阅读说明：本技术 聚醚基农药助剂及其制备方法与应用 (Polyether-based pesticide adjuvant and preparation method and application thereof ) 是由 陈兴江 李长权 董均方 刘兴江 刘声国 汪汉成 陆宁 贾蒙骜 罗杰 刘国权 蔡翼 于 2020-08-19 设计创作，主要内容包括：本发明公开了一种聚醚基农药助剂及其制备方法与应用,属于农药助剂技术领域。本发明将1-十二烷胺和1,12-十二烷二元胺借助其氨基接枝于甘油丙氧基三缩水甘油基醚的环氧基团上形成单体,并用1-甲基咪唑催化甘油丙氧基三缩水甘油基醚上游离环氧基团间聚合生成聚酯主链,即得聚醚基农药助剂。本发明能够显著提升药液的叶片表面附着量和附着牢固度,经检测,将本发明聚醚基农药助剂按质量比1:500-1:4000添加到农药水溶液中,农药微滴在烟草叶片上的接触角介于0°-50°之间；干燥后浸水12h,农药存留量达到50％-87％。(The invention discloses a polyether-based pesticide adjuvant and a preparation method and application thereof, belonging to the technical field of pesticide adjuvants. According to the invention, 1-dodecylamine and 1, 12-dodecanediamine are grafted on an epoxy group of glycerol propoxy triglycidyl ether by virtue of amino groups of the dodecylamine and the 1-methylimidazole is used for catalyzing the polymerization between the upstream epoxy groups of the glycerol propoxy triglycidyl ether to generate a polyester main chain, so that the polyether-based pesticide auxiliary agent is obtained. The polyether-based pesticide auxiliary agent can remarkably improve the blade surface adhesion amount and the adhesion firmness of liquid medicine, and is detected to be added into a pesticide aqueous solution according to the mass ratio of 1:500-1:4000, wherein the contact angle of pesticide droplets on tobacco blades is between 0 and 50 degrees; after drying, soaking for 12h, and the pesticide retention amount reaches 50-87%.)

1. The polyether-based pesticide adjuvant is characterized in that the molecular structural formula of the polyether-based pesticide adjuvant is as follows:

wherein n is 2-200, and further O, OH, NH₂Respectively represent an oxygen atom, a hydroxyl group, a secondary amino group and a boa group.

2. The polyether-based pesticidal adjuvant of claim 1, wherein the polyether-based pesticidal adjuvant has a viscosity average molecular weight of 2.0kDa to 200 kDa.

3. The polyether-based pesticidal adjuvant according to claim 1, wherein the polyether-based pesticidal adjuvant has a hydrophilic-lipophilic balance coefficient HLB of 3.0 to 16.0.

4. A method for preparing the polyether-based pesticide adjuvant according to any one of claims 1 to 3, characterized in that 1-dodecylamine and 1, 12-dodecanediamine are grafted onto the epoxy groups of the glycerol propoxide triglycidyl ether via the amino groups thereof to form monomers, and 1-methylimidazole is used to catalyze the polymerization between the free epoxy groups on the glycerol propoxide triglycidyl ether to form the polyester backbone, so as to obtain the polyether-based pesticide adjuvant.

5. The method according to claim 4, characterized in that it comprises the following steps:

firstly, dissolving glycerol propoxyl triglycidyl ether, 1-dodecylamine, 1, 12-dodecanediamine and 1-methylimidazole in ethanol to obtain a reaction solution;

secondly, stirring the reaction solution obtained in the first step at room temperature;

thirdly, heating the reaction solution obtained in the second step to 40-80 ℃, and continuously stirring and preserving heat to ensure that substances in the reaction solution fully react to obtain a reaction product;

and fourthly, heating and distilling the reaction product, and distilling off ethanol to obtain the polyether-based pesticide auxiliary agent.

6. The method according to claim 5, wherein in the reaction solution prepared in the first step, the ratio of ethanol: glycerol propoxyttriglycidyl ether: 1-dodecylamine: the mass ratio of 1, 12-dodecanediamine to 1-methylimidazole is 100 g: 10-50 g: 1-50 g: 1-50 g: 10-100 mg.

