Thickening synergist suitable for glyphosate compound aqueous solution and preparation method thereof

Abstract

The invention belongs to the technical field of pesticides, and particularly relates to a thickening synergist suitable for a glyphosate compound aqueous solution and a preparation method of the thickening synergist. The preparation method comprises the following steps: polymerizing an unsaturated polyamine monomer, double-bond modified fumed silica and methacryloyloxyethyl trimethyl ammonium chloride to obtain a white carbon black loaded cationic polyamine polymer, namely the thickening synergist. According to the preparation method, double-bond white carbon black and a hydrophilic monomer are polymerized and grafted on a molecular chain through a chemical bond to obtain the thickening synergist, so that the solubility of the thickening synergist in water is greatly improved, glyphosate and a compound aqueous solution thereof can still have relatively high viscosity after being diluted with water, and the pesticide effect is remarkably improved.

Description

Technical Field

[0001] The invention belongs to the technical field of pesticides, and particularly relates to a thickening and synergist suitable for a glyphosate compound water agent and a preparation method thereof. Background Art

[0002] At present, the thickening aids used in glyphosate compound water are generally achieved by simple compounding of conventional adjuvants. For example, the Chinese invention patent with application number 201810323942.1 uses lauramide propyl amine oxide, lauroyl sarcosine triethanolamine, lauramide propyl betaine and sodium fatty acid methyl ester sulfonate to compound the thickening aid; the Chinese invention patent with application number 20221170893.X discloses thickening aids including sodium fatty alcohol ether sulfate, alkyl glucosides, cocoamidopropyl betaine, ethanol, sodium dioctyl sulfosuccinate and silicone; the Chinese invention patent with application number 20201 The Chinese invention patent No. 1609718.2 discloses a thickening aid obtained by compounding propylene glycol stearate, sorbitan triisostearate, dodecyl dimethyl betaine, lauryl amide propyl amine oxide and water; the Chinese invention patent with application number 201810279857.X compounded a thickening aid by using erucic acid PKO, cocamidopropyl betaine, tallow amine polyoxyethylene ether, potassium indole butyrate, dodecyl glucoside, polyhexamethylene guanidine, polyethylene glycol and deionized water.

[0003] Pesticide formulations need to be diluted 100 to 1000 times during use. The thickening additive obtained by compounding has a small molecular weight, and the thickening effect after dilution is minimal, making it difficult to increase the adhesion of the agent on the plant surface. Small molecule additives have poor resistance to rain erosion. After the application of the pesticide, the efficacy will decrease significantly or even become ineffective after being washed away by rain, and the pesticide needs to be sprayed again. Summary of the invention

[0004] The technical problem to be solved by the present invention is: the present invention provides a dilution-resistant thickening and enhancing agent suitable for glyphosate compound water agent and a preparation method thereof.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is: A method for preparing a thickening and synergist suitable for glyphosate compound water-based agent, comprising the following steps: polymerizing an unsaturated polyamine monomer, double-bond modified fumed silica and an unsaturated cationic monomer to obtain a silica-loaded cationic polyamine polymer, which is a thickening and synergist.

[0006] Another technical solution adopted by the present invention is: the thickening synergist is prepared by the preparation method of the thickening synergist suitable for the glyphosate compound water agent.

[0007] The beneficial effects of the present invention are as follows: the preparation method of the present invention polymerizes double-bond white carbon black and hydrophilic monomers, and obtains a thickening and synergistic agent by chemical bond grafting on the molecular chain, which greatly increases its solubility in water and can be used in glyphosate and its composite aqueous solution that require high transparency. It can make glyphosate and its composite aqueous solution still have a high viscosity after being diluted with water, increase the adhesion of the liquid medicine on the plant surface, and at the same time, the polyamine group and the cationic group can also provide good wetting and synergistic effects, significantly improving the efficacy. DETAILED DESCRIPTION

[0008] In order to explain the technical content, achieved objectives and effects of the present invention in detail, the following is an explanation in conjunction with the implementation modes.

[0009] A method for preparing a thickening synergist suitable for a glyphosate compound water agent comprises the following steps: polymerizing an unsaturated polyamine monomer, double-bond modified fumed silica and an unsaturated cationic monomer to obtain a silica-loaded cationic polyamine polymer, namely the thickening synergist.

