Long-acting slow-release nano pesticide preparation as well as preparation method and application thereof
The nanopestic preparation prepared by the reaction of amphiphilic polymer and Schiff base solves the problems of low utilization and loss of pesticide preparations, achieves high adhesion and long-term sustained release, and reduces pesticide usage and environmental pollution.
Patent Information
- Application Number
- CN202510411999.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-02
- Publication Date
- 2025-07-04
AI Technical Summary
The existing pesticide preparations have problems such as low target utilization, poor dispersion, large doses of use, and easy loss. The behavior of pesticides in the field is affected by factors such as climate and soil, resulting in environmental pollution and waste of resources.
A long-acting sustained-release nanopestic preparation is prepared using amphiphilic polymers. The pesticides are coupled to the polymer through Schiff base reaction, hydroxyl and carboxy groups are introduced to improve adhesion, and nanoparticles are formed through active radical polymerization to achieve slow release.
It achieves high adhesion and long-term sustained release of pesticides on plant leaves, reduces the dose and number of administration, reduces the risk of loss, adapts to complex environments, and has a simple and environmentally friendly preparation process.
Smart Images
Figure CN120240432A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of nano-pesticide formulations, and particularly to a long-acting and slow-release nano-pesticide formulation, a preparation method and an application thereof. Technical Background
[0002] Pest control plays a crucial role in agricultural production. Although the use of various pesticides can effectively reduce pests and diseases, most current pesticide formulations have problems such as low target utilization rate, poor dispersibility, large application dosage, and easy loss to water areas and soil. Therefore, the development of environmentally friendly and highly efficient pesticide formulations meets the requirements of the market and the environment. Nano-pesticides, as a new type of pesticide formulation, can significantly improve the biological activity, utilization rate and persistence period of the active ingredients of pesticides, reduce the application dosage and frequency of pesticides, reduce pesticide loss and accelerate the degradation of residues.
[0003] During the application process of most pesticide formulations, the behavior of pesticides in the field includes processes such as volatilization, degradation, adsorption and loss, which are affected by various factors such as climatic conditions, soil properties and crop growth status. For example, after rain, the humidity of the farmland increases, which may accelerate the degradation rate of pesticides, especially those that are easily hydrolyzed. If there is more surface water accumulation, pesticides may also be lost, resulting in environmental pollution and waste of resources. Summary of the Invention
[0004] The purpose of the present application is to overcome the above-mentioned defects or problems in the background technology, and to provide a long-acting and slow-release nano-pesticide formulation, a preparation method and an application thereof. Compared with the prior art, on the premise of increasing the slow-release time of nano-pesticides, it can further increase the adhesion of nano-pesticides on plant leaves, or provide a material basis or preparation method for achieving the above effects.
[0005] To achieve the above purpose, the following technical solutions are adopted:
[0006] The first technical solution relates to a long-acting and slow-release nano-pesticide formulation; the long-acting and slow-release nano-pesticide formulation includes an amphiphilic polymer and its aqueous dispersion; the hydrophilic chain segment on the amphiphilic polymer is composed of hydrophilic chain units; the hydrophobic chain segment on the amphiphilic polymer is composed of hydrophobic chain units; at least part of the polymer also includes functional chain units copolymerized on the hydrophobic chain segment and / or the hydrophilic chain segment; the functional chain units are defined as chain units conjugated with organic pesticides; at least part of the polymer also includes adhesion chain units copolymerized on the hydrophobic chain segment and / or the hydrophilic chain segment;
[0007] The second technical solution is based on the first technical solution, wherein at least part of the polymer further comprises a link segment to be modified copolymerized with the hydrophobic segment and / or the hydrophobic segment, the link segment to be modified is conjugated with a reactive group, and the reactive group conjugates the pesticide through a Schiff base reaction; at least part of the polymer further comprises an adhesion link segment copolymerized with the hydrophobic segment and / or the hydrophobic segment.
[0008] The third technical solution is based on the first technical solution, wherein in the amphiphilic polymer, the polymerization group is a group suitable for living radical polymerization reaction, and the polymerization group is preferably methacrylate and / or acrylate.
[0009] The fourth technical solution is based on the first technical solution, wherein the group to be modified is preferably an aldehyde group or a ketone.