7. The method as claimed in claim 5, wherein the second-step stirring time is 8-24h, and the stirring rotation speed is 500-1500 r/min.

8. The use of the polyether-based pesticidal adjuvant of any one of claims 1 to 3, characterized in that the polyether-based pesticidal adjuvant is added to an aqueous pesticide solution.

9. The use according to claim 8, characterized in that the mass ratio of the polyether-based pesticide adjuvant to the aqueous pesticide solution is 1:500 to 1: 4000.

Technical Field

The invention relates to a polyether-based pesticide adjuvant and a preparation method and application thereof, belonging to the technical field of pesticide adjuvants.

Background

Pesticide adjuvant innovation is always a core part in pesticide formulation research, and is vital to improving the application effect of spray type pesticides. At present, the dosage of various auxiliary agents is about 2-3 ten thousand tons every year in China, and the two main types of nonionic emulsifiers and sulfonic acid dispersing and wetting agents are mainly concentrated. The organosilicon auxiliary agent with good application effect can reduce the application amount by 1/3-1/2 compared with the conventional method, but even if the utilization rate of the powder pesticide is about 10 percent, the utilization rate of the liquid pesticide is about 20 percent, the rest 40-60 percent of the liquid pesticide falls to the ground, and 20-40 percent of the pesticide floats in the air. The pesticide in the air can return to the land through the precipitation and is spread along with the precipitation and irrigation or seeps along with the water to pollute the underground water. Published data in 2006 in the united states indicate that 90% of agricultural watersheds detect pesticides, 50% of water wells and 33% of ground water likewise detect pesticides. Pesticide pollution poses great harm to biodiversity, and 32% of organisms on the earth are destroyed in 25 years from 1970 to 1995 according to the report published by world wildlife foundation 1998, and pesticide pollution is one of the main causes of biodestruction. In order to improve the utilization rate of pesticides and reduce environmental pollution, a great deal of research work is carried out aiming at the analysis of the reasons of low utilization rate of pesticides and the development of efficient pesticide preparations.

The current research results at home and abroad show that: the presence of a hydrophobic/superhydrophobic waxy layer on the plant surface is a major cause of low adhesion. In the process of collision between the liquid medicine and the leaf surface, the liquid drops expand on the leaf surface due to inertia and then retract due to surface tension, and the retracted liquid medicine drops are easy to bounce off the leaf surface, so that the liquid medicine loss is caused. The rebound proportion and the strength of the pesticide liquid droplets on the leaf surfaces are weakened, and the pesticide utilization rate is favorably improved. For the purpose of this research, the current mainstream method is to change the fluid properties of the liquid medicine by means of the application of the surfactant and the spreading agent, so that the rebound of the liquid medicine on the leaf surface is reduced and the accumulation of the liquid medicine is improved. The more intensive research shows that the effectiveness of the surfactant is related to the speed of the surfactant migrating to the surface of the liquid drop in the liquid drop forming process, whether the surfactant can rapidly migrate to a contact interface at the moment of the collision of the liquid drop and the leaf surface and the outward turning of a hydrophobic group is completed on the contact interface determines the accumulation efficiency of the liquid medicine on the leaf surface. However, the application of surfactants is not as satisfactory as overdue because the collision time is as short as a few milliseconds and the hydrophobic chain inversion rapidly breaks through the barrier of the surface tension of the aqueous phase. There have also been some studies to change the rheological properties of the drug solution into non-newtonian fluids by introducing polymer derivative developing agents. When the liquid medicine droplets collide with the leaf surface, the deformation of the liquid medicine droplets after collision reduces the retraction delay and the retraction delay, and finally the accumulation rate of the liquid medicine droplets on the leaf surface is improved. Common spreading agents such as sodium alginate, gelatin, starch, silicone polymers, and polymeric carboxylic acids. Maher et al, 8.2016, reported a new method for the attachment of a high-efficiency drug drop to a leaf surface, which is established by means of an in-situ precipitation reaction of anions and cations, and which is implemented by a two-phase spraying method, and is self-claimed to improve the attachment rate of an aqueous solution by more than 10 times, and the method does not describe the attachment firmness. According to the test of the applicant, the literature report method does not help to improve the fastness of the liquid medicine.

