A foam inhibitor for pesticide suspending agent, its preparation method and application

Abstract

The present application belongs to the technical field of defoaming agents, and relates to a defoaming agent for pesticide suspensions, a preparation method and application thereof. The defoaming agent for pesticide suspensions has polyether long side chains, and the polyether long side chains are one or more than one; all the polyether long side chains are connected to a starter through C-O bonds or C-N bonds at the end of ethylene oxide structure units; and the other end of the polyether long side chains is grafted with heptamethyltrisiloxane. By controlling the ratio of EO units and PO units in the polyether branched chain, the defoaming agent can maintain the most suitable hydrophilic-lipophilic balance value, and can be more quickly adsorbed on the surface of the foam for defoaming. The defoaming agent is grafted with heptamethyltrisiloxane, the heptamethyltrisiloxane grafting increases the branched structure of the defoaming agent, and simultaneously reduces the surface tension, so that the defoaming agent molecules have higher water solubility and surface activity, and the application range of the defoaming agent is wider, and the defoaming rate is faster.

Description

Technical Field

[0001] This invention belongs to the field of defoamer technology, and relates to a defoaming agent for pesticide suspensions, its preparation method and application. Background Technology

[0002] During the processing and use of pesticide formulations, foam is easily generated when pesticide emulsions, suspensions, and other liquids containing surfactants are stirred, shaken, or subjected to impact. Foam generation not only increases reaction time and wastes raw materials but also affects product quality and efficacy. Therefore, finding a suitable defoamer is essential to address the foaming problem during pesticide processing. Currently, there are many types of pesticide defoamers, mainly including natural oil defoamers, polyether defoamers, and silicone-based defoamers.

[0003] Natural oil defoamers have the advantage of not contaminating raw materials, but during long-term storage, natural oils are prone to oxidation, making them difficult to store. Furthermore, their low defoaming and foam-suppressing efficiency limits their application, resulting in widespread use but poor performance.

[0004] Polyether defoamers are characterized by being non-toxic, non-irritating, dispersible quickly in water, and having strong foam-suppressing properties. Traditional polyether defoamers with higher alcohols, glycerol, and dipropylene glycol as initiators have poor foam-suppressing performance in pesticide suspension systems. The foam-suppressing property of defoamers is even more important in pesticide suspension systems. In recent years, hyperbranched defoamers have received increasing attention due to their excellent foam-suppressing properties.

[0005] Organosilicon defoamers, whose main component is dimethylsiloxane, suffer from poor dispersibility in solution due to its strong hydrophobicity, making them unsuitable for direct defoaming. They are typically compounded with hydrophobic fumed silica, emulsifiers, deionized water, and other additives to form emulsion-type organosilicon defoamers. These defoamers exhibit good defoaming performance but poor foam suppression. Chinese patent application number 202210225979.7 discloses an organosilicon defoamer for pesticides that offers efficient and rapid defoaming with a simple production process; however, it is prone to decomposition under acidic conditions and easily demulsifies during pesticide grinding, thus reducing its defoaming and foam suppression effects. Polyether-modified organosilicon defoamers possess a hyperbranched structure, low surface tension, and excellent defoaming and foam suppression performance. However, currently available polyether-modified organosilicon defoamers typically require compounding with emulsifiers, thickeners, and stabilizers, involving complex processes and making them unsuitable for grinding systems. Chinese patent application number 202211008110.3 discloses a high-efficiency polyether-modified organosilicon defoamer for pesticides, which is highly effective in defoaming, suppressing foam, and is resistant to high temperatures, acids, and alkalis. However, it cannot persistently suppress foam generation in pesticide suspension systems. Chinese patent application number 202410313662.8 discloses a mixed defoamer for pesticides, composed of dimethyl silicone oil and glycerol polyether, which can be reused multiple times. However, the glycerol polyether has a low degree of branching and limited foam suppression ability, only showing good foam suppression effects in some low-foaming pesticide systems. Summary of the Invention

[0006] The technical problem to be solved by this invention is to address the shortcomings of existing technologies by providing an antifoaming agent for pesticide suspensions, its preparation method, and its application. This invention provides a hyperbranched polyether-based antifoaming agent that can be directly applied to pesticide processing without emulsification or compounding, greatly reducing processing steps, while maintaining long-lasting and stable antifoaming performance during grinding.

[0007] Invention Concept: The defoamer for pesticide suspensions provided by this invention has a hyperbranched structure. Hyperbranched defoamer molecules have low intermolecular forces and lower surface tension. Simultaneously, the defoamer molecules can self-aggregate. These characteristics allow the defoamer to spread rapidly on the liquid film surface, providing sustained foam suppression and rapid defoaming. The initiator used in the preparation of the defoamer for pesticide suspensions in this invention has multiple active hydrogen atoms (-OH, -NH2, -NH-, etc.), which can react with ethylene oxide (EO) and propylene oxide (PO) to form multiple polyether branches, exhibiting a certain degree of hyperbranching. Furthermore, by controlling the ratio of EO to PO, the defoamer molecules maintain a hydrophilic-lipophilic balance in the pesticide suspension. Finally, the end is capped with intermediate A, increasing the hydrophobicity of the defoamer molecules, significantly reducing surface tension, and further improving the foam suppression and defoaming performance of the defoamer for pesticide suspensions.

[0008] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0009] This invention discloses an antifoaming agent for pesticide suspensions, wherein the antifoaming agent for pesticide suspensions has long polyether side chains, and there are one or more long polyether side chains; the ethylene oxide structural unit ends of all long polyether side chains are connected to the initiator through CO bonds or CN bonds; the structural formula of the antifoaming agent for pesticide suspensions is shown in Formula C:

[0010]

[0011] in,

[0012] e is the number of structural units in ethylene oxide, and e is an integer greater than or equal to 1;

[0013] f is the number of structural units in propylene oxide, and f is an integer greater than or equal to 4;

[0014]

[0015] The initiator contains hydroxyl and / or amino groups, and is linked to [a group] via a CO bond or a CN bond. Connected, where * represents the connection point;

[0016] R is an initiator group;

[0017] n is an integer from 1 to a, where a is the number of hydroxyl and / or amino groups in the initiator.

[0018] In some embodiments, preferably

[0019] Among them, the antifoaming agent for pesticide suspension, This is denoted as EO unit. This is denoted as PO unit.

[0020] In some embodiments, preferably, e is the number of structural units of ethylene oxide, and e is an integer from 1 to 50, more preferably an integer from 10 to 50.

[0021] In some embodiments, preferably, f is the number of structural units of propylene oxide, and f is an integer from 4 to 100, more preferably an integer from 20 to 100.

[0022] In some embodiments, the initiator is any one or a combination of several of the following: a polyhydroxy compound, a polyamino compound, a copolymer containing a polyamino group, and a copolymer containing a polyhydroxy group; preferably, the polyhydroxy compound is any one or a combination of several of the following: xylitol, mannitol, trehalose, mesobiose, polyglycerol, and polypentaerythritol; the polyamino compound is any one or a combination of several of the following: 2,4,5,6-tetraaminopyrimidine, spermine, and polyethyleneimine; the copolymer containing a polyamino group is a formaldehyde-phenol-triethylenetetramine copolymer; and the copolymer containing a polyhydroxy group is any one or a combination of two of the following: a copolymer of pentaerythritol and dimethylolpropionic acid, and a copolymer of xylitol and dimethylolpropionic acid.

[0023] In some embodiments, preferably, the initiator is any one or a combination of several of a polyhydroxy compound, a polyamino compound, and a copolymer containing a polyamino compound; the polyhydroxy compound is polyglycerol; the polyamino compound is polyethyleneimine; and the copolymer containing a polyamino compound is formaldehyde-phenol-triethylenetetramine copolymer.

[0024] The polyglycerol has a degree of polymerization ≥3, preferably 3, 6 or 10; the polypentaerythritol has a degree of polymerization ≥2; and the polyethyleneimine has a degree of polymerization ≥5, preferably 5.

