CN117296833A - Non-systemic pesticide nanogel suspending agent capable of conducting upwards and preparation method thereof - Google Patents

Abstract

The invention relates to a non-systemic pesticide nanogel suspending agent capable of conducting upwards and a preparation method thereof. The nanogel suspending agent consists of pesticide microspheres and a dispersing agent, and compared with non-systemic pesticide microemulsion at the same concentration, the nanogel suspending agent can increase the upward conduction effect by 6.9 times and improve the foliar enrichment concentration by 30%. In addition, the invention can be expanded to a plurality of pesticide carrying systems of non-systemic pesticides, bactericides and plant growth regulators, can well realize upward conduction of the non-systemic pesticides in crops, and provides new theory and technology for improving the pesticide utilization rate.

Description

Non-systemic pesticide nanogel suspending agent capable of conducting upwards and preparation method thereof

Technical Field

The invention relates to the field of pesticide preparations, in particular to a non-systemic pesticide nanogel suspending agent capable of being conducted upwards and a preparation method thereof.

Background

Pesticides are widely used for controlling the diseases, the insect pests and the weeds in agriculture, and the grain production requirement which is increased along with the increase of global population is ensured. Recent data indicate that approximately 30 million kilograms of pesticides are needed annually worldwide in order to reduce the harm and economic loss of diseased cordyceps sinensis. However, most pesticides cannot reach the target site due to unavoidable drift, splash, roll-off, volatilization, degradation, etc., during the pesticide application process, which not only reduces the utilization rate of the pesticide, but also leaves it in the environment, causing serious environmental impact. It is reported that contamination of two or more pesticidal active ingredients will place about 64% of the agricultural land worldwide at a risk of contamination, and 31% of the land is therefore at a high risk of contamination. Therefore, how to improve the pesticide delivery efficiency and reduce the pesticide dosage has become urgent in the agricultural field.

Increasing the probability of contact of the pesticide with the target is an important strategy to increase the pesticide utilization. Recently, prevention of above-ground pests by soil application has come into the field of view. Compared with foliar spraying, most of the main factors causing pesticide loss, such as spray drift, splashing, rolling, volatilization and the like, can be avoided by soil application. In addition, the pesticide can be applied to the soil in higher concentration, so that the pesticide is convenient for crops to continuously absorb, the duration of the pesticide is prolonged, and the investment of labor force can be reduced to a certain extent. Meanwhile, as the active ingredients are hardly diffused in the air, the soil application can reduce the influence of the pesticide on beneficial organisms such as bees, spiders, ladybirds and the like, and the soil application is more environment-friendly.

During the soil application process, the absorption and migration of pesticides in the soil are critical to the final control efficiency, which is generally affected by factors such as the physicochemical properties of the active ingredient, the plant species, the water content of the soil, and the adsorption of organic matter. Among them, the physicochemical properties of the active ingredient itself are one of the prominent factors affecting soil application. In general, pesticides can be classified into systemic pesticides and non-systemic pesticides according to their different absorption and transmission behaviors in plants. For systemic pesticides such as neonicotinoids, they can penetrate into the plant root after contact with the plant root system and reach various parts of the plant with water circulation. The even distribution in the plant body improves the contact probability of the active ingredient and the target and reduces the waste of pesticides. However, for non-systemic pesticides, due to their high octanol-water distribution coefficient, etc., they cannot be conducted upwards after being absorbed by plant roots, resulting in their inability to be applied in soil to control above-ground pests, greatly limiting the application of non-systemic pesticides. At present, new systemic pesticides are required to be continuously developed to meet the requirements of soil application, prevention and control. However, it is quite difficult to develop a new pesticide, not only a lot of manpower and material resources are required, but also it takes years or even decades from synthesis to industrial production and formulation, which is a time-consuming and laborious process.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a non-systemic pesticide nanogel suspending agent capable of conducting upwards, which enables the non-systemic pesticide to be conducted upwards to all tissues of plants after being absorbed by roots through synthesizing a pesticide-carrying nanogel with hydrophobic inside and hydrophilic surface, so as to increase the retention of the non-systemic pesticide in the plants and prolong the duration of the non-systemic pesticide.

In order to achieve the above purpose, the invention adopts the following technical scheme:

the non-systemic pesticide nanogel suspending agent capable of being conducted upwards is characterized by comprising pesticide microspheres and a dispersing agent; the pesticide microsphere consists of a carrier and pesticide active ingredients, and the dispersing agent consists of a surfactant and water.

