A method for preparing a polyether-based foam control composition

Abstract

The invention relates to a process for the preparation of a polyether-based foam control composition from a polyether ester polymer, a branched polyether, a fatty alcohol polyether, a silica, a hydroxyl compound and an emulsifier. The foam control composition prepared by this process has excellent foam inhibition properties without affecting the compatibility compared to conventional non-silicone foam control compositions.

Description

Technical Field

[0001] This invention relates to a method for preparing a polyether-type foam control composition, belonging to the field of fine chemical technology. Technical Background

[0002] Foam is a common phenomenon in daily life. In industrial production processes, foam control agents are often used to eliminate or remove harmful air bubbles from the system. Currently, foam control agents are an indispensable fine chemical additive in industrial production processes.

[0003] In pressure-sensitive adhesive latex and waterproof emulsion systems, mineral oil-based foam control agents are favored, primarily because they have minimal impact on surface properties. The basic components of mineral oil-based foam control agents include mineral oil, hydrophobic particles, and emulsifiers. The hydrophobic particles are what actually cause defoaming or foam suppression, while the mineral oil acts as a carrier. The emulsifier mainly carries the dispersion formed by the mineral oil and hydrophobic particles into the water, allowing the hydrophobic particles to exert their excellent defoaming effect. CN101445760 describes a defoamer composed of organic hydrocarbons, ethylene bis-stearamide, and hydrophilic silica; CN101903074B describes a mineral oil defoamer composed of mineral oil, dispersant, and silica; of course, in addition to mineral oil, hydrophobic particles, and emulsifiers, other substances such as polysiloxanes and polyethers are sometimes added. For example, CN200710021825.1 and CN200610161576.1 contain hydrophobic polyethers or hydrophobic polyether silicone oils, all to enhance foam control. However, this may result in the surface properties of the application system being affected.

[0004] In actual industrial production, since adhesives are produced on a large scale and in a continuous manner, users have put forward more requirements for foam control agents. These requirements are not limited to defoaming speed, foam suppression performance and compatibility, etc.

[0005] The inventors first designed and synthesized a polyether ester polymer, and then combined it with substances such as branched polyether and fatty alcohol polyether. Through a large number of experiments, a foam control composition was screened out, which takes into account both foam suppression performance and compatibility. Summary of the Invention

[0006] This invention provides a method for preparing a polyether-type foam control composition. Compared with ordinary non-organosilicon foam control compositions, the foam control composition prepared by this method has excellent foam suppression performance without affecting compatibility.

[0007] The polyether-type foam control composition is made from polyether ester polymer, branched polyether, fatty alcohol polyether, silica, hydroxyl compound and emulsifier:

[0008] A. Polyether ester polymer

[0009] The polyether ester polymer is synthesized from polyether, adipic acid, and trimethylolpropane under acidic conditions, and the ratio of these reactants is as follows:

[0010] Adipic acid: 1 mol;

[0011] Trimethylolpropane: 0.9–1.1 mol;

[0012] Polyether: 5–15 mol;

[0013] Acidic catalyst: 0.4–1% of the total mass of adipic acid, trimethylolpropane, and polyether;

[0014] The polyether is a polymer formed by polymerizing fatty alcohols with 16 to 30 carbon atoms with ethylene oxide (EO) and / or propylene oxide (PO) under the action of an alkaline catalyst or a bimetallic catalyst.

[0015] The polyether has a molecular weight of 1000-3000; the alkaline catalyst for synthesizing the polyether is potassium hydroxide.

[0016] The preparation method of the polyether ester polymer is as follows:

[0017] Adipic acid, trimethylolpropane, and an acidic catalyst are added sequentially to a flask equipped with a thermometer, nitrogen protection, and a stirrer. The stirring is turned on, and the temperature is raised to 150–200°C for 1–3 hours. Then, polyether is added, and the reaction continues at 150–200°C for 2–6 hours until no water is generated. The mixture is then cooled to room temperature to obtain the polyether ester polymer.

[0018] The amount of the polyether ester polymer used is 45-65% of the total mass of the foam control composition.

