Application of bis-imidazolyl polyionic liquid functionalized hydrothermal carbon in preparation of pesticide sustained-release agent

Abstract

A preparation method of the functionalized hydrothermal carbon comprises the following steps: carrying out carbonization reaction on bamboo powder and a hydrochloric acid solution by adopting a hydrothermal carbonization method, adding alkali liquor into a product obtained by the reaction, stirring, filtering, washing with water until filtrate is neutral, and drying to obtain the functionalized hydrothermal carbon. Hydrothermal bamboo charcoal is obtained; the preparation method comprises the following steps: putting dichloromethane and 1-vinyl imidazole into a reaction kettle to react, and obtaining a monomer N, N '-methylene-bis (1-(3-vinyl imidazole)) chlorine (DVim-Cl) after the reaction is completed; taking the hydrothermal bamboo charcoal and DVim-Cl, adding an initiator and a solvent, and putting the mixture into a reaction kettle for heating reaction to obtain a target compound. The prepared sustained-release agent can effectively load herbicides, has good herbicidal activity, the maximum loading capacity can reach 565 mg / g, the loading rate reaches 36.1%, and the sustained-release agent has good application prospects in the field of pesticide sustained release.

Description

Technical Field

[0001] The invention relates to an application of functionalized hydrothermal carbon, and in particular to an application of bisimidazolyl polyionic liquid functionalized hydrothermal carbon in the preparation of a pesticide slow-release agent. Background Art

[0002] The widespread use of pesticides in agriculture to control pests, fungi and weeds has had a serious negative impact on both the ecological balance system and public health. Therefore, more effective and safer methods of pesticide application are needed to solve these problems. After the pesticide is released, the efficacy of traditional pesticide formulations will decrease rapidly, causing serious harm to the environment. For example, emulsifiable concentrates will lead to the use of a large amount of benzene solvents, while the use of dust and wettable powders will produce dust pollution. These formulations will pollute the environment and harm the health of the applicators after use. In addition, due to their short duration, the amount of application and frequency of use need to be increased, resulting in increased production costs and increased pesticide residues. They will also cause pests to develop resistance and shorten the service life of pesticides. Therefore, appropriate application methods must be used to prevent pesticide pollution. An effective method is to develop controlled release formulations (CRFs) of pesticides, which has received increasing attention in recent years. CRFs can keep pesticides above effective levels for a long time, which will help reduce the consumption rate of herbicides and increase their biological activity.

[0003] Adsorption-type slow-release agent refers to a pesticide formulation obtained by using an adsorption carrier as a storage body for the pesticide. The herbicide is adsorbed on the carrier, which can avoid the unnecessary loss of highly water-soluble herbicides such as 2,4-D Na, while encapsulating it in a suitable carrier can increase the effectiveness of the active ingredient and improve its light stability. Therefore, how to develop an efficient adsorption-type slow-release agent is a technical problem that needs to be solved urgently. Summary of the invention

[0004] Purpose of the invention: The present invention aims to provide an application of a bisimidazolyl polyionic liquid hydrothermal carbon in the preparation of a pesticide sustained-release agent, wherein the functionalized hydrothermal carbon can improve the weed control efficiency and reduce the side effects of pesticides during the pesticide sustained-release process.

[0005] Technical solution: The application of the bisimidazolyl polyionic liquid functionalized hydrothermal carbon in the preparation of a pesticide sustained-release agent according to the present invention, and the preparation method of the bisimidazolyl polyionic liquid functionalized hydrothermal carbon comprises the following steps:

[0006] (1) using a hydrothermal carbonization method to carbonize bamboo powder and a hydrochloric acid solution, adding an alkali solution to the reaction product, stirring, filtering and washing with water until the filtrate is neutral, thereby obtaining hydrothermal bamboo charcoal;

[0007] Dichloromethane and 1-vinylimidazole were placed in a reaction kettle for reaction. After the reaction was completed, the mixture was filtered to obtain the monomer N,N'-methylene-bis(1-(3-vinylimidazole)) chloride (DVim-Cl).