[0010] From the above description, it can be seen that the beneficial effects of the present invention are: white carbon black, especially fumed white carbon black, is a thickener with excellent performance due to its small particle size and large specific surface area, and is used in many fields. However, white carbon black is not suitable as a thickener for pesticide aqueous solution, in which the preparation is required to be completely transparent. Although white carbon black has a certain hydrophilicity due to the presence of surface hydroxyl groups, it cannot be completely dissolved in water.

[0011] The present invention polymerizes double bond white carbon black with a hydrophilic monomer and grafts it onto a molecular chain through chemical bonds, which greatly increases its solubility in water and can be used in glyphosate and its composite aqueous solution that require high transparency. It can make glyphosate and its composite aqueous solution still have a high viscosity after being diluted with water, increase the adhesion of the liquid medicine on the plant surface, and at the same time, the polyamine group and the cationic group can also provide better wetting and synergistic effects, significantly improving the efficacy of the medicine.

[0012] The present invention obtains a grafted cationic white carbon loaded polymer thickening synergist through polymerization reaction. The hydrophilic white carbon is modified by double bonds so that it is loaded on the polymer through chemical bonds, thereby increasing the solubility of the thickening synergist in water, solving the problem that white carbon cannot be completely dissolved in water, and making it usable as a thickening agent for pesticide water, utilizing the high surface tension of white carbon to achieve a good thickening effect, using less auxiliary agent, and saving cost. Compared with conventional thickening agents, the thickening synergist of the present invention can use less auxiliary agent to achieve the same viscosity, and the prepared glyphosate and its composite water preparation still have a certain viscosity during the dilution spraying process, thereby increasing the adhesion between the liquid and plant leaves, preventing drift, and saving the amount of medicine.

[0013] The invention grafts cations and nano-white carbon black, and has a dual synergistic effect: 1. The glyphosate produced and its composite aqueous preparation can have a higher viscosity; and the molecular weight of the thickening synergist of the invention is 100 to 500 times that of the conventional emulsifier, and it still has a higher viscosity after being diluted with water during use, thereby increasing the adhesion of the liquid medicine on the plant surface and having a strong ability to resist rain erosion; 2. The polyamine group and the cationic group in the thickening synergist can provide better wetting and synergistic effects, and the polyamine monomer greatly increases the N content in the molecule, so that the drug effect is significantly improved.

[0014] The present invention selects unsaturated polyamine monomers for polymerization, which increases the steric hindrance of the monomers, increases the activation energy, is conducive to controlling the reaction speed, and is not easy to produce violent polymerization gel.

[0015] Furthermore, the preparation method of the unsaturated polyamine monomer is: use ethyleneamine and unsaturated diacid to carry out amidation reaction to obtain the unsaturated polyamine monomer.

[0016] Further, the ethyleneamine includes at least one of ethylenediamine, diethylenetriamine and triethylenetetramine.

[0017] Further, the unsaturated diacid includes any one of maleic acid, maleic anhydride and itaconic acid.

[0018] From the above description, it can be seen that the present invention uses ethyleneamine and unsaturated diacid to react to generate unsaturated polyamine monomers, which greatly increases the N content in the molecule and can improve the synergistic effect of the additive.

[0019] Furthermore, the amidation reaction is carried out in an inert gas, the reaction temperature is 140-160° C., and the reaction time is 4.5-5.5 h.

[0020] Furthermore, the molar ratio of ethyleneamine to unsaturated diacid is 1.8-2.2:1.

[0021] Furthermore, the preparation method of double bond modified fumed silica is as follows: after activating the hydrophilic fumed silica, add it into toluene, then add triethylamine and cool it to 4.5-5.5°C, add enoyl chloride dropwise until the pH is stable, then maintain the temperature for reaction for 2.5-3.5 hours, and after the reaction is completed, purify it to obtain the double bond modified fumed silica.

[0022] It can be seen from the above description that triethylamine is used as an acid binding agent.