[0010] The fifth technical solution is based on the first technical solution, wherein the adhesion link segment comprises a group capable of generating a large number of hydrogen bonds; the group on the adhesion link segment is preferably a hydroxyl group or a carboxyl group.
[0011] The sixth technical solution is based on the first technical solution, wherein the pesticide is an organic pesticide containing a primary amine or a secondary amine; the organic pesticide is preferably emamectin benzoate.
[0012] The seventh technical solution is based on the first technical solution, wherein the average molecular weight of the amphiphilic polymer in the long-acting and slow-release nano-pesticide formulation is 10,000 - 100,000.
[0013] The eighth technical solution is based on the first to seventh technical solutions, wherein the hydrodynamic diameter of the nano-pesticide dispersed in water is between 10 - 1000 nm.
[0014] The ninth technical solution is based on the first to seventh technical solutions, wherein the loading rate of the nano-pesticide is between 0.1 - 50%.
[0015] The tenth technical solution is based on the first to seventh technical solutions, wherein the longest effective slow-release time of the nano-pesticide is 7 - 40 days.
[0016] The eleventh technical solution relates to the use of a long-acting and slow-release nano-pesticide formulation, wherein the long-acting and slow-release nano-pesticide formulation as described in any one of the first to tenth technical solutions is applied in pest control.
[0017] The twelfth technical solution relates to a preparation method of a long-acting and slow-release nano-pesticide formulation, which is characterized in that:
[0018] Two or three segments are formed through living radical reactions, one of the two adjacent segments being the hydrophilic segment and the other being the hydrophobic segment; the hydrophilic segment is composed of polymerization of hydrophilic monomers and / or direct use of hydrophilic polymers, and the hydrophilic monomers form hydrophilic linkages in the hydrophilic segment; the hydrophobic segment is formed by polymerization of hydrophobic monomers, and the hydrophobic monomers form the hydrophobic linkages in the hydrophobic segment;
[0019] The conjugated functional monomers are copolymerized into the corresponding segments during the formation of at least one segment; the adhesion linkages are copolymerized into the corresponding segments during the formation of at least one segment;
[0020] The long-acting and slow-release nano-pesticide formulation is prepared by directly dissolving the amphiphilic polymer loaded with pesticides in water or an aqueous solution.
[0021] The thirteenth technical solution is based on the twelfth solution, wherein the functional monomers are prepared by Schiff base reaction of pesticides and monomers to be reacted.
[0022] Based on the prior art, the above solutions have the following beneficial effects:
[0023] (1) In the present invention, pesticides are coupled to amphiphilic polymers using Schiff base reactions. Utilizing the reversible transformation of Schiff base products, slow release under weak acids or weak bases can be achieved, effectively reducing the application dosage and frequency of pesticides.
[0024] (2) For the long-acting and slow-release nano-pesticide formulation of the present invention, by introducing a large number of hydroxyl and carboxyl groups onto the polymer, high adhesion on plant leaves is achieved, effectively avoiding the loss of pesticides caused by rainwashing.
[0025] (3) The preparation process of the long-acting and slow-release nano-pesticide formulation of the present invention is simple and safe, effectively reducing the use of organic solvents, and it is an environmentally friendly nano-pesticide formulation. Description of the Drawings
[0026] Figure 1 is the release curve of the nano-pesticide formulation in different pH buffer solutions in Example 1;
[0027] Figure 2 is the residue rate of the nano-pesticide on the leaves at different deionized water spraying speeds in Example 1;
[0028] Figure 3 is the residue amount of the nano-pesticide on the non-woven fabric within 6 weeks in the outdoor environment in Example 1;
[0029] Figure 4 is the residue rate of the nano-pesticide on the leaves at different deionized water spraying speeds in Example 2;
[0030] Figure 5 Residual rate of nano - pesticides on leaves under different deionized water spraying speeds in Example 3
[0031] Figure 6 Residual rate of nano - pesticides on leaves under different deionized water spraying speeds in Comparative Example 1
[0032] Figure 7 Release curve of nano - pesticide formulation in deionized water in Comparative Example 1
[0033] Figure 8 Residual rate of nano - pesticides on leaves under different deionized water spraying speeds in Comparative Example 2 Specific implementation method
[0035] The present invention will be further described below in conjunction with specific implementation cases. Unless otherwise specified, the raw materials of the present invention are all commercially available.
