Pesticide composition containing carbendazim and preparation method thereof

Abstract

The invention discloses a carbendazim-containing pesticide composition and a preparation method thereof, and relates to the technical field of pesticides, the carbendazim-containing pesticide composition comprises the following components by weight: 15-20 parts of carbendazim, 10-15 parts of modified beta-cyclodextrin, 8-12 parts of modified polyethylene glycol, 2-4 parts of modified carbon nanotubes, 2-4 parts of an auxiliary agent, and 50-65 parts of deionized water; wherein the surface of the modified beta-cyclodextrin is connected with carboxymethyl; the surface of the modified polyethylene glycol is connected with a gallate bond; the surface of the modified carbon nanotube is coated with zinc oxide quantum dots; a hydrophobic cavity is formed in the modified beta-cyclodextrin and can be connected with a benzene ring in the carbendazim, so that the carbendazim is coated with the hydrophobic cavity, the drug loading effect is achieved, a hydrogen bond network structure is formed through carboxyl and amino in the carbendazim, and the drug loading stability is improved; the modified polyethylene glycol can achieve the purpose of drug release only aiming at a fungus infection part, the drug effect is reserved at a part without fungus infection, and the controllability of the slow release effect is achieved.

Description

Technical Field

[0001] This invention relates to the field of pesticide technology, specifically to a pesticide composition containing carbendazim and its preparation method. Background Technology

[0002] Carbendazim, a broad-spectrum benzimidazole fungicide, is widely used in the prevention and control of fungal diseases in fruit trees, vegetables, and field crops by inhibiting the polymerization of β-tubulin in pathogens and interfering with mitosis.

[0003] In practical applications, the benzimidazole ring of carbendazim is easily degraded under ultraviolet light, resulting in a short field residual effect, requiring frequent application, increasing costs and the risk of resistance. Furthermore, carbendazim's water solubility is only 8 mg / L (25℃), and traditional formulations rely on large amounts of organic solvents or adjuvants, easily causing phytotoxicity and environmental pollution. Long-term single-use can lead to β-tubulin mutations in various pathogens, and conventional carbendazim formulations have reduced EC50 resistance to resistant strains. 50 When the value increases by 10-100 times, the preventive effect decreases significantly.

[0004] In existing technologies, β-cyclodextrin can be used to encapsulate carbendazim to improve its photostability in order to enhance its efficacy. However, unmodified cyclodextrin has a low loading rate, typically below 70%, and the encapsulation compound has poor permeability in the leaf wax layer, failing to achieve efficient delivery. While using adjuvants (such as organosilicon synergists) can temporarily improve efficacy, it cannot address the fundamental problem of resistant strains and may increase toxicity to non-target organisms, affecting the sustained-release and fungicidal effects of carbendazim. Summary of the Invention

[0005] The purpose of this invention is to provide a high-flatness PU adhesive protective film and its preparation method, thereby solving the following technical problems:

[0006] How to improve the sustained-release effect and fungicidal effect of pesticide compositions containing carbendazim.

[0007] The objective of this invention can be achieved through the following technical solutions:

[0008] In a first aspect, the present invention discloses a pesticide composition containing carbendazim, comprising the following components by weight: 15-20 parts of carbendazim, 10-15 parts of modified β-cyclodextrin, 8-12 parts of modified polyethylene glycol, 2-4 parts of modified carbon nanotubes, 2-4 parts of adjuvants, and 50-65 parts of deionized water.

[0009] The modified β-cyclodextrin has carboxymethyl groups attached to its surface; the modified polyethylene glycol has gallate bonds attached to its surface; and the modified carbon nanotubes are coated with zinc oxide quantum dots.

[0010] Preferably, the pesticide composition containing carbendazim comprises the following components by weight: 18 parts carbendazim, 12 parts modified β-cyclodextrin, 10 parts modified polyethylene glycol, 3 parts modified carbon nanotubes, 3 parts adjuvants, and 60 parts deionized water.

[0011] Furthermore, the preparation method of the modified β-cyclodextrin includes the following steps:

[0012] Step A1: Dissolve β-cyclodextrin in NaOH solution and stir at 60℃ for 1 hour to obtain a mixture; during this process, the hydroxyl groups in β-cyclodextrin are deprotonated in NaOH solution, generating O - This enhances its nucleophilicity, providing an active site for subsequent carboxymethylation.

