding isocyanate and stirring to obtain an oil phase; S2: adding an emulsifier to deionized water, stirring to obtain a water phase, and then adding an oil phase while shearing to form an oil-in-water emulsion; S3 then adds polyamine to the oil-in-water emulsion while stirring, adjusts the temperature to solidify the capsule wall, and forms a capsule wall coated with pyriproxyfen after reaction; S4 then adds dispersant, antifreeze agent, thickener, preservative and defoamer and stirs evenly to obtain the product.

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