[0025] Furthermore, the present invention discloses a method for preparing the above-mentioned antifoaming agent for pesticide suspensions, comprising the following steps:

[0026] (1) Mix the initiator, the first catalyst, and ethylene oxide, and control the system pressure to carry out the first polymerization reaction to synthesize polyether;

[0027] (2) After mixing the polyether with the bimetallic cyanide complex catalyst, the first part of propylene oxide is added, the system pressure is controlled, and after the reaction is initiated, the second part of propylene oxide is added to continue the second polymerization reaction to synthesize intermediate B.

[0028] (3) Mix intermediate B, the second catalyst, and intermediate A to carry out a coupling reaction to obtain an antifoaming agent for pesticide suspension.

[0029] Wherein, intermediate A is as shown in Formula A, intermediate B is as shown in Formula B, and the antifoaming agent for pesticide suspension is as shown in Formula C:

[0030]

[0031] in,

[0032] e is the number of structural units in ethylene oxide, and e is an integer greater than or equal to 1;

[0033] f is the number of structural units in propylene oxide, and f is an integer greater than or equal to 4;

[0034]

[0035] The initiator contains hydroxyl and / or amino groups, and is linked to [a group] via a CO bond or a CN bond. Connected, where * represents the connection point;

[0036] R is an initiator group;

[0037] n is an integer from 1 to a, where a is the number of hydroxyl and / or amino groups in the initiator.

[0038] In some embodiments, the initiator is any one or a combination of several of the following: a polyhydroxy compound, a polyamino compound, a copolymer containing a polyamino group, and a copolymer containing a polyhydroxy group; preferably, the polyhydroxy compound is any one or a combination of several of the following: xylitol, mannitol, trehalose, mesobiose, polyglycerol, and polypentaerythritol; the polyamino compound is any one or a combination of several of the following: 2,4,5,6-tetraaminopyrimidine, spermine, and polyethyleneimine; the copolymer containing a polyamino group is a formaldehyde-phenol-triethylenetetramine copolymer; and the copolymer containing a polyhydroxy group is a pentaerythritol. The catalyst is any one or a combination of two of the following: an alcohol-dimethylolpropionic acid copolymer and a xylitol-dimethylolpropionic acid copolymer; the first catalyst is any one or a combination of several of the following: potassium hydroxide, sodium hydroxide, sodium methoxide, sodium hydride, and dimethylamine; the bimetallic cyanide complex catalyst is any one or a combination of several of the following: Fe-Zn bimetallic cyanide complex catalyst, Zn-Co bimetallic cyanide complex catalyst, and Ni-Co bimetallic cyanide complex catalyst; the second catalyst is any one or a combination of several of the following: potassium hydroxide, sodium hydroxide, sodium methoxide, sodium hydride, and dimethylamine.

[0039] In some embodiments, preferably, the initiator is any one or a combination of several of a polyhydroxy compound, a polyamino compound, and a copolymer containing a polyamino compound; the polyhydroxy compound is polyglycerol; the polyamino compound is polyethyleneimine; and the copolymer containing a polyamino compound is formaldehyde-phenol-triethylenetetramine copolymer.

[0040] The polyglycerol has a degree of polymerization ≥3, preferably 3, 6 or 10; the polypentaerythritol has a degree of polymerization ≥2; and the polyethyleneimine has a degree of polymerization ≥5, preferably 5.

[0041] In some embodiments, preferably, the first catalyst is potassium hydroxide.

[0042] In some embodiments, preferably, the bimetallic cyanide complexing catalyst is an Fe-Zn bimetallic cyanide complexing catalyst (DMC).

[0043] In some embodiments, preferably, the second catalyst is potassium hydroxide.

[0044] In some embodiments, in step (1), the mass ratio of the initiator to the first catalyst is 1:(0.005~0.020); the pressure of the control system is 0.05Mpa~0.30Mpa; the reaction temperature of the first polymerization reaction is 105℃~135℃; and the first polymerization reaction is carried out under inert gas protection.

[0045] In some embodiments, preferably, in step (1), the mass ratio of the initiator to the first catalyst is 1:0.010.

[0046] In some embodiments, preferably, in step (1), the pressure of the control system is 0.05 MPa to 0.20 MPa, and more preferably 0.10 MPa.

[0047] In some embodiments, preferably, in step (1), the first polymerization reaction is carried out at a reaction temperature of 115°C to 135°C, and more preferably at 120°C.

[0048] In step (1), the time for the first polymerization reaction is until the pressure in the reaction system no longer changes, at which point the reaction ends.

[0049] In some embodiments, preferably, in step (1), the inert gas is nitrogen.

[0050] In step (1), the initiator and the first catalyst are premixed, and the mixture is heated to 90-120°C and held under pressure for 0.5-2 hours under vacuum and inert gas protection to remove moisture. Then it is mixed with ethylene oxide, and the system pressure is controlled to carry out the first polymerization reaction to synthesize polyether.

[0051] In step (1), after the reaction is completed, the unreacted raw materials are removed under vacuum, and the material is discharged when the temperature drops to 60℃~90℃. 1%~5% pure water (by weight of the raw materials) is added to the discharged raw materials, the pH is adjusted to 4.0~6.0 with phosphoric acid, 1%~5% magnesium silicate (by weight of the raw materials) is added, the mixture is stirred evenly, and after vacuum dehydration, it is filtered to obtain polyether.

[0052] In some embodiments, the ratio of the molar amount of active hydrogen in the initiator in step (1) to the molar amount of ethylene oxide in step (1) and the total molar amount of the first part of propylene oxide and the second part of propylene oxide in step (2) is 1:(2.0 to 20.0):(6.0 to 45.0).

[0053] In some embodiments, the mass of the bimetallic cyanide complex catalyst is 1 × 10⁻⁶ of the total mass of the initiator, ethylene oxide, the first part of propylene oxide, and the second part of propylene oxide. -5 ~6×10 -5 .

[0054] In some embodiments, preferably, the ratio of the molar amount of active hydrogen in the initiator in step (1) to the molar amount of ethylene oxide in step (1) and the total molar amount of the first part of propylene oxide and the second part of propylene oxide in step (2) is 1:(2.0-8.0):(7.0-20.0), and more preferably 1:(2.0-6.0):(7.5-16.0).

[0055] The active hydrogen in the initiator refers to the active hydrogen on -OH, -NH2, and -NH-.

[0056] In some embodiments, preferably, the mass of the bimetallic cyanide complex catalyst is 3 × 10⁻⁶ of the total mass of the initiator, ethylene oxide, the first portion of propylene oxide, and the second portion of propylene oxide. -5 .

[0057] In some embodiments, in step (2), the mass ratio of the first part of propylene oxide to the second part of propylene oxide is (0.5-3.5):(7-13); the pressure of the control system is 0.05 MPa to 0.30 MPa; the reaction temperature of the second polymerization reaction is 105°C to 135°C; and the second polymerization reaction is carried out under inert gas protection.

[0058] In some embodiments, preferably, in step (2), the pressure of the control system is 0.10 MPa; the reaction temperature of the second polymerization reaction is 125°C to 135°C, more preferably 130°C; and the inert gas is preferably nitrogen.

[0059] In step (2), the reaction initiation, i.e., the pressure drop within the reaction system, represents the initiation of the reaction.

[0060] In step (2), the second polymerization reaction ends when the pressure in the reaction system no longer changes.

[0061] In step (2), after the second polymerization reaction is completed, the unreacted raw materials are removed by vacuum, and when the temperature drops to 60℃~90℃, the material is discharged to obtain intermediate B.

[0062] In some embodiments, in step (3), the mass ratio of intermediate B and the second catalyst to intermediate A is 1.0:(0.006~0.020):(0.05~0.95); the coupling reaction is carried out at a temperature of 110℃~130℃ for 3~6h; the coupling reaction is carried out under inert gas protection.

[0063] In some embodiments, preferably, in step (3), the mass ratio of intermediate B and the second catalyst to intermediate A is 1.0:(0.010~0.015):(0.10~0.60).

