Nano-composite hydrogel biomimetic synergistic aid as well as preparation method and application thereof

Abstract

The invention discloses a nano-composite hydrogel biomimetic synergistic aid as well as a preparation method and application thereof, and relates to the technical field of agricultural preparation production. The nano composite hydrogel biomimetic synergistic aid comprises the following raw materials in percentage by mass: 1-3% of a polymeric monomer I, 1-3% of a polymeric monomer II, 0.01-0.05% of an initiator, 0.5-2% of a catalyst, 0.2-1% of amino-functionalized nano silicon dioxide and the balance of water. Wherein the polymeric monomer I is N-n-propylacrylamide and / or N, N-dimethylacrylamide; and the polymeric monomer II is one or more of N-(2-hydroxyethyl) acrylamide, N-(hydroxymethyl) acrylamide and N-[tris (hydroxymethyl) methyl] acrylamide. The nano-composite hydrogel biomimetic synergistic additive provided by the invention is prepared by a one-pot method, the process is simple, and the raw materials do not contain organic solvents. The prepared nano-composite hydrogel biomimetic synergistic additive belongs to biomimetic macromolecules, is stable in structure at high temperature and low temperature, and is insensitive to the change of temperature and pH value.

Description

Technical Field

[0001] The present invention relates to the technical field of agricultural formulation production, and particularly relates to a nano-composite hydrogel bio-mimetic synergistic adjuvant, a preparation method thereof and an application thereof. Background Art

[0002] Hydrogel is a kind of polymer material with a three-dimensional network structure using water as the dispersion medium. Due to its special cross-linked structure, it has the advantages of adjustable properties and morphology, good biocompatibility, strong viscosity, easy degradation, strong mechanical properties and large specific surface area. Hydrogels have currently been applied in the fields of drug release, medical beauty, contact lenses and sensors. The core structure of the hydrogel is the internal three-dimensional space network, and the structure transformation of the polymerization network is realized by changing the polymer type, adjusting the cross-linking density and the polymer concentration. Common monomers used to prepare hydrogels include biopolymers, nanoparticles, small molecules and metal / ligand units.

[0003] Nano-silica materials have been widely concerned due to their porous structure, stable framework structure, amorphous framework composition with a certain wall thickness and easy doping, large specific surface area, and modifiable inner surface. The nano-silica material itself does not have activity, but due to the presence of a lot of silanol groups on the inner surface of its pores, it can be alkylated modified to bind some functional groups to the inner surface, and a large number of organic groups (such as mercapto, amino, phenyl and vinyl groups, etc.) are embedded into the nano-silica material, making it have a high loading capacity for different drugs and having broad prospects in the application of carrier materials.

[0004] Nano-composite hydrogel is a polymer-based nano-composite material, which is a nano-composite material prepared by dispersing nanoparticles as rigid fillers in a polymer matrix. The polymer-based nano-composite material not only has the advantages of the toughness, flexibility and strength of the polymer, but also has the characteristics of the magnetism, conductivity, heat resistance and rigidity of the nano-filler. In actual production, the nano-silica material acts as a physical cross-linking agent in the hydrogel, and is mainly added to the hydrogel network structure by a one-step polymerization method after direct blending. However, there is only a weak interaction between the nano-filler of this nano-composite hydrogel and the hydrogel matrix, and the nanoparticles are prone to agglomeration, resulting in the non-uniformity of the nano-filler polymer network, and further affecting the performance of the nanoparticles in the hydrogel matrix. Eventually, the thermodynamic state of the whole system is unstable, prone to stratification and precipitation, and the product function is lost.

[0005] The nano-composite hydrogel required in agricultural production needs to meet the following conditions before it can be used: 1. The nano-composite hydrogel must be a fluid that can flow before use, because semi-solid or solid nano-composite hydrogels cannot be diluted with water for use; 2. The viscosity of the nano-composite hydrogel needs to be less than 500 mPa·s, because too high viscosity will affect the pourability of the product and is not convenient for use; 3. After the nano-composite hydrogel is diluted with water, it can form a semi-solid hydrogel film on the surface of the plant after spraying, drip irrigation or fertigation, or form a slow-release layer after combining with the soil, then it has the function of slow-releasing pesticides and fertilizers and has practical application significance; 4. After the nano-composite hydrogel is diluted with water according to the mass ratio of 1:(100 - 2000), it still has the ability to form a hydrogel film or a slow-release layer with stable structure and slow-release effect.

