A quick defoaming powder defoaming agent and a preparation method thereof

Abstract

The application discloses a powder defoaming agent with quick defoaming and a preparation method thereof, and relates to the technical field of defoaming agents. The powder defoaming agent comprises the following raw materials in parts by weight: polyether modified silicone oil: 30-40 parts, organic silicon emulsion: 2-5 parts, dispersant: 3-6 parts, emulsifier: 4-6 parts, thickening agent: 1-2 parts, and porous carrier: 50-70 parts. The powder defoaming agent prepared by the application has good defoaming and bubble suppressing performance, dispersion performance and thermal stability.

Description

Technical Field

[0001] This invention relates to the field of defoamer technology, specifically to a fast-acting defoaming powder defoamer and its preparation method. Background Technology

[0002] In industrial production, foam generation can severely impact production efficiency, product quality, and equipment operational stability. Powder defoamers, as important industrial additives, are widely used in plastics processing, coatings production, wastewater treatment, detergent manufacturing, and many other fields. However, existing powder defoamer technology still faces many unresolved issues. Traditional powder defoamers often use calcium oxide and silicone oil as their main active ingredients. While they possess some defoaming ability, they have significant shortcomings in practical applications. First, insufficient defoaming speed is a major weakness of current technology, especially in dynamic foam systems. Conventional defoamers cannot quickly reduce foam height, leading to low production efficiency. Second, powder defoamers commonly exhibit particle agglomeration. When exposed to a humid environment, the particles absorb moisture and stick together, forming lumps. This not only reduces defoaming efficiency but also causes clogging of processing equipment filters or defects such as white spots on the final product surface.

[0003] Chinese invention patent CN111467843A discloses a powder defoamer and its preparation method. The components of the defoamer include: 45-55% polyether-type defoamer mother liquor, 28-38% organosilicon defoamer mother liquor, 7% quicklime, 9.8% water, and 0.2% flame retardant. The defoamer prepared by this invention has uniform fineness, stable performance, and excellent defoaming rate, but its dispersibility is poor. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the purpose of this invention is to provide a fast-acting defoaming powder defoamer and its preparation method.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A fast-acting defoaming powder defoamer, comprising the following raw materials in parts by weight:

[0007] Polyether-modified silicone oil: 30-40 parts, organosilicon emulsion: 2-5 parts, dispersant: 3-6 parts, emulsifier: 4-6 parts, thickener: 1-2 parts, porous carrier: 50-70 parts;

[0008] The dispersant is prepared by the following method:

[0009] S1: 2-Methacryloyloxyethylphosphocholine reacts with 1,2-bis(bromoacetoxy)ethane to produce intermediate 1;

[0010] S2: Intermediate 1 reacts with dimethylaminoethyl methacrylate to generate intermediate 2;

[0011] S3: Intermediate 2 reacts with 3-bromopropyltrimethoxysilane to generate a dispersant.

[0012] In step S1, the molar ratio of 2-methacryloyloxyethyl phosphocholine and 1,2-bis(bromoacetoxy)ethane is (20-24):1.

[0013] In step S2, the molar ratio of intermediate 1 to dimethylaminoethyl methacrylate is 1:(4-6).

[0014] In step S3, the molar ratio of intermediate 2 to 3-bromopropyltrimethoxysilane is 1:(4.1-6.1).

[0015] The emulsifier is prepared by the following method:

[0016] A1: Dodecylamine reacts with glycidol to form a long-chain alkyl tertiary amine compound;

[0017] A2: Long-chain alkyl tertiary amine compounds react with 1,8-dichloroperfluorooctane to generate fluorine-modified long-chain alkyl quaternary ammonium salt compounds;

[0018] A3: Fluorine-modified long-chain alkyl quaternary ammonium salts react with chlorosulfonic acid to form emulsifiers.

[0019] In step A1, the molar ratio of dodecylamine to glycidol is 1:2.1.

[0020] In step A2, the molar ratio of the long-chain alkyl tertiary amine compound to 1,8-dichloroperfluorooctane is 2.1:1.

[0021] In step A3, the molar ratio of the fluorine-modified long-chain alkyl quaternary ammonium salt compound to chlorosulfonic acid is 1:8.5.

[0022] The thickener is sodium alginate.

[0023] The porous carrier is composed of silica and diatomaceous earth.

[0024] The mass ratio of silica to diatomaceous earth is (1-3):1.