The pesticide active ingredient is 0.2-2.5% by weight, the carrier is 7.0-7.31% by weight, the surfactant is 28.0-29.3% by weight, and the balance is water.

On the basis of the above-mentioned scheme,

the average particle diameter of the pesticide microsphere is 17-60nm;

the pesticide active ingredient is one or the combination of a plurality of the following preparations;

a bactericide: comprises tebuconazole, chlorothalonil, pyrrolomycin, pyraclostrobin and prochloraz;

and (3) an insecticide: comprises bifenthrin, metaflumizone, high-efficiency cyhalothrin and abamectin;

herbicide: comprises weeding ether, pretilachlor, fomesafen and fluoroglycofen-ethyl.

On the basis of the above-mentioned scheme,

the carrier is random copolymer of octyl acrylate, N-vinyl caprolactam and methoxy polyethylene glycol acrylate.

The invention also aims to provide a preparation method of the non-systemic pesticide nanogel suspending agent capable of conducting upwards.

In order to achieve the above purpose, the invention adopts the following technical scheme:

the preparation method of the non-systemic pesticide nanogel suspending agent capable of conducting upwards is characterized by comprising the following steps of:

step 1, dissolving pesticide active ingredients in a mixture of octyl acrylate, N-vinyl caprolactam and methoxy polyethylene glycol acrylate to form an oil phase solution;

step 2, adding an initiator into water for dissolution to form aqueous phase solution;

step 3, adding the oil phase solution into the water phase solution, and dripping a surfactant until the system forms microemulsion; removing oxygen in the microemulsion, and heating to react to obtain the nanogel suspension.

On the basis of the above-mentioned scheme,

the proportion of each component in the mixture of the octyl acrylate, the N-vinyl caprolactam and the methoxy polyethylene glycol acrylate in the step 1 is as follows: 32.5-33.8wt% octyl acrylate, 24.0wt% N-vinyl caprolactam and 42.2-43.5wt% methoxypolyethylene glycol acrylate; 2.8-35.7wt% of the mixture;

the initiator in the step 2 is ammonium persulfate;

the surfactant in the step 3 is a mixture of Tween 80 and n-butanol, and the mass ratio of the Tween to the n-butanol is 2:1;

the reaction condition in the step 3 is that the reaction is carried out for 12 hours at 60 ℃.

The non-systemic pesticide nanogel suspending agent capable of being conducted upwards and the preparation method thereof have the beneficial effects that:

1. the preparation method provided by the invention obtains the novel suspending agent with extremely small and stable particle size and has a longer slow release effect.

2. The invention can endow oil-soluble non-systemic pesticides such as high-efficiency cyhalothrin with upward conductivity, is beneficial to expanding the use mode of traditional pesticides, improves the pesticide utilization rate and saves manpower and material resources.

3. The invention can prevent the high-concentration active ingredients from generating root phytotoxicity, is beneficial to protecting the agricultural ecological environment and reduces the negative influence on grain crops.

Drawings

The invention has the following drawings:

FIG. 1 is a graph showing the morphology characterization of a lambda-cyhalothrin nanogel; including the appearance of a non-systemic pesticide nanogel suspension and transmission electron microscopy of the nanogel.

Fig. 2 is a graph showing the release profile of lambda-cyhalothrin nanogels in a dispersed phase methanol: water=4:6 solution.

FIG. 3 is a graph of storage stability analysis of lambda-cyhalothrin nanogels.

FIG. 4 shows the change in appearance of roots of young fava beans after 1,3,5 days of culture with a dilution of lambda-cyhalothrin microemulsion and nanogel suspension.

FIG. 5 is a graph showing the analysis of residual concentrations of lambda-cyhalothrin at the top leaf after 1,3,5 days of incubation of young fava beans with dilutions of lambda-cyhalothrin microemulsion and nanogel suspension.

FIG. 6 is a graph showing residual concentration analysis of lambda-cyhalothrin at roots after 1,3,5 days of broad bean seedlings were cultured using dilutions of lambda-cyhalothrin microemulsion and nanogel suspension.

FIG. 7 is a comparison of calculated results of in vivo efficient cyhalothrin transport factors of broad bean seedlings after 1,3,5 days of culture using dilutions of efficient cyhalothrin microemulsion and nanogel suspension, calculated as leaf efficient cyhalothrin residual concentration divided by root efficient cyhalothrin residual concentration.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

The present invention is further illustrated by the following examples, which are not intended to limit the scope of the invention. The various materials described in this invention are commercially available from public sources.