[0013] Step A2: Add chloroacetic acid dropwise to the mixture and stir until homogeneous. Then adjust the pH to 12-13 and react at 70℃ for 6 hours to obtain the reaction solution. During this process, the Cl- in the chloroacetic acid... - O in β-cyclodextrin - The substitution forms -O-CH2-COOH, achieving carboxymethylation.

[0014] Step A3: Adjust the pH of the reaction solution to 6.5, add anhydrous ethanol, centrifuge, and vacuum dry the precipitate to obtain modified β-cyclodextrin.

[0015] Preferably, in step A1, the NaOH solution has a mass fraction of 10%.

[0016] Preferably, in step A1, the ratio of β-cyclodextrin to NaOH solution is 1g:10mL.

[0017] Preferably, in step A2, the weight ratio of the chloroacetic acid to the β-cyclodextrin in step A1 is 1:2.

[0018] Preferably, in step A2, the pH is adjusted to 12-13 by adding NaOH solution dropwise.

[0019] Preferably, in step A3, the pH is adjusted to 6.5 by adding hydrochloric acid solution dropwise.

[0020] Preferably, in step A3, the volume of anhydrous ethanol added is 10% of the reaction solution.

[0021] Based on this, a preferred method for preparing modified β-cyclodextrin is obtained, comprising the following steps:

[0022] Step a1: In a stirred tank, dissolve β-cyclodextrin in a 10% NaOH solution at a ratio of 1g:10mL, and stir at 200rpm for 1h at 60℃ to obtain a mixture;

[0023] Step a2: Add chloroacetic acid (0.5 times the weight of β-cyclodextrin) dropwise to the mixture and stir until homogeneous. Then add 30% NaOH solution to adjust the pH to 12.5. React at 70°C for 6 hours to obtain the reaction solution.

[0024] Step a3: Add 30% hydrochloric acid dropwise to the reaction solution to adjust the pH of the reaction solution to 6.5. Add anhydrous ethanol in an amount equal to 0.1 times the volume of the reaction solution and stir well. Then transfer the mixture to a centrifuge and centrifuge at 8000 rpm for 10 min. Transfer the precipitate to a vacuum drying oven and vacuum dry at 80℃ for 2 h to obtain modified β-cyclodextrin.

[0025] Furthermore, the preparation method of the modified polyethylene glycol includes the following steps:

[0026] Step B1: Dissolve chitosan in acetic acid solution and stir until homogeneous. Then add 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and N-hydroxysuccinimide (NHS) and stir for 30 minutes to obtain an activated solution.

[0027] Step B2: Add propyl gallate to the activation solution and react at 40°C for 12 hours. Then add polyethylene glycol diglycidyl ether and react at 60°C for 6 hours to obtain a polymer precursor solution. During this process, EDC activates the carboxyl groups in propyl gallate, converting them into highly reactive esters. Under the linkage of NHS, these highly reactive esters are converted into more stable esters, thereby forming amide bonds with the amino groups in chitosan, while the phenolic hydroxyl groups in chitosan are fully preserved. The epoxy groups in polyethylene glycol diglycidyl ether undergo ring-opening reactions with the remaining amino groups in chitosan to form hydrophilic segments.

[0028] Step B3: The polymer precursor solution is dialyzed and freeze-dried sequentially to remove unreacted small molecules. After pulverization, modified polyethylene glycol, which appears as white flocculent material, is obtained.

[0029] Preferably, in step B1, the acetic acid solution has a mass fraction of 20%.

[0030] Preferably, in step B1, the ratio of chitosan to acetic acid solution is 1g:20mL.

[0031] Preferably, in step B1, the weight ratio of chitosan, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide is 10:2:1.2.

[0032] Preferably, in step B2, the weight ratio of propyl gallate, polyethylene glycol diglycidyl ether, and chitosan in step B1 is 5:8:10.

[0033] Based on this, a preferred method for preparing modified polyethylene glycol is obtained, comprising the following steps:

[0034] Step b1: In the reaction vessel, dissolve chitosan in a 20% acetic acid solution at a ratio of 1g:20mL and stir until homogeneous. Then add EDC (0.2 times the weight of chitosan) and NHS (0.12 times the weight of chitosan) and stir at 200rpm for 30min to obtain the activated solution.