[0019] B. Branched polyether

[0020] The structural formula of the branched polyether is as follows:

[0021]

[0022] In formula (Ⅰ), the subscripts a, b, c, d, and m represent the degree of polymerization, with a and c taking values ​​of 0 or 1–10, b and d taking values ​​of 5–20, and m taking values ​​of 1–10; R and R 1 It consists of hydrocarbon groups with 4 to 20 carbon atoms, including alkyl and aromatic hydrocarbons.

[0023] The amount of the branched polyether used is 15-30% of the total mass of the foam control composition.

[0024] C. Fatty alcohol polyether

[0025] The structural formula of the fatty alcohol polyether is as follows:

[0026] R 2 O(EO) e (PO) f H

[0027] (II)

[0028] R in equation (II) 2 It is an alkyl group with 6 to 30 carbon atoms. The subscripts e and f are the degree of polymerization of EO and PO, respectively. e is 0 or 1 to 20, and f is 1 to 30.

[0029] The amount of the fatty alcohol polyether used is 5-15% of the total mass of the foam control composition.

[0030] D. Silicon dioxide

[0031] The silica mentioned is an antifoaming unit in the foam control composition. Depending on the preparation method, silica is classified into precipitated silica and fumed silica. The silica mentioned is fumed hydrophobic silica with a specific surface area of ​​150–400 m². 2 / g, the hydrophobicity M, as tested by the methanol method, is 55-70%.

[0032] Hydrophobic silica is obtained by heating and stirring hydrophilic silica and a hydrophobic agent in a reaction vessel. The hydrophobic agent is selected from low-viscosity trimethylsiloxy-terminated polydimethylsiloxane, low-viscosity hydroxyl-terminated polydimethylsiloxane, hexamethyldisilazane, hexamethyldisilazane, dimethyldiethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, trimethylchlorosilane, dimethyldichlorosilane, methyltrichlorosilane, tetrachlorosilane, stearic acid, tetradecyl alcohol, hexadecyl alcohol, octadecyl alcohol, stearyl alcohol, octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, and hexamethylcyclotrisiloxane. The hydrophobic agent of this invention is a fatty alcohol with 14 to 18 carbon atoms.

[0033] The amount of silica used is 3-8% of the total mass of the foam control composition.

[0034] E. Hydroxyl compounds

[0035] The hydroxyl compound refers to a compound containing hydroxyl groups composed of carbon, hydrogen, and oxygen elements, selected from ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol, glycerol, butanol, pentanol, hexanol, octanol, and diethylene glycol monobutyl ether.

[0036] The amount of the hydroxyl compound used is 5-15% of the total mass of the foam control composition.

[0037] F. Emulsifiers

[0038] The emulsifier is a nonionic surfactant, including nonylphenol polyoxyethylene ether, octylphenol polyoxyethylene ether, lauric acid polyoxyethylene ether, oleic acid polyoxyethylene ether, lauryl alcohol polyoxyethylene ether, octyl alcohol polyoxyethylene ether, isooctyl alcohol polyoxyethylene ether, isodecyl alcohol polyoxyethylene ether, isotridecyl alcohol polyoxyethylene ether, hexadecyl alcohol polyoxyethylene ether, octadecyl alcohol polyoxyethylene ether, oleyl alcohol polyoxyethylene ether, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, and sorbitan monostearate. Oleate, sorbitan tristearate, sorbitan trioleate, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan monooleate, polyoxyethylene sorbitan monooleate, polyoxyethylene sorbitan tristearate, polyoxyethylene oleate polyoxyethylene ether, polyoxyethylene oleate polyoxyethylene polyoxypropylene ether, castor oil polyoxyethylene ether, castor oil polyoxyethylene polyoxypropylene ether.

[0039] The amount of emulsifier used is 3-10% of the total mass of the foam control composition.

[0040] The preparation method of the foam control composition is as follows:

[0041] Add the hydroxyl compound to the container, start stirring, and add silica in batches while controlling the speed at 500-6000 rpm. At this time, a transparent silica dispersion is obtained.

