A super-wetting spreading material and its preparation method and application

Abstract

The present invention discloses a superwetting spreading material and a preparation method and application thereof, belonging to the field of superwetting materials. The structural formula of the superwetting spreading material provided by the present invention is shown in formula (I): #imgabs0# In the formula (I), m is 1 to 10; n1 and n2 are independently selected from 4 to 20. The superwetting spreading material provided by the present invention is constructed by electrostatic interaction between organic acids with different hydrophobic chain lengths and fatty diamines, has low surface tension, can be quickly spread and wetted on the surface of a hydrophobic substrate, has a stable molecular structure and is not easily hydrolyzed, and the source of the raw materials for preparation is green and renewable, has no phytotoxic effect on crops, and has little impact on human health and the ecological environment, and has a wide range of applications in the fields of pesticides, coatings, adhesives, inks or daily chemicals.

Description

Technical Field

[0001] The invention belongs to the field of superwetting materials, and in particular relates to a superwetting spreading material and a preparation method and application thereof. Background Art

[0002] Whether high-speed pesticide droplets can efficiently wet and spread on the hydrophobic leaf surface directly affects the control effect of pesticides on pests and diseases. Especially during the spraying process of pesticide drones, the bouncing, splashing, drifting and sliding of pesticide droplets on the leaf surface lead to about 60% of pesticide loss, and less than 0.1% of the pesticide is effectively used by the target organisms, which brings serious agricultural non-point source pollution, ecological environment damage and excessive pesticide residues in crops. The bouncing and splashing of droplets on plant leaves are mainly due to the poor hydrophobicity and droplet adhesion of the leaf surface. The three major food crops in my country, rice, wheat and corn, as well as common weeds, have almost super-hydrophobic properties on their leaf surfaces due to the presence of waxy hydrophobic layers and micro-nano structures on their surfaces. The efficient deposition of pesticide droplets on these leaf surfaces becomes more difficult, which will further affect the prevention and control of pests and diseases by the active ingredients of pesticides.

[0003] In recent years, a large number of scientific research teams have devoted themselves to the study of the wetting and spreading of high-speed droplets on super-hydrophobic plant surfaces. In particular, polyether-modified silicone materials have been widely used in pesticide adjuvants due to their low surface tension and excellent wetting and spreading properties. For example, Chinese invention patent CN104971662A discloses a trisiloxane double-headed Gemini superwetter, which has a surface tension of less than 25mN / m and can spread rapidly on solid surfaces such as plant leaves, metal materials, plastics, glass, and wood, with a final contact angle close to zero. It can be used in the fields of pesticides, coatings, adhesives, inks, and daily chemicals. Although polyether-modified silicone surfactants are a typical superwetting and spreading agent material and have been widely used in practical applications, pesticide droplets containing silicone surfactants are very likely to splash when they hit the leaf surface at high speed, the deposition efficiency of pesticides on the leaf surface is low, and some molecular structures are more easily decomposed after encountering water, which has a certain phytotoxic effect on crops. Therefore, it is currently urgent to develop a green, environmentally friendly, and efficiently deposited non-silicone superwetting spreading material. Summary of the invention

[0004] In order to overcome the problems existing in the above-mentioned prior art, one of the objects of the present invention is to provide a superwetting spreading material, which is constructed by electrostatic interaction between organic acids with different hydrophobic chain lengths and fatty diamines, has a low surface tension, and can be quickly spread and wetted on the surface of a hydrophobic substrate.

[0005] The second object of the present invention is to provide a method for preparing the superwetting spreading material, which is simple and the raw materials are green and environmentally friendly.

[0006] The third object of the present invention is to provide an application of the above-mentioned super-wetting spreading material in the fields of pesticides, coatings, adhesives, inks or daily chemicals.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is:

[0008] The first aspect of the present invention provides a superwetting spreading material, the structural formula of the superwetting spreading material is shown in formula (I):

[0009]

[0010] In the formula (I), m is 1 to 10; n1 and n2 are independently selected from 4 to 20.

[0011] Preferably, m, n1, and n2 are positive integers.