EXAMPLE 1 2.5% high Performance cyhalothrin nanogel suspension

In the formula, the mixture of the octyl acrylate, the N-vinyl caprolactam and the methoxy polyethylene glycol acrylate comprises the following components in percentage: 33wt% octyl acrylate, 24.0wt% N-vinylcaprolactam and 42.9wt% methoxypolyethylene glycol acrylate; the pesticide active ingredient is 35.7wt% of the mixture.

The 2.5% efficient cyhalothrin nano gel suspending agent is prepared according to the formula, and the preparation steps are as follows:

a. 0.625g of lambda-cyhalothrin is ultrasonically dissolved in a mixed solvent of 0.58g of octyl acrylate, 0.42g of N-vinylcaprolactam and 0.75g of methoxypolyethylene glycol acrylate to form an oil phase solution.

b. 0.021g of ammonium persulfate was dissolved in 15g of water to form an aqueous phase solution.

c. C, adding the water phase solution obtained in the step b into the oil phase solution finally obtained in the step a, and dropwise adding a surfactant in a stirring state until the system forms microemulsion; the resulting microemulsion was purged with nitrogen for 10 minutes to remove oxygen from the system, followed by continuous reaction at 60℃with continuous stirring for 12 hours.

d. And c, cooling the solution obtained in the step c to room temperature to finally obtain the pale yellow transparent 2.5% efficient cyhalothrin nanogel suspending agent.

In the high-efficiency cyhalothrin nanogel suspending agent, the weight ratio of the high-efficiency cyhalothrin is 2.5 percent, the weight ratio of the carrier is 7.0 percent, and the weight ratio of the surfactant is 28.0 percent.

The finally obtained nanogel suspending agent is characterized in four aspects of morphology, release performance, storage stability and upward conduction capability,

FIG. 1 is a representation of the morphology of a high-efficiency cyhalothrin nanogel, including the appearance of the nanogel suspension and its transmission electron microscope representation, with a scale of 200nm.

Firstly, the appearance of the obtained high-efficiency cyhalothrin nanogel suspending agent is observed and the transmission electron microscope is characterized, and the result is shown in figure 1, wherein the suspending agent is in a transparent state due to the extremely small particle size of the nano-microspheres, and the average particle size of the nano-microspheres is 17nm.

Figure 2. Lambda. Cyhalothrin nanogel is a release profile in a dispersed phase methanol: water=4:6 solution. By characterization of the release properties of the lambda-cyhalothrin nanogel suspension, we found that 41.2% was released in the first 96 hours and the remainder was slowly released in the subsequent process. This is due to the fact that the nanogel slows down the diffusion of lambda-cyhalothrin, which is released faster in the initial stage due to the higher concentration difference, while the concentration difference is substantially leveled after 96 hours and the overall release rate is greatly reduced.

FIG. 3 analysis of storage stability performance of the lambda-cyhalothrin nanogel suspension. To test the storage stability of the nanogel formulations, nanogel suspensions were packaged in ampoule bottles and stored at 0±2, 25±2, and 54±2 ℃ for 14 days, respectively. The particle size and distribution of the samples were tested every 2 days. As shown in FIG. 3, the particle size of the nanogel does not change significantly with time under cold storage, normal temperature and hot storage, the average particle size fluctuates between 16 and 21nm, and the PDI value is lower than 0.22, indicating that the nanogel has good storage stability.

FIG. 4 changes in appearance of roots of Vicia faba seedlings after 1,3,5 days of culture with the lambda-cyhalothrin microemulsion and nanogel suspension. The mean particle size of the lambda-cyhalothrin microemulsion is 17nm. As shown in the figure, after 1,3,5 days of culture in the high-efficiency cyhalothrin microemulsion diluent, the roots of the broad bean seedlings are gradually blackened and the growth vigor is weakened; and after the broad bean seedlings are cultured in the high-efficiency cyhalothrin nanogel suspension for 1,3 and 5 days, the roots of the broad bean seedlings still keep healthy, which indicates that the high-efficiency cyhalothrin nanogel can avoid phytotoxicity caused by the enrichment of high-efficiency cyhalothrin at the roots.