Disclosure of Invention

Based on the polyether-based pesticide auxiliary agent, the preparation method and the application thereof, provided by the invention, the attachment amount and the attachment firmness of pesticide droplets on the surface of a plant can be effectively improved.

The technical scheme of the invention is as follows:

in a first aspect, the present invention provides a polyether-based pesticide adjuvant, which has a molecular structural formula:

wherein n is 2-200, and further O, OH, NH₂Respectively represent an oxygen atom, a hydroxyl group, a secondary amino group and a boa group.

Preferably, the viscosity average molecular weight of the polyether-based pesticide adjuvant is 2kDa to 200 kDa.

Preferably, the hydrophilic-lipophilic balance coefficient HLB of the polyether-based pesticide adjuvant is 3.0-16.0.

In a second aspect, the invention further provides a method for preparing the polyether-based pesticide adjuvant, 1-dodecylamine and 1, 12-dodecanediamine are grafted on an epoxy group of glycerol propoxide triglycidyl ether by virtue of amino groups of the 1-dodecylamine and the 1, 12-dodecylamine to form a monomer, and 1-methylimidazole is used for catalyzing polymerization between free epoxy groups on the glycerol propoxide triglycidyl ether to generate a polyester main chain, so that the polyether-based pesticide adjuvant is obtained.

Specifically, the method for preparing the polyether-based pesticide adjuvant comprises the following steps:

firstly, dissolving glycerol propoxyl triglycidyl ether, 1-dodecylamine, 1, 12-dodecanediamine and 1-methylimidazole in ethanol to obtain a reaction solution;

secondly, stirring the reaction solution obtained in the first step at room temperature;

thirdly, heating the reaction solution obtained in the second step to 40-80 ℃, and continuously stirring and preserving heat to ensure that substances in the reaction solution fully react to obtain a reaction product;

and fourthly, heating and distilling the reaction product, and distilling off ethanol to obtain the polyether-based pesticide auxiliary agent.

Preferably, in the reaction solution prepared in the first step, the ratio of ethanol: glycerol propoxyttriglycidyl ether: 1-dodecylamine: the mass ratio of 1, 12-dodecanediamine to 1-methylimidazole is 100 g: 10-50 g: 1-50 g: 1-50 g: 10-100 mg.

Preferably, the stirring time of the second step is 8-24h, and the stirring speed is 500-1500 r/min.

In a third aspect, the invention further provides an application of the polyether-based pesticide auxiliary agent, and specifically the polyether-based pesticide auxiliary agent is added into a pesticide aqueous solution.

Preferably, the mass ratio of the polyether-based pesticide auxiliary agent to the pesticide aqueous solution is 1:500-1: 4000.

The technical principle of the invention is as follows: because the leaf surface of terrestrial plants (particularly human cultivation crops, fruits, vegetables and the like) has a hydrophobic wax layer, the attachment property and the attachment firmness of hydrophobic drug drops are higher theoretically, but drug liquid droplets with strong hydrophobicity cannot be stably and uniformly dispersed in a water phase. Either the delicate balance between hydrophilic and hydrophobic properties of the drug solution droplet is selected to be controlled, or the transition from the hydrophilic phase to the hydrophobic phase is initiated when the drug solution droplet contacts the surface of the plant. The polyether-based pesticide auxiliary agent has the function of electrostatically inducing hydrophilic-hydrophobic phase transformation, and can help pesticide droplets to keep good hydrophilic-hydrophobic water balance and uniformly and stably disperse in water; when the liquid medicine microdroplets contact with the surface of the plant, the hydrophilic phase is converted into the hydrophobic phase, and the liquid medicine microdroplets converted into the hydrophobic phase are firmly attached to the surface of the plant. Therefore, high adhesion is realized by single-phase spray electrostatic adsorption, firm adhesion is realized by hydrophobic phase transition, and the purposes of improving the utilization rate of pesticides and reducing pesticide loss are achieved.