[0036] Example 1
[0037] The polymer single chain in Example 1 includes at least one hydrophilic segment and at least one hydrophobic segment of block copolymerization. The polymer single chain has a linear structure. In the hydrophilic segment, hydrophilic chain units and adhesion chain units are included. In the hydrophobic segment, hydrophobic chain units and functional chain units are included. In Example 1, the polymer molecular formula is P-(OEGMA 40-CO -MMA 10 )-b-(nBMA 30-CO -(MA - EB)). Where OEGMA is oligoethylene glycol methacrylate (average molecular weight is 300). MMA is methacrylic acid. nBMA is n - butyl methacrylate. MA - EB is a functional chain segment conjugated with emamectin benzoate.
[0038] In the process of preparing the polymer, first, an amphiphilic intermediate polymer was prepared, and emamectin benzoate was conjugated to the polymer through a Schiff base reaction.
[0039] Step 1: Preparation of hydrophilic segment by living radical polymerization
[0040] In Example 1, the living radical polymerization reaction selects reversible addition - fragmentation chain transfer (RAFT) polymerization reaction. The chain transfer agent is 4 - cyano - 4-(thiobenzoyl) pentanoic acid (CTA). The hydrophilic monomer is oligoethylene glycol methacrylate (OEGMA), and methacrylic acid (MMA) is the adhesion monomer.
[0041] First, dissolve 56 mg (0.2 mmol) of CTA, 3.42 g (9.41 mmol) of OEGMA′, 0.2 g (2.3 mmol) of MMA, and 3.3 mg (0.02 mmol) of AIBN in 15 mL of 1,4-dioxane and add 3 to 4 drops of anisole. The mixed solution is reacted in a Schlenk tube, and the conversion rate is monitored by nuclear magnetic resonance hydrogen spectroscopy. The reaction conditions are to raise the temperature to 70 °C after deoxygenation. During the reaction, an appropriate amount of the mixed solution is taken to monitor the conversion rate by nuclear magnetic resonance hydrogen spectroscopy. When the conversion rate reaches 85.2%, oxygen is introduced to stop the reaction. After the reaction is completed, the temperature is lowered to room temperature, and the supernatant is removed after precipitation in n-hexane and dried under vacuum at room temperature to obtain 2.47 g of the hydrophilic segment. The molecular formula of the hydrophilic segment is P-(OEGMA 40-CO -MMA 10 ). The hydrophilic monomer forms a hydrophilic link in the hydrophilic segment.
[0042] Step 2: Prepare the intermediate polymer by living radical polymerization:
[0043] The chain transfer agent for the living radical polymerization reaction is the hydrophilic segment (P-(OEGMA 40-CO -MMA 10 )) prepared in Step 1. The hydrophobic monomer is n-butyl methacrylate (nBMA), and the monomer to be modified is 4-oxobutyl 2-methyl-2-acrylate (OBMA, prepared according to the literature "Organic & Biomolecular Chemistry (2009), 7(7), 1461 - 1470").
[0044] First, dissolve 1.29 g (0.1 mmol) of (P-(OEGMA 40-CO -MMA 10 ), 0.5 g (3.5 mmol) of nBMA, 0.22 g (1.4 mmol) of OBMA, and 3.3 mg (0.02 mmol) of AIBN in 15 mL of 1,4-dioxane and add 3 to 4 drops of anisole. The mixed solution is reacted in a Schlenk tube, and the conversion rate is monitored by nuclear magnetic resonance hydrogen spectroscopy. The reaction conditions are to raise the temperature to 70 °C after deoxygenation. During the reaction, an appropriate amount of the mixed solution is taken to monitor the conversion rate by nuclear magnetic resonance hydrogen spectroscopy. When the conversion rate reaches 85.4%, oxygen is introduced to stop the reaction. After the reaction is completed, the temperature is lowered to room temperature, and the supernatant is removed after precipitation in n-hexane and dried under vacuum at room temperature to obtain 1.79 g of the intermediate polymer. The molecular formula of the intermediate polymer is P-(OEGNA 40-CO -MMA 10 )-b-(nBMA 30-CO -OBMA 12 ). The hydrophilic monomer forms a hydrophilic link in the hydrophilic segment.