FIG. 5 shows the residual concentration of lambda-cyhalothrin at the top leaf after 1,3,5 days of incubation of young fava beans with the lambda-cyhalothrin microemulsion and nanogel suspension.

FIG. 6 residual concentration of lambda-cyhalothrin at root after 1,3,5 days of incubation of young broad bean with lambda-cyhalothrin microemulsion and nanogel suspension.

FIG. 7 shows a comparison of the calculated results of the in vivo efficient cyhalothrin transport factor of young fava beans after 1,3,5 days of cultivation using the dilutions of the efficient cyhalothrin microemulsion and the nanogel suspension, calculated as the leaf efficient cyhalothrin concentration divided by the root efficient cyhalothrin concentration.

Through detection, the lambda-cyhalothrin of the microemulsion treatment group is strongly absorbed by the roots, the lambda-cyhalothrin concentration of the roots reaches 452.8mg/L on the 5 th day, the leaf position is only 35.2mg/L, and the transport factor is only 0.08, so that the uncoated lambda-cyhalothrin has extremely poor upward conduction capability, and the roots of crops can be damaged once the lambda-cyhalothrin is applied at high concentration, thereby causing phytotoxicity. Compared with the nano gel suspending agent treatment group, the concentration of the lambda-cyhalothrin at the root is maintained at about 70mg/L, the concentration of the leaf part is maintained at 46mg/L, and the transfer factor is improved to 0.63, so that the high-efficiency lambda-cyhalothrin coated by the nano gel has upward conduction capability, and the damage of high-concentration liquid medicine to the root of crops can be avoided.

Example 2.5% pyraclostrobin nanogel suspension

In the formula, the mixture of the octyl acrylate, the N-vinyl caprolactam and the methoxy polyethylene glycol acrylate comprises the following components in percentage: 33wt% octyl acrylate, 24.0wt% N-vinylcaprolactam and 42.9wt% methoxypolyethylene glycol acrylate; the pesticide active ingredient is 35.7wt% of the mixture.

2.5% pyraclostrobin nano gel suspending agent is prepared according to the formula. The preparation method comprises the following steps:

a. 0.625g of pyraclostrobin is sonicated in a mixed solvent of 0.58g of octyl acrylate, 0.42g N-vinylcaprolactam and 0.75g of methoxypolyethylene glycol acrylate to form an oil phase solution.

b. 0.021g of ammonium persulfate was dissolved in 15.6g of water to form an aqueous phase solution.

c. C, adding the water phase solution obtained in the step b into the oil phase solution finally obtained in the step a, and dropwise adding a surfactant in a stirring state until the system forms microemulsion; introducing nitrogen into the obtained microemulsion for protection for 10min to remove oxygen in the system, and then continuously reacting for 12h at 60 ℃ under continuous stirring.

d. And c, cooling the solution obtained in the step c to room temperature to finally obtain the pale yellow transparent 2.5% pyraclostrobin nanogel suspending agent.

In the pyraclostrobin nanogel suspension, the pyraclostrobin accounts for 2.5wt% of the total weight of the suspension, the carrier accounts for 7.0wt% of the total weight of the suspension, and the surfactant accounts for 28.0wt% of the total weight of the suspension. The average particle diameter of the nanometer microsphere in the pyraclostrobin nanometer gel suspending agent is 56nm.

Comparing the upward conduction capability of the obtained pyraclostrobin nanogel suspending agent with that of the pyraclostrobin suspending agent, wherein the average particle size of the pyraclostrobin suspending agent is 800nm, and the result is as follows:

table 2.2.5% statistical analysis of upward conduction results for pyraclostrobin nanogel suspension

Example 3 0.2% Avermectin nanogel suspension

In the formula, the mixture of the octyl acrylate, the N-vinyl caprolactam and the methoxy polyethylene glycol acrylate comprises the following components in percentage: 32.5% by weight of octyl acrylate, 24.0% by weight of N-vinylcaprolactam and 43.5% by weight of methoxypolyethylene glycol acrylate; the pesticide active ingredient is 2.8wt% of the mixture.