[0006] Therefore, it is necessary to optimize the nanoparticles and manufacturing process as a whole to create a nano-composite hydrogel product suitable for agricultural use. Summary of the Invention

[0007] The present invention provides a nano-composite hydrogel biomimetic synergistic adjuvant, its preparation method and application. By selecting amino-functionalized silica to act as a physical cross-linking agent in the hydrogel, the agglomeration problem caused by hydrogen bonds between the silanol groups on the surface of nano-silica and water molecules is solved. At the same time, the nano-composite hydrogel provided by the present invention is a fluid before use, and its viscosity is between 100 - 200 mPa·s, which is easy to pour and mix evenly with water. And after the nano-composite hydrogel is diluted with water according to the mass ratio of 1:(100 - 2000), it can form a hydrogel film on the surface of the plant or form a slow-release layer after combining with the soil, better assisting the active ingredients in pesticides and fertilizers to enter the animals and plants efficiently and quickly to exert their efficacy; it is safe for users and friendly to the environment, and has broad market prospects. Specifically, it is realized through the following technologies.

[0008] A nano-composite hydrogel biomimetic synergistic adjuvant, the raw materials of which include, by mass percentage: 1 - 3% of polymerization monomer one, 1 - 3% of polymerization monomer two, 0.01 - 0.05% of initiator, 0.5 - 2% of catalyst, 0.2 - 1% of amino-functionalized nano-silica, and the rest is water;

[0009] Optionally, the polymerization monomer one is N-n-propylacrylamide and / or N,N-dimethylacrylamide.

[0010] Optionally, the polymerization monomer two is one or more of N-(2-hydroxyethyl)acrylamide, N-(hydroxymethyl)acrylamide, N-[tris(hydroxymethyl)methyl]acrylamide.

[0011] Specifically, the polymerization monomer one is N,N-dimethylacrylamide.

[0012] Specifically, the polymerization monomer II is N-(2-hydroxyethyl) acrylamide.

[0013] For the nano-composite hydrogel bio-mimicking synergistic adjuvant prepared by the present invention, when the terminal groups contain a suitable proportion of hydroxyl groups, the polymer after polymerization can swell in water and be suspended in water. When all the terminal groups are hydroxyl groups, the synthesized product is prone to form transparent flocculent precipitates, affecting the use of the product. Therefore, by introducing hydrophobic alkyl groups into the terminal groups and adjusting the proportion of hydroxyl groups in the terminal groups, the polymer can be kept stable in water. Based on the above principle, the present invention only needs to select one or more monomers from the polymerization monomer I and the polymerization monomer II respectively, and carry out a polymerization reaction according to the weight percentages of the polymerization monomer I and the polymerization monomer II given by the present invention (1-3% and 1-3%), so as to ensure that the proportion of alkyl groups and hydroxyl groups in the terminal groups of the polymer after polymerization is within a suitable proportion range, and further prepare a stable nano-composite hydrogel bio-mimicking synergistic adjuvant.

[0014] Further, its raw materials by mass percentage include: 2% of polymerization monomer I, 2% of polymerization monomer II, 0.03% of initiator, 1.5% of catalyst, 0.6% of amino-functionalized nano-silica, and the balance is water.

[0015] When preparing the nano-composite hydrogel bio-mimicking synergistic adjuvant in this patent, in order to cause the polymerization reaction of the polymerization monomer I and the polymerization monomer II, it is only necessary to maintain a certain concentration of free radicals in the reaction system. Therefore, the initiator can be selected from any compound commonly used in the art and capable of achieving the above purpose. These initiators can be mixed in any proportion and will not affect the occurrence of the reaction and the reaction effect. Similarly, the catalyst can also be one or several catalysts commonly used in the art and mixed in any proportion.

[0016] Further, the initiator is one or more of ammonium persulfate, potassium persulfate, sodium persulfate, and 2,2'-azobis(2-methylpropionamidine) dihydrochloride.

[0017] Furthermore, the initiator can be ammonium persulfate, potassium persulfate, sodium persulfate or 2,2'-azobis(2-methylpropionamidine) dihydrochloride.