[0064] In some embodiments, preferably, in step (3), the coupling reaction is carried out at a temperature of 120°C for 5 hours.

[0065] In some embodiments, preferably, in step (3), the inert gas is nitrogen.

[0066] The application of the aforementioned antifoaming agent in pesticide suspensions as an antifoaming agent in pesticides is also within the scope of protection of this invention.

[0067] Beneficial effects:

[0068] (1) Compared with traditional silicone defoamers, the product provided by the present invention does not require emulsification or compounding and can be directly applied to pesticide processing, which greatly reduces the operation process and can maintain stable defoaming performance during the grinding process.

[0069] (2) The foam-suppressing properties of defoamers are more important in the production of pesticide suspensions. The defoamer provided by this invention has multiple polyether branches, forming a hyperbranched structure, which makes it easier to penetrate the liquid film and destroy the stability of the adsorption layer.

[0070] (3) By controlling the ratio of EO units and PO units in the polyether branch chain, the present invention enables the defoamer to maintain a suitable hydrophilic-lipophilic balance value in the pesticide suspension system, which can effectively defoam and suppress foam.

[0071] (4) The present invention introduces heptamethyltrisiloxane. The grafting of heptamethyltrisiloxane increases the branched structure of the defoamer and reduces the surface tension, making the defoamer molecules have higher surface activity and further improving the foam suppression performance. Attached Figure Description

[0072] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, and the advantages of the present invention in the above and / or other aspects will become clearer.

[0073] Figure 1 The image shows the infrared spectrum of intermediate A prepared in this embodiment of the invention.

[0074] Figure 2 The infrared spectrum of the defoamer product prepared in Example 2 using pentaethylenehexamine as an initiator is shown.

[0075] Figure 3 The infrared spectrum of the defoamer product prepared in Example 3 using formaldehyde-phenol-triethylenetetramine copolymer as an initiator is shown.

[0076] Figure 4 The infrared spectrum of the defoamer product prepared using decaglycerol as an initiator in Example 1 is shown.

[0077] Figure 5 This is a photograph of the defoamer product prepared using decaglycerol as an initiator in Example 1.

[0078] Figure 6 The image shows a physical picture of the defoamer product prepared in Example 2 using pentaethylenehexamine as an initiator.

[0079] Figure 7 The image shows a physical picture of the defoamer product prepared in Example 3 using formaldehyde-phenol-triethylenetetramine copolymer as an initiator. Detailed Implementation

[0080] The present invention can be better understood from the following embodiments. However, those skilled in the art will readily understand that the descriptions in the embodiments are for illustrative purposes only and should not, and will not, limit the invention as detailed in the claims.

[0081] Unless otherwise specified, the experimental methods described in the following examples are conventional methods; unless otherwise specified, the reagents and materials are commercially available.

[0082] 1. The Fe-Zn bimetallic cyanide complex catalyst used in the embodiments of the present invention is DMC, Huaian Bad Technology Co., Ltd.

[0083] 2. The method for polymerization of the initiator with ethylene oxide, propylene oxide and propane in the embodiments and comparative examples of the present invention can refer to the method in Example 1 of Chinese Patent CN202111477270.8, or can be carried out according to the following method.

[0084] Example 1:

[0085] S1: Synthetic intermediate A

[0086]

[0087] Add 12 parts by weight of allyl glycidyl ether and 1 wt% isopropanol solution of chloroplatinic acid (0.1 parts by weight, i.e., containing 0.001 parts by weight of chloroplatinic acid) to a three-necked flask, purge with nitrogen, stir and heat to 90°C for activation for 30 min; after activation, add 20 parts by weight of heptamethyltrisiloxane to a constant pressure funnel, heat the reaction system to 120°C, open the funnel and add it dropwise to the three-necked flask, controlling the dropwise addition time to 30 min, and after the dropwise addition is completed, keep the reaction at the temperature for 5 h; after the reaction is completed, evaporate the solvent and unreacted raw material by rotary evaporation at 100°C to obtain intermediate A, which can be used directly in the next reaction without separation and purification.

[0088] S2: Mix 200 parts by weight of decaglycerol and 2 parts by weight of potassium hydroxide evenly, then add the mixture to a high-pressure reactor. Seal the reactor, evacuate to -0.1 MPa, and purge with nitrogen three times. Heat the reactor to 100°C and maintain the pressure for 1 hour to remove moisture. Then raise the temperature to 120°C, add 279 parts by weight of ethylene oxide, and control the system pressure at 0.1 MPa. Once the pressure no longer changes, remove unreacted raw materials under vacuum. When the temperature drops to 80°C, discharge the material. Add 3% by weight of pure water to the discharged material, adjust the pH to 5.5 with 85% phosphoric acid, add 2% by weight of magnesium silicate, mix evenly, dehydrate under vacuum, and filter to obtain refined polyether.

[0089] The refined polyether was placed in a high-pressure reactor, and 0.058 parts by weight of Fe-Zn bimetallic cyanide complex catalyst were added. The reactor was purged with nitrogen three times, stirred and heated to 130°C. 200 parts by weight of propylene oxide were added first, and the system pressure was controlled at 0.1 MPa. After the reaction was initiated (the reaction was initiated when the pressure dropped), 1270 parts by weight of propylene oxide were added. When the pressure no longer changed, the unreacted raw materials were removed under vacuum. When the temperature dropped to 80°C, the material was discharged to obtain intermediate B.

[0090] S3: Add 20 parts by weight of intermediate B and 0.24 parts by weight of potassium hydroxide to a three-necked flask, purge with nitrogen, stir and heat to 120°C. Then add 10.9 parts by weight of intermediate A to a constant pressure funnel, open the funnel, and control the dropping time for 30 minutes. After the dropping is complete, maintain the reaction at 120°C for 5 hours. After the reaction is complete, adjust the pH to neutral with phosphoric acid to obtain defoamer product 1, with a relative molecular mass M = 11434 and an intramolecular EO unit to PO unit ratio e:f = 1:4.

[0091] Intermediate A obtained in step S1 of this embodiment can be commercially available or prepared according to the experimental method described above. The infrared spectrum of the prepared intermediate A is shown below. Figure 1 As shown, 1258cm -1 915cm -1These are the absorption peaks for the symmetric and asymmetric stretching vibrations of the epoxy group, respectively, at 1670 cm⁻¹. -1 The C=C stretching vibration peak was significantly weakened, at 843 cm⁻¹. -1 The peak is the Si-CH3 vibrational absorption peak, 1055 cm⁻¹. -1 1077cm -1 The absorption peaks are due to the stretching vibrations of Si-O-Si, indicating that the intermediate has been successfully synthesized.

[0092] The infrared spectrum of the defoamer product prepared using decaglycerol as an initiator in this embodiment is as follows: Figure 4 As shown, 2970cm -1 2873cm -1 These are the asymmetric stretching vibration peaks of -CH3 and the symmetric stretching vibration peaks of -CH3, respectively, at 1455 cm⁻¹. -1 1374cm -1 The peak is the -CH3 bending vibration peak, 1258 cm⁻¹. -1 915cm -1 The symmetric and asymmetric stretching vibration peaks of the epoxy group disappear, 844 cm⁻¹ -1 This is the Si-CH3 vibrational peak, 10¹³ cm⁻¹. -1 The peak is the stretching vibration peak of Si-O-Si, at 1103 cm⁻¹. -1 1115cm -1 The peak of strong stretching vibration of COC indicates that product defoamer 1 was successfully synthesized.

[0093] The actual image of defoamer product 1 prepared using decaglycerol as the initiator in this embodiment is shown below. Figure 5 As shown.

[0094] Example 2:

[0095] S1: The experimental method is the same as step S1 in Example 1, and intermediate A is prepared.