The 0.2% avermectin nano gel suspending agent is prepared according to the formula. The preparation method comprises the following steps:

a. 0.049g of avermectin is ultrasonically dissolved in a mixed solvent of 0.57g of octyl acrylate, 0.42g of N-vinylcaprolactam and 0.76g of methoxypolyethylene glycol acrylate to form an oil phase solution.

b. 0.024g of ammonium persulfate was dissolved in 15.1g of water to form an aqueous phase solution.

c. C, adding the water phase solution obtained in the step b into the oil phase solution finally obtained in the step a, and dropwise adding a surfactant in a stirring state until the system forms microemulsion; introducing nitrogen into the obtained microemulsion for protection for 10min to remove oxygen in the system, and then continuously reacting for 12h at 60 ℃ under continuous stirring.

d. And c, cooling the solution obtained in the step c to room temperature to finally obtain the pale yellow transparent 2.5% avermectin nanogel suspending agent.

In the avermectin nanogel suspending agent, the avermectin accounts for 0.2wt percent, the carrier accounts for 7.31wt percent, and the surfactant accounts for 29.3wt percent. The average particle diameter of the nanometer microsphere in the obtained avermectin nanometer gel suspending agent is 58nm.

The upward conduction capacity of the obtained avermectin nanogel suspending agent and the avermectin microcapsule suspending agent is compared, the average grain diameter of the microcapsules in the avermectin microcapsule suspending agent is 416nm, and the result is as follows:

table 3.0.2% upward conduction results statistical analysis of avermectin nanogel suspension

EXAMPLE 4 1.8% prochloraz nanogel suspension

In the formula, the mixture of the octyl acrylate, the N-vinyl caprolactam and the methoxy polyethylene glycol acrylate comprises the following components in percentage: 33.8% by weight of octyl acrylate, 24.0% by weight of N-vinylcaprolactam and 42.2% by weight of methoxypolyethylene glycol acrylate; the pesticide active ingredient is 25.4wt% of the mixture.

The prochloraz nano-gel suspending agent with the concentration of 1.8 percent is prepared according to the formula. The preparation method comprises the following steps:

a. prochloraz 0.421g was ultrasonically dissolved in a mixed solvent of octyl acrylate 0.56g, 0.4. 0.4g N-vinylcaprolactam and methoxypolyethylene glycol acrylate 0.7g to form an oil phase solution.

b. 0.022g of ammonium persulfate was dissolved in 14.2g of water to form an aqueous phase solution.

c. C, adding the water phase solution obtained in the step b into the oil phase solution finally obtained in the step a, and dropwise adding a surfactant in a stirring state until the system forms microemulsion; introducing nitrogen into the obtained microemulsion for protection for 10min to remove oxygen in the system, and then continuously reacting for 12h at 60 ℃ under continuous stirring.

d. And c, cooling the solution obtained in the step c to room temperature to finally obtain the pale yellow transparent 1.8% prochloraz nano gel suspending agent.

In the prochloraz nanogel suspending agent, the prochloraz accounts for 1.8 weight percent, the carrier accounts for 7.23 weight percent, and the surfactant accounts for 29.0 weight percent. The average particle diameter of the nano microsphere in the prochloraz nano gel suspending agent is 32nm.

The prochloraz nanogel suspending agent and prochloraz suspending agent obtained by comparison are compared for upward conduction capacity, the average particle size of the prochloraz suspending agent is 632nm, and the result is as follows:

table 4.1.8% statistical analysis of the upward conduction results of prochloraz nanogel suspension

The results of the upward conduction experiments for each of the comparative materials in examples 2-4 demonstrate that the upward conduction capability is greatly reduced when the average particle size of the microparticles exceeds the range of the nanomaterial scale (100 nm).

EXAMPLE 5 2.5% Avermectin-efficient cyhalothrin nanogel suspension

In the formula, the mixture of the octyl acrylate, the N-vinyl caprolactam and the methoxy polyethylene glycol acrylate comprises the following components in percentage: 33wt% octyl acrylate, 24.0wt% N-vinylcaprolactam and 42.9wt% methoxypolyethylene glycol acrylate; the pesticide active ingredient is 35.7wt% of the mixture.

The 2.5% avermectin and high-efficiency cyhalothrin nano gel suspending agent is prepared according to the formula, and the preparation steps are as follows:

a. 0.31g of lambda-cyhalothrin and 0.31g of avermectin are ultrasonically dissolved in a mixed solvent of 0.58g of octyl acrylate, 0.42g N-vinyl caprolactam and 0.75g of methoxy polyethylene glycol acrylate to form an oil phase solution.

b. 0.021g of ammonium persulfate was dissolved in 15.6g of water to form an aqueous phase solution.

c. C, adding the water phase solution obtained in the step b into the oil phase solution finally obtained in the step a, and dropwise adding a surfactant in a stirring state until the system forms microemulsion; introducing nitrogen into the obtained microemulsion for protection for 10min to remove oxygen in the system, and then continuously reacting for 12h at 60 ℃ under continuous stirring.

d. And c, cooling the solution obtained in the step c to room temperature to finally obtain the pale yellow transparent 2.5% abamectin and high-efficiency cyhalothrin nanogel suspending agent.