[0018] Furthermore, the initiator can be ammonium persulfate, potassium persulfate, sodium persulfate and 2,2'-azobis(2-methylpropionamidine) dihydrochloride, and the mass ratio is (1-4):(2-3):(2-3):(1-4).

[0019] Further, the catalyst is one or more of N,N,N,N-tetramethylethylenediamine, ethylenediamine, sodium sulfite, and sodium thiosulfate.

[0020] Furthermore, the catalyst can be N,N,N,N-tetramethylethylenediamine, ethylenediamine, sodium sulfite or sodium thiosulfate.

[0021] Furthermore, the catalyst can be N,N,N,N-tetramethylethylenediamine, ethylenediamine, sodium sulfite and sodium thiosulfate, and the mass ratio is (1-4):(2-3):(2-3):(1-4).

[0022] The amino-functionalized nano-silica used in the preparation of the above nano-composite hydrogel bio-mimetic synergistic adjuvant of the present invention generally has a particle size between 20-300 nm.

[0023] The present invention also provides a preparation method of the above nano-composite hydrogel bio-mimetic synergistic adjuvant, including the following steps:

[0024] Under an inert gas protection environment at 40-50 °C and 0.11-0.13 MPa (such as a reaction kettle filled with argon, nitrogen, etc.), add polymerization monomer one and polymerization monomer two while stirring in water to obtain a clear system;

[0025] Add an initiator and a catalyst to the clear system until completely dissolved and stir at 70-80 °C for reaction;

[0026] After the reaction is completed, cool down to 35-40 °C, add amino-functionalized nano-silica, stir and disperse, stand still, and make up the water to a predetermined amount to obtain the finished product of the nano-composite hydrogel bio-mimetic synergistic adjuvant.

[0027] The present invention also provides the application of the above nano-composite hydrogel bio-mimetic synergistic adjuvant, which is used as a formulation adjuvant or tank mix adjuvant for pesticides or fertilizers.

[0028] Further, when used as a formulation adjuvant for pesticides or fertilizers, add the nano-composite hydrogel bio-mimetic synergistic adjuvant during the production stage of pesticides or fertilizers.

[0029] Further, when used as a tank mix adjuvant for pesticides or fertilizers, add the nano-composite hydrogel bio-mimetic synergistic adjuvant when using pesticides or fertilizers on-site.

[0030] Furthermore, the method of adding the nano-composite hydrogel bio-mimetic synergistic adjuvant when using pesticides or fertilizers on-site is: mix the nano-composite hydrogel bio-mimetic synergistic adjuvant and water in a mass ratio of 1:(100-2000) evenly, then add pesticides or fertilizers, and mix evenly again before application.

[0031] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0032] 1. The nano - composite hydrogel bionic synergistic adjuvant prepared by the present invention belongs to bionic macromolecules, which are structurally stable at high and low temperatures, insensitive to changes in temperature and pH value, ensuring its usability under different weather conditions. Meanwhile, it can be mixed with different pesticides and fertilizers.

[0033] 2. When the nano - composite hydrogel bionic synergistic adjuvant of the present invention is used together with pesticides and fertilizers, the amino - functionalized nano - silica can not only adsorb pesticide and fertilizer molecules, but also, through the synergistic effect with raw materials such as polymers, form a semi - solid hydrogel film on the plant surface after dilution for spraying, drip irrigation or flushing, or form a slow - release layer after combining with the soil, improving the adsorption of pesticides and / or fertilizers on the plant surface and the slow - release in the soil, being resistant to rain erosion, increasing the utilization rate of pesticides and fertilizers, and significantly enhancing the efficacy of pesticides and / or fertilizers.

[0034] 3. The preparation method of the nano - composite hydrogel bionic synergistic adjuvant provided by the present invention is prepared by the one - pot method, and the preparation process is simple; all raw materials do not contain organic solvents, eliminating environmental pollution caused by organic solvents and being safe for production personnel and users. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 and 2 are respectively the transmission electron micrograph and scanning electron micrograph of the nano - composite hydrogel bionic synergistic adjuvant prepared in Example 1.

[0036] Figure 3 is the leaf adsorption diagram of the nano - composite hydrogel bionic synergistic adjuvant prepared in Examples 1 - 20. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0037] The technical solutions of the present invention will be described clearly and completely below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of them. All other embodiments obtained by those of ordinary skill in the art without creative efforts based on the embodiments of the present invention belong to the scope of protection of the present invention.