[0045] Step 3: Modify emamectin benzoate to the intermediate polymer through Schiff base reaction:
[0046] First, dissolve 1.5 g of P-(OEGNA 40-CO -MMA 10 )-b-(nBMA 30-CO -OBMA 12 ), 2.5 g of emamectin benzoate (EB) in 20 mL of acetone, add 5 g of anhydrous potassium carbonate, and stir the reaction at room temperature for 24 hours. After the reaction is completed, filter to remove the insoluble substances, completely spin-dry the obtained mixed solution, then add 15 mL of tetrahydrofuran to redissolve, and filter to remove the insoluble substances. Then completely spin-dry the tetrahydrofuran to obtain 2.4 g of P-(OEGNA 40-CO -MMA 10 )-b-(nBMA 30-CO -(MA-EB)).
[0047] Disperse the polymer P-(OEGNA 40-CO -MMA 10 )-b-(nBMA 30-CO -(MA-EB)) in water to obtain a long-acting and slow-release nano-pesticide formulation. The average hydrodynamic diameter of the nano-pesticide formulation is measured to be 98.3 nm by dynamic light scattering.
[0048] Place the nano-pesticide formulation of Example 1 in a dialysis bag with a molecular weight cut-off of 5 kDa, and then dialyze it in buffer solutions with pH values of 6.0, 7.4, and 8.5 respectively at room temperature. Take an appropriate amount of the dialysis solution within 15 days for quantitative determination of the proportion of emamectin benzoate released by a visible-ultraviolet absorption spectrometer.
[0049] Figure 1 Shows the release curves of the nano-pesticide formulation in Example 1 in different pH buffer solutions. As Figure 1 shown, for the nano-pesticide formulation prepared in Example 1, when the pH is 7.4, the release rate is slow, and about 10% is released within 15 days. When the pH is 6.0, about 32% is released within 15 days. When the pH is 8.5, about 40% is released within 15 days.
[0050] Spray the nano-pesticide formulation of Example 1 on the leaves respectively, and detect the retention rate after being washed by water. Specifically, cut 25 leaves with a size of 2×3 cm, arrange them evenly and neatly on a flat surface, then spray the nano-pesticide formulation of Example 1 evenly on the 25 leaves, and let it stand for 6 hours until the leaf surface is completely dry. Divide the 25 leaves into 5 groups, and respectively use 1 mL·dm -2 / min, 2 mL·dm -2 / min, 5 mL·dm -2 / min, 10 mL·dm -2Spray deionized water at a speed of / min for 30 min. Those without any treatment were used as the control group. After spraying, the leaves were completely dried. Subsequently, the leaves were placed in tetrahydrofuran and ultrasonically treated for 15 min. After removing the leaves, the solvent was completely dried by rotary evaporation and then dispersed with deionized water, and the nano-pesticides retained on the leaves were quantified using a visible-ultraviolet absorption spectrometer. Residual rate = M t / M0×100%, M t is the content of nano-pesticides on the leaves at different spraying speeds, and M0 is the content of nano-pesticides on the leaves without spraying.
[0051] Figure 2 shows the residual rate of nano-pesticides on the leaves at different deionized water spraying speeds in Example 1. As Figure 2 shown, when spraying deionized water at a speed of 1 mL·dm -2 / min for 30 min, no obvious loss of nano-pesticides was observed; when the spraying speed reached 10 mL·dm -2 / min, only about 6% of the nano-pesticides were lost after 30 min. This shows that the nano-pesticides prepared in Example 1 have good adhesion performance on plant leaves.
[0052] The nano-pesticide formulations of Example 1 were respectively infiltrated into non-woven fabrics, and the long-term slow-release effect in the natural environment was detected. Specifically, 35 pieces of non-woven fabrics with a size of 10×10 cm were cut. All the non-woven fabrics were immersed in the nano-pesticide formulations of Example 1, and then fished out and naturally dried for 6 h. Among them, 5 pieces of non-woven fabrics were reserved as the control group, and after being soaked in tetrahydrofuran and treated, the initial nano-pesticide content on the non-woven fabrics was tested using a visible-ultraviolet absorption spectrometer. The remaining 30 pieces were placed on an open rooftop and fixed with clamps. Subsequently, 5 pieces of non-woven fabrics were taken every week. After ultrasonic treatment in tetrahydrofuran for 15 min, the solvent was dried by rotary evaporation, then dispersed with deionized water, and the nano-pesticide content on the non-woven fabrics was tested using a visible-ultraviolet absorption spectrometer. Residual rate = M n / M o ×100%, M n is the nano-pesticide content on the non-woven fabrics at different times, and M o is the nano-pesticide content on the non-treated non-woven fabrics.