In the avermectin and high-efficiency cyhalothrin nanogel suspending agent, the avermectin accounts for 1.25wt%, the high-efficiency cyhalothrin accounts for 1.25wt%, the carrier accounts for 7.06wt% and the surfactant accounts for 28.2wt%. The average grain diameter of the nanometer microsphere in the obtained avermectin and high-efficiency cyhalothrin nanometer gel suspending agent is 60nm.

The upward conduction capacity of the obtained avermectin and high-efficiency cyhalothrin nano-gel suspending agent and the avermectin and high-efficiency cyhalothrin microemulsion is compared, the average grain diameter of the avermectin and high-efficiency cyhalothrin microemulsion is 38nm, and the result is as follows:

TABLE 5.2.5% Avermectin-high efficiency cyhalothrin nanogel suspension

Table 5 above shows that: if the active ingredient is not coated by the carrier material, it is only released in the oil phase solvent in a dissolved state, and even if the average particle size is smaller than that of the nano-microspheres in the nano-gel suspending agent, the systemic effect is poor.

EXAMPLE 6 2.5% high Performance cyhalothrin nanogel suspension

In the formula, the mixture of the octyl acrylate, the N-vinyl caprolactam and the methoxy polyethylene glycol acrylate comprises the following components in percentage: 33wt% octyl acrylate, 24.0wt% N-vinylcaprolactam and 42.9wt% methoxypolyethylene glycol acrylate; the pesticide active ingredient is 35.7wt% of the mixture.

The 2.5% efficient cyhalothrin nano gel suspending agent is prepared according to the formula, and the preparation steps are as follows:

a. 0.62g of lambda-cyhalothrin is ultrasonically dissolved in a mixed solvent of 0.58g of octyl acrylate, 0.42g N-vinylcaprolactam and 0.75g of methoxypolyethylene glycol acrylate to form an oil phase solution.

b. 0.021g of ammonium persulfate was dissolved in 15.6g of water to form an aqueous phase solution.

c. C, adding the water phase solution obtained in the step b into the oil phase solution finally obtained in the step a, and dropwise adding a surfactant in a stirring state until the system forms microemulsion; introducing nitrogen into the obtained microemulsion for protection for 10min to remove oxygen in the system, and then continuously reacting for 12h at 60 ℃ under continuous stirring.

d. And c, cooling the solution obtained in the step c to room temperature to finally obtain the cloudy and yellow 2.5% efficient cyhalothrin nanogel suspending agent.

In the high-efficiency cyhalothrin nanogel suspending agent, the weight ratio of the high-efficiency cyhalothrin is 2.5 percent, the weight ratio of the carrier is 7.06 percent, and the weight ratio of the surfactant is 16.1 percent. The average particle diameter of the nanometer microsphere in the obtained high-efficiency cyhalothrin nanometer gel suspending agent is 960nm.

EXAMPLE 7 2.5% Avermectin nanogel suspension

In the formula, the mixture of the octyl acrylate, the N-vinyl caprolactam and the methoxy polyethylene glycol acrylate comprises the following components in percentage: 28.1% by weight of octyl acrylate, 23.7% by weight of N-vinylcaprolactam and 48.2% by weight of methoxypolyethylene glycol acrylate; the pesticide active ingredient is 45.9wt% of the mixture.

The 2.5% avermectin nano gel suspending agent is prepared according to the formula. The preparation method comprises the following steps:

a. 0.62g of avermectin is ultrasonically dissolved in a mixed solvent of 0.38g of octyl acrylate, 0.32. 0.32g N-vinyl caprolactam and 0.65g of methoxy polyethylene glycol acrylate to form an oil phase solution.

b. 0.024g of ammonium persulfate was dissolved in 15.5g of water to form an aqueous phase solution.

c. C, adding the water phase solution obtained in the step b into the oil phase solution finally obtained in the step a, and dropwise adding a surfactant in a stirring state until the system forms microemulsion; introducing nitrogen into the obtained microemulsion for protection for 10min to remove oxygen in the system, and then continuously reacting for 12h at 60 ℃ under continuous stirring.

d. And c, cooling the solution obtained in the step c to room temperature to finally obtain the pale yellow turbid 2.5% avermectin nanogel suspending agent, wherein a large amount of precipitate particles are arranged at the bottom.