[0008] (2) Take the above hydrothermal bamboo charcoal and DVim-Cl, add an initiator and a solvent, put them into a reactor and heat them for reaction to obtain the product bisimidazolyl polyionic liquid functionalized hydrothermal charcoal.

[0009] The synthetic route of the above reaction is as follows:

[0010]

[0011] Furthermore, in step (1), the concentration of the bamboo powder in the hydrochloric acid solution is 0.2-0.3 g / mL, and the concentration of the hydrochloric acid is 0.5-1.0 mol / L.

[0012] Furthermore, the reaction temperature of the carbonization reaction in step (1) is 200-220° C., the carbonization time is 12-24 hours, and the alkali solution stirring time is 2-4 hours; the alkali solution is a sodium hydroxide solution with a concentration of 0.2-0.25 mol / L.

[0013] Furthermore, in step (1), the molar ratio of dichloromethane to 1-vinylimidazole is 1-3:2-4, the reaction temperature is 100-120° C., and the reaction time is 12-80 h.

[0014] Furthermore, when synthesizing the N,N'-methylene-bis(1-(3-vinylimidazole)) chloride monomer, a low-temperature solvent-free method can be selected for preparation, or an additional solvent (such as tetrahydrofuran, acetonitrile, etc.) can be added in addition to the two raw materials for preparation; among them, the low-temperature solvent-free method is preferably used to synthesize the N,N'-methylene-bis(1-(3-vinylimidazole)) chloride monomer, which can achieve green environmental protection, improve reaction efficiency, and reduce production costs.

[0015] Furthermore, in step (2), the mass ratio of the hydrothermal carbon, DVim-Cl and initiator is 10-12:15-25:1.4-2.5.

[0016] Furthermore, the solvent in step (2) is a mixed solvent of water and dimethyl sulfoxide, and the volume ratio of water to dimethyl sulfoxide is 1-2:1-2.

[0017] Furthermore, after the reaction in step (2) is completed, the product is first filtered, then washed with anhydrous ethyl acetate, and the filter residue is dried to obtain the target compound.

[0018] Furthermore, the drying temperature is 60-80°C.

[0019] Furthermore, the pesticide sustained-release agent comprises bisimidazolyl polyionic liquid functionalized hydrothermal carbon, the bisimidazolyl polyionic liquid functionalized hydrothermal carbon is a pesticide carrier, and the pesticide is 2,4-D sodium.

[0020] Furthermore, the pesticide slow-release agent includes Cl - Salts such as iodine are used to adjust the sustained-release rate of pesticides.

[0021] Furthermore, the pesticide sustained-release agent can also be controllably released by adjusting the pH, pH=5-7.

[0022] Principle of the invention: The surface of hydrochar contains abundant functional groups such as hydroxyl and carboxyl. Introducing nitrogen-containing groups into the surface of hydrochar can change the surface potential and polarity of hydrochar, resulting in the sustained-release agent being positively charged and hydrophilic, thereby improving the adsorption and loading capacity of modified hydrochar for anionic pesticides through electrostatic interaction. The present invention uses azobisisobutyronitrile as an initiator, and initiates N,N'-methylene-bis(1-(3-vinylimidazole)) chloride graft copolymerization on the surface of hydrochar to prepare poly(N,N'-methylene-bis(1-(3-vinylimidazole)) chloride) functionalized hydrochar by low-temperature solvent thermal method, and obtains a bisimidazolyl polyionic liquid functionalized hydrochar carrier. The Zeta potential of the carrier surface of the bisimidazolyl polyionic liquid functionalized hydrochar changes significantly with the change of solution pH, and the electrostatic and other forces between the carrier and the pesticide 2,4-D Na are affected by the change of environmental pH and ionic strength, thereby giving the pesticide sustained-release agent multiple stimulus responsiveness to pH and ionic strength. The controlled release of pesticide slow-release agents can be achieved by controlling the pH or ionic strength of the environment.