[0096] S2: Mix 100 parts by weight of pentaethylenehexamine and 1 part by weight of potassium hydroxide evenly and add them to a high-pressure reactor. Seal the reactor, evacuate to -0.1 MPa, purge with nitrogen three times, heat the reactor to 100°C, and maintain the pressure for 1 hour to remove moisture. Then raise the temperature to 120°C, add 455 parts by weight of ethylene oxide, control the system pressure at 0.1 MPa, and wait until the pressure no longer changes. Remove unreacted raw materials under vacuum. When the temperature drops to 80°C, discharge the material. Add 3% by weight of pure water to the discharged material, adjust the pH to 5.5 with 85% phosphoric acid, add 2% by weight of magnesium silicate, mix evenly, dehydrate under vacuum, and filter to obtain refined polyether.

[0097] The refined polyether was placed in a high-pressure reactor, and 0.09 parts by weight of Fe-Zn bimetallic cyanide complex catalyst were added. The reactor was purged with nitrogen three times, stirred and heated to 130°C. First, 300 parts by weight of propylene oxide were added, and the system pressure was controlled at 0.1 MPa. After the reaction was initiated, 2100 parts by weight of propylene oxide were added. When the pressure no longer changed, the unreacted raw materials were removed under vacuum. When the temperature dropped to 80°C, the material was discharged to obtain intermediate B.

[0098] S3: Add 20 parts by weight of intermediate B and 0.22 parts by weight of potassium hydroxide to a three-necked flask, purge with nitrogen, stir and heat to 120°C, then add 7.8 parts by weight of intermediate A to a constant pressure funnel, open the funnel, control the dropping time for 30 minutes, and after the dropping is complete, keep the reaction at 120°C for 5 hours. After the reaction is complete, adjust the pH to neutral with phosphoric acid to obtain defoamer product 2, with a relative molecular mass M = 9561 and an intramolecular EO unit to PO unit ratio e:f = 1:4.

[0099] The infrared spectrum of the defoamer product prepared using pentaethylenehexamine as an initiator in this embodiment is as follows: Figure 2 As shown, 1258cm -1 915cm -1 The symmetric and asymmetric stretching vibration peaks of the epoxy group disappear, 844 cm⁻¹ -1 The peak is a Si-CH3 vibrational peak, 1055 cm⁻¹. -1 1073cm -1 The stretching vibration peak of Si-O-Si and 1114 cm⁻¹ -1 The COC stretching vibration peaks coincide at 2873 cm⁻¹. -1 The peak represents the symmetric stretching vibration of -CH3, at 1465 cm⁻¹. -1 The peak is the -CH2- bending vibration peak, at 1348 cm⁻¹. -1 The absorption peak of CN for stretching vibration confirms the synthesis of product 2, the defoamer.

[0100] The actual image of the defoamer product prepared using pentaethylenehexamine as the initiator in this embodiment is shown below. Figure 6 As shown.

[0101] Example 3:

[0102] S1: The experimental method is the same as step S1 in Example 1, and intermediate A is prepared.

[0103] S2: 100 parts by weight of formaldehyde-phenol-triethylenetetramine copolymer (molecular weight 270) and 1 part by weight of potassium hydroxide were mixed evenly and added to a high-pressure reactor. The reactor was sealed, evacuated to -0.1 MPa, purged with nitrogen three times, heated to 100°C, and held under pressure for 1 hour to remove moisture. Then, the temperature was raised to 120°C, and 392 parts by weight of ethylene oxide were added. The system pressure was controlled at 0.1 MPa. When the pressure no longer changed, unreacted raw materials were removed under vacuum. When the temperature dropped to 80°C, the material was discharged. 3% by weight of pure water was added to the discharged material, the pH was adjusted to 5.5 with 85% phosphoric acid, and 2% by weight of magnesium silicate was added. The mixture was mixed evenly, dehydrated under vacuum, and filtered to obtain refined polyether.

[0104] The refined polyether was placed in a high-pressure reactor, and 0.08 parts by weight of Fe-Zn bimetallic cyanide complex catalyst were added. The reactor was purged with nitrogen three times, stirred and heated to 130°C. First, 300 parts by weight of propylene oxide were added, and the system pressure was controlled at 0.1 MPa. After the reaction was initiated, 1763 parts by weight of propylene oxide were added. When the pressure no longer changed, the unreacted raw materials were removed under vacuum. When the temperature dropped to 80°C, the material was discharged to obtain intermediate B.

[0105] S3: Add 20 parts by weight of intermediate B and 0.21 parts by weight of potassium hydroxide to a three-necked flask, purge with nitrogen, stir and heat to 120°C, then add 5.8 parts by weight of intermediate A to a constant pressure funnel, open the funnel, control the dropping time for 30 minutes, and after the dropping is complete, keep the reaction at 120°C for 5 hours. After the reaction is complete, adjust the pH to neutral with phosphoric acid to obtain defoamer product 3, with a relative molecular mass M = 8926 and an intramolecular EO unit to PO unit ratio e:f = 1:4.

[0106] The infrared spectrum of the defoamer product prepared using formaldehyde-phenol-triethylenetetramine copolymer as an initiator in this embodiment is shown below. Figure 3 As shown, 1591cm -1 1458cm -1 The characteristic absorption peak of the benzene ring is at 2969 cm⁻¹. -1 2930cm -1 2872cm -1 1373cm -1 These are the asymmetric stretching vibration peaks of -CH3 and -CH2-, and the symmetric stretching vibration peak of -CH3, respectively, along with the bending vibration peak. 1258 cm⁻¹ -1 915cm -1 The symmetric and asymmetric stretching vibration peaks of the epoxy group disappear, 10¹³ cm⁻¹ -1 The peak is the stretching vibration peak of Si-O-Si, at 1110 cm⁻¹. -1C represents the stretching vibration peak of COC, at 1373 cm⁻¹. -1 The absorption peak of CN for stretching vibration confirms the synthesis of product 3, the defoamer.

[0107] The actual image of the defoamer product prepared using formaldehyde-phenol-triethylenetetramine copolymer as the initiator in this embodiment is shown below. Figure 7 As shown.

[0108] Example 4:

[0109] S1: The experimental method is the same as step S1 in Example 1, and intermediate A is prepared.

[0110] S2: Mix 300 parts by weight of decaglycerol and 3 parts by weight of potassium hydroxide evenly and add them to a high-pressure reactor. Seal the reactor, evacuate to -0.1 MPa, and purge with nitrogen three times. Heat the reactor to 100°C and maintain the pressure for 1 hour to remove moisture. Then raise the temperature to 120°C, add 628 parts by weight of ethylene oxide, and control the system pressure at 0.1 MPa. Once the pressure no longer changes, remove unreacted raw materials under vacuum. When the temperature drops to 80°C, discharge the material. Add 3% by weight of pure water to the discharged material, adjust the pH to 5.5 with 85% phosphoric acid, add 2% by weight of magnesium silicate, mix evenly, dehydrate under vacuum, and filter to obtain refined polyether.

[0111] The refined polyether was placed in a high-pressure reactor, and 0.09 parts by weight of Fe-Zn bimetallic cyanide complex catalyst were added. The reactor was purged with nitrogen three times, stirred and heated to 130°C. First, 300 parts by weight of propylene oxide were added, and the system pressure was controlled at 0.1 MPa. After the reaction was initiated, 1768 parts by weight of propylene oxide were added. When the pressure no longer changed, the unreacted raw materials were removed under vacuum. When the temperature dropped to 80°C, the material was discharged to obtain intermediate B.

[0112] S3: Add 20 parts by weight of intermediate B and 0.25 parts by weight of potassium hydroxide to a three-necked flask, purge with nitrogen, stir and heat to 120°C. Then add 10.7 parts by weight of intermediate A to a constant pressure funnel, open the funnel, and control the dropping time for 30 minutes. After the dropping is complete, maintain the reaction at 120°C for 5 hours. After the reaction is complete, adjust the pH to neutral with phosphoric acid to obtain defoamer product 4, with a relative molecular mass M = 11615 and an intramolecular EO unit to PO unit ratio e:f = 1:2.5.

[0113] Example 5:

[0114] S1: The experimental method is the same as step S1 in Example 1, and intermediate A is prepared.