[0023] From the above description, it can be seen that when white carbon black is traditionally used as a thickener, it is mainly used in formulations with milky white appearance, such as pesticide emulsions and suspensions. Since the water solubility of white carbon black itself is insufficient, it will affect the transparency of the product and is not suitable for use in pesticide aqueous solutions. The present invention double-bond-modified white carbon black and then polymerized, and white carbon black and hydrophilic unsaturated monomers can be copolymerized, and the hydrophilicity of other monomers is used to bring white carbon black into the water phase, thereby increasing the solubility of white carbon black in water, so that it can be used in pesticide aqueous solutions.

[0024] Furthermore, the specific surface area of ​​hydrophilic fumed silica is 100~380m 2 / g.

[0025] From the above description, it can be seen that the larger the specific surface area of ​​the hydrophilic fumed silica, the better the thickening effect.

[0026] Furthermore, the purification is specifically as follows: adding hydroquinone, heating to 110-130° C. and removing toluene under negative pressure.

[0027] Furthermore, the olefin chloride includes at least one of acryloyl chloride, methacryloyl chloride and methacryloyl chloride.

[0028] Furthermore, unsaturated polyamine monomers, double-bond modified fumed silica and unsaturated cationic monomers are added into deionized water, an inert gas is introduced, and then the temperature is raised to 60-70° C. and an initiator is added dropwise. After the addition is completed, the temperature is kept at 2.5-3.5 hours to obtain a thickening synergist.

[0029] From the above description, we can see that Furthermore, the molar ratio of the unsaturated polyamine monomer, the double-bond modified fumed silica and the unsaturated cationic monomer is 2:1:1.

[0030] Furthermore, the amount of initiator used is 0.3~1%.

[0031] Further, the unsaturated cationic monomer is any one of methacryloyloxyethyl trimethyl ammonium chloride, methacryloyloxy trimethyl ammonium chloride, acryloyloxyethyl trimethyl ammonium chloride, acryloyloxy trimethyl trimethyl ammonium chloride and (3-acrylamidopropyl) trimethyl ammonium chloride.

[0032] From the above description, it can be seen that high molecular cations can increase the molecular weight of thickening enhancers, and work together with white carbon black to have an excellent thickening effect. In the dilution spray process, they still have a certain viscosity, increasing the adhesion of the liquid on the leaves.

[0033] Another technical solution adopted by the present invention is: the thickening synergist is prepared by the preparation method of the thickening synergist suitable for the glyphosate compound water agent.

[0034] From the above description, it can be seen that the high molecular cationic loaded silica polymer in this scheme can improve the thickening effect very well, save costs with less additives, and still have a higher viscosity than the conventional preparation diluent after dilution with water, increase the adhesion of the agent on the plant leaves, have strong resistance to rain erosion, and have a significant synergistic effect.

[0035] Embodiment 1 of the present invention is: a method for preparing a thickening synergist suitable for a glyphosate compound aqueous solution, the steps are as follows: S1: 2.16 kg of ethylenediamine was added to the reactor, stirring was started, N2 was introduced, and 2.09 kg of butenedioic acid was slowly added in batches. With the addition of butenedioic acid, the reaction was exothermic to between 110 and 120 °C. After the exotherm ended, the temperature was raised to 150 °C and the reaction was kept at this temperature for 5 hours to obtain an unsaturated polyamine monomer, as shown in (Formula 1).

[0036] (Formula 1).

[0037] S2: Hydrophilic fumed silica (surface area 180m 2 / g, the hydroxyl content was determined by Grignard reagent titration method and was 3.5 / nm 2 ) was placed in a constant temperature drying oven at 150°C for activation for 6 hours, and then placed in a dryer to cool to room temperature for use; 2L of toluene dehydrated by molecular sieve was first added to a 5L reactor, and then a total of 500g of activated hydrophilic fumed silica was added in 5 times, and each batch of the reactor was sealed and stirred for 30 minutes; then 20ml of triethylamine dehydrated by distillation was added, the circulating chilled water was turned on, the temperature of the reactor was controlled at 5°C, and acryloyl chloride was slowly added dropwise; the pH value of the reactor was observed by an online pH meter, and the pH value gradually decreased as the reaction proceeded. When the pH value was stable, the addition of acryloyl chloride was stopped, and the temperature was maintained for reaction for 3 hours; after the reaction was completed, the material was transferred to a rotary evaporator, and 0.1% of the mass of hydroquinone was added to the material except toluene. After heating to 120°C and removing toluene under negative pressure, double-bond modified fumed silica was obtained, as shown in (Formula 2).