[0023] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: (1) The N,N'-methylene-bis(1-(3-vinylimidazole)) chloride monomer is synthesized by a low-temperature solvent-free method, which is green and environmentally friendly, improves reaction efficiency, and reduces production costs; (2) The sustained-release agent has stable performance, and the low-temperature solvent thermal method is used to synthesize the bisimidazolyl polyionic liquid functionalized hydrothermal carbon, which shows a loading amount of up to 565 mg / g for the pesticide 2,4-D Na, and the loading rate reaches more than 36%; (3) The sustained-release agent can regulate the drug release rate by changing the pH and ionic strength, prolong the drug efficacy, and the duration can reach more than 35 hours, which can improve the utilization efficiency of the herbicide; (4) The carrier raw material is waste biomass, which has a wide source and low price. The method for preparing hydrothermal bamboo charcoal is a hydrothermal method. The reaction process is carried out under closed conditions and is environmentally friendly; (5) The preparation method and equipment of the sustained-release agent are simple, and it is expected to be widely used in the agricultural field. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1FTIR spectra of hydrothermal bamboo charcoal (HC), bisimidazolyl polyionic liquid functionalized hydrothermal bamboo charcoal sustained-release carrier (BIPIL-HC), N,N'-methylene-bis(1-(3-vinylimidazole)) chloride (DVim-Cl), bisimidazolyl polyionic liquid functionalized hydrothermal charcoal pesticide sustained-release agent (BIPIL-HC-2,4-D Na) and pesticide 2,4-D Na;

[0025] Figure 2 The loading capacity of BIPIL-HC for different initial concentrations of 2,4-D Na;

[0026] Figure 3 Zeta potential of BIPIL-HC and its loading capacity for 2,4-D Na at different pH values;

[0027] Figure 4 Figure 2 is a study on the sustained release behavior of BIPIL-HC-2,4-D Na in different solutions; wherein, a) is a sustained release graph of BIPIL-HC-2,4-D Na at different pH values, and b) is a sustained release graph of BIPIL-HC-2,4-D Na in a saline solution;

[0028] Figure 5 This is a diagram showing the herbicidal activity study of BIPIL-HC-2,4-D Na. DETAILED DESCRIPTION

[0029] The technical solution of the present invention is further described below in conjunction with the accompanying drawings.

[0030] Example 1

[0031] The preparation method of the bisimidazolyl polyionic liquid functionalized hydrothermal carbon pesticide sustained-release agent is as follows:

[0032] Weigh 40 g of bamboo powder into a 500 mL high-pressure reactor lined with polytetrafluoroethylene, add 160 mL of 1 mol / L hydrochloric acid solution, stir evenly, react at 200 ° C for 24 h, cool, filter, wash with deionized water, filter, add 400 mL of 0.2 mol / L sodium hydroxide solution and stir for 2 h, cool, filter, wash with deionized water until the filtrate reaches a stable pH value, filter, and dry at 60 ° C to obtain hydrothermal bamboo charcoal (HC);

[0033] 9.41 g of 1-vinylimidazole and 6.37 g of dichloromethane were weighed and mixed evenly in a 100 mL high-pressure reactor lined with polytetrafluoroethylene. After reacting at 100° C. for 72 h, the mixture was cooled and filtered to obtain the monomer N,N′-methylene-bis(1-(3-vinylimidazole) chloride) (DVim-Cl).

[0034] 1 g of hydrothermal bamboo charcoal, 2.5 g of DVim-Cl, 0.25 g of azobisisobutyronitrile, and 10 ml of a mixed solution of deionized water and dimethyl sulfoxide were weighed separately with a solution volume ratio of 1:1, poured into a 100 mL high-pressure reactor lined with polytetrafluoroethylene, heated at 100 °C for 24 h, and after cooling to room temperature, filtered and washed with deionized water until neutral, and the obtained sample was dried in an oven at 60 °C to obtain a bisimidazolyl polyionic liquid functionalized hydrothermal charcoal pesticide sustained-release carrier (BIPIL-HC).