[0012] Preferably, in the formula (I), m is 2 to 9; further preferably, in the formula (I), m is 2 to 8; further preferably, in the formula (I), m is 2, 4, 6 or 8.

[0013] Preferably, in the formula (I), n1 and n2 are independently selected from 6 to 19; further preferably, in the formula (I), n1 and n2 are independently selected from 8 to 18; further preferably, in the formula (I), n1 and n2 are independently selected from 8, 10, 12, 14, 16 or 18.

[0014] Preferably, the superwetting spreading material comprises the following preparation raw materials: fatty diamine and fatty acid.

[0015] Preferably, in the raw materials for preparing the superwetting spreading material, the fatty diamine includes at least one of methylenediamine, ethylenediamine, propylenediamine, butylenediamine, pentylenediamine, hexylenediamine, heptylenediamine, octylenediamine, nonanediamine or decanediamine; further preferably, in the raw materials for preparing the superwetting spreading material, the fatty diamine includes at least one of ethylenediamine, propylenediamine, butylenediamine, pentylenediamine, hexylenediamine, heptylenediamine or octylenediamine; further preferably, in the raw materials for preparing the superwetting spreading material, the fatty diamine includes at least one of ethylenediamine, butylenediamine, hexylenediamine or octylenediamine.

[0016] Preferably, in the raw materials for preparing the super-wet spreading material, the fatty acid includes at least one of butyric acid, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, lauric acid, tridecanoic acid, myristic acid, pentadecanoic acid, hexadecanoic acid, pearl fatty acid, stearic acid, nonadecanoic acid or arachidic acid; further preferably, in the raw materials for preparing the super-wet spreading material, the fatty acid includes at least one of octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, lauric acid, tridecanoic acid, myristic acid, pentadecanoic acid, hexadecanoic acid, pearl fatty acid or stearic acid; further preferably, in the raw materials for preparing the super-wet spreading material, the fatty acid includes at least one of octanoic acid, decanoic acid, lauric acid, tridecanoic acid, myristic acid, pentadecanoic acid, hexadecanoic acid, pearl fatty acid or stearic acid.

[0017] Preferably, in the raw materials for preparing the superwetting spreading material, the molar ratio of fatty diamine to fatty acid is 1:(0.1-5); further preferably, in the raw materials for preparing the superwetting spreading material, the molar ratio of fatty diamine to fatty acid is 1:(0.3-3); further preferably, in the raw materials for preparing the superwetting spreading material, the molar ratio of fatty diamine to fatty acid is 1:(0.5-2).

[0018] The second aspect of the present invention provides a method for preparing the super-wetting spreading material described in the first aspect of the present invention, comprising the following steps: mixing a fatty diamine, a fatty acid and a first solvent for reaction, removing the first solvent, adding a second solvent for recrystallization, and obtaining the super-wetting spreading material.

[0019] Preferably, in the raw materials for preparing the super-wetting spreading material, the first solvent includes at least one of acetone, ethanol, methanol, acetonitrile or ethyl acetate; further preferably, in the raw materials for preparing the super-wetting spreading material, the first solvent includes at least one of acetone, ethanol, methanol or acetonitrile; even further preferably, in the raw materials for preparing the super-wetting spreading material, the first solvent includes at least one of acetone, ethanol or methanol.

[0020] Preferably, in the raw materials for preparing the super-wetting spreading material, the second solvent includes at least one of ethyl acetate, acetone, ethanol, methanol, petroleum ether, n-hexane or tetrahydrofuran; further preferably, in the raw materials for preparing the super-wetting spreading material, the second solvent includes at least one of ethyl acetate, acetone, ethanol, petroleum ether, n-hexane or tetrahydrofuran; even further preferably, in the raw materials for preparing the super-wetting spreading material, the second solvent includes at least one of ethyl acetate, acetone, petroleum ether, n-hexane or tetrahydrofuran.

[0021] Preferably, in the preparation method, the mixed reaction temperature is 40-100°C; further preferably, in the preparation method, the mixed reaction temperature is 45-90°C; further preferably, in the preparation method, the mixed reaction temperature is 50-80°C.