[0035] Step b2: Add propyl gallate (0.5 times the weight of chitosan) to the activation solution and react at 40°C for 12 hours. Then add polyethylene glycol diglycidyl ether (0.8 times the weight of chitosan) and react at 60°C for 6 hours to obtain a polymer precursor solution.

[0036] Step b3: Dialyze the polymer precursor solution using a regenerated cellulose dialysis bag, then transfer it to a freeze dryer. First, pre-freeze it to -80℃ and maintain it for 12 hours, then freeze it at -40℃ for 24 hours, and then raise the temperature to 25℃ at 0.5℃ / min and maintain it for 12 hours to complete the freeze drying. After crushing it in a grinder, pass it through an 80-mesh sieve to obtain modified polyethylene glycol.

[0037] Furthermore, the preparation method of the modified carbon nanotubes includes the following steps:

[0038] Step C1: Immerse carbon nanotubes in concentrated nitric acid and sonicate for 2 hours, then wash until neutral and dry to obtain acid-oxidized carbon nanotubes.

[0039] Step C2: Dissolve zinc acetate and NaOH in an ethanol aqueous solution and stir evenly. Then add acid-oxidized carbon nanotubes and ultrasonically disperse for 30 min. Then react at 180℃ for 12 h. After natural cooling, the crude material is obtained.

[0040] Step C3: Centrifuge the coarse material, collect the precipitate, wash and dry it to obtain modified carbon nanotubes with zinc oxide quantum dots loaded on the surface.

[0041] Preferably, in step C1, the concentrated nitric acid has a mass fraction of 65%.

[0042] Preferably, in step S1, the ratio of carbon nanotubes to concentrated nitric acid is 1g:20mL.

[0043] Preferably, in step C2, the weight ratio of zinc acetate, NaOH, and carbon nanotubes from step C1 is 5:2:1.

[0044] Preferably, in step C2, the volume ratio of ethanol to water in the ethanol-water solution is 1:1.

[0045] Preferably, in step C2, the ratio of the total weight of zinc acetate and NaOH to the volume of the ethanol aqueous solution is 1g:20mL.

[0046] Preferably, in step C3, the centrifugation speed is 10,000 rpm and the time is 10 min.

[0047] Preferably, in step C3, the washing and drying conditions are: washing with ethanol 3-5 times and vacuum drying at 60°C for 2 hours.

[0048] Based on this, a preferred method for preparing modified carbon nanotubes is obtained, comprising the following steps:

[0049] Step c1: In an ultrasonic reactor, carbon nanotubes are immersed in concentrated nitric acid with a mass fraction of 65% at a dosage ratio of 1g:20mL and ultrasonically treated at 30Hz for 2h. Then, they are washed with deionized water until neutral and transferred to a vacuum drying oven and dried at 80℃ for 2h to obtain acid-oxidized carbon nanotubes.

[0050] Step c2: In an ultrasonic reactor, zinc acetate (5 times the amount of carbon nanotubes) and NaOH (2 times the amount of carbon nanotubes) are dissolved in an ethanol aqueous solution with a volume ratio of 1:1 and stirred evenly. Then, all the acid-oxidized carbon nanotubes obtained in step c1 are added and ultrasonically dispersed at 30 Hz for 30 min. The mixture is then reacted at 180 °C for 12 h and naturally cooled to obtain the coarse material.

[0051] Step c3: Transfer the coarse material to a centrifuge and centrifuge at 10,000 rpm for 10 min. Collect the precipitate, wash it three times with ethanol, and transfer it to a vacuum drying oven. Dry it under vacuum at 60°C for 2 h to obtain modified carbon nanotubes.

[0052] Preferably, the adjuvant is any one or a combination of alkyl polysaccharides, sucrose esters, and sophorolipids.

[0053] Secondly, the present invention also discloses a method for preparing the carbendazim-containing pesticide composition as described above, comprising the following steps:

[0054] Step 1: Prepare the raw materials according to the weight parts. Dissolve carbendazim and modified β-cyclodextrin in deionized water at 60℃ and stir magnetically for 12 hours. After freeze-drying, a white powder is obtained.