[0035] Example 2

[0036] The preparation method of the bisimidazolyl polyionic liquid functionalized hydrothermal carbon pesticide sustained-release agent is as follows:

[0037] Weigh 40 g of bamboo powder into a 500 mL high-pressure reactor lined with polytetrafluoroethylene, add 180 mL of 1 mol / L hydrochloric acid solution, stir evenly, react at 200 ° C for 24 h, cool, filter, wash with deionized water, filter, add 400 mL of 0.2 mol / L sodium hydroxide solution and stir for 2 h, cool, filter, wash with deionized water until the filtrate reaches a stable pH value, filter, and dry at 60 ° C to obtain hydrothermal bamboo charcoal (HC);

[0038] Weigh 9.41 g of 1-vinylimidazole and 6.37 g of dichloromethane in a 100 mL polytetrafluoroethylene-lined autoclave and stir evenly. After reacting at 100° C. for 72 h, cool, filter, and wash with anhydrous ethyl acetate to obtain the monomer N,N'-methylene-bis(1-(3-vinylimidazole) chloride) (DVim-Cl).

[0039] 1 g of hydrothermal bamboo charcoal, 2 g of DVim-Cl, 0.14 g of azobisisobutyronitrile, and 10 ml of a mixed solution of deionized water and dimethyl sulfoxide were weighed respectively, with a solution volume ratio of 1:1, poured into a 100 mL high-pressure reactor lined with polytetrafluoroethylene, heated at 100 °C for 24 h, and after cooling to room temperature, filtered and washed with deionized water until neutral, and the obtained sample was dried in an oven at 60 °C to obtain a bisimidazolyl polyionic liquid functionalized hydrothermal charcoal pesticide sustained-release carrier (BIPIL-HC).

[0040] Example 3

[0041] The preparation method of the bisimidazolyl polyionic liquid functionalized hydrothermal carbon pesticide sustained-release agent is as follows:

[0042] Weigh 40 g of bamboo powder into a 500 mL high-pressure reactor lined with polytetrafluoroethylene, add 200 mL of 1 mol / L hydrochloric acid solution, stir evenly, react at 200 ° C for 24 h, cool, filter, wash with deionized water, filter, add 400 mL of 0.2 mol / L sodium hydroxide solution and stir for 2 h, cool, filter, wash with deionized water until the filtrate reaches a stable pH value, filter, and dry at 60 ° C to obtain hydrothermal bamboo charcoal (HC);

[0043] 9.41 g of 1-vinylimidazole and 6.37 g of dichloromethane were weighed and mixed evenly in a 100 mL high-pressure reactor lined with polytetrafluoroethylene. After reacting at 100° C. for 72 h, the mixture was cooled, filtered, and washed with anhydrous ethyl acetate to obtain the monomer N,N'-methylene-bis(1-(3-vinylimidazole)) chloride (DVim-Cl).

[0044] 1 g of hydrothermal bamboo charcoal, 2.5 g of DVim-Cl, 0.25 g of azobisisobutyronitrile, and 20 ml of a mixed solution of deionized water and dimethyl sulfoxide were weighed respectively, with a solution volume ratio of 1:1, poured into a 100 mL high-pressure reactor lined with polytetrafluoroethylene, heated at 100 °C for 24 h, and after cooling to room temperature, filtered and washed with deionized water until neutral, and the obtained sample was dried in an oven at 60 °C to obtain a bisimidazolyl polyionic liquid functionalized hydrothermal charcoal pesticide sustained-release carrier (BIPIL-HC).