[0038] In some embodiments of the present invention, for the nano - composite hydrogel bionic synergistic adjuvant prepared, the raw materials are in mass percentages as follows: monomer 1 1 - 3wt%, monomer 2 1 - 3wt%, initiator 0.01 - 0.05wt%, catalyst 0.5 - 2wt%, amino - functionalized nano - silica 0.2 - 1wt%, and the balance is water.

[0039] Optionally, monomer 1 is N - n - propylacrylamide and / or N,N - dimethylacrylamide.

[0040] Optionally, the polymerization monomer II is one or more of N-(2-hydroxyethyl)acrylamide, N-(hydroxymethyl)acrylamide, and N-[tris(hydroxymethyl)methyl]acrylamide.

[0041] In each specific embodiment of the present invention for preparing the nano-composite hydrogel bio-mimetic synergistic adjuvant, in order to ensure the normal progress of the polymerization reaction of the polymerization monomer I and the polymerization monomer II, a certain concentration of free radicals needs to be maintained in the reaction system. Based on this, the initiator can be selected from any compound commonly used in the art and capable of achieving the above purpose. These initiators can be mixed in any proportion without affecting the occurrence of the reaction and the reaction effect. Similarly, the catalyst can also be one or several catalysts commonly used in the art and mixed in any proportion.

[0042] In some specific embodiments, the initiator is one or more of ammonium persulfate, potassium persulfate, sodium persulfate, and 2,2'-azobis(2-methylpropylimid) dihydrochloride.

[0043] Optionally, the initiator can be ammonium persulfate, potassium persulfate, sodium persulfate, or 2,2'-azobis(2-methylpropylimid) dihydrochloride.

[0044] Optionally, the initiator can be ammonium persulfate, potassium persulfate, sodium persulfate, and 2,2'-azobis(2-methylpropylimid) dihydrochloride, and the mass ratio is (1-4):(2-3):(2-3):(1-4).

[0045] In some specific embodiments, the catalyst is one or more of N,N,N,N-tetramethylethylenediamine, ethylenediamine, sodium sulfite, and sodium thiosulfate.

[0046] Optionally, the catalyst can be N,N,N,N-tetramethylethylenediamine, ethylenediamine, sodium sulfite, or sodium thiosulfate.

[0047] Optionally, the catalyst can be N,N,N,N-tetramethylethylenediamine, ethylenediamine, sodium sulfite, and sodium thiosulfate, and the mass ratio is (1-4):(2-3):(2-3):(1-4).

[0048] The method for preparing the nano-composite hydrogel bio-mimetic synergistic adjuvant in each specific embodiment of the present invention is as follows:

[0049] Under an inert gas protection environment at 40-50°C and 0.11-0.13 MPa (such as a reaction kettle filled with argon, nitrogen, etc.), while stirring in water, add the polymerization monomer I and the polymerization monomer II to obtain a clear system;

[0050] Add the initiator and the catalyst to the clear system until completely dissolved, and stir and react at 70-80°C;

[0051] After the reaction is completed, the temperature is lowered to 35-40° C., amino-functionalized nano-silicon dioxide is added, stirred and dispersed, and allowed to stand to obtain a finished product of a nano-composite hydrogel biomimetic synergistic additive.

[0052] In the specific embodiments provided by the present invention, all reagents are commercially available unless otherwise specified. Specifically, amino-functionalized nano-silica was purchased from Sigma-Aldrich; N-[tris(hydroxymethyl)methyl]acrylamide was purchased from MacLean; and other reagents were purchased from Aladdin.

[0053] Example 1

[0054] The nanocomposite hydrogel biomimetic synergistic aid provided in this embodiment is prepared by the following preparation method.

[0055] (1) Weigh 2 g of polymerizable monomer (N,N-dimethylacrylamide, CAS No.: 2680-03-7), 2 g of polymerizable monomer (N-(2-hydroxyethyl)acrylamide, CAS No.: 7646-67-5), 0.03 g of initiator (ammonium persulfate), 1.5 g of catalyst (N,N,N,N-tetramethylethylenediamine), and 0.6 g of amino-functionalized nano-silica, and set aside.