[0055] Step 2: Dissolve the white powder, modified polyethylene glycol, modified carbon nanotubes, and additives together in deionized water and stir at 300-400 rpm for 1.5 hours to obtain a pesticide composition containing carbendazim.

[0056] Based on this, a preferred method for preparing a pesticide composition containing carbendazim is obtained, comprising the following steps:

[0057] Step 1: Prepare 18 parts by weight of carbendazim, 12 parts by weight of modified β-cyclodextrin, 10 parts by weight of modified polyethylene glycol, 3 parts by weight of modified carbon nanotubes, 3 parts by weight of additives, and 60 parts by weight of deionized water; in a reaction vessel, dissolve carbendazim and modified β-cyclodextrin in deionized water at 60°C and stir magnetically for 12 hours, then freeze-dry to obtain a white powder;

[0058] Step 2: Dissolve the white powder, modified polyethylene glycol, modified carbon nanotubes, and additives together in deionized water and stir at 350 rpm for 1.5 h to obtain a pesticide composition containing carbendazim.

[0059] The beneficial effects of this invention are:

[0060] 1. The pesticide composition containing carbendazim of the present invention contains modified β-cyclodextrin, which has a hydrophobic cavity inside, which can connect with the benzene ring in carbendazim to encapsulate carbendazim therein, thereby achieving the effect of drug loading. It also improves the stability of drug loading by forming a hydrogen bond network structure with the amino group in carbendazim through the carboxyl group. Furthermore, after carboxymethylation, it can enhance water solubility, improve the uniformity of the pesticide composition, and enhance the effect of carbendazim.

[0061] 2. The pesticide composition containing carbendazim of the present invention contains modified polyethylene glycol, which is modified to introduce gallic acid ester bonds. When pathogens in the farmland secrete laccase, the gallic acid ester bonds are cleaved under the specific action of laccase, thereby releasing carbendazim from the pesticide composition. Without the action of laccase, the pesticide maintains a high sustained-release effect. Therefore, this pesticide composition can achieve the purpose of releasing the drug only at the site of fungal infection, while retaining the efficacy at the site without fungal infection, thus achieving controllable sustained-release effect.

[0062] 3. The pesticide composition containing carbendazim of the present invention contains modified carbon nanotubes with zinc oxide quantum dots loaded on its surface, which can produce a stronger bactericidal effect under visible light. Detailed Implementation

[0063] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0064] Unless otherwise specified, the experimental methods used in the following examples are conventional methods, performed according to the techniques or conditions described in the literature in this field or according to the product instructions. Unless otherwise specified, the materials and reagents used in the following examples are commercially available.

[0065] Preparation Example 1

[0066] The modified β-cyclodextrin was prepared by following these steps:

[0067] Step a1: In a stirred tank, dissolve β-cyclodextrin in a 10% NaOH solution at a ratio of 1g:10mL, and stir at 200rpm for 1h at 60℃ to obtain a mixture;

[0068] Step a2: Add chloroacetic acid (0.5 times the weight of β-cyclodextrin) dropwise to the mixture and stir until homogeneous. Then add 30% NaOH solution to adjust the pH to 12.5. React at 70°C for 6 hours to obtain the reaction solution.

[0069] Step a3: Add 30% hydrochloric acid dropwise to the reaction solution to adjust the pH of the reaction solution to 6.5. Add anhydrous ethanol in an amount equal to 0.1 times the volume of the reaction solution and stir well. Then transfer the mixture to a centrifuge and centrifuge at 8000 rpm for 10 min. Transfer the precipitate to a vacuum drying oven and vacuum dry at 80℃ for 2 h to obtain modified β-cyclodextrin.

[0070] Preparation Example 2

[0071] The modified polyethylene glycol is prepared by following these steps in sequence:

[0072] Step b1: In the reaction vessel, dissolve chitosan in a 20% acetic acid solution at a ratio of 1g:20mL and stir until homogeneous. Then add EDC (0.2 times the weight of chitosan) and NHS (0.12 times the weight of chitosan) and stir at 200rpm for 30min to obtain the activated solution.