[0115] S2: Mix 150 parts by weight of pentaethylenehexamine and 1.5 parts by weight of potassium hydroxide evenly and add them to a high-pressure reactor. Seal the reactor, evacuate to -0.1 MPa, and purge with nitrogen three times. Heat the reactor to 100°C and maintain the pressure for 1 hour to remove moisture. Then raise the temperature to 120°C, add 1025 parts by weight of ethylene oxide, and control the system pressure at 0.1 MPa. Once the pressure no longer changes, remove unreacted raw materials under vacuum. When the temperature drops to 80°C, discharge the material. Add 3% by weight of pure water to the discharged material, adjust the pH to 5.5 with 85% phosphoric acid, add 2% by weight of magnesium silicate, mix evenly, dehydrate under vacuum, and filter to obtain refined polyether.

[0116] The refined polyether was placed in a high-pressure reactor, and 0.14 parts by weight of Fe-Zn bimetallic cyanide complex catalyst were added. The reactor was purged with nitrogen three times, stirred and heated to 130°C. First, 300 parts by weight of propylene oxide were added, and the system pressure was controlled at 0.1 MPa. After the reaction was initiated, 3075 parts by weight of propylene oxide were added. When the pressure no longer changed, the unreacted raw materials were removed under vacuum. When the temperature dropped to 80°C, the material was discharged to obtain intermediate B.

[0117] S3: Add 20 parts by weight of intermediate B and 0.22 parts by weight of potassium hydroxide to a three-necked flask, purge with nitrogen, stir and heat to 120°C, then add 7.6 parts by weight of intermediate A to a constant pressure funnel, open the funnel, control the dropping time for 30 minutes, and after the dropping is complete, keep the reaction at 120°C for 5 hours. After the reaction is complete, adjust the pH to neutral with phosphoric acid to obtain defoamer product 5, with a relative molecular mass M = 9742 and an intramolecular EO unit to PO unit ratio e:f = 1:2.5.

[0118] Example 6:

[0119] S1: The experimental method is the same as step S1 in Example 1, and intermediate A is prepared.

[0120] S2: 150 parts by weight of formaldehyde-phenol-triethylenetetramine copolymer (molecular weight 270) and 1.5 parts by weight of potassium hydroxide were mixed evenly and added to a high-pressure reactor. The reactor was sealed, evacuated to -0.1 MPa, purged with nitrogen three times, heated to 100°C, and held under pressure for 1 hour to remove moisture. Then, the temperature was raised to 120°C, and 881 parts by weight of ethylene oxide were added. The system pressure was controlled at 0.1 MPa. When the pressure no longer changed, unreacted raw materials were removed under vacuum. When the temperature dropped to 80°C, the material was discharged. 3% by weight of pure water was added to the discharged material, the pH was adjusted to 5.5 with 85% phosphoric acid, and 2% by weight of magnesium silicate was added. The mixture was mixed evenly, dehydrated under vacuum, and filtered to obtain refined polyether.

[0121] The refined polyether was placed in a high-pressure reactor, and 0.118 parts by weight of Fe-Zn bimetallic cyanide complex catalyst were added. The reactor was purged with nitrogen three times, stirred and heated to 130°C. First, 300 parts by weight of propylene oxide were added, and the system pressure was controlled at 0.1 MPa. After the reaction was initiated, 2600 parts by weight of propylene oxide were added. When the pressure no longer changed, the unreacted raw materials were removed under vacuum. When the temperature dropped to 80°C, the material was discharged to obtain intermediate B.

[0122] S3: Add 20 parts by weight of intermediate B and 0.21 parts by weight of potassium hydroxide to a three-necked flask, purge with nitrogen, stir and heat to 120°C, then add 5.7 parts by weight of intermediate A to a constant pressure funnel, open the funnel, control the dropping time for 30 minutes, and after the dropping is complete, keep the reaction at 120°C for 5 hours. After the reaction is complete, adjust the pH to neutral with phosphoric acid to obtain defoamer product 6, with a relative molecular mass M = 9016 and an intramolecular EO unit to PO unit ratio e:f = 1:2.5.

[0123] Example 7:

[0124] S1: The experimental method is the same as step S1 in Example 1, and intermediate A is prepared.

[0125] S2: Mix 200 parts by weight of triglycerides and 2 parts by weight of potassium hydroxide evenly and add them to a high-pressure reactor. Seal the reactor, evacuate to -0.1 MPa, and purge with nitrogen three times. Heat the reactor to 100°C and maintain the pressure for 1 hour to remove moisture. Then raise the temperature to 120°C, add 587 parts by weight of ethylene oxide, and control the system pressure at 0.1 MPa. Once the pressure no longer changes, remove unreacted raw materials under vacuum. When the temperature drops to 80°C, discharge the material. Add 3% by weight of pure water to the discharged material, adjust the pH to 5.5 with 85% phosphoric acid, add 2% by weight of magnesium silicate, mix evenly, dehydrate under vacuum, and filter to obtain refined polyether.

[0126] The refined polyether was placed in a high-pressure reactor, and 0.116 parts by weight of Fe-Zn bimetallic cyanide complex catalyst were added. The reactor was purged with nitrogen three times, stirred and heated to 130°C. First, 300 parts by weight of propylene oxide were added, and the system pressure was controlled at 0.1 MPa. After the reaction was initiated, 2796 parts by weight of propylene oxide were added. When the pressure no longer changed, the unreacted raw materials were removed under vacuum. When the temperature dropped to 80°C, the material was discharged to obtain intermediate B.

[0127] S3: Add 20 parts by weight of intermediate B and 0.22 parts by weight of potassium hydroxide to a three-necked flask, purge with nitrogen, stir and heat to 120°C, then add 7.2 parts by weight of intermediate A to a constant pressure funnel, open the funnel, control the dropping time for 30 minutes, and after the dropping is complete, keep the reaction at 120°C for 5 hours. After the reaction is complete, adjust the pH to neutral with phosphoric acid to obtain defoamer product 7, with a relative molecular mass M = 6347 and an intramolecular EO unit to PO unit ratio e:f = 1:4.

[0128] Example 8:

[0129] S1: The experimental method is the same as step S1 in Example 1, and intermediate A is prepared.

[0130] S2: Mix 200 parts by weight of hexaglycerol and 2 parts by weight of potassium hydroxide evenly, then add the mixture to a high-pressure reactor. Seal the reactor, evacuate to -0.1 MPa, and purge with nitrogen three times. Heat the reactor to 100°C and maintain the pressure for 1 hour to remove moisture. Then raise the temperature to 120°C, add 458 parts by weight of ethylene oxide, and control the system pressure at 0.1 MPa. Once the pressure no longer changes, remove unreacted raw materials under vacuum. When the temperature drops to 80°C, discharge the material. Add 3% by weight of pure water to the discharged material, adjust the pH to 5.5 with 85% phosphoric acid, add 2% by weight of magnesium silicate, mix evenly, dehydrate under vacuum, and filter to obtain refined polyether.

[0131] The refined polyether was placed in a high-pressure reactor, and 0.09 parts by weight of Fe-Zn bimetallic cyanide complex catalyst were added. The reactor was purged with nitrogen three times, stirred and heated to 130°C. First, 300 parts by weight of propylene oxide were added, and the system pressure was controlled at 0.1 MPa. After the reaction was initiated, 2112 parts by weight of propylene oxide were added. When the pressure no longer changed, the unreacted raw materials were removed under vacuum. When the temperature dropped to 80°C, the material was discharged to obtain intermediate B.

[0132] S3: Add 20 parts by weight of intermediate B and 0.22 parts by weight of potassium hydroxide to a three-necked flask, purge with nitrogen, stir and heat to 120°C. Then add 7.58 parts by weight of intermediate A to a constant pressure funnel, open the funnel, and control the dropping time for 30 minutes. After the dropping is complete, maintain the reaction at 120°C for 5 hours. After the reaction is complete, adjust the pH to neutral with phosphoric acid to obtain defoamer product 8, with a relative molecular mass M = 9790 and an intramolecular EO unit to PO unit ratio e:f = 1:4.