[0053] Figure 3 shows the residual amount of nano-pesticides on the non-woven fabrics in the outdoor environment within 6 weeks in Example 1. As Figure 3 shown, the non-woven fabrics infiltrated with nano-pesticides showed almost linear release in the outdoor environment. The small deviation may be caused by rain. At the 6th week, the retention rate of nano-pesticides on the non-woven fabrics decreased to 2.7%. This shows that the nano-pesticide formulations of Example 1 can still maintain long-term and stable release in the outdoor environment.
[0054] Example 2
[0055] The polymer molecular formula of Example 2 is P-(OEGNA 50-CO -MMA 15 )-b-(nBMA 35-CO -(MA-EB)). The intermediate polymer in Example 2 is P-(OEGNA 50-CO -MMA 15 )-b-(nBMA 35-CO -OBMA 15 ), where the number of hydrophilic linkers is 50, the number of adhesion linkers is 15, the number of hydrophobic linkers is 35, and the number of linkers to be modified is 15. Emamectin benzoate is modified on the polymer through a Schiff base reaction. The rest of the polymer in Example 2 is the same as that in Example 1.
[0056] The preparation method of the polymer in Example 2 is the same as that in Example 1 except for the specific parameters.
[0057] In the nano-pesticide formulation of Example 2, the average hydrated particle size of the nano-pesticide is 145.3 nm. The rest of the nano-pesticide formulation in Example 2 is the same as that in Example 1.
[0058] The preparation method of the nano-pesticide formulation in Example 2 is the same as that in Example 1.
[0059] Figure 4 Shows the residue rate of the nano-pesticide on the leaves at different deionized water spraying speeds in Example 2. The spraying speed of the nano-pesticide formulation in Example 2 is selected as 5 mL·dm -2 / min, 10 mL·dm -2 / min, the spraying time is 1 hour, and other experimental methods are the same as those in Example 1. As Figure 4 shown, when deionized water is sprayed at a speed of 5 mL·dm -2 / min for 1 hour, the residue rate of the nano-pesticide on the leaves is 92.5%; when deionized water is sprayed at a speed of 10 mL·dm -2 / min for 1 hour, the residue rate of the nano-pesticide on the leaves is 89.53%.
[0060] Example 3
[0061] The polymer molecular formula of Example 3 is P-(OEGMA 50-CO -MMA 20 )-b-(nBMA 25-CO -(MA-EB)). The intermediate polymer in Example 3 is P-(OEGNA 50-CO -MMA 20 )-b-(nBMA 25-CO -OBMA 12) Among them, the number of hydrophilic linkages is 50, the number of adhesion linkages is 20, the number of hydrophobic linkages is 25, and the number of linkages to be modified is 12. Emamectin benzoate is modified on the polymer through a Schiff base reaction. The rest of the polymer in Example 3 is the same as that in Example 2.
[0062] The preparation method of the polymer in Example 3 is the same as that in Example 2 except for the specific parameters.
[0063] In the nano-pesticide formulation of Example 3, the average hydrated particle size of the nano-pesticide is 109.5 nm. The rest of the nano-pesticide formulation in Example 2 is the same as that in Example 2.
[0064] The preparation method of the nano-pesticide formulation in Example 3 is the same as that in Example 2.
[0065] Figure 5 Shows the residue rate of the nano-pesticide on the leaves at different deionized water spraying speeds in Example 3. The spraying speed of the nano-pesticide formulation in Example 3 was selected as 5 mL·dm -2 / min, 10 mL·dm -2 / min, the spraying time was 1 hour, and other experimental methods were the same as those in Example 2. As Figure 5 shown, when deionized water was sprayed at a speed of 5 mL·dm -2 / min for 1 hour, the residue rate of the nano-pesticide on the leaves was 94.2%; when deionized water was sprayed at a speed of 10 mL·dm -2 / min for 1 hour, the residue rate of the nano-pesticide on the leaves was 90.5%.