[0022] Preferably, in the preparation method, the mixing reaction time is 1 to 12 hours; further preferably, in the preparation method, the mixing reaction time is 2 to 11 hours; further preferably, in the preparation method, the mixing reaction time is 3 to 10 hours.

[0023] The third aspect of the present invention provides an application of the superwetting spreading material described in the first aspect of the present invention or the superwetting spreading material prepared by the preparation method described in the second aspect of the present invention in the fields of pesticides, coatings, adhesives, inks or daily chemicals.

[0024] Preferably, the superwetting spreading material is added to the pesticide at a concentration of 0.01 to 1 wt %; further preferably, the superwetting spreading material is added to the pesticide at a concentration of 0.05 to 0.5 wt %; further preferably, the superwetting spreading material is added to the pesticide at a concentration of 0.08 to 0.2 wt %.

[0025] Preferably, the pesticide comprises glyphosate.

[0026] The beneficial effects of the present invention are:

[0027] The invention provides a superwetting spreading material, which is constructed by electrostatic interaction between organic acids with different hydrophobic chain lengths and fatty diamines, has low surface tension, and can quickly spread and wet on the surface of a hydrophobic substrate.

[0028] Specifically, compared with the prior art, the present invention has the following advantages:

[0029] (1) The superwetting spreading material of the present invention has excellent static / dynamic surface tension, with a static surface tension as low as 22 mN / m. When the pesticide droplets contact the hydrophobic leaf surface, the material molecules can quickly migrate and adsorb on the newly formed solid-liquid surface, which can quickly promote the wetting and spreading of the pesticide droplets on the surface. In addition, the material self-assembles in an aqueous solution to form spherical micelles that can aggregate into a network structure. Once the droplets collide with the hydrophobic surface, the spherical micelles in the network structure can be quickly adsorbed on the micro-nano structure of the hydrophobic surface, thereby effectively inhibiting the bouncing and splashing of the pesticide droplets, improving the bioavailability of the pesticide, and reducing the pollution of the ecological environment caused by the application of excessive pesticides.

[0030] (2) The superwetting spreading material of the present invention does not require complicated synthesis steps and can be obtained through simple electrostatic interaction between fatty diamines and fatty acids. The raw material source is green and renewable, the molecular structure is stable and not easily hydrolyzed, it has no phytotoxic effect on crops, and has little impact on human health and the ecological environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is the infrared spectrum of the superwetting spreading material synthesized in Example 3.

[0032] Figure 2 This is the H-NMR spectrum of the superwetting spreading material synthesized in Example 3.

[0033] Figure 3 The static / dynamic surface tension diagrams and data of the superwetting spreading materials of Examples 1 to 6.

[0034] Figure 4 Schematic diagram of the change of pesticide droplets of superwetting spreading materials on the barnyard grass leaf surface over time in Application Examples 1 to 6.

[0035] Figure 5 The graph shows the change of contact angle of pesticide droplets of superwetting spreading material on barnyard grass leaf surface over time in Application Examples 1 to 6.

[0036] Figure 6 The graph shows the change of the spreading area of ​​the pesticide droplets of the super-wetting spreading material on the barnyard grass leaf surface over time in Application Examples 1 to 6.

[0037] Figure 7 This is a diagram of the wetting states of the pesticide droplets and water of the superwetting spreading material on the leaf surfaces of different plants in Application Example 3.

[0038] Figure 8 The graph shows the high-speed impact and deposition behavior of pesticide droplets of the superwetting spreading material of Application Examples 1 to 6 and Comparative Example 1 on the leaf surface of barnyard grass.

[0039] Fig. 9 This is a diagram showing the wetting, spreading, high-speed impact and deposition behavior of pesticide droplets using the super-wetting spreading material of Comparative Example 2 on the leaf surface of barnyard grass. DETAILED DESCRIPTION

[0040] The content of the present invention is further described in detail below through specific examples. It should also be understood that the following examples are only used to further illustrate the present invention and cannot be construed as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the principles set forth in the present invention all belong to the scope of protection of the present invention. The specific process parameters and the like in the following examples are also only examples within a suitable range, that is, those skilled in the art can make a selection within a suitable range through the description herein, and are not limited to the specific data exemplified below. The raw materials, reagents or devices used in the following examples and comparative examples, unless otherwise specified, can all be obtained from conventional commercial sources, or can be obtained by existing known methods.