[0133] Comparative Example 1:

[0134] S1: The experimental method is the same as step S1 in Example 1, and intermediate A is prepared.

[0135] S2: Mix 300 parts by weight of decaglycerol and 3 parts by weight of potassium hydroxide evenly and add them to a high-pressure reactor. Seal the reactor, evacuate to -0.1 MPa, and purge with nitrogen three times. Heat the reactor to 100°C and maintain the pressure for 1 hour to remove moisture. Then raise the temperature to 120°C, add 628 parts by weight of ethylene oxide, and control the system pressure at 0.1 MPa. Once the pressure no longer changes, remove unreacted raw materials under vacuum. When the temperature drops to 80°C, discharge the material. Add 3% by weight of pure water to the discharged material, adjust the pH to 5.5 with 85% phosphoric acid, add 2% by weight of magnesium silicate, mix evenly, dehydrate under vacuum, and filter to obtain refined polyether.

[0136] The refined polyether was placed in a high-pressure reactor, and 0.052 parts by weight of Fe-Zn bimetallic cyanide complex catalyst were added. The reactor was purged with nitrogen three times, stirred and heated to 130°C. 200 parts by weight of propylene oxide were added first, and the system pressure was controlled at 0.1 MPa. After the reaction was initiated, 627 parts by weight of propylene oxide were added. When the pressure no longer changed, the unreacted raw materials were removed under vacuum. When the temperature dropped to 80°C, the material was discharged to obtain intermediate B.

[0137] S3: Add 20 parts by weight of intermediate B and 0.31 parts by weight of potassium hydroxide to a three-necked flask, purge with nitrogen, stir and heat to 120°C. Then add 18.2 parts by weight of intermediate A to a constant pressure funnel, open the funnel, and control the dropping time for 30 minutes. After the dropping is complete, maintain the reaction at 120°C for 5 hours. After the reaction is complete, adjust the pH to neutral with phosphoric acid to obtain the comparative defoamer product 1, with a relative molecular mass M = 8477 and an intramolecular EO unit to PO unit ratio e:f = 1:1.

[0138] Comparative Example 2:

[0139] S1: The experimental method is the same as step S1 in Example 1, and intermediate A is prepared.

[0140] S2: Mix 150 parts by weight of pentaethylenehexamine and 1.5 parts by weight of potassium hydroxide evenly and add them to a high-pressure reactor. Seal the reactor, evacuate to -0.1 MPa, and purge with nitrogen three times. Heat the reactor to 100°C and maintain the pressure for 1 hour to remove moisture. Then raise the temperature to 120°C, add 1025 parts by weight of ethylene oxide, and control the system pressure at 0.1 MPa. Once the pressure no longer changes, remove unreacted raw materials under vacuum. When the temperature drops to 80°C, discharge the material. Add 3% by weight of pure water to the discharged material, adjust the pH to 5.5 with 85% phosphoric acid, add 2% by weight of magnesium silicate, mix evenly, dehydrate under vacuum, and filter to obtain refined polyether.

[0141] The refined polyether was placed in a high-pressure reactor, and 0.076 parts by weight of Fe-Zn bimetallic cyanide complex catalyst were added. The reactor was purged with nitrogen three times, stirred and heated to 130°C. 200 parts by weight of propylene oxide were added first, and the system pressure was controlled at 0.1 MPa. After the reaction was initiated, 1150 parts by weight of propylene oxide were added. When the pressure no longer changed, the unreacted raw materials were removed under vacuum. When the temperature dropped to 80°C, the material was discharged to obtain intermediate B.

[0142] S3: Add 20 parts by weight of intermediate B and 0.27 parts by weight of potassium hydroxide to a three-necked flask, purge with nitrogen, stir and heat to 120°C. Then add 13.8 parts by weight of intermediate A to a constant pressure funnel, open the funnel, and control the dropping time for 30 minutes. After the dropping is complete, maintain the reaction at 120°C for 5 hours. After the reaction is complete, adjust the pH to neutral with phosphoric acid to obtain the comparative defoamer product 2, with a relative molecular mass M = 6604 and an intramolecular EO unit to PO unit ratio e:f = 1:1.

[0143] Comparative Example 3:

[0144] S1: The experimental method is the same as step S1 in Example 1, and intermediate A is prepared.

[0145] S2: 150 parts by weight of formaldehyde-phenol-triethylenetetramine copolymer (molecular weight 270) and 1.5 parts by weight of potassium hydroxide were mixed evenly and added to a high-pressure reactor. The reactor was sealed, evacuated to -0.1 MPa, purged with nitrogen three times, heated to 100°C, and held under pressure for 1 hour to remove moisture. Then, the temperature was raised to 120°C, and 881 parts by weight of ethylene oxide were added. The system pressure was controlled at 0.1 MPa. When the pressure no longer changed, unreacted raw materials were removed under vacuum. When the temperature dropped to 80°C, the material was discharged. 3% by weight of pure water was added to the discharged material, the pH was adjusted to 5.5 with 85% phosphoric acid, and 2% by weight of magnesium silicate was added. The mixture was mixed evenly, dehydrated under vacuum, and filtered to obtain refined polyether.

[0146] The refined polyether was placed in a high-pressure reactor, and 0.066 parts by weight of Fe-Zn bimetallic cyanide complex catalyst were added. The reactor was purged with nitrogen three times, stirred and heated to 130°C. 200 parts by weight of propylene oxide were added first, and the system pressure was controlled at 0.1 MPa. After the reaction was initiated, 960 parts by weight of propylene oxide were added. When the pressure no longer changed, the unreacted raw materials were removed under vacuum. When the temperature dropped to 80°C, the material was discharged to obtain intermediate B.

[0147] S3: Add 20 parts by weight of intermediate B and 0.24 parts by weight of potassium hydroxide to a three-necked flask, purge with nitrogen, stir and heat to 120°C. Then add 10.2 parts by weight of intermediate A to a constant pressure funnel, open the funnel, and control the dropping time for 30 minutes. After the dropping is complete, maintain the reaction at 120°C for 5 hours. After the reaction is complete, adjust the pH to neutral with phosphoric acid to obtain the comparative defoamer product 3, with a relative molecular mass M = 5969 and an intramolecular EO unit to PO unit ratio e:f = 1:1.

[0148] Comparative Example 4:

[0149] 200 parts by weight of polyglycerol and 2 parts by weight of potassium hydroxide were mixed evenly and added to a high-pressure reactor. The reactor was sealed and evacuated to -0.1 MPa. Nitrogen was used to purge the reactor three times. The reactor was then heated to 100°C and held at pressure for 1 hour to remove moisture. The temperature was then raised to 120°C, and 279 parts by weight of ethylene oxide were added. The system pressure was controlled at 0.1 MPa. Once the pressure stabilized, unreacted raw materials were removed under vacuum. When the temperature dropped to 80°C, the material was discharged. 3% by weight of pure water was added to the discharged material, and the pH was adjusted to 5.5 with 85% phosphoric acid. 2% by weight of magnesium silicate was added, and the mixture was thoroughly mixed. After vacuum dehydration, the mixture was filtered to obtain refined polyether.

[0150] The refined polyether was placed in a high-pressure reactor, and 0.058 parts by weight of Fe-Zn bimetallic cyanide complex catalyst were added. The reactor was purged with nitrogen three times, stirred and heated to 130°C. 200 parts by weight of propylene oxide were added first, and the system pressure was controlled at 0.1 MPa. After the reaction was initiated, 1270 parts by weight of propylene oxide were added. When the pressure no longer changed, the unreacted raw materials were removed under vacuum. When the temperature dropped to 80°C, the material was discharged to obtain the comparative defoamer product 4, with a relative molecular mass M = 7395 and an intramolecular EO unit to PO unit ratio e:f = 1:4.