[0038] (Formula 2).

[0039] S3: Add 2L of deionized water to a 5L reactor, start stirring, add 1kg of unsaturated polyamine monomer, 0.57kg of double-bond modified fumed silica and 1.08kg of methacryloyloxyethyl trimethylammonium chloride (effective content 80%), start heating and introduce N2 for deoxygenation; then prepare 100mL of ammonium persulfate solution initiator with a mass fraction of 10% with deionized water, transfer the ammonium persulfate solution initiator to a constant pressure funnel, and when the reactor is heated to 65°C, slowly add the ammonium persulfate solution initiator dropwise, and control the addition time to 2h. After the addition is completed, keep warm for 3h, cool to 40°C, filter and package to obtain a white carbon black-loaded cationic polyamine polymer, see (Formula 3), recorded as thickening enhancer 1.

[0041] (Formula 3).

[0042] Embodiment 2 of the present invention is: a method for preparing a thickening synergist suitable for glyphosate compound water agent, the steps are as follows: S1: 3.34 kg of diethylenetriamine was added into a reactor, stirring was started, N2 was introduced, and 1.76 kg of maleic anhydride was slowly added in batches. With the addition of maleic anhydride, the reaction was exothermic to between 110 and 120°C. After the exotherm ended, the temperature was raised to 140°C and the reaction was kept at this temperature for 4.5 hours to obtain an unsaturated polyamine monomer.

[0043] S2: Hydrophilic fumed silica (surface area 100m 2 / g) was placed in a constant temperature drying oven at 150℃ for activation for 6h, and then placed in a desiccator to cool to room temperature for standby use; 2L of toluene dehydrated by molecular sieve was first added to a 5L reactor, and then a total of 500g of activated hydrophilic fumed silica was added in 5 times, and each batch of the reactor was sealed and stirred for 30min; then 20ml of triethylamine dehydrated by distillation was added, the circulating chilled water was turned on, the temperature of the reactor was controlled at 4.5℃, and methacryloyl chloride was slowly added dropwise; the pH value of the reactor was observed by an online pH meter, and the pH value gradually decreased as the reaction proceeded. When the pH value was stable, the addition of methacryloyl chloride was stopped, and the temperature was maintained for reaction for 2.5h; after the reaction was completed, the material was transferred to a rotary evaporator, and 0.1% of hydroquinone was added to the mass of the material except toluene, and the double-bond modified fumed silica was obtained after heating to 110℃ and removing toluene under negative pressure.

[0044] S3: Add 2L of deionized water to a 5L reactor, start stirring, add 1kg of unsaturated polyamine monomer, 0.57kg of double-bond modified fumed silica and 1.08kg of methacryloyltrimethylammonium chloride, start heating and introduce N2 for deoxygenation; then prepare 100mL of ammonium persulfate solution initiator with a mass fraction of 8% with deionized water, transfer the ammonium persulfate solution initiator to a constant pressure funnel, and when the reactor is heated to 60°C, slowly add the ammonium persulfate solution initiator dropwise, and control the addition time to 2h. After the addition is completed, keep warm for 2.5h, cool to 40°C, filter and package to obtain a white carbon black-loaded cationic polyamine polymer, recorded as thickener 2.

[0045] Embodiment 3 of the present invention is: a method for preparing a thickening synergist suitable for glyphosate compound water agent, the steps are as follows: S1: 5.79 kg of triethylenetetramine was added into a reactor, stirring was started, N2 was introduced, and 2.34 kg of itaconic acid was slowly added in batches. With the addition of itaconic acid, the reaction was exothermic to between 110 and 120°C. After the exotherm ended, the temperature was raised to 160°C and the reaction was kept at this temperature for 5.5 hours to obtain an unsaturated polyamine monomer.