[0045] The following is a structural characterization and test result analysis of the bisimidazolyl polyionic liquid functionalized hydrothermal carbon pesticide sustained-release agent prepared in Example 1.

[0046] (1) FTIR

[0047] The hydrothermal bamboo charcoal and its samples before and after modification, before and after loading pesticides were characterized by infrared spectroscopy. Figure 1 . The step of preparing a sustained-release agent by loading pesticides on hydrothermal bamboo charcoal is as follows: weigh 0.40 g of the hydrothermal bamboo charcoal pesticide sustained-release carrier in Example 1 into a conical flask and add 500 ml of a 500 mg / L 2,4-D Na solution, shake in an oscillator at 100 rpm for 12 hours, filter, and dry to obtain a 2,4-D Na sustained-release agent (BIPIL-HC-2,4-D Na). The curves in the figure represent: hydrothermal bamboo charcoal (HC), N,N'-methylene-bis(1-(3-vinylimidazole)) chloride (DVim-Cl), bisimidazolyl polyionic liquid functionalized hydrothermal charcoal pesticide sustained-release carrier (BIPIL-HC), bisimidazolyl polyionic liquid functionalized hydrothermal charcoal pesticide sustained-release agent (BIPIL-HC-2,4-D Na) and pesticide 2,4-D Na.

[0048] HC at 3406, 2958, 1689, 1614 and 1384 cm–1 The characteristic peaks at represent the stretching vibrations of O–H, aliphatic C–H, C=O and C=C, and the bending vibrations of methylene, respectively.

[0049] DVim-Cl at 1648, 1561 and 1172 cm –1 The characteristic peaks at 935cm are the C=N, C=C and C–N stretching vibrations of imidazole. –1 The peak at 935 cm is the C–H bending vibration peak of vinyl. After HC modification, the peak changed significantly. The characteristic peak of imidazole appeared on the surface of BIPIL-HC at 935 cm –1 The C–H bending vibration peak of the vinyl group disappeared, confirming that the vinyl group participated in the cross-linking polymerization.

[0050] 2,4-D Na at 1620, 1481, 1337, 1038 and 795 cm –1 The characteristic peaks at the bottom of the graph are the stretching vibration of C=C on the aromatic ring, the plane bending vibration of C–H, the stretching vibration of carboxylate, C–O–C, and C–Cl. After loading with 2,4-D Na, the characteristic peaks red-shift to 1613, 1346, and 805 cm –1 . It showed that 2,4-D Na was loaded on BIPIL-HC.

[0051] (2) Effect of initial concentration on adsorption

[0052] 40 mg of BIPIL-HC and 50 mL of 2,4-D Na solution (25, 50, 100, 200, 300, 400, 500, 600, 700, 800, 900 mg / L, T = 298 K, pH = 5) were oscillated for 12 h, and the loading amount at different initial concentrations was measured and calculated.

[0053] Figure 2 This is the effect of initial concentration on the loading of 2,4-D Na on BIPIL-HC. As can be seen from the figure, with the increase of concentration, the loading amount of 2,4-D Na increases significantly. At 298K, with the initial concentration increasing from 25 mg / L to 900 mg / L, the loading amount increases from 28.35 mg / g to 565.10 mg / g.

[0054] (3) Zeta potential of BIPIL-HC and its loading capacity for 2,4-D Na at different pH values

[0055] The Zeta potential of BIPIL-HC varies from +35.2 eV to -3.17 eV in the pH range of 2 to 12. PZC ) is around 11.5. Figure 3As shown, when pH < 11.5, BIPIL-HC presents a positive charge, and vice versa. PZC The results showed that BIPIL-HC can load the pesticide 2,4-D Na in a wide pH range. When the pH value of the solution was in the range of 4 to 9, it showed a higher loading capacity for 2,4-D Na.