[0041] Example 1

[0042] Dissolve 1 mol of hexamethylenediamine and 2 mol of octanoic acid in solvent acetone, heat and stir at 50°C for 3 hours, use a rotary evaporator to remove the solvent to obtain a crude superwetting spreading material, then recrystallize using ethyl acetate and acetone, and dry in a vacuum drying oven to obtain a pure superwetting spreading material OAO.

[0043] Example 2

[0044] Dissolve 1 mol of hexamethylenediamine and 2 mol of decanoic acid in solvent acetone, heat and stir at 60°C for 5 hours, use a rotary evaporator to remove the solvent to obtain a crude superwetting spreading material, then recrystallize using ethyl acetate and acetone, and dry in a vacuum drying oven to obtain a pure superwetting spreading material CAC.

[0045] Example 3

[0046] Dissolve 1 mol of hexamethylenediamine and 2 mol of lauric acid in solvent acetone, heat and stir at 80°C for 6 hours, use a rotary evaporator to remove the solvent to obtain a crude superwetting spreading material, then use petroleum ether and acetone to recrystallize, and dry in a vacuum drying oven to obtain a pure superwetting spreading material LAL.

[0047] Example 4

[0048] Dissolve 1 mol of hexamethylenediamine and 2 mol of myristic acid in solvent acetone, heat and stir at 80°C for 8 hours, use a rotary evaporator to remove the solvent to obtain a crude superwetting spreading material, then use n-hexane and tetrahydrofuran for recrystallization, and dry in a vacuum drying oven to obtain a pure superwetting spreading material MAM.

[0049] Example 5

[0050] Dissolve 1 mol of hexamethylenediamine and 2 mol of hexadecanoic acid in solvent acetone, heat and stir at 80°C for 10 hours, use a rotary evaporator to remove the solvent to obtain a crude superwetting spreading material, then use n-hexane and acetone for recrystallization, and dry in a vacuum drying oven to obtain a pure superwetting spreading material PAP.

[0051] Example 6

[0052] Dissolve 1 mol of hexamethylenediamine and 2 mol of stearic acid in solvent acetone, heat and stir at 80°C for 10 hours, use a rotary evaporator to remove the solvent to obtain a crude super-wetting spreading material, then recrystallize using ethyl acetate and acetone, and dry in a vacuum drying oven to obtain a pure super-wetting spreading material SAS.

[0053] Comparative Example 1

[0054] Purchase commercially available silicone wetting and spreading material Silwet-L77.

[0055] Comparative Example 2

[0056] Dissolve 1 mol of diethylenetriamine and 2 mol of lauric acid in solvent acetone, heat and stir at 80°C for 6 hours, use a rotary evaporator to remove the solvent to obtain a crude superwetting spreading material, then recrystallize using petroleum ether and ethyl acetate, and dry in a vacuum drying oven to obtain a pure superwetting spreading material DETAL3.

[0057] Application Examples 1 to 6

[0058] The materials obtained in Examples 1 to 6 were respectively configured into 0.1wt% OAO solution, CAC solution, LAL solution, MAM solution, PAP solution and SAS solution, and the original pesticide glyphosate was added to obtain 0.2wt% glyphosate aqueous solution, respectively obtaining Application Examples 1 to 6, and further measuring the wettability, spreadability and deposition behavior of the above pesticide aqueous solutions on plant leaves.

[0059] Application Comparative Examples 1 to 2

[0060] The materials obtained in Comparative Examples 1 to 2 were respectively configured into 0.1wt% Silwet-L77 solution and DETAL3 solution, and then the original pesticide glyphosate was added to obtain 0.2wt% glyphosate aqueous solution, respectively obtaining Application Comparative Examples 1 to 2, and the wettability, spreadability and deposition behavior of the above pesticide aqueous solutions on plant leaves were further measured.