[0042] At room temperature, add polyether ester polymer, branched polyether and fatty alcohol polyether to another container, turn on the stirrer and raise the temperature to 50-80°C, set the speed to 600-3000 rpm, slowly add silica dispersion, and after all silica dispersion has been added, increase the speed to 1000-5000 rpm and keep at 120-150°C for 0.5-3 hours. Then add emulsifier, stir evenly and cool to room temperature to obtain foam control composition. Detailed Implementation

[0043] The selection of polyether ester polymers in the examples is shown in Tables 1 and 2:

[0044] Adipic acid (AA), trimethylolpropane (TMP), and an acidic catalyst are added sequentially to a flask equipped with a thermometer, nitrogen protection, and a stirrer. The stirring is started, and the temperature is raised to 150–200°C for 1–3 hours. Then, polyether is added, and the reaction continues at 150–200°C for 2–6 hours until no water is generated. The mixture is then cooled to room temperature to obtain the polyether ester polymer.

[0045] Table 1 Types of Polyethers

[0046] Types of polyethers Number of carbon atoms in the initiator EO / PO molar ratio catalyst P1 16 17 / 0 potassium hydroxide P2 18 5 / 22 Bimetallic catalyst P3 22 6 / 26 Bimetallic catalyst P4 24 22 / 22 Bimetallic catalyst P5 30 0 / 43 Bimetallic catalyst

[0047] Table 2 Synthesis process conditions for polyether ester polymers

[0048]

[0049] Example 1

[0050] Add 5 parts diethylene glycol to a container, start stirring, and while maintaining a speed of 500–6000 rpm, add 3 parts silica (with a specific surface area of ​​150 m²) in batches. 2 / g, methanol value M=63%, hydrophobic treatment agent is n-tetradecyl alcohol), at this time a transparent silica dispersion is obtained;

[0051] At room temperature, add 64 parts of polyether ester polymer A1 and 15 parts of branched polyether (subscripts a=0, b=15, c=3, d=5, m=6, substituent R) to another container. 1 It is an alkyl group with 4 carbon atoms, where R is phenyl) and 10 parts of fatty alcohol polyether (subscript e=0, f=15, substituent R) 2 (If the number of carbon atoms is 6), turn on the stirrer and raise the temperature to 80°C. Set the speed to 2000 rpm and slowly add silica dispersion. After all the silica dispersion has been added, increase the speed to 2500 rpm and keep it at 140°C for 2 hours. Then add 3 parts of oleic acid polyoxyethylene ether (7), stir evenly and cool to room temperature to obtain foam control composition K1.

[0052] Example 2

[0053] Add 15 parts of diethylene glycol monobutyl ether to a container, start stirring, and while maintaining a speed of 6000 rpm, add 8 parts of silica (with a specific surface area of ​​380 m²) in batches. 2 / g, methanol value M=70%, hydrophobic treatment agent is n-octadecyl alcohol), at this time a transparent silica dispersion is obtained;

[0054] At room temperature, add 45 parts of polyether ester polymer A3 and 22 parts of branched polyether (subscripts a=1, b=5, c=0, d=20, m=1, substituent R) to another container. 1 It is an alkyl group with 20 carbon atoms, where R is an alkyl group with 4 carbon atoms) and 5 parts of fatty alcohol polyether (subscript e=1, f=30, substituent R) 2 (If the number of carbon atoms is 30), turn on the stirrer and raise the temperature to 50°C. Set the speed to 3000 rpm and slowly add 10 parts of silica dispersion. After all the silica dispersion has been added, increase the speed to 1000 rpm and keep it at 120°C for 0.5 hours. Then add 2 parts of Tween 80 and 3 parts of octanol polyoxyethylene ether (8), stir evenly and cool to room temperature to obtain foam control composition K2.

[0055] Example 3

[0056] Add 10 parts butanol to a container, start stirring, and while maintaining a speed of 1300 rpm, add 5 parts silica (with a specific surface area of ​​220 m²) in batches. 2 / g, methanol value M=55%, hydrophobic treatment agent is cetyl alcohol), at this time a transparent silica dispersion is obtained;

[0057] At room temperature, add 45 parts of polyether ester polymer A5 and 30 parts of branched polyether (subscripts a=10, b=20, c=10, d=14, m=10, substituent R) to another container. 1 It is an alkyl group with 12 to 14 carbon atoms, where R is an alkyl group with 20 carbon atoms) and 5 parts of fatty alcohol polyether (subscript e = 20, f = 1, substituent R). 2 (If the carbon number is 18), turn on the stirrer and raise the temperature to 68°C. Set the speed to 600 rpm and slowly add the silica dispersion. After all the silica dispersion has been added, increase the speed to 5000 rpm and keep it at 150°C for 3 hours. Then add 5 parts of fatty alcohol polyoxyethylene ether (21), stir evenly and cool to room temperature to obtain the foam control composition K3.