The invention has the beneficial effects that: according to the invention, 1-dodecylamine and 1, 12-dodecanediamine firstly react with epoxy groups on glycerol propoxy triglycidyl ether to form graft, and then the crosslinking among the residual epoxy groups is completed under the catalysis of 1-methylimidazole, so that the main functional groups of the prepared product comprise: positively charged amino groups with high attachment function, a firmly attached polyether backbone and firmly attached alkane side chains. In addition, the obtained product is clear and transparent, has excellent fluidity, can be mixed with water in any ratio, is a clear water solution, can obviously reduce the contact angle of the water solution on the surface of the tobacco leaf under the dilution of 500-4000 times, and has the effect of promoting the attachment and extension of pesticide droplets on the surface of the tobacco leaf.

When the polyether-based pesticide auxiliary agent is prepared, the ratio of 1-dodecylamine to 1, 12-dodecanediamine and the ratio of alkylamine to glycerol propoxy triglycidyl ether can be adjusted to adjust the product, namely the lipophilic and hydrophilic balance coefficient of the polyether-based pesticide auxiliary agent. Meanwhile, the molecular weight of the polyether-based pesticide adjuvant is regulated and controlled through monomer concentration regulation, reaction temperature regulation, reaction time regulation and the like. And the high-efficiency pesticide auxiliary agent is obtained, the blade surface adhesion amount and the adhesion firmness of the pesticide liquid can be remarkably improved, and the application prospect in the field of pesticide reduction and use is wide.

Through detection, the polyether-based pesticide auxiliary agent is added into a pesticide aqueous solution according to the mass ratio of 1:500-1:4000, and the contact angle of pesticide droplets on tobacco leaves is between 0 and 50 degrees; after drying, soaking for 12h, and the pesticide retention amount reaches 50-87%.

Drawings

FIG. 1 is a diagram of polyether-based pesticide adjuvant drug-loaded particles;

fig. 2 is a dynamic change diagram of polyether-based pesticide adjuvant drug-loaded particles on the surface of plant leaves.

Detailed Description

The present invention will be described in detail with reference to the following embodiments in order to make the aforementioned objects, features and advantages of the invention more comprehensible. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein, but rather should be construed as broadly as the present invention is capable of modification in various respects, all without departing from the spirit and scope of the present invention.

First, the detection method according to the embodiment of the present invention is explained as follows:

(1) the method for measuring the viscosity average molecular weight comprises the following steps: the viscosity measurement is carried out by adopting a Ubbelohde viscometer, and the specific measurement method is carried out by referring to the national standard GB T10247-2008 of the viscosity measurement method.

(2) The hydrophilic-lipophilic balance coefficient is measured by an emulsification method;

mixing sorbitan trioleate (HLB is 1.8) and potassium oleate (HLB is 20) in proportion, and respectively preparing oil phase standard liquids with HLB values of 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0, 11.0, 12.0, 13.0, 14.0, 15.0, 16.0, 17.0, 18.0 and 19.0. Mixing the oil phase standard solution, the emulsifier to be tested and water in a ratio of 15:5:80, and stirring for 10min at 1500rpm on a magnetic stirrer. Taking 50mL of the solution in a test tube with a plug and a scale, standing at room temperature, recording and standing for 10min, and separating out the volume of a water layer. And taking the corresponding value of the standard oil with the optimal stability as the oil-water balance coefficient, namely the HLB value, of the emulsifier to be detected.

(3) The contact angle was measured using a contact angle measuring instrument, and the contact surface was a tobacco surface. 5 mu L of surfactant aqueous solution to be measured diluted by 1000 times is dripped on a tobacco opium in a contact angle measuring instrument, and the contact angle is measured by photographing and observing.

(4) The amount of pesticide remaining was measured by HPLC. The detection method of different pesticides is different, and azoxystrobin is taken as an example for introduction. The chromatographic column adopts a C18 column, and the mobile phase is acetonitrile: the flow rate of water is 1mL/min, the column temperature is 35 ℃, the detection is carried out by adopting an ultraviolet absorption method, and the detection wavelength is 305 nm.