[0056] (2) Add water to the reactor (to fully dissolve / disperse the raw materials such as polymer monomer 1, polymer monomer 2, initiator, catalyst, amino-functionalized nano-silica, etc., the mass of which is generally 15 times the total weight of polymer monomer 1 and polymer monomer 2), heat to 40-50°C, add polymer monomer 1 and polymer monomer 2 while stirring, and at the same time, introduce pure N 2 , adjust the exhaust valve to maintain a slight positive pressure in the reactor between 0.11-0.13MPa until the solution in the reactor becomes clear;

[0057] (3) Add the initiator solution and the catalyst solution to the reactor, rapidly raise the temperature to 75°C ± 5°C, stir for 1 hour, then rapidly cool down the temperature in the reactor to 35-40°C, add the amino-functionalized nano-silica under stirring, continue stirring and dispersing for 10 minutes, and let stand for 24 hours to obtain a nanocomposite hydrogel biomimetic synergistic agent.

[0058] Embodiment 2-10

[0059] The nanocomposite hydrogel biomimetic synergistic aids provided in Examples 2-10 are prepared by using a preparation method substantially the same as that of Example 1, with the differences shown in Table 1 below.

[0060] Table 1

[0061] Examples 11 - 15

[0062] The nano - composite hydrogel biomimetic synergistic adjuvant provided in Examples 11 - 15 is prepared by using substantially the same raw materials and preparation methods as in Example 1, with the difference being the type and dosage of the initiator. Specifically, it is shown in Table 2 below.

[0063] Table 2

[0064] Examples 16 - 20

[0065] The nano - composite hydrogel biomimetic synergistic adjuvant provided in Examples 16 - 20 is prepared by using substantially the same raw materials and preparation methods as in Example 1, with the difference being the type and dosage of the accelerator. Specifically, it is shown in Table 3 below.

[0066] Table 3

[0067] Comparative Example 1

[0068] The nano - composite hydrogel biomimetic synergistic adjuvant provided in this comparative example is prepared by using substantially the same raw materials and preparation methods as in Example 1, with the difference being that this comparative example selects commercially available conventional nano - silica to replace the amino - functionalized nano - silica.

[0069] Comparative Example 2

[0070] The nano - composite hydrogel biomimetic synergistic adjuvant provided in this comparative example is prepared by using substantially the same raw materials and preparation methods as in Example 1. The difference is that the ends of the polymer monomers added in this comparative example are all hydrophilic hydroxyl groups, that is, instead of using Monomer 1 in Example 1, all Monomer 2 is used. Specifically, 2 g of N - (hydroxymethyl) acrylamide and 2 g of N - [tris (hydroxymethyl) methyl] acrylamide are selected as Monomer 2.

[0071] Comparative Example 3

[0072] The nano - composite hydrogel biomimetic synergistic adjuvant provided in this comparative example is prepared by using substantially the same raw materials and preparation methods as in Example 1. The difference is that the ends of the polymer monomers added in this comparative example are all hydrophobic alkyl groups, that is, instead of using Monomer 2 in Example 1, all Monomer 1 is used. Specifically, 2 g of N - n - propyl acrylamide and 2 g of N,N - dimethyl acrylamide are selected as Monomer 1.

[0073] Test Example 1: Morphology Detection of the Nano - composite Hydrogel Biomimetic Synergistic Adjuvant of Example 1

[0074] The nano-composite hydrogel bio-mimicking synergistic adjuvant prepared in Example 1 was dropped onto a copper grid of a transmission electron microscope, and 1 drop of 1% phosphotungstic acid was added. After drying at room temperature, it was detected.

[0075] The results of the transmission electron microscope are as Figure 1 shown. The amino-functionalized silica particles contained in the prepared nano-composite hydrogel bio-mimicking synergistic adjuvant have uniform particle sizes, about 20 - 50 nm, regular particle shapes, obvious morphologies, and are surrounded by a network of hydrogels.

[0076] The nano-composite hydrogel bio-mimicking synergistic adjuvant prepared in Example 1 was diluted to an appropriate concentration, then dropped on a silicon wafer and dried, and was sputter-coated with gold before observation.