[0056] (4) Effects of different environmental conditions on the sustained-release behavior of BIPIL-HC-2,4-D Na sustained-release agent

[0057] The sustained release of BIPIL-HC-2,4-D Na was studied. 40.0 mg BIPIL-HC-2,4-D Na (2,4-D Na loading rate 36.1%) was weighed and added to a dialysis bag with a molecular weight cutoff of 8000 g / mol. The dialysis bag was placed in a 250 ml beaker, and 150 ml of different pH sustained release solutions (pH = 5.0, 7.0 and 9.0, adjusted by 0.1 M NaOH and 0.1 M HCl) or salt solution (0.02 M NaCl, pH is about 7.0) were added. The mixture was shaken at 100 rpm in an oscillator at room temperature. 5 ml of supernatant was taken at a certain time interval, and 5 ml of the same solution was added at the same time. Subsequently, the filtrate was tested for the concentration of 2.4-D at a wavelength of 229.5 nm by UV-visible spectrophotometer and its cumulative release rate was calculated according to the formula.

[0058] Depend on Figure 4 a) It can be seen that the cumulative release rate of 2,4-D Na in BIPIL-HC-2,4-D Na sustained-release agent increases gradually with time under different pH conditions. The sustained-release rate is 23.09% to 31.09% after 35 hours under the condition of pH = 5.0 to 7.0, and the sustained-release rate is 85.10% after 35 hours under the condition of pH = 9.0. The release is faster in pH = 9.0 than in pH = 5.0 to 7.0. Figure 4 a) It can be seen that the pH of the solution has a great influence on the sustained release ability of BIPIL-HC-2,4-D Na.

[0059] Depend on Figure 4b) It can be seen that the effect of ionic strength on the release performance was studied using 0.02M NaCl solution and water as controls as release media. The release rate of BIPIL-HC-2,4-D Na under 0.02M NaCl was significantly different from that when deionized water was used as the release medium. The cumulative release rate using 0.02M NaCl as the release medium reached equilibrium after 34 hours, while the cumulative release rate using deionized water as the release medium was only 22% after 34 hours. Therefore, ionic strength significantly affects the release rate of BIPIL-HC-2,4-D Na. The release of BIPIL-HC-2,4-D Na showed obvious dual pH and ionic strength response characteristics.

[0060] (5) Herbicidal activity

[0061] Weigh 0.40 g of the above hydrothermal charcoal pesticide sustained-release carrier into a conical flask and add 500 ml of 500 mg / L 2,4-D Na solution. Oscillate in an oscillator at 100 rpm for 12 h, filter and dry to obtain a 2,4-D Na sustained-release agent (BIPIL-HC-2,4-D Na).

[0062] Prepare five sets of 9cm diameter culture dishes, add 10ml of test solution to each (a: deionized water, b: 100ppm 2,4-D Na solution, c: 0.02M NaCl solution, d: deionized water + BIPIL-HC-2,4-D Na, e: 0.02M NaCl solution + BIPIL-HC-2,4-D Na, the amount of 2,4-D Na in group b is the same as that in group d / e, and the amount of sustained-release agent carrier in group d and group e is the same), then put a layer of filter paper in the culture dish, and then put 10 rapeseed seeds on each filter paper. Grow in an incubator with a temperature of 26℃, a humidity of 85%, and a light intensity of 3000lx. The first three days are completely dark, and the next five days are alternating day and night (12 / 12). Measure the root length of rapeseed under different conditions, and compare the fresh weight and dry weight of the seeds.

[0063] like Figure 5 As shown, 0.02M NaCl solution has no side effects on rapeseed growth and can significantly promote the root and stem growth of rapeseed. In addition, BIPIL-HC has no obvious effect on rapeseed growth, indicating that BIPIL-HC has good biosafety and is suitable for use as a pesticide carrier. From the growth of rapeseed, after applying BIPIL-HC-2,4-DNa in 0.02M NaCl medium, the root length, fresh weight and dry weight of rapeseed were lower than those after the same dose and concentration of 2,4-D Na aqueous solution. These results show that BIPIL-HC-2,4-D Na has good herbicide activity and is affected by the ionic strength of the release medium.