[0061] Product effect testing

[0062] Figure 1 This is the infrared spectrum of the superwetting spreading material obtained in Example 3. Figure 1 Medium, 2794.8cm -1 Belongs to the CH3 stretching vibration absorption peak; 2721.5cm -1 Belongs to the CH2 stretching vibration absorption peak; 1512.6cm -1 and 1408.1cm -1 The absorption peaks at 1700 cm-1 are respectively attributed to the antisymmetric stretching vibration absorption peak and the symmetric stretching vibration absorption peak of C=O in fatty carboxylate. -1 There is no carbonyl absorption peak in the amide bond, indicating that the fatty acid in this material appears in the form of fatty carboxylate rather than forming an amide covalent bond with fatty diamine.

[0063] Figure 2 This is the H NMR spectrum of the superwetting spreading material obtained in Example 3. The chemical shifts of H in the material are: 0.8 (-CH3), 1.2 (-CH2-CH2- in fatty acids), 1.4 (-CH2-CH2- in fatty amines), 1.5 (-CH2-CH2-COO - ), 1.6(NH2 + -CH2-CH2), 2.1(-CH2-COO - ), 2.8(-CH2-NH2 + ).

[0064] The static / dynamic surface tension results of the superwetting spreading materials of Examples 1 to 6 are as follows: Figure 3 shown. Figure 3 a is a graph showing the static surface tension of different superwetting spreading materials as their concentrations change. Figure 3 b is the static surface tension diagram of different superwetting spreading materials. Figure 3 Figure c is a graph showing the dynamic surface tension of different superwetting spreading materials. Figure 3 Figure d is a graph showing the dynamic surface tension of water and LAL materials of different concentrations. Figure 3 From Figures 3a and 3b, it can be seen that as the length of the hydrophobic chain of the material molecules increases, the surface tension first decreases and then increases. When the raw material is lauric acid, the surface tension of the formed material LAL reaches the lowest (22mN / m). Figure 3 From Figure 3c and Figure 3d, we can see that the dynamic surface tension of the material changes in accordance with the static surface tension, and the dynamic surface tension of LAL is optimal, indicating that LAL molecules can migrate and adsorb rapidly at the solid-liquid interface, which is conducive to the rapid spreading and wetting of the molecule on the hydrophobic surface.

[0065] The contact angles of the pesticide droplets of the superwetting spreading materials of Application Examples 1 to 6 on the leaf surface of barnyard grass are as follows: Figure 4 and Figure 5As shown. The contact angle of pure water droplets on the barnyard grass leaf surface is 145.7°, which hardly changes with time, indicating that pure water droplets are difficult to spread and wet on the barnyard grass leaf surface, and can easily roll off the leaf surface. However, the wetting and diffusion behavior of the superwetting spreading material pesticide droplets of application examples 1 to 6 are enhanced. When the carbon chain increases and the material is LAL, the LAL droplets exhibit rapid diffusion behavior. Complete spreading and wetting are achieved at the moment the droplet contacts the surface (about 1s), and the corresponding equilibrium contact angle value is 0°. Further increasing the carbon chain length will weaken the diffusion ability (such as MAM), but complete diffusion can still be achieved after 180 seconds. However, when the number of carbon atoms in the hydrophobic chain is greater than 14 (PAP and SAS), the droplets cannot achieve complete diffusion and wetting on the leaf surface, and the contact angle of the droplets gradually increases. LAL droplets not only diffuse the fastest, but also have the largest final droplet diffusion area (such as Figure 6 The rapid diffusion behavior of LAL droplets is attributed to its low dynamic surface tension. The rapid diffusion and dense adsorption of LAL molecules on the newly formed solid-liquid interface promote the rapid spreading of droplets.

[0066] Figure 7 The wetting and spreading properties of the LAL pesticide droplets prepared in Application Example 3 on cabbage, Bauhinia leaves, barnyard grass and calla lily leaves. When pure water droplets are dropped on these leaf surfaces, most of them appear as spherical droplets, indicating that these leaf surfaces have a certain degree of hydrophobicity. When LAL is added to the droplets, it is found that the LAL droplets have excellent wetting and spreading properties on different leaf surfaces, especially when the leaf surface is Bauhinia leaves, LAL can also promote the penetration of the droplets into the leaf surface, which can further improve the utilization rate of pesticides on such leaf surfaces.