[0077] The results of the scanning electron microscope are as Figure 2 shown. The amino-functionalized silica particles contained in the prepared nano-composite hydrogel bio-mimicking synergistic adjuvant have uniform particle sizes, about 20 - 50 nm, regular particle shapes, and obvious morphologies.

[0078] Test Example 2: Determination of the stability of the nano-composite hydrogel bio-mimicking synergistic adjuvant

[0079] The nano-composite hydrogel bio-mimicking synergistic adjuvants prepared in Examples 1 - 20 and the nano-composite hydrogel bio-mimicking synergistic adjuvants prepared in Comparative Examples 1 - 3 were respectively tested for room temperature stability (25 °C, 90 d), high temperature stability (54 °C, 14 d), low temperature stability (4 °C, 14 d), and pH stability. For pH stability, the nano-composite hydrogel bio-mimicking synergistic adjuvant was mixed with HCl solution (pH value = 3) or NaOH solution (pH value = 9) at a weight ratio of 1:100, and observed after standing at 25 °C for 4 h. The results are shown in Table 4 below.

[0080] Table 4 Test results of the stability of the nano-composite hydrogel bio-mimicking synergistic adjuvant

[0081]

[0082] The test results in Table 4 above show that the nano-composite hydrogel bio-mimicking synergistic adjuvants prepared in Examples 1 - 20 are stable under room temperature, high temperature, low temperature, acidic (pH value = 3) and alkaline (pH value = 9) conditions, indicating that they can be mixed with most pesticides and / or fertilizers.

[0083] In Comparative Example 1, since it is unmodified ordinary nano-silica, the aggregation problem caused by hydrogen bonds between a large number of silanol groups on its surface and water molecules forms a white sand-like precipitate.

[0084] In Comparative Example 2, the two polymerization monomers have strong hydrophilicity, and the hydrogen bond network formed between the chain polymers is too strong, so the prepared nano-composite hydrogel bio-mimicking synergistic adjuvant has a transparent flocculent precipitate.

[0085] The two polymerization monomers of Comparative Example 3 have strong hydrophobicity, and the chain polymers are likely to aggregate due to hydrophobic forces. Therefore, the prepared nano-composite hydrogel bio-mimetic synergistic adjuvant is phase-separated from water, forming a large amount of white colloidal insoluble matter.

[0086] Test Example 3: Viscosity measurement of nano-composite hydrogel bio-mimetic synergistic adjuvant

[0087] The nano-composite hydrogel bio-mimetic synergistic adjuvants prepared in Examples 1-20 were subjected to viscosity measurement. 10-20 mL was taken for viscosity measurement, the measurement temperature was 20 °C, the measurement time was 3 min, and the machine model was LVDV-2T (Shanghai Fangrui Instrument Co., Ltd.). The results are shown in Table 5.

[0088] Table 5 Viscosity measurement results of nano-composite hydrogel bio-mimetic synergistic adjuvant

[0089]

[0090] The results in Table 5 show that the viscosities of the nano-composite hydrogel bio-mimetic synergistic adjuvants prepared in Examples 1-20 are between 160 and 180, indicating that different formulations and ratios have no obvious effect on the product; the viscosities are similar and are all less than 500 mPa·s, which is easy to pour and mix uniformly with water, facilitating use.

[0091] Test Example 4: Leaf adsorption test of nano-composite hydrogel bio-mimetic synergistic adjuvant

[0092] The nano-composite hydrogel bio-mimetic synergistic adjuvants prepared in Examples 1-20 were subjected to leaf adsorption test measurement. A 500 mL, 0.1% (W / W) aqueous solution of nano-composite hydrogel bio-mimetic synergistic adjuvant was prepared, and the clear water without synergist was used as the blank control. The leaves of Epipremnum aureum were immersed in the solution for 1 second, and then the leaves were placed on a black cloth for photographing. The water stain situation on the leaves was observed, and the leaf adsorption ability of the nano-composite hydrogel bio-mimetic synergistic adjuvant was evaluated by visual inspection.

[0093] The results are as Figure 3 shown. The nano-composite hydrogel bio-mimetic synergistic adjuvants prepared in Examples 1-20 all have good adhesion effects, can form a hydrogel film, and different formulations and ratios have no obvious effect on the product.