[0046] S2: Hydrophilic fumed silica (surface area 380m 2 / g) was placed in a constant temperature drying oven at 150℃ for activation for 6h, and then placed in a desiccator to cool to room temperature for standby use; 2L of toluene dehydrated by molecular sieve was first added to a 5L reactor, and then a total of 500g of activated hydrophilic fumed silica was added in 5 times, and each batch of the reactor was sealed and stirred for 30min; then 20ml of triethylamine dehydrated by distillation was added, the circulating chilled water was turned on, the temperature of the reactor was controlled at 5.5℃, and methacryloyl chloride was slowly added dropwise; the pH value of the reactor was observed by an online pH meter, and the pH value gradually decreased as the reaction proceeded. When the pH value was stable, the addition of methacryloyl chloride was stopped, and the temperature was maintained for reaction for 3.5h; after the reaction was completed, the material was transferred to a rotary evaporator, and 0.1% of hydroquinone was added to the mass of the material except toluene, and the double-bond modified fumed silica was obtained after heating to 130℃ and removing toluene under negative pressure.

[0047] S3: Add 2L of deionized water to a 5L reactor, start stirring, add 1kg of unsaturated polyamine monomer, 0.57kg of double-bond modified fumed silica and 1.08kg of acryloyloxyethyltrimethylammonium chloride, start heating and introduce N2 for deoxygenation; then prepare 100mL of ammonium persulfate solution initiator with a mass fraction of 12% with deionized water, transfer the ammonium persulfate solution initiator to a constant pressure funnel, and when the reactor is heated to 70°C, slowly add the ammonium persulfate solution initiator dropwise, and control the addition time to 2h. After the addition is completed, keep warm for 3.5h, cool to 40°C, filter and package to obtain a white carbon black-loaded cationic polyamine polymer, recorded as thickener 3.

[0048] Comparative Example 1 of the present invention is: The difference between Comparative Example 1 and Example 1 is that thickening synergist A is obtained without adding white carbon black.

[0049] Comparative Example 2 of the present invention is: The only difference between Comparative Example 2 and Example 1 is that an equal molar amount of acrylamide is used to replace the unsaturated polyamine monomer of product S1 to obtain thickener synergist B.

[0050] Embodiment 4 of the present invention is: the thickening and enhancing agent prepared by the preparation method of embodiment 1.

[0051] According to the dosage of adjuvants in Table 1, Example 1, Example 2, Example 3, Comparative Example 1 and Comparative Example 2 and conventional adjuvants were respectively prepared into preparations consisting of 30wt% glyphosate ammonium salt, 2wt% 2,4 drops of acid and the remainder of water. The preparations were subjected to viscosity and efficacy tests. The viscosity test results are shown in Table 1, and the efficacy test results are shown in Table 2.

[0052] Table 1

[0053] It can be seen from Table 1 that, compared with commercial additives, the thickening and synergistic additive prepared by the present invention can obtain a higher viscosity at a smaller dosage and still has a higher viscosity after dilution.

[0054] According to the dosage of adjuvants in Table 1, 7 glyphosate ammonium salts + 2,4 drops of acid water were prepared, namely Ⅰ, Ⅱ, Ⅲ, Ⅳ, Ⅴ, Ⅵ, Ⅶ. The efficacy of the 7 samples was compared, the dilution multiple was 400 times, and the dosage was 80g / m 2 The blank (no pesticide) was numbered VIII. A total of eight treatments were set up in the experiment, and each treatment was repeated three times. The control test of weeds in vacant land was carried out in Niulanping Village, Lianjiang County, Fujian Province, with an area of ​​360 m 2 , set up 24 cells, each cell is 15 m 2 , clay loam, mainly composed of Bermuda grass, Setaria, Amaranthus, Echinochloa crus-galli, and Xanthium sibiricum. 4 and 10 days after application, the efficacy of the pesticide was visually inspected, but no statistics were made. 14 days after application, three points were randomly selected in each plot, each with a depth of 0.25 m 2 , a total of 0.75m 2 The number of various weeds was investigated and the control effect was calculated (the control effect is the percentage of weed reduction after 14 days of the sample). See Table 2.