In the avermectin nanogel suspending agent, the avermectin accounts for 2.5wt percent, the carrier accounts for 5.51wt percent, and the surfactant accounts for 28.6wt percent. The average particle diameter of the precipitated particles in the obtained avermectin nanogel suspending agent is 2.41 mu m, exceeds the nanometer level, and cannot be suspended in water.

The experimental results of the modified raw material proportioning in examples 6-7 show that the nano-microspheres with the target particle size range cannot be obtained after the range of the fixed raw material proportioning is exceeded.

The above-mentioned examples 1 to 5 are all possible in which the active ingredient of the pesticide is replaced with a plurality of non-systemic insecticides, fungicides, herbicides, etc. which have a high oil-water partition coefficient and are hardly soluble in water, or a combination of any two or more of these agents. The preparation comprises the following components: tebuconazole, chlorothalonil, pyrrolomycin, pyraclostrobin and prochloraz (bactericide); bifenthrin, metaflumizone, lambda-cyhalothrin, abamectin (insecticide); herbicidal ethers, pretilachlor, fomesafen, fluoroglycofen-ethyl (herbicides), and the like.

The various embodiments provided by the invention can be combined with each other in any way as required, and the technical scheme obtained by the combination is also within the scope of the invention. It will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the spirit or scope of the invention. Thus, the present invention also includes such modifications and variations provided they come within the scope of the claims and their equivalents.

What is not described in detail in this specification is prior art known to those skilled in the art.

Claims (5)

1. The non-systemic pesticide nanogel suspending agent capable of being conducted upwards is characterized by comprising pesticide microspheres and a dispersing agent; the pesticide microsphere consists of a carrier and pesticide active ingredients, and the dispersing agent consists of a surfactant and water.

The pesticide active ingredient is 0.2-2.5% by weight, the carrier is 7.0-7.31% by weight, the surfactant is 28.0-29.3% by weight, and the balance is water.

2. The upward-conductive, non-systemic pesticide nanogel suspension of claim 1, wherein:

the average particle diameter of the pesticide microsphere is 17-60nm;

the pesticide active ingredient is one or the combination of a plurality of the following preparations;

a bactericide: comprises tebuconazole, chlorothalonil, pyrrolomycin, pyraclostrobin and prochloraz;

and (3) an insecticide: comprises bifenthrin, metaflumizone, high-efficiency cyhalothrin and abamectin;

herbicide: comprises weeding ether, pretilachlor, fomesafen and fluoroglycofen-ethyl.

3. The upward-conducting non-systemic pesticide nanogel suspension according to claim 1, wherein the carrier is a random copolymer of octyl acrylate, N-vinyl caprolactam, methoxypolyethylene glycol acrylate.

4. A method for preparing the upwardly conductive non-systemic pesticide nanogel suspension according to any one of claims 1 to 3, comprising the steps of:

step 1, dissolving pesticide active ingredients in a mixture of octyl acrylate, N-vinyl caprolactam and methoxy polyethylene glycol acrylate to form an oil phase solution;

step 2, adding an initiator into water for dissolution to form aqueous phase solution;

step 3, adding the oil phase solution into the water phase solution, and dripping a surfactant until the system forms microemulsion; removing oxygen in the microemulsion, and heating to react to obtain the nanogel suspension.

5. The method for preparing the non-systemic pesticide nanogel suspending agent capable of being conducted upwards as claimed in claim 4, wherein the method comprises the following steps of:

the proportion of each component in the mixture of the octyl acrylate, the N-vinyl caprolactam and the methoxy polyethylene glycol acrylate in the step 1 is as follows: 32.5-33.8wt% octyl acrylate, 24.0wt% N-vinyl caprolactam and 42.2-43.5wt% methoxypolyethylene glycol acrylate; 2.8-35.7wt% of the mixture;

the initiator in the step 2 is ammonium persulfate;

the surfactant in the step 3 is a mixture of tween 80 and n-butanol, and the mass ratio of tween to n-butanol is 2:1, a step of;

the reaction condition in the step 3 is that the reaction is carried out for 12 hours at 60 ℃.