[0058] Example 4

[0059] Add 12 parts octanol to a container, start stirring, and while maintaining a speed of 4500 rpm, add 3 parts silica (with a specific surface area of ​​280 m²) in batches. 2 / g, methanol value M=59%, hydrophobic treatment agent is tetradecyl alcohol), at this time a transparent silica dispersion is obtained;

[0060] At room temperature, add 50 parts of polyether ester polymer A2 and 15 parts of branched polyether (subscripts a=5, b=8, c=1, d=8, m=7, substituent R) to another container. 1 It is an alkyl group with 10 carbon atoms (R is an alkyl group with 10 carbon atoms) and 15 parts of fatty alcohol polyether (subscript e=10, f=12, substituent R) 2 (The carbon number is 16). Turn on the stirrer and raise the temperature to 55°C. Set the speed to 2400 rpm and slowly add the silica dispersion. After all the silica dispersion has been added, increase the speed to 3500 rpm and keep it at 127°C for 1.5 hours. Then add 5 parts of AEO-8, stir evenly and cool to room temperature to obtain the foam control composition K4.

[0061] Example 5

[0062] Add 8 parts ethylene glycol to a container, start stirring, and while maintaining a speed of 3200 rpm, add 8 parts silica (with a specific surface area of ​​180 m²) in batches.2 / g, methanol value M=65%, hydrophobic treatment agent is octadecyl alcohol), at this time a transparent silica dispersion is obtained;

[0063] At room temperature, add 47 parts of polyether ester polymer A4 and 19 parts of branched polyether (subscripts a=6, b=14, c=6, d=6, m=5, substituent R) to another container. 1 It is an alkyl group with 12 to 14 carbon atoms (R is an alkyl group with 12 to 14 carbon atoms) and 15 parts of fatty alcohol polyether (subscript e=10, f=2, substituent R) 2 (The carbon number is 12), turn on the stirrer and raise the temperature to 78°C. Set the speed to 2500 rpm and slowly add the silica dispersion. After all the silica dispersion has been added, increase the speed to 3800 rpm and keep it at 138°C for 2.5 hours. Then add 3 parts of isomeric tridecyl alcohol polyoxyethylene ether (10), stir evenly and cool to room temperature to obtain the foam control composition K5.

[0064] Comparative Example 1 (Removal of polyether ester polymer)

[0065] Add 8 parts ethylene glycol to a container, start stirring, and while maintaining a speed of 3200 rpm, add 8 parts silica (with a specific surface area of ​​180 m²) in batches. 2 / g, methanol value M=65%, hydrophobic treatment agent is octadecyl alcohol), at this time a transparent silica dispersion is obtained;

[0066] At room temperature, 66 parts of branched polyether (subscripts a=6, b=14, c=6, d=6, m=5, substituent R) were added to another container. 1 It is an alkyl group with 12 to 14 carbon atoms (R is an alkyl group with 12 to 14 carbon atoms) and 15 parts of fatty alcohol polyether (subscript e=10, f=2, substituent R) 2 (The carbon number is 12), turn on the stirrer and raise the temperature to 78°C. Set the speed to 2500 rpm and slowly add the silica dispersion. After all the silica dispersion has been added, increase the speed to 3800 rpm and keep it at 138°C for 2.5 hours. Then add 3 parts of isomeric tridecyl alcohol polyoxyethylene ether (10), stir evenly and cool to room temperature to obtain the foam control composition K51.

[0067] Comparative Example 2 (Removal of Branched Polyether)

[0068] Add 8 parts ethylene glycol to a container, start stirring, and while maintaining a speed of 3200 rpm, add 8 parts silica (with a specific surface area of ​​180 m²) in batches. 2 / g, methanol value M=65%, hydrophobic treatment agent is octadecyl alcohol), at this time a transparent silica dispersion is obtained;

[0069] At room temperature, add 66 parts of polyether ester polymer A4 and 15 parts of fatty alcohol polyether (subscript e=10, f=2, substituent R) to another container. 2 (The carbon number is 12), turn on the stirrer and raise the temperature to 78°C. Set the speed to 2500 rpm and slowly add the silica dispersion. After all the silica dispersion has been added, increase the speed to 3800 rpm and keep it at 138°C for 2.5 hours. Then add 3 parts of isomeric tridecyl alcohol polyoxyethylene ether (10), stir evenly and cool to room temperature to obtain the foam control composition K52.