[0094] Test Example 5: Soil adsorption test of nano-composite hydrogel bio-mimetic synergistic adjuvant

[0095] The nano-composite hydrogel bio-mimicking synergistic adjuvant prepared in Examples 1-20 was subjected to a soil adsorption test. A dehydrated soil plug was treated with 40 mL of a 1% (W / W) aqueous solution of the nano-composite hydrogel bio-mimicking synergistic adjuvant. First, the weight of the soil plug was weighed, and then it was placed in an incubator with a temperature control of 25 °C. At regular intervals, the weight of the soil plug was weighed to determine the remaining moisture in the soil plug. During the 5-day test period, the average evaporation rate was calculated to evaluate the moisture slow-release effect of the slow-release layer formed by the nano-composite hydrogel bio-mimicking synergistic adjuvant and the soil. The test results are shown in Table 6.

[0096] Table 6 Soil Adsorption and Slow-Release Test Results of Nano-Composite Hydrogel Bio-Mimicking Synergistic Adjuvant

[0097]

[0098] The results in Table 6 above show that the 1% aqueous solution of the nano-composite hydrogel bio-mimicking synergistic adjuvant prepared in Examples 1-20 can form a slow-release layer with the soil, reducing the evaporation rate of moisture in the soil. The average evaporation amount is 0.73 - 0.75% / h, significantly lower than the blank control of 1.58% / h. There is no obvious difference among the products with different formulations and ratios, and the average evaporation amounts are not very different.

[0099] Test Example 6: Field Efficacy Test of Nano-Composite Hydrogel Bio-Mimicking Synergistic Adjuvant

[0100] To verify the role of the nano-composite hydrogel bio-mimicking synergistic adjuvant prepared in Examples 1-20 of the present invention in pesticide synergistic enhancement, a commercial formulation of 40% bensulfuron-methyl · pretilachlor dispersible oil suspension was used as the test pesticide, and the nano-composite hydrogel bio-mimicking synergistic adjuvant prepared in Examples 1-20 of the present invention was used as the test adjuvant to carry out a field efficacy evaluation test on the pre-emergence soil sealing of direct-seeded rice fields by the nano-composite hydrogel bio-mimicking synergistic adjuvant synergistically with 40% bensulfuron-methyl · pretilachlor dispersible oil suspension. The test design is as follows:

[0101] The test was a plot test, with each plot test area of 30 m 2 , and each treatment had 4 replicates. Ridges were made between plots to ensure no water mixing between plots, and a 0.5 m protection row was set. The dosage per mu was 200 mL, and 30 L of water was added for manual spraying treatment; in addition, the nano-composite hydrogel bio-mimicking synergistic adjuvant prepared in Example 1 was used for unmanned aerial vehicle (UAV) spraying treatment. There was no plot set, the test area was 2 mu, the dosage per mu was 200 mL, and 2 L of water was added for UAV spraying treatment. The protection row between the large area treated by UAV and other treatments was increased to 20 m to reduce the impact of agent drift on the test results. The treatment with clear water was used as the blank control group.

[0102] The control effects were investigated 14 days and 21 days after pesticide application. The investigation methods and result analysis are as follows:

[0103] For each treatment of manual spraying, five points were selected, and one sampling was carried out at each point. Each sample was for the number of weed plants in 1 m 2 For the treatment of UAV aerial spraying, four points were randomly selected, and five-point sampling was carried out at each point. Each sample was for the number of weed plants in 1 m 2 The number of weed plants. The formula for the control effect (%) is (the number of plants in the blank control group - the number of plants in the treatment group) / the number of plants in the blank control group * 100. And the statistical software was used to conduct a completely randomized single-factor statistical analysis on the plant control effect of each treatment. Different lowercase letters in the table indicate significant differences at the 5% level, and the synergistic ratio of the plant control effect of each treatment was calculated. The formula is: Synergistic ratio of control effect = [(control effect of the group with nano-composite hydrogel biomimetic synergistic adjuvant - control effect of the group without nano-composite hydrogel biomimetic synergistic adjuvant) / control effect of the group without nano-composite hydrogel biomimetic synergistic adjuvant] × 100%. The results are shown in Table 5 below.