[0025] A method for preparing a fast-acting defoaming powder defoamer includes the following steps:

[0026] (1) Weigh the following by weight: polyether modified silicone oil: 30-40 parts, organosilicon emulsion: 2-5 parts, dispersant: 3-6 parts, emulsifier: 4-6 parts, thickener: 1-2 parts, porous carrier: 50-70 parts;

[0027] (2) The organosilicon emulsion, polyether modified silicone oil, thickener, dispersant and emulsifier are sheared and emulsified, then added to a porous carrier and stirred evenly. The mixture is then homogenized and dispersed under high pressure using a high-pressure homogenizer. After drying, crushing and sieving, the powder defoamer is obtained.

[0028] Due to the adoption of the above technical solutions, the beneficial effects of the present invention include:

[0029] (1) The dispersant prepared in this invention reduces surface tension by using quaternary ammonium salt groups and phosphate ester groups, destroys the foam film and stabilizes the interface, while siloxane crosslinking improves thermal stability, thereby significantly enhancing the foam suppression performance and durability of the defoamer.

[0030] (2) The emulsifier prepared in this invention significantly enhances the permeability and stability of the defoamer at the interface through the synergistic hydrophobic effect of dodecyl and perfluorooctyl groups and the strong hydrophilicity of sulfonic acid groups, thereby improving the defoaming speed and long-lasting foam suppression ability. Detailed Implementation

[0031] The following description, in conjunction with specific embodiments, provides further details, but the present invention is not limited to these embodiments.

[0032] Example 1: Preparation of dispersant:

[0033] S1: Under nitrogen protection, 250 ml of toluene, 0.2 mol of 2-methacryloyloxyethyl phosphocholine, 0.01 mol of 1,2-bis(bromoacetoxy)ethane, and 2.2 g of pentamethyldiethylenetriamine were added to the reactor and stirred until homogeneous. 1.8 g of cuprous bromide was added, and the mixture was heated to 70 °C. After reacting for 4 h, the mixture was cooled to room temperature and passed through a neutral alumina column to obtain a crude product to remove the copper catalyst. The crude product was dissolved in 400 ml of tetrahydrofuran and rotary evaporated at 60 °C for 30 min to form a concentrated solution. Under magnetic stirring, the concentrated solution was slowly added dropwise (2 mL / min) to 300 ml of cold acetone. The mixture was stirred, and a precipitate was formed. The precipitate was filtered and dried under vacuum at 70 °C for 6 h to obtain intermediate 1, with a number average molecular weight of 6200. The reaction equation is shown below.

[0034]

[0035] Its 1H NMR data are as follows:

[0036] 1 H NMR (400 MHz, Chloroform- d) δ 4.36 – 4.23 (m, 48H), 4.18 (t, J =3.1 Hz, 32H), 4.09 (t, J = 4.7 Hz, 32H), 3.63 (t, J = 3.1 Hz, 32H), 3.17 (s,180H), 2.61 – 2.13 (t, J = 8.2 Hz, 32H), 2.12 – 1.71 (t, J = 8.2 Hz, 32H), 1.20 (s, 60H).

[0037] S2: Under nitrogen protection, 400 ml of tetrahydrofuran, 0.01 mol of intermediate 1, and 0.04 mol of dimethylaminoethyl methacrylate were added to the reactor and stirred until homogeneous. Then, 2.5 g of pentamethyldiethylenetriamine and 2 g of cuprous bromide were added. After reflux for 3 hours, the mixture was cooled to room temperature and passed through a neutral alumina column to obtain a crude product to remove the copper catalyst. The crude product was dissolved in 400 ml of tetrahydrofuran and evaporated at 60 °C for 30 min to form a concentrated solution. Under magnetic stirring, the concentrated solution was slowly added dropwise (2 mL / min) to 300 ml of cold acetone. The mixture was stirred, and a precipitate was formed. After filtration, the precipitate was dried under vacuum at 70 °C for 6 hours to obtain intermediate 2, with a number-average molecular weight of 6830. The reaction equation is shown below:

[0038]

[0039] Its 1H NMR data are as follows:

[0040] 1 H NMR (400 MHz, Chloroform- d ) δ 4.43 – 4.24 (m, 48H), 4.18 (t, J =3.1 Hz, 32H), 4.13 – 4.02 (m, 32H), 3.63 (t, J = 3.1 Hz, 32H), 3.17 (s,180H), 2.97 – 2.75 (m, 16H), 2.57 – 2.15 (m, 56H), 2.12 – 1.74 (m, 50H), 1.32 – 1.11 (m, 60H).