[0067] Figure 8 The deposition behavior of pure water, superwetting spreading material pesticide droplets of application examples 1 to 6 and application comparative example 1 on the leaf surface of barnyard grass is shown. When the pure water droplets hit the leaf surface, they splash completely, and finally no water droplets remain on the leaf surface, indicating that it is difficult for pure water to deposit on the leaf surface that is almost superhydrophobic. However, the addition of superwetting spreading material will enhance the inhibition of droplet splashing. For OAO, CAC and SAS droplets, the droplets partially rebound and splash, and finally some spherical or hemispherical droplets are left on the leaf surface. LAL, MAM and PAP droplets not only show complete inhibition of splashing and remain on the leaf, but also continue to spread on the surface, resulting in a larger wetting area. The droplets of the organosilicon wetting spreading material of application comparative example 1 show obvious splashing during the collision process, indicating that the organosilicon wetting spreading material cannot be used alone as a pesticide adjuvant, and other wetting spreading materials are needed for auxiliary use.

[0068] Fig. 9 A and Fig. 9In the figure b, respectively, the wetting and spreading properties of the pesticide droplets on the leaf surface of barnyard grass constructed by using polyamine (diethylenetriamine) and lauric acid in comparative example 2 and the high-speed impact and deposition behavior of the droplets. Fig. 9 In figure a, it can be seen that when the amine used is a polyamine (more than two amino groups), its droplet has poor wetting and spreading properties on barnyard grass, and the contact angle is about 85°. The contact angle does not change significantly with time. Fig. 9 In b, it can be seen that the droplets of the material will splash when they hit the barnyard grass leaf surface at high speed, and fewer droplets will eventually deposit on the leaf surface, indicating that the polyamine material cannot help the droplets to deposit efficiently on the leaf surface. The above results show that the material formed by the polyamine is not suitable for use as a pesticide adjuvant.

[0069] The present invention prepares a super-wetting spreading material through electrostatic interaction between organic acids with different hydrophobic chain lengths and fatty diamines. The super-wetting spreading material has a low surface tension as low as 22 mN / m, can quickly spread and wet on the surface of a hydrophobic substrate, has a stable molecular structure and is not easily hydrolyzed, and the raw materials for preparation are green and renewable, have no phytotoxic effect on crops, and have little impact on human health and the ecological environment. The super-wetting spreading material has a wide range of applications in the fields of pesticides, coatings, adhesives, inks or daily chemicals.

Claims

1. Use of a compound of formula (I) as a superwetting spreading material, characterized in that: The compound of formula (I) is: The compound of formula (I) is prepared from the following raw materials: fatty diamine, fatty acid; The fatty diamine is at least one of propylene diamine, butane diamine, pentane diamine, hexane diamine, heptane diamine, octanediamine, nonane diamine or decanediamine; The fatty acid is at least one of butyric acid, valeric acid, caproic acid, heptanoic acid, caprylic acid, nonanoic acid, capric acid, undecanoic acid, lauric acid, tridecanoic acid, myristic acid, pentadecanoic acid, hexadecanoic acid, pearly acid, stearic acid, nonadecanoic acid or arachidic acid; The molar ratio of the fatty diamine to the fatty acid is 1:(0.1-5); The compound of formula (I) is prepared by a method comprising the following steps: mixing a fatty diamine, a fatty acid and a first solvent for reaction, removing the first solvent, adding a second solvent for recrystallization, and obtaining the compound of formula (I); the first solvent is at least one of acetone, ethanol, methanol, acetonitrile and ethyl acetate; The super-wetting spreading material is applied in the field of pesticides.

2. The use according to claim 1, characterized in that: The second solvent is at least one of ethyl acetate, acetone, ethanol, methanol, petroleum ether, n-hexane or tetrahydrofuran.

3. The application according to claim 1, characterized in that: The mixed reaction temperature is 40-100°C; And / or, the mixing reaction time is 1 to 12 hours.

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