[0073] Step b2: Add propyl gallate (0.5 times the weight of chitosan) to the activation solution and react at 40°C for 12 hours. Then add polyethylene glycol diglycidyl ether (0.8 times the weight of chitosan) and react at 60°C for 6 hours to obtain a polymer precursor solution.

[0074] Step b3: Dialyze the polymer precursor solution using a regenerated cellulose dialysis bag, then transfer it to a freeze dryer. First, pre-freeze it to -80℃ and maintain it for 12 hours, then freeze it at -40℃ for 24 hours, and then raise the temperature to 25℃ at 0.5℃ / min and maintain it for 12 hours to complete the freeze drying. After crushing it in a grinder, pass it through an 80-mesh sieve to obtain modified polyethylene glycol.

[0075] Preparation Example 3

[0076] The modified carbon nanotubes were prepared by following these steps:

[0077] Step c1: In an ultrasonic reactor, carbon nanotubes are immersed in concentrated nitric acid with a mass fraction of 65% at a dosage ratio of 1g:20mL and ultrasonically treated at 30Hz for 2h. Then, they are washed with deionized water until neutral and transferred to a vacuum drying oven and dried at 80℃ for 2h to obtain acid-oxidized carbon nanotubes.

[0078] Step c2: In an ultrasonic reactor, zinc acetate (5 times the amount of carbon nanotubes) and NaOH (2 times the amount of carbon nanotubes) are dissolved in an ethanol aqueous solution with a volume ratio of 1:1 and stirred evenly. Then, all the acid-oxidized carbon nanotubes obtained in step c1 are added and ultrasonically dispersed at 30 Hz for 30 min. The mixture is then reacted at 180 °C for 12 h and naturally cooled to obtain the coarse material.

[0079] Step c3: Transfer the coarse material to a centrifuge and centrifuge at 10,000 rpm for 10 min. Collect the precipitate, wash it three times with ethanol, and transfer it to a vacuum drying oven. Dry it under vacuum at 60°C for 2 h to obtain modified carbon nanotubes.

[0080] Example 1

[0081] The preparation of a pesticide composition containing carbendazim is carried out according to the following steps:

[0082] Step 1: Prepare 18 parts by weight of carbendazim, 12 parts by weight of modified β-cyclodextrin from Preparation Example 1, 10 parts by weight of modified polyethylene glycol from Preparation Example 2, 3 parts by weight of modified carbon nanotubes from Preparation Example 3, 3 parts by weight of alkyl polysaccharide, and 60 parts by weight of deionized water; in a reaction vessel, dissolve carbendazim and modified β-cyclodextrin in deionized water at 60°C and stir magnetically for 12 hours, then freeze-dry to obtain a white powder;

[0083] Step 2: Dissolve the white powder, modified polyethylene glycol, modified carbon nanotubes, and alkyl polysaccharide together in deionized water and stir at 350 rpm for 1.5 h to obtain a pesticide composition containing carbendazim.

[0084] Example 2

[0085] The preparation of a pesticide composition containing carbendazim is carried out according to the following steps:

[0086] Step 1: Prepare 15 parts by weight of carbendazim, 10 parts by weight of modified β-cyclodextrin from Preparation Example 1, 8 parts by weight of modified polyethylene glycol from Preparation Example 2, 2 parts by weight of modified carbon nanotubes from Preparation Example 3, 2 parts by weight of alkyl polysaccharide, and 50 parts by weight of deionized water; in a reaction vessel, dissolve carbendazim and modified β-cyclodextrin in deionized water at 60°C and stir magnetically for 12 hours, then freeze-dry to obtain a white powder;

[0087] Step 2: Dissolve the white powder, modified polyethylene glycol, modified carbon nanotubes, and alkyl polysaccharide together in deionized water and stir at 350 rpm for 1.5 h to obtain a pesticide composition containing carbendazim.