[0041] S3: Under nitrogen protection, 400 ml of isopropanol and 0.01 mol of intermediate 2 were added to the reactor and stirred at room temperature for 5 min. Then, 0.041 mol of 3-bromopropyltrimethoxysilane was added and stirred until homogeneous. The mixture was heated to 70 °C and reacted for 10 h. After cooling to room temperature, the mixture was distilled under reduced pressure at 60 °C for 2 h. Then, a mixed solvent of ethyl acetate / anhydrous ethanol (V(ethyl acetate):V(anhydrous ethanol) = 20:1) was added for recrystallization three times (300 ml each time). The mixture was dried under vacuum at 70 °C for 4 h to obtain the dispersant, which had a number average molecular weight of 7480. The reaction equation is shown below:

[0042]

[0043] Its 1H NMR data are as follows:

[0044] 1 H NMR (400 MHz, Chloroform- d ) δ 4.57 – 4.41 (m, 4H), 4.37 – 4.20 (m, 48H), 4.18 (t, J = 3.1 Hz, 32H), 4.12 – 4.02 (m, 32H), 3.91 – 3.76 (m, 36H), 3.71 – 3.53 (m, 32H), 3.46 (t, J = 9.7 Hz, 8H), 3.17 (s, 180H), 2.56 – 2.34 (m, 4H), 2.33 – 2.13 (m, 72H), 2.02 – 1.70 (m, 50H), 1.31 – 1.14 (m, 60H),0.97 (t, J = 9.9 Hz, 8H).

[0045] Example 2: Preparation of dispersant:

[0046] S1: Under nitrogen protection, 250 ml of toluene, 0.22 mol of 2-methacryloyloxyethyl phosphocholine, 0.01 mol of 1,2-bis(bromoacetoxy)ethane, and 2.2 g of pentamethyldiethylenetriamine were added to the reactor and stirred until homogeneous. 1.8 g of cuprous bromide was added, and the temperature was raised to 75 °C. After reacting for 3.5 h, the mixture was cooled to room temperature and passed through a neutral alumina column to obtain a crude product to remove the copper catalyst. The crude product was dissolved in 400 ml of tetrahydrofuran and rotary evaporated at 60 °C for 30 min to form a concentrated solution. Under magnetic stirring, the concentrated solution was slowly added dropwise (2 mL / min) to 300 ml of cold acetone, stirred, and a precipitate was formed. The precipitate was filtered and dried under vacuum at 70 °C for 6 h to obtain intermediate 1 with a number average molecular weight of 6790.

[0047] S2: Under nitrogen protection, 400 ml of tetrahydrofuran, 0.01 mol of intermediate 1, and 0.06 mol of dimethylaminoethyl methacrylate were added to the reactor and stirred until homogeneous. Then, 2.5 g of pentamethyldiethylenetriamine and 2 g of cuprous bromide were added. After reflux for 3 h, the mixture was cooled to room temperature and passed through a neutral alumina column to obtain a crude product to remove the copper catalyst. The crude product was dissolved in 400 ml of tetrahydrofuran and evaporated at 60 °C for 30 min to form a concentrated solution. Under magnetic stirring, the concentrated solution was slowly added dropwise (2 mL / min) to 300 ml of cold acetone. The mixture was stirred, and a precipitate was formed. The precipitate was filtered and dried under vacuum at 70 °C for 6 h to obtain intermediate 2 with a number average molecular weight of 7740.

[0048] S3: Under nitrogen protection, 400 ml of isopropanol and 0.01 mol of intermediate 2 were added to the reactor and stirred at room temperature for 5 min. Then, 0.061 mol of 3-bromopropyltrimethoxysilane was added and stirred until well mixed. The mixture was heated to 75 °C and reacted for 9 h. After cooling to room temperature, the mixture was distilled under reduced pressure at 60 °C for 2 h. Then, a mixed solvent of ethyl acetate / anhydrous ethanol (V(ethyl acetate):V(anhydrous ethanol) = 20:1) was added and recrystallized 3 times (300 ml each time). The mixture was dried under vacuum at 70 °C for 4 h to obtain the dispersant with a number average molecular weight of 8720.