[0104] Table 7 Field synergistic effect of nano-composite hydrogel biomimetic synergistic adjuvant

[0105] The results in Table 7 show that the nano-composite hydrogel biomimetic synergistic adjuvant prepared in Examples 1-20 of the present invention has a significant synergistic effect in synergistically controlling with the commercial preparation 40% bensulfuron-methyl · pretilachlor dispersible oil suspension. The field control effect at 14 days increased from 73.77% to over 93%, and the synergistic ratio was 27%. The field control effect at 21 days increased from 61.14% to over 85%, and the synergistic ratio was 40%. There was no significant difference in the field control effect between Treatment 21 (prepared in Example 1 (aerial spraying)) and Treatment 1 (prepared in Example 1 (manual spraying)), and both were significantly higher than the field control effect of Treatment 22 (without adjuvant), indicating that the nano-composite hydrogel biomimetic synergistic adjuvant still has a significant synergistic effect when using UAV for aerial spraying treatment.

[0106] The above specific embodiments have described the implementation of the present invention in detail. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the claims and technical concept of the present invention, various simple modifications and changes can be made to the technical solutions of the present invention, and these simple variations all belong to the protection scope of the present invention.

Claims

1. A nanocomposite hydrogel biomimetic synergistic aid, characterized in that: The raw materials include, by mass percentage: 1-3% of polymerized monomer 1, 1-3% of polymerized monomer 2, 0.01-0.05% of initiator, 0.5-2% of catalyst, 0.2-1% of amino-functionalized nano-silicon dioxide, and the rest is water; The first polymerizable monomer is N-n-propyl acrylamide and / or N,N-dimethyl acrylamide; the second polymerizable monomer is one or more of N-(2-hydroxyethyl) acrylamide, N-(hydroxymethyl) acrylamide, and N-[tris(hydroxymethyl)methyl] acrylamide.

2. The nanocomposite hydrogel biomimetic synergistic aid according to claim 1, characterized in that: The raw materials include, by mass percentage, 2% of polymerization monomer, 2% of polymerization monomer, 0.03% of initiator, 1.5% of catalyst, 0.6% of amino-functionalized nano-silicon dioxide, and the rest is water.

3. The nanocomposite hydrogel biomimetic synergistic aid according to claim 1, characterized in that: The initiator is one or more of ammonium persulfate, potassium persulfate, sodium persulfate, and 2,2-azobis(2-methylpropylimidamide) dihydrochloride.

4. The nanocomposite hydrogel biomimetic synergistic aid according to claim 1, characterized in that: The catalyst is one or more of N,N,N,N-tetramethylethylenediamine, ethylenediamine, sodium sulfite, and sodium thiosulfate.

5. The method for preparing the nanocomposite hydrogel biomimetic synergistic aid according to any one of claims 1 to 4, characterized in that: The following steps are involved: Under an inert gas protection environment of 40-50° C. and 0.11-0.13 MPa, polymerizing monomer 1 and polymerizing monomer 2 are added into water while stirring to obtain a clarifying system; Add initiator and catalyst to the clarified system until they are completely dissolved, and stir to react at 70-80° C.; After the reaction is completed, the temperature is lowered to 35-40° C., amino-functionalized nano-silicon dioxide is added, stirred and dispersed, allowed to stand, and water is added to a predetermined amount to obtain a finished product of a nano-composite hydrogel biomimetic synergistic aid.

6. The use of the nanocomposite hydrogel biomimetic synergistic aid according to any one of claims 1 to 4, characterized in that: Used as a formulation adjuvant or tank mix adjuvant for pesticides or fertilizers.

7. The use of the nanocomposite hydrogel biomimetic synergistic aid according to claim 6, characterized in that: When used as a formulation adjuvant for pesticides or fertilizers, the nanocomposite hydrogel biomimetic synergistic adjuvant is added during the production stage of the pesticides or fertilizers.

8. The use of the nanocomposite hydrogel biomimetic synergistic aid according to claim 6, characterized in that: When used as a tank-mix adjuvant for pesticides or fertilizers, the nanocomposite hydrogel biomimetic synergistic adjuvant is added when the pesticides or fertilizers are used on site.

9. The use of the nanocomposite hydrogel biomimetic synergistic aid according to claim 8, characterized in that: The method of adding the nanocomposite hydrogel biomimetic synergist when using pesticides or fertilizers on site is: mixing the nanocomposite hydrogel biomimetic synergist and water in a mass ratio of 1:(100-2000), then adding the pesticide or fertilizer, mixing again and then applying.

Images