[0066] Comparative Example 1
[0067] The molecular formula of the polymer in Comparative Example 1 is P-OEGNA 50 -b-nBMA 35 , which includes a hydrophilic segment and a hydrophobic segment. Emamectin benzoate and P-OEGNA 50 -b-nBMA 35 were dissolved together in acetone, and then deionized water was added dropwise. After the mixed solution was stirred for 4 h, acetone was removed by dialysis to obtain the nano-pesticide formulation.
[0068] Figure 6 Shows the residue rate of the nano-pesticide on the leaves at different deionized water spraying speeds in Comparative Example 1. The spraying speed of the nano-pesticide formulation in Comparative Example 1 was selected as 5 mL·dm -2 / min, 10 mL·dm -2 / min, the spraying time was 30 min, and other experimental methods were the same as those in Example 2. As Figure 6 shown, at 5 mL·dm -2Spray deionized water at a speed of / min for 30 min, and the residue rate of the nano-pesticide on the leaves is 23.2%; at 10 mL·dm -2 Spray deionized water at a speed of / min for 30 min, and the residue rate of the nano-pesticide on the leaves is 11.4%. The nano-pesticide without the introduction of adhesion linkers and uncoupled emamectin benzoate cannot maintain the retention amount on the leaves in a simulated rain environment.
[0069] Place the nano-pesticide preparation of Comparative Example 1 in a 5 kDa dialysis bag, and then dialyze it in deionized water at room temperature. Take an appropriate amount of the dialysis solution within 15 days for quantifying the proportion of emamectin benzoate released by a visible-ultraviolet absorption spectrometer. See Figure 7 , Figure 7 shows the release curve of the nano-pesticide preparation in Comparative Example 1 in deionized water. As Figure 7 shown, the nano-pesticide preparation prepared in Comparative Example 1 released 79.1% cumulatively in 5 days and 93.7% cumulatively in 15 days in deionized water.
[0070] Comparative Example 2
[0071] The polymer in Comparative Example 2 is commercially available Pluronic F-127. Emamectin benzoate and Pluronic F-127 are dissolved in acetone together, and then deionized water is added dropwise. After the mixed solution is stirred for 4 h, acetone is removed by dialysis to obtain the nano-pesticide preparation.
[0072] Figure 8 shows the residue rate of the nano-pesticide on the leaves at different deionized water spraying speeds in Comparative Example 2. The spraying speed of the nano-pesticide preparation in Comparative Example 1 is selected as 5 mL·dm -2 / min, 10 mL·dm -2 / min, the spraying time is 30 min, and other experimental methods are the same as those in Example 2. As Figure 8 shown, when spraying deionized water at a speed of 5 mL·dm -2 / min for 30 min, the residue rate of the nano-pesticide on the leaves is 17.3%; when spraying deionized water at a speed of 10 mL·dm -2 / min for 30 min, the residue rate of the nano-pesticide on the leaves is 7.1%. The nano-pesticide formed by the commercially available amphiphilic polymer cannot maintain the retention amount on the leaves in a simulated rain environment.
[0073] In the above examples, the applicant prepared an amphiphilic polymer by block copolymerization. "Front-segment copolymerization" does not include random copolymerization.
[0074] In addition, the above embodiments and comparative examples are purposefully extracted from a large amount of experimental data, and do not represent that there is only the experimental data of the above embodiments and comparative examples. Describing the above embodiments and comparative examples is only to illustrate the basis for the applicant to select relevant parameters.
[0075] In the above embodiments, if the nano-pesticide formulation still maintains a high residue rate after being rinsed with deionized water, it means that the nano-pesticide formulation has good rain erosion resistance.
[0076] From Comparative Example 1 and Embodiment 1, it can be seen that the polymer without the introduction of adhesion linkages cannot maintain rain erosion resistance. Moreover, without introducing emamectin benzoate into the nano-pesticide by coupling, the release rate of emamectin benzoate will be accelerated.
[0077] From Comparative Example 2 and Embodiment 1, it can be seen that the nano-pesticide formulation prepared by loading pesticides with commercial amphiphilic polymers does not have obvious rain erosion resistance.