Claims

1. Application of a bisimidazolyl polyionic liquid functionalized hydrothermal carbon in the preparation of a pesticide sustained-release agent, characterized in that: The preparation method of the bisimidazolyl polyionic liquid functionalized hydrothermal carbon comprises the following steps: (1) using a hydrothermal carbonization method to carbonize bamboo powder and a hydrochloric acid solution, adding an alkali solution to the reaction product, stirring, filtering and washing with water until the filtrate is neutral, thereby obtaining hydrothermal bamboo charcoal; Putting dichloromethane and 1-vinylimidazole into a reaction kettle for reaction, and obtaining the monomer N,N'-methylene-bis(1-(3-vinylimidazole)) chloride after the reaction is completed; (2) Take the above hydrothermal bamboo charcoal and N,N'-methylene-bis(1-(3-vinylimidazole)) chloride, add an initiator and a solvent, put them into a reactor and heat them for reaction to obtain the product bisimidazolyl polyionic liquid functionalized hydrothermal charcoal.

2. The use of the bisimidazolyl polyionic liquid functionalized hydrothermal carbon in the preparation of a pesticide sustained-release agent according to claim 1, characterized in that: The concentration of the bamboo powder in the hydrochloric acid solution in step (1) is 0.2-0.3 g / mL, and the concentration of the hydrochloric acid solution is 0.5-1.0 mol / L.

3. The use of the bisimidazolyl polyionic liquid functionalized hydrothermal carbon in the preparation of a pesticide sustained-release agent according to claim 1, characterized in that: The reaction temperature of the carbonization reaction in step (1) is 200-220° C., the carbonization time is 12-24 hours, and the alkali solution stirring time is 2-4 hours.

4. The use of the bisimidazolyl polyionic liquid functionalized hydrothermal carbon in the preparation of a pesticide sustained-release agent according to claim 1, characterized in that: The alkali solution in step (1) is a sodium hydroxide solution with a concentration of 0.2-0.25 mol / L.

5. The use of the bisimidazolyl polyionic liquid functionalized hydrothermal carbon in the preparation of a pesticide sustained-release agent according to claim 1, characterized in that: The molar ratio of dichloromethane to 1-vinylimidazole in step (1) is 1-3:2-4.

6. The use of the bisimidazolyl polyionic liquid functionalized hydrothermal carbon in the preparation of a pesticide sustained-release agent according to claim 1, characterized in that: In step (1), the reaction temperature of the reaction of dichloromethane and 1-vinylimidazole is 100-120° C., and the reaction time is 12-80 h.

7. The use of the bisimidazolyl polyionic liquid functionalized hydrothermal carbon in the preparation of a pesticide sustained-release agent according to claim 1, characterized in that: After the reaction in step (2) is completed, the mixture is first filtered and then washed with anhydrous ethyl acetate. The filter residue is dried to obtain the target compound.

8. The use of the bisimidazolyl polyionic liquid functionalized hydrothermal carbon in the preparation of a pesticide sustained-release agent according to claim 1, characterized in that: In step (2), the mass ratio of the hydrothermal charcoal, N,N'-methylene-bis(1-(3-vinylimidazole)) chloride and azobisisobutyronitrile is 10-12:15-25:1.4-2.

5.

9. The use of the bisimidazolyl polyionic liquid functionalized hydrothermal carbon in the preparation of a pesticide sustained-release agent according to claim 1, characterized in that: The solvent in step (2) is a mixed solvent of water and dimethyl sulfoxide, and the volume ratio of water to dimethyl sulfoxide is 1-2:1-2.

10. The use of the bisimidazolyl polyionic liquid functionalized hydrothermal carbon in the preparation of a pesticide sustained-release agent according to claim 1, characterized in that: The pesticide slow-release agent also includes Cl - The pesticide is 2,4-D sodium.

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