[0070] Comparative Example 3 (Removal of polyether ester polymer and branched polyether)

[0071] Add 8 parts ethylene glycol to a container, start stirring, and while maintaining a speed of 3200 rpm, add 8 parts silica (with a specific surface area of ​​180 m²) in batches. 2 / g, methanol value M=65%, hydrophobic treatment agent is octadecyl alcohol), at this time a transparent silica dispersion is obtained;

[0072] At room temperature, add 81 parts of fatty alcohol polyether (subscript e=10, f=2, substituent R) to another container. 2 (The sample contains 12 carbon atoms). Start the stirring and raise the temperature to 78°C. Set the stirring speed to 2500 rpm and slowly add the silica dispersion. After all the silica dispersion has been added, increase the stirring speed to 3800 rpm and maintain the temperature at 138°C for 2.5 hours. Then add 3 parts...

[0073] Isomeric tridecyl alcohol polyoxyethylene ether (10) was stirred evenly and cooled to room temperature to obtain foam control composition K53.

[0074] Comparative Example 4 (using polyether ester polymer instead of fatty alcohol polyether)

[0075] Add 8 parts ethylene glycol to a container, start stirring, and while maintaining a speed of 3200 rpm, add 8 parts silica (with a specific surface area of ​​180 m²) in batches. 2 / g, methanol value M=65%, hydrophobic treatment agent is octadecyl alcohol), at this time a transparent silica dispersion is obtained;

[0076] At room temperature, add 62 parts of polyether ester polymer A4 and 19 parts of branched polyether (subscripts a=6, b=14, c=6, d=6, m=5, substituent R) to another container. 1R is an alkyl group with 12 to 14 carbon atoms. Turn on the stirrer and raise the temperature to 78°C. Set the speed to 2500 rpm and slowly add the silica dispersion. After all the silica dispersion has been added, increase the speed to 3800 rpm and keep it at 138°C for 2.5 hours. Then add 3 parts of isomeric tridecyl alcohol polyoxyethylene ether (10), stir evenly and cool to room temperature to obtain the foam control composition K54.

[0077] Example 6

[0078] Add 10 parts triethylene glycol to a container, start stirring, and while maintaining a speed of 3200 rpm, add 4 parts silica (with a specific surface area of ​​210 m²) in batches. 2 / g, methanol value M=60%, hydrophobic treatment agent is cetyl alcohol), at this time a transparent silica dispersion is obtained;

[0079] At room temperature, add 25 parts of polyether ester polymer A4, 26 parts of polyether ester polymer A5, and 8 parts of branched polyether (subscripts a=5, b=5, c=5, d=5, m=7, substituent R) to another container. 1 It is an alkyl group with 8 carbon atoms, where R is an alkyl group with 8 carbon atoms), 7 parts of branched polyether (subscripts a=10, b=5, c=10, d=5, m=6, substituent R 1 It is an alkyl group with 6 carbon atoms (R is an alkyl group with 6 carbon atoms) and 12 parts of fatty alcohol polyether (subscript e=5, f=25, substituent R) 2 (The carbon atoms are 16-18). Start the stirring and raise the temperature to 66°C. Set the stirring speed to 1800 rpm and slowly add the silica dispersion. After all the silica dispersion has been added, increase the stirring speed to 2800 rpm and maintain the temperature at 128°C for 2 hours. Then add 8 parts of castor oil polyoxyethylene ether (12), stir evenly, and cool to room temperature to obtain the foam control composition K6. Comparative Example 5 (based on Example 6)

[0080] Add 10 parts triethylene glycol to a container, start stirring, and while maintaining a speed of 3200 rpm, add 4 parts silica (with a specific surface area of ​​210 m²) in batches. 2 / g, methanol value M=60%, hydrophobic treatment agent is cetyl alcohol), at this time a transparent silica dispersion is obtained;