[0151] Comparative Example 5:

[0152] 100 parts by weight of pentaethylenehexamine and 1 part by weight of potassium hydroxide were mixed evenly and added to a high-pressure reactor. The reactor was sealed and evacuated to -0.1 MPa. Nitrogen was used to purge the reactor three times. The reactor was then heated to 100°C and held at pressure for 1 hour to remove moisture. The temperature was then raised to 120°C, and 455 parts by weight of ethylene oxide were added. The system pressure was controlled at 0.1 MPa. Once the pressure stabilized, unreacted raw materials were removed under vacuum. When the temperature dropped to 80°C, the material was discharged. 3% by weight of pure water was added to the discharged material, the pH was adjusted to 5.5 with 85% phosphoric acid, and 2% by weight of magnesium silicate was added. The mixture was thoroughly mixed, dehydrated under vacuum, and filtered to obtain refined polyether.

[0153] The refined polyether was placed in a high-pressure reactor, and 0.09 parts by weight of Fe-Zn bimetallic cyanide complex catalyst were added. The reactor was purged with nitrogen three times, stirred and heated to 130°C. First, 300 parts by weight of propylene oxide were added, and the system pressure was controlled at 0.1 MPa. After the reaction was initiated, 2100 parts by weight of propylene oxide were added. When the pressure no longer changed, the unreacted raw materials were removed under vacuum. When the temperature dropped to 80°C, the material was discharged to obtain the comparative defoamer product 5, with a relative molecular mass M = 6868 and an intramolecular EO unit to PO unit ratio e:f = 1:4.

[0154] Comparative Example 6:

[0155] 100 parts by weight of formaldehyde-phenol-triethylenetetramine copolymer (molecular weight 270) and 1 part by weight of potassium hydroxide were mixed evenly and added to a high-pressure reactor. The reactor was sealed, evacuated to -0.1 MPa, purged with nitrogen three times, heated to 100°C, and held under pressure for 1 hour to remove moisture. Then, the temperature was raised to 120°C, and 392 parts by weight of ethylene oxide were added. The system pressure was controlled at 0.1 MPa. When the pressure no longer changed, unreacted raw materials were removed under vacuum. When the temperature dropped to 80°C, the material was discharged. 3% by weight of pure water was added to the discharged material, the pH was adjusted to 5.5 with 85% phosphoric acid, and 2% by weight of magnesium silicate was added. The mixture was mixed evenly, dehydrated under vacuum, and filtered to obtain refined polyether.

[0156] The refined polyether was placed in a high-pressure reactor, and 0.08 parts by weight of Fe-Zn bimetallic cyanide complex catalyst were added. The reactor was purged with nitrogen three times, stirred and heated to 130°C. First, 300 parts by weight of propylene oxide were added, and the system pressure was controlled at 0.1 MPa. After the reaction was initiated, 1763 parts by weight of propylene oxide were added. When the pressure no longer changed, the unreacted raw materials were removed under vacuum. When the temperature dropped to 80°C, the material was discharged to obtain the comparative defoamer product 6, with a relative molecular mass M = 6906 and an intramolecular EO unit to PO unit ratio e:f = 1:4.

[0157] Comparative Example 7:

[0158] S1: The experimental method is the same as step S1 in Example 1, and intermediate A is prepared.

[0159] S2: 74.5 parts by weight of dipropylene glycol and 0.75 parts by weight of potassium hydroxide were mixed evenly and added to a high-pressure reactor. The reactor was sealed, evacuated to -0.1 MPa, and purged with nitrogen three times. The mixture was then heated to 100°C and held at pressure for 1 hour to remove moisture. The temperature was then raised to 120°C, and 881 parts by weight of ethylene oxide were added. The system pressure was controlled at 0.1 MPa. Once the pressure stabilized, unreacted raw materials were removed under vacuum. When the temperature dropped to 80°C, the material was discharged. 3% by weight of pure water was added to the discharged material, the pH was adjusted to 5.5 with 85% phosphoric acid, and 2% by weight of magnesium silicate was added. The mixture was thoroughly mixed, dehydrated under vacuum, and filtered to obtain refined polyether.

[0160] The refined polyether was placed in a high-pressure reactor, and 0.118 parts by weight of Fe-Zn bimetallic cyanide complex catalyst were added. The reactor was purged with nitrogen three times, stirred and heated to 130°C. First, 300 parts by weight of propylene oxide were added, and the system pressure was controlled at 0.1 MPa. After the reaction was initiated, 2600 parts by weight of propylene oxide were added. When the pressure no longer changed, the unreacted raw materials were removed under vacuum. When the temperature dropped to 80°C, the material was discharged to obtain intermediate B.

[0161] S3: Add 30 parts by weight of intermediate B and 0.26 parts by weight of potassium hydroxide to a three-necked flask, purge with nitrogen, stir and heat to 120°C, then add 2.9 parts by weight of intermediate A to a constant pressure funnel, open the funnel, control the dropping time for 30 minutes, and after the dropping is complete, keep the reaction at 120°C for 5 hours. After the reaction is complete, adjust the pH to neutral with phosphoric acid to obtain the comparative defoamer product 7, with a relative molecular mass M = 7623 and an intramolecular EO unit to PO unit ratio e:f = 1:2.5.

[0162] Comparative Example 8:

[0163] S1: The experimental method is the same as step S1 in Example 1, and intermediate A is prepared.

[0164] S2: Mix 51 parts by weight of glycerol and 0.5 parts by weight of potassium hydroxide evenly and add them to a high-pressure reactor. Seal the reactor, evacuate to -0.1 MPa, purge with nitrogen three times, heat to 100°C, and maintain pressure for 1 hour to remove moisture. Then raise the temperature to 120°C, add 881 parts by weight of ethylene oxide, control the system pressure at 0.1 MPa, and wait until the pressure no longer changes. Remove unreacted raw materials under vacuum. When the temperature drops to 80°C, discharge the material. Add 3% by weight of pure water to the discharged material, adjust the pH to 5.5 with 85% phosphoric acid, add 2% by weight of magnesium silicate, mix evenly, dehydrate under vacuum, and filter to obtain refined polyether.

[0165] The refined polyether was placed in a high-pressure reactor, and 0.118 parts by weight of Fe-Zn bimetallic cyanide complex catalyst were added. The reactor was purged with nitrogen three times, stirred and heated to 130°C. First, 300 parts by weight of propylene oxide were added, and the system pressure was controlled at 0.1 MPa. After the reaction was initiated, 2600 parts by weight of propylene oxide were added. When the pressure no longer changed, the unreacted raw materials were removed under vacuum. When the temperature dropped to 80°C, the material was discharged to obtain intermediate B.

[0166] S3: Add 30 parts by weight of intermediate B and 0.28 parts by weight of potassium hydroxide to a three-necked flask, purge with nitrogen, stir and heat to 120°C, then add 4.4 parts by weight of intermediate A to a constant pressure funnel, open the funnel, control the dropping time for 30 minutes, and after the dropping is complete, keep the reaction at 120°C for 5 hours. After the reaction is complete, adjust the pH to neutral with phosphoric acid to obtain the comparative defoamer product 8, with a relative molecular mass M = 7917 and an intramolecular EO unit to PO unit ratio e:f = 1:2.5.

[0167] Comparative Example 9:

[0168] The defoamer tested was silicone defoamer 7610, sourced from Jiangsu Qingyu Chemical Technology Co., Ltd.

[0169] Comparative Example 10:

[0170] The defoamer tested was silicone defoamer 7820, sourced from Jiangsu Qingyu Chemical Technology Co., Ltd.

[0171] Example 9: Foam Suppression Performance Test

[0172] (1) The defoamer products prepared in Examples 1-8 and Comparative Examples 1-10 were tested according to HG / T 4783-2014 "Fat Alcohol Emulsion Defoamers". The defoaming and foam-suppressing performance of the defoamer products on the ground pesticide suspension was tested using the cyclic bubbling method (the defoamer products prepared in Examples 1-8 and Comparative Examples 1-10 were used as defoamers, and the dosage was 1 wt% of the pesticide suspension; the specific formulation of the pesticide suspension is shown in Table 1). The change in foam height within 360s after the sample was added was recorded. The smaller the foam volume at 10s, the better the defoaming performance; the smaller the foam volume at 360s, the better the foam-suppressing performance. The specific data are shown in Tables 2 and 3. The dispersants SD-811 and SD-206 in Table 1 are both from Shanghai Shida Polymer Materials Co., Ltd.