[0055] Table 2

[0056] It can be seen from the efficacy data in Table 2 that the control effects and average control effects of the thickening and synergistic agents 1, 2 and 3 obtained in the present invention on various weeds are better than those of the conventional thickeners C-65 and KH-3865; the thickening and synergistic agent A obtained in Comparative Example 1 does not have white carbon black loaded in its molecular structure, so the thickening effect is reduced and the efficacy is also reduced; the thickening and synergistic agent A obtained in Comparative Example 2 uses acrylamide instead of unsaturated polyamine monomers, so the number of amine groups in the molecule is greatly reduced, and the efficacy is also significantly reduced.

[0057] In summary, the thickening synergist and preparation method thereof for glyphosate compound water agent provided by the present invention adopts ethyleneamine and unsaturated diacid dehydration to carry out amidation reaction to obtain unsaturated polyamine monomer; adopts hydrophilic fumed silica and acryloyl chloride to obtain double-bond modified fumed silica; polymerizes saturated polyamine monomer, double-bond modified fumed silica and methacryloyloxyethyl trimethylammonium chloride to obtain a white carbon black loaded cationic polyamine polymer. The synthesis method is simple to operate and easy to repeat. The prepared white carbon black loaded cationic polyamine polymer can be used as a thickening synergist for glyphosate compound water agent, has high solubility, excellent thickening effect, small amount of auxiliary agent, still has high viscosity after dilution with water, increases the adhesion of the liquid on the plant surface, and the polyamine group and cationic group can also provide good wetting and synergistic effect, significantly improving the efficacy.

[0058] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent transformations made using the specification of the present invention, or directly or indirectly applied in related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for preparing a thickening synergist suitable for glyphosate compound water, characterized in that: The following steps are involved: The unsaturated polyamine monomer, double-bond modified fumed silica and unsaturated cationic monomer are polymerized to obtain a silica-loaded cationic polyamine polymer, which is a thickening and synergist.

2. The method for preparing a thickening synergist suitable for glyphosate compound water according to claim 1, characterized in that: The preparation method of the unsaturated polyamine monomer comprises: carrying out an amidation reaction between ethyleneamine and an unsaturated diacid to obtain the unsaturated polyamine monomer.

3. The method for preparing a thickening synergist suitable for glyphosate compound water according to claim 2, characterized in that: The ethyleneamine includes at least one of ethylenediamine, diethylenetriamine and triethylenetetramine.

4. The method for preparing a thickening synergist suitable for glyphosate compound water according to claim 2, characterized in that: The amidation reaction is carried out in an inert gas, the reaction temperature is 140-160° C., and the reaction time is 4.5-5.5 h.

5. The method for preparing a thickening synergist suitable for glyphosate compound water according to claim 2, characterized in that: The molar ratio of the ethyleneamine to the unsaturated diacid is 1.8-2.2:

1.

6. The method for preparing a thickening synergist suitable for glyphosate compound water according to claim 1, characterized in that: The preparation method of the double-bond modified fumed silica is as follows: hydrophilic fumed silica is activated and then added to toluene, triethylamine is added and the temperature is lowered to 4.5-5.5° C., enoyl chloride is added dropwise until the pH value is stable, and then the temperature is maintained for reaction, and after the reaction is completed, the double-bond modified fumed silica is obtained after purification.

7. The method for preparing a thickening synergist suitable for glyphosate compound water according to claim 6, characterized in that: The specific surface area of ​​the hydrophilic fumed silica is 100-380 m 2 / g.

8. The method for preparing a thickening synergist suitable for glyphosate compound water according to claim 6, characterized in that: The olefin chloride includes at least one of acryloyl chloride, methacryloyl chloride and methacryloyl chloride.

9. The method for preparing a thickening synergist suitable for glyphosate compound water according to claim 1, characterized in that: The unsaturated polyamine monomer, double-bond modified fumed silica and unsaturated cationic monomer are added into deionized water, an inert gas is introduced, and then the temperature is raised to 60-70° C. and an initiator is added dropwise. After the addition is completed, the temperature is kept to react to obtain a thickening synergist.

10. A thickening synergist prepared by the method for preparing a thickening synergist suitable for a glyphosate compound aqueous solution according to any one of claims 1 to 9.

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