[0088] Example 3

[0089] The preparation of a pesticide composition containing carbendazim is carried out according to the following steps:

[0090] Step 1: Prepare 20 parts by weight of carbendazim, 15 parts by weight of modified β-cyclodextrin from Preparation Example 1, 12 parts by weight of modified polyethylene glycol from Preparation Example 2, 4 parts by weight of modified carbon nanotubes from Preparation Example 3, 4 parts by weight of alkyl polysaccharide, and 65 parts by weight of deionized water; in a reaction vessel, dissolve carbendazim and modified β-cyclodextrin in deionized water at 60°C and stir magnetically for 12 hours, then freeze-dry to obtain a white powder;

[0091] Step 2: Dissolve the white powder, modified polyethylene glycol, modified carbon nanotubes, and alkyl polysaccharide together in deionized water and stir at 350 rpm for 1.5 h to obtain a pesticide composition containing carbendazim.

[0092] Example 4

[0093] Compared with Example 1, the only difference is that the alkyl polysaccharide is replaced with sucrose ester, while the other steps and conditions remain the same, and a pesticide composition containing carbendazim is finally obtained.

[0094] Example 5

[0095] Compared with Example 1, the only difference is that the alkyl polyglycoside is replaced with sophorolipid, while the other steps and conditions remain the same, and a pesticide composition containing carbendazim is finally obtained.

[0096] Comparative Example 1

[0097] Compared with Example 1, the only difference is that the modified β-cyclodextrin in Preparation Example 1 was replaced with β-cyclodextrin, while the other steps and conditions remained the same, and a pesticide composition containing carbendazim was finally obtained.

[0098] Comparative Example 2

[0099] Compared with Example 1, the only difference is that the modified polyethylene glycol in Preparation Example 2 was replaced with polyethylene glycol, while the other steps and conditions remained the same, and a pesticide composition containing carbendazim was finally obtained.

[0100] Comparative Example 3

[0101] Compared with Example 1, the only difference is that the modified polyethylene glycol in Preparation Example 2 was omitted, while the other steps and conditions remained the same, and a pesticide composition containing carbendazim was finally obtained.

[0102] Comparative Example 4

[0103] Compared with Example 1, the only difference is that the modified carbon nanotubes in Preparation Example 3 were replaced with carbon nanotubes, while the other steps and conditions remained the same, and a pesticide composition containing carbendazim was finally obtained.

[0104] Comparative Example 5

[0105] Compared with Example 1, the only difference is that the modified carbon nanotubes in Preparation Example 3 were omitted, while the other steps and conditions remained the same, and a pesticide composition containing carbendazim was finally obtained.

[0106] The pesticide compositions containing carbendazim prepared in Examples 1-5 and Comparative Examples 1-5, or the white powder in step 1 of the preparation process, were subjected to performance tests, including drug loading effect, sustained release effect, laccase effect, and fungicidal effect. The specific test methods are as follows:

[0107] Drug loading efficiency: High performance liquid chromatography (HPLC) was used with a C18 column and a mobile phase of methanol-water solution with a volume ratio of 7:3. The detection wavelength was 280 nm. The actual drug loading rate of carbendazim in the white powder obtained in step 1 was calculated by the standard curve method.

[0108] Sustained-release effect: The pesticide composition containing carbendazim was dispersed in phosphate buffer solution at pH 5.5 and shaken at 100 rpm at 37°C for 24 hours. The release rate was then measured by sampling.

[0109] Effect of laccase on efficacy: The pesticide composition containing carbendazim was placed in PBS buffer containing 5 U / mL laccase (environment 1) and without laccase (environment 2) (pH 6.0), and the release rate of carbendazim under the two environments was monitored by HPLC within 4 h.

[0110] Bactericidal effect: The plate inhibition zone method was used. The pesticide composition containing carbendazim was spread on PDA medium, and filter paper containing the drug was placed on it. The diameter of the inhibition zone was measured.

[0111] The test results are listed in Table 1, as follows:

[0112] Table 1

[0113]

[0114] Analysis of the data in Table 1 shows that, compared to Comparative Example 1, the white powder obtained in step 1 of Examples 1-5 exhibits a significantly stronger loading effect on carbendazim, and the resulting carbendazim-containing pesticide compositions have significantly stronger sustained-release rates and fungicidal effects; compared to Comparative Examples 2-3, the carbendazim-containing pesticide compositions obtained in Examples 1-5 exhibit a significantly stronger laccase-affecting effect; and compared to Comparative Examples 4-5, the carbendazim-containing pesticide compositions obtained in Examples 1-5 exhibit a significantly stronger fungicidal effect.