[0078] The nano-pesticide formulation of the present application has good adhesion performance and long-acting slow-release effect in pest control. Compared with the prior art, the nano-pesticide formulation of the present application can significantly reduce the application dose and application frequency of pesticides. At the same time, the preparation method of the nano-pesticide formulation of the present application is simple, without the use of heavy metal catalysts, reducing the use of organic solvents, and has broad application prospects.
[0079] The description of the above specification and embodiments is used to explain the protection scope of the present application, but does not constitute a limitation on the protection scope of the present application.
Claims
1. A long-acting and sustained-release nano-pesticide preparation, characterized in that: The long-acting and sustained-release nano-pesticide formulation comprises an amphiphilic polymer or its aqueous dispersion; the hydrophilic chain segment on the amphiphilic polymer consists of hydrophilic chain units; the hydrophobic chain segment on the amphiphilic polymer consists of hydrophobic chain units; the polymer further comprises functional chain units copolymerized on the hydrophobic chain segment and / or the hydrophilic chain segment; the polymer further comprises adhesion chain units copolymerized on the hydrophobic chain segment and / or the hydrophilic chain segment; The functional chain unit is defined as the chain unit conjugated with the organic pesticide; it is composed of a to-be-modified chain unit copolymerized on the hydrophobic chain segment and / or the hydrophilic chain segment and an organic pesticide link, the to-be-modified chain unit is conjugated with a to-be-reacted group, and the to-be-reacted group is conjugated with the pesticide through a Schiff base reaction.
2. The long-acting and sustained-release nano-pesticide formulation according to claim 1, characterized in that: In the amphiphilic polymer, the polymerization group is a group suitable for living radical polymerization reaction.
3. The long-acting and sustained-release nano-pesticide formulation according to claim 1, characterized in that: The to-be-reacted group is an aldehyde group or a ketone.
4. The long-acting and sustained-release nano-pesticide preparation according to claim 1, characterized in that: The adhesion chain unit comprises groups capable of generating a large number of hydrogen bonds; the groups on the adhesion chain unit are hydroxyl groups or carboxyl groups.
5. The long-acting and sustained-release nano-pesticide preparation according to claim 1, characterized in that: The pesticide is an organic pesticide containing primary amine or secondary amine.
6. The long-acting and sustained-release nano-pesticide formulation according to claim 1, wherein: The nano-pesticide formulation has one of the following properties: The average molecular weight of the amphiphilic polymer is 10,000-100,000; The hydrated particle size of the nano-pesticide dispersed in water is between 10-1000 nm; The loading rate of the nano-pesticide is between 0.1-50%; The longest effective sustained-release time of the nano-pesticide is 7-40 days.
7. The long-acting and sustained-release nano-pesticide formulation according to claim 1, characterized in that: The hydrophilic monomer is oligo (ethylene glycol) methyl ether methacrylate (OEGMA), the adhesion monomer is methyl methacrylate (MMA), the hydrophobic monomer is n-butyl methacrylate (nBMA), the modified chain unit is 4-oxobutyl 2-methylacrylate (OBMA), and the organic pesticide is emamectin benzoate.
8. The long-acting and sustained-release nano-pesticide formulation according to claim 1, wherein: The molecular formula of the amphiphilic polymer is P-(OEGMA 40-50 -co-MMA 10-20 )-b-(nBMA 25-35 -co-(MA-EB)); where OEGMA is oligoethylene glycol methacrylate, MMA is methacrylic acid, nBMA is n-butyl methacrylate, and MA-EB is a functional linker conjugated with emamectin benzoate.
9. The long-acting and sustained-release nano-pesticide formulation according to claim 7, characterized in that: The molecular formula of the amphiphilic polymer is P-(OEGMA 40 -co-MMA 10 )-b-(nBMA 30 -co-(MA-EB)), the molecular formula is P-(OEGMA 50 -co-MMA 15 )-b-(nBMA 35 -co-(MA-EB)), or the molecular formula is P-(OEGMA 50 -co-MMA 20 )-b-(nBMA 25 -co-(MA-EB)).
10. Use of the nano-pesticide formulation according to any one of claims 1-9 in pest control.