[0173] Table 1. Amounts of raw materials, water, and additives used (total 100g)

[0174]

[0175] Table 2

[0176]

[0177]

[0178] Table 3

[0179]

[0180] (2) Add the technical grade pesticide (promethazine), adjuvants (dispersant SD-811, dispersant SD-206, ethylene glycol, magnesium aluminum silicate, xanthan gum), water, grinding beads (zirconia beads, diameter 1.6-1.8 mm, 150 g each time, 1.5 times the mass of the pesticide system), and defoamer (using the defoamer products prepared in Examples 1-8 and Comparative Examples 1-10, 1 g) to a ball mill jar and grind (the sample after grinding is a very viscous pesticide suspension with many fine foams). No defoamer was added to the blank group. Record the initial liquid level distance from the jar opening H1, and record the liquid level distance from the jar opening H2 after grinding. The foam height h during grinding can be calculated by the difference method (h = H1 - H2). The foam height is recorded as h1 after 1 hour of grinding; h2 after 3 hours of grinding; and h3 after 5 hours of grinding. The amounts of raw materials, water, and adjuvants are shown in Table 4. Specific defoaming and foam suppression data are shown in Table 5.

[0181] Table 4. Formulation of 50% Atrazine pesticide suspension concentrate (100g)

[0182]

[0183] Table 5

[0184]

[0185]

[0186] This invention provides an antifoaming agent for pesticide suspensions, its preparation method, and its application. Many methods and approaches exist for implementing this technical solution; the above description is merely a preferred embodiment. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this invention, and these improvements and modifications should also be considered within the scope of protection of this invention. All components not explicitly stated in this embodiment can be implemented using existing technologies.

Claims

1. A defoaming agent for pesticide suspension concentrates, characterized in that, The aforementioned defoaming agent for pesticide suspension has long polyether side chains, and there are one or more long polyether side chains; the ethylene oxide structural unit ends of all long polyether side chains are connected to the initiator through CO bonds or CN bonds; the structural formula of the aforementioned defoaming agent for pesticide suspension is shown in Formula C: in, e is the number of structural units in ethylene oxide, and e is an integer greater than or equal to 1; f is the number of structural units in propylene oxide, and f is an integer greater than or equal to 4; The initiator contains hydroxyl and / or amino groups, and is linked to [a group] via a CO bond or a CN bond. Connected, where * represents the connection point; R is an initiator group; n is an integer from 1 to a, where a is the number of hydroxyl and / or amino groups in the initiator.

2. The antifoaming agent for pesticide suspensions according to claim 1, characterized in that, 3. The antifoaming agent for pesticide suspensions according to claim 1, characterized in that, The initiator is any one or a combination of several of the following: a polyhydroxy compound, a polyamino compound, a copolymer containing a polyamino group, and a copolymer containing a polyhydroxy group; preferably, the polyhydroxy compound is any one or a combination of several of the following: xylitol, mannitol, trehalose, mesobiose, polyglycerol, and polypentaerythritol; the polyamino compound is any one or a combination of several of the following: 2,4,5,6-tetraaminopyrimidine, spermine, and polyethyleneimine; the copolymer containing a polyamino group is a formaldehyde-phenol-triethylenetetramine copolymer; and the copolymer containing a polyhydroxy group is any one or a combination of two of the following: a copolymer of pentaerythritol and dimethylolpropionic acid, and a copolymer of xylitol and dimethylolpropionic acid.

4. The method for preparing the antifoaming agent for pesticide suspensions according to claim 1, characterized in that, Includes the following steps: (1) Mix the initiator, the first catalyst, and ethylene oxide, and control the system pressure to carry out the first polymerization reaction to synthesize polyether; (2) After mixing the polyether with the bimetallic cyanide complex catalyst, the first part of propylene oxide is added, the system pressure is controlled, and after the reaction is initiated, the second part of propylene oxide is added to continue the second polymerization reaction to synthesize intermediate B. (3) Mix intermediate B, the second catalyst, and intermediate A to carry out a coupling reaction to obtain an antifoaming agent for pesticide suspension. Wherein, intermediate A is as shown in Formula A, intermediate B is as shown in Formula B, and the antifoaming agent for pesticide suspension is as shown in Formula C: in, e is the number of structural units in ethylene oxide, and e is an integer greater than or equal to 1; f is the number of structural units in propylene oxide, and f is an integer greater than or equal to 4; The initiator contains hydroxyl and / or amino groups, and is linked to [a group] via a CO bond or a CN bond. Connected, where * represents the connection point; R is an initiator group; n is an integer from 1 to a, where a is the number of hydroxyl and / or amino groups in the initiator.

5. The preparation method according to claim 4, characterized in that, The initiator is any one or a combination of several of the following: a polyhydroxy compound, a polyamino compound, a copolymer containing a polyamino group, and a copolymer containing a polyhydroxy group; preferably, the polyhydroxy compound is any one or a combination of several of the following: xylitol, mannitol, trehalose, mesobiose, polyglycerol, and polypentaerythritol; the polyamino compound is any one or a combination of several of the following: 2,4,5,6-tetraaminopyrimidine, spermine, and polyethyleneimine; the copolymer containing a polyamino group is a formaldehyde-phenol-triethylenetetramine copolymer; the copolymer containing a polyhydroxy group is a pentaerythritol and dihydroxy... The catalyst is any one or a combination of two of the following: methylpropionic acid copolymer and xylitol and dimethylolpropionic acid copolymer; the first catalyst is any one or a combination of several of the following: potassium hydroxide, sodium hydroxide, sodium methoxide, sodium hydride, and dimethylamine; the bimetallic cyanide complex catalyst is any one or a combination of several of the following: Fe-Zn bimetallic cyanide complex catalyst, Zn-Co bimetallic cyanide complex catalyst, and Ni-Co bimetallic cyanide complex catalyst; the second catalyst is any one or a combination of several of the following: potassium hydroxide, sodium hydroxide, sodium methoxide, sodium hydride, and dimethylamine.

6. The preparation method according to claim 4, characterized in that, In step (1), the mass ratio of the initiator to the first catalyst is 1:(0.005~0.020); the pressure of the control system is 0.05Mpa~0.30Mpa; the reaction temperature of the first polymerization reaction is 105℃~135℃; and the first polymerization reaction is carried out under inert gas protection.

7. The preparation method according to claim 4, characterized in that, The ratio of the molar amount of active hydrogen in the initiator in step (1) to the molar amount of ethylene oxide in step (1) and the total molar amount of the first part of propylene oxide and the second part of propylene oxide in step (2) is 1:(2.0~20.0):(6.0~45.0); The mass of the bimetallic cyanide complex catalyst is 1 × 10⁻⁶ of the total mass of the initiator, ethylene oxide, the first portion of propylene oxide, and the second portion of propylene oxide. -5 ~6×10 -5 .

8. The preparation method according to claim 4, characterized in that, In step (2), the mass ratio of the first part of propylene oxide to the second part of propylene oxide is (0.5-3.5):(7-13); the pressure of the control system is 0.05 MPa to 0.30 MPa; the reaction temperature of the second polymerization reaction is 105℃ to 135℃; the second polymerization reaction is carried out under inert gas protection.

9. The preparation method according to claim 4, characterized in that, In step (3), the mass ratio of intermediate B and the second catalyst to intermediate A is 1.0:(0.006~0.020):(0.05~0.95); the coupling reaction is carried out at a temperature of 110℃~130℃ for 3~6h; the coupling reaction is carried out under inert gas protection.

10. The application of the antifoaming agent for pesticide suspensions as described in any one of claims 1 to 3 in pesticides.

Images