[0081] At room temperature, add 51 parts of polyether ester polymer A5 and 15 parts of branched polyether (subscripts a=5, b=5, c=5, d=5, m=7, substituent R) to another container. 1 It is an alkyl group with 8 carbon atoms (R is an alkyl group with 8 carbon atoms) and 12 parts of fatty alcohol polyether (subscript e=5, f=25, substituent R) 2(The carbon number is 16-18), turn on the stirrer and raise the temperature to 66°C. Set the speed to 1800 rpm and slowly add the silica dispersion. After all the silica dispersion has been added, increase the speed to 2800 rpm and keep it at 128°C for 2 hours. Then add 8 parts of castor oil polyoxyethylene ether (12), stir evenly and cool to room temperature to obtain the foam control composition K61.

[0082] Performance testing:

[0083] 1. Test medium:

[0084] Acrylic pressure-sensitive latex was used as the test medium.

[0085] 2. Foam control performance:

[0086] Add 100g of emulsion and 0.06g of foam control agent sample to a beaker, disperse at 600rpm for 5min, then pour into a 500ml graduated cylinder, place an air aerator inside, select a flow rate of 100mL / min, and record the foam level after 2min. Higher foam levels indicate poorer foam control performance.

[0087] 3. Comparison of surface properties:

[0088] Take 1g of the above-mentioned aeration mixture and coat it onto a corona-electrode membrane using a 40-micron wire rod. Compare the pinholes on the resulting film. The more pinholes, the worse the compatibility.

[0089] 4. Test Results:

[0090] The test results are shown in Table 3 below:

[0091] Table 3 Comparison of foam control performance and compatibility of different samples

[0092] sample Foam graduations / mL Number of shrinkage holes / pieces K1 290 1 K2 280 1 K3 285 1 K4 295 1 K5 290 2 K51 280 14 K52 280 16 K53 240 >20 K54 320 1 K6 280 1 K61 280 3

[0093] The data in the table above shows that:

[0094] (1) All K1 to K5 exhibit excellent foam control performance and compatibility;

[0095] (2) By comparing K5 with K51, K52, K53 and K54, it can be seen that polyether ester polymers and branched polyethers contribute well to compatibility, while fatty alcohol polyethers have a good defoaming effect.

[0096] (3) By comparing K6 and K61, it can be seen that the combination of multiple polyether ester polymers and multiple branched polyethers is more conducive to compatibility than the combination of a single polyether ester polymer and a branched polyether.

[0097] Therefore, the foam control composition of this invention has multiple functions, such as long foam suppression time and good compatibility.

Claims

1. A polyether-based foam control composition, characterized in that, The polyether-type foam control composition is made from polyether ester polymer, branched polyether, fatty alcohol polyether, silica, hydroxyl compound and emulsifier: A. Polyether ester polymer The polyether ester polymer is polymerized from polyether, adipic acid, and trimethylolpropane under acidic conditions; The polyether is a polymer formed by polymerizing fatty alcohols with 16 to 30 carbon atoms with ethylene oxide (EO) and / or propylene oxide (PO) in the presence of KOH or a bimetallic catalyst. The amount of the polyether ester polymer used is 45-65% of the total mass of the foam control composition; B. Branched polyether, wherein the structural formula of the branched polyether is as follows: In formula (Ⅰ), the subscripts a, b, c, d, and m represent the degree of polymerization, with a and c taking values ​​of 0 or 1–10, b and d taking values ​​of 5–20, and m taking values ​​of 1–10; R and R 1 It is an alkyl group with 4 to 20 carbon atoms; or an aromatic hydrocarbon; The amount of the branched polyether used is 15-30% of the total mass of the foam control composition; C. Fatty alcohol polyether, wherein the structural formula of the fatty alcohol polyether is as follows: R 2 O(EO) e (PO) f H (II) R in equation (II) 2 It is an alkyl group with 6 to 30 carbon atoms. The subscripts e and f are the degree of polymerization of EO and PO, respectively. e is 0 or 1 to 20, and f is 1 to 30. The amount of the fatty alcohol polyether used is 5-15% of the total mass of the foam control composition; D. Silica, wherein the silica is fumed silica produced by hydrophobic methods, with a specific surface area of ​​150–400 m². 2 / g, the hydrophobicity M tested by the methanol method is 55-70%; the dosage is 3-8% of the total mass of the foam control composition; E. Hydroxyl compound, wherein the hydroxyl compound refers to a compound containing hydroxyl groups composed of carbon, hydrogen and oxygen elements, selected from ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol, glycerol, butanol, pentanol, hexanol, octanol, diethylene glycol monobutyl ether; the amount of the hydroxyl compound is 5-15% of the total mass of the foam control composition; F. Emulsifier, wherein the emulsifier is a nonionic surfactant, and the amount used is 3 to 10% of the total mass of the foam control composition; The preparation method of the foam control composition is as follows: Add the hydroxyl compound to the container, start stirring, and add silica in batches while controlling the speed at 500-6000 rpm. At this time, a transparent silica dispersion is obtained. At room temperature, add polyether ester polymer, branched polyether and fatty alcohol polyether to another container, turn on the stirrer and raise the temperature to 50-80°C, set the speed to 600-3000 rpm, slowly add silica dispersion, and after all silica dispersion has been added, increase the speed to 1000-5000 rpm and keep at 120-150°C for 0.5-3 hours. Then add emulsifier, stir evenly and cool to room temperature to obtain foam control composition.