[0115] The foregoing has provided a detailed description of one embodiment of the present invention, but this description is merely a preferred embodiment and should not be construed as limiting the scope of the invention. All equivalent variations and modifications made within the scope of the claims of this invention should still fall within the patent coverage of this invention.

Claims

1. A pesticide composition containing carbendazim, characterized in that, The product comprises the following components by weight: 15-20 parts carbendazim, 10-15 parts modified β-cyclodextrin, 8-12 parts modified polyethylene glycol, 2-4 parts modified carbon nanotubes, 2-4 parts additives, and 50-65 parts deionized water. The modified β-cyclodextrin has carboxymethyl groups attached to its surface; the modified polyethylene glycol has gallate bonds attached to its surface; and the modified carbon nanotubes are coated with zinc oxide quantum dots.

2. The pesticide composition containing carbendazim according to claim 1, characterized in that, The preparation method of the modified β-cyclodextrin includes the following steps: Step A1: Dissolve β-cyclodextrin in NaOH solution and stir at 60℃ for 1 hour to obtain a mixed solution; Step A2: Add chloroacetic acid dropwise to the mixture and stir until homogeneous. Then adjust the pH to 12-13 and react at 70°C for 6 hours to obtain the reaction solution. Step A3: Adjust the pH of the reaction solution to 6.5, add anhydrous ethanol, centrifuge, and vacuum dry the precipitate to obtain modified β-cyclodextrin.

3. The pesticide composition containing carbendazim according to claim 2, characterized in that, In step A2, the weight ratio of chloroacetic acid to β-cyclodextrin in step A1 is 1:

2.

4. The pesticide composition containing carbendazim according to claim 1, characterized in that, The method for preparing the modified polyethylene glycol includes the following steps: Step B1: Dissolve chitosan in acetic acid solution and stir until homogeneous. Then add 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide and stir for 30 minutes to obtain an activated solution. Step B2: Add propyl gallate to the activation solution and react at 40°C for 12 hours. Then add polyethylene glycol diglycidyl ether and react at 60°C for 6 hours to obtain a polymer precursor solution. Step B3: The polymer precursor solution is dialyzed and freeze-dried sequentially, and then pulverized to obtain modified polyethylene glycol.

5. The pesticide composition containing carbendazim according to claim 4, characterized in that, In step B1, the weight ratio of chitosan, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide is 10:2:1.

2.

6. The pesticide composition containing carbendazim according to claim 4, characterized in that, In step B2, the weight ratio of propyl gallate, polyethylene glycol diglycidyl ether, and chitosan in step B1 is 5:8:

10.

7. The pesticide composition containing carbendazim according to claim 1, characterized in that, The method for preparing the modified carbon nanotubes includes the following steps: Step C1: Immerse carbon nanotubes in concentrated nitric acid and sonicate for 2 hours, then wash until neutral and dry to obtain acid-oxidized carbon nanotubes. Step C2: Dissolve zinc acetate and NaOH in an ethanol aqueous solution and stir evenly. Then add acid-oxidized carbon nanotubes and ultrasonically disperse for 30 min. Then react at 180℃ for 12 h. After natural cooling, the crude material is obtained. Step C3: Centrifuge the coarse material, collect the precipitate, wash and dry it to obtain modified carbon nanotubes.

8. The pesticide composition containing carbendazim according to claim 7, characterized in that, In step C2, the weight ratio of zinc acetate, NaOH, and carbon nanotubes from step C1 is 5:2:

1.

9. The pesticide composition containing carbendazim according to claim 1, characterized in that, The adjuvant is any one or more of alkyl polysaccharide glycosides, sucrose esters, and sophorolipids.

10. A method for preparing a pesticide composition containing carbendazim as described in any one of claims 1-9, characterized in that, Includes the following steps: Step 1: Prepare the raw materials according to the weight parts. Dissolve carbendazim and modified β-cyclodextrin in deionized water at 60℃ and stir magnetically for 12 hours. After freeze-drying, a white powder is obtained. Step 2: Dissolve the white powder, modified polyethylene glycol, modified carbon nanotubes, and additives together in deionized water and stir at 300-400 rpm for 1.5 hours to obtain a pesticide composition containing carbendazim.

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