2. The polyether-type foam control composition according to claim 1, characterized in that, The ratio of raw materials used in the synthesis of the polyether ester polymer and the synthesis method are as follows: Adipic acid: 1 mol; Trimethylolpropane: 0.9–1.1 mol; Polyether: 5–15 mol; Acidic catalyst: 0.4–1% of the total mass of adipic acid, trimethylolpropane, and polyether; The preparation method of the polyether ester polymer is as follows: Adipic acid, trimethylolpropane, and an acidic catalyst are added sequentially to a flask equipped with a thermometer, nitrogen protection, and a stirrer. The stirring is turned on, and the temperature is raised to 150–200°C for 1–3 hours. Then, polyether is added, and the reaction continues at 150–200°C for 2–6 hours until no water is generated. The mixture is then cooled to room temperature to obtain the polyether ester polymer.

3. The polyether-type foam control composition according to claim 1, characterized in that, The hydrophobic silica is obtained by heating and stirring hydrophilic silica and a hydrophobic agent in a reaction vessel; the hydrophobic agent is selected from low-viscosity trimethylsiloxy-terminated polydimethylsiloxane, low-viscosity hydroxyl-terminated polydimethylsiloxane, hexamethyldisilazane, hexamethyldisilazane, dimethyldiethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, trimethylchlorosilane, dimethyldichlorosilane, methyltrichlorosilane, tetrachlorosilane, stearic acid, tetradecyl alcohol, hexadecyl alcohol, octadecyl alcohol, stearyl alcohol, octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, and hexamethylcyclotrisiloxane.

4. The polyether-type foam control composition according to claim 3, characterized in that, The hydrophobic agent of the aforementioned hydrophobic silica is a fatty alcohol with 14 to 18 carbon atoms.

5. The polyether-type foam control composition according to claim 1, wherein the emulsifier is selected from nonylphenol polyoxyethylene ether, octylphenol polyoxyethylene ether, laurate polyoxyethylene ether, oleic acid polyoxyethylene ether, lauryl alcohol polyoxyethylene ether, octyl alcohol polyoxyethylene ether, isooctyl alcohol polyoxyethylene ether, isodecyl alcohol polyoxyethylene ether, isotridecyl alcohol polyoxyethylene ether, hexadecyl alcohol polyoxyethylene ether, octadecyl alcohol polyoxyethylene ether, oleyl alcohol polyoxyethylene ether, sorbitan monolaurate, sorbitan monopalmitate, and sorbitan monostearate. The following are one or more mixtures of sorbitan monooleate, sorbitan tristearate, sorbitan trioleate, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan monooleate, polyoxyethylene sorbitan monooleate, polyoxyethylene sorbitan tristearate, polyoxyethylene oleate polyoxyethylene ether, polyoxyethylene oleate polyoxyethylene polyoxypropylene ether, castor oil polyoxyethylene ether, and castor oil polyoxyethylene polyoxypropylene ether.

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