[0049] Example 3: Preparation of dispersant:

[0050] S1: Under nitrogen protection, 250 ml of toluene, 0.24 mol of 2-methacryloyloxyethyl phosphocholine, 0.01 mol of 1,2-bis(bromoacetoxy)ethane, and 2.2 g of pentamethyldiethylenetriamine were added to the reactor and stirred until homogeneous. 1.8 g of cuprous bromide was added, and the temperature was raised to 80 °C. After reacting for 3 h, the mixture was cooled to room temperature and passed through a neutral alumina column to obtain a crude product to remove the copper catalyst. The crude product was dissolved in 400 ml of tetrahydrofuran and evaporated at 60 °C for 30 min to form a concentrated solution. Under magnetic stirring, the concentrated solution was slowly added dropwise (2 mL / min) to 300 ml of cold acetone, stirred, and a precipitate was formed. The precipitate was filtered and dried under vacuum at 70 °C for 6 h to obtain intermediate 1 with a number average molecular weight of 7380.

[0051] S2: Under nitrogen protection, 400 ml of tetrahydrofuran, 0.01 mol of intermediate 1, and 0.06 mol of dimethylaminoethyl methacrylate were added to the reactor and stirred until homogeneous. Then, 2.5 g of pentamethyldiethylenetriamine and 2 g of cuprous bromide were added. After reflux for 2 h, the mixture was cooled to room temperature and passed through a neutral alumina column to obtain a crude product to remove the copper catalyst. The crude product was dissolved in 400 ml of tetrahydrofuran and evaporated at 60 °C for 30 min to form a concentrated solution. Under magnetic stirring, the concentrated solution was slowly added dropwise (2 mL / min) to 300 ml of cold acetone. The mixture was stirred, and a precipitate was formed. The precipitate was filtered and dried under vacuum at 70 °C for 6 h to obtain intermediate 2 with a number average molecular weight of 8320.

[0052] S3: Under nitrogen protection, 400 ml of isopropanol and 0.01 mol of intermediate 2 were added to the reactor and stirred at room temperature for 5 min. Then, 0.061 mol of 3-bromopropyltrimethoxysilane was added and stirred until well mixed. The mixture was heated to 80 °C and reacted for 8 h. After cooling to room temperature, the mixture was distilled under reduced pressure at 60 °C for 2 h. Then, a mixed solvent of ethyl acetate / anhydrous ethanol (V(ethyl acetate):V(anhydrous ethanol) = 20:1) was added and recrystallized 3 times (300 ml each time). The mixture was dried under vacuum at 70 °C for 4 h to obtain the dispersant with a number average molecular weight of 9300.

[0053] Example 4: Preparation of emulsifier:

[0054] A1: Add 200 ml of anhydrous ethanol and 0.1 mol of dodecylamine to the reactor, heat to 35 °C and stir for 20 min, then slowly add 0.21 mol of glycidol dropwise over 20 min, stir to mix, heat to 40 °C and react for 6 h, then distill under reduced pressure at 45 °C for 3 h to obtain a long-chain alkyl tertiary amine compound; the reaction equation is shown below:

[0055]

[0056] Its 1H NMR data are as follows:

[0057] 1 H NMR (500 MHz, Chloroform- d ) δ 3.80 – 3.74 (m, 2H), 3.72 – 3.62 (m,6H), 3.48 (ddd, J = 11.5, 6.0, 5.4 Hz, 2H), 2.85 (dd, J = 11.9, 5.6 Hz, 2H), 2.68 – 2.49 (m, 4H), 1.57 – 1.19 (m, 20H), 0.95 – 0.78 (m, 3H).

[0058] A2: Under nitrogen protection, 400 mL of a mixed solvent of isopropanol and toluene (isopropanol:toluene (V:V) = 8:2), 0.21 mol of a long-chain alkyl tertiary amine compound were added to the reactor. The mixture was stirred at room temperature for 5 min, then 0.1 mol of 1,8-dichloroperfluorooctane and 0.15 mol of K₂CO₃ were added and stirred until homogeneous. The mixture was heated to 80 °C and reacted for 12 h. After cooling to room temperature, 200 mL of ethyl acetate was added, and the mixture was stirred for 30 min. The mixture was then filtered under reduced pressure, distilled under reduced pressure at 50 °C for 2 h, and dried under vacuum at 70 °C for 4 h to obtain a fluorine-modified long-chain alkyl quaternary ammonium salt compound. The reaction equation is shown below:

[0059]

[0060] Its 1H NMR data are as follows:

[0061] 1 H NMR (500 MHz, Chloroform- d ) δ 6.46 (d, J = 6.7 Hz, 4H), 4.29 (tdt,J = 9.2, 6.6, 5.8 Hz, 4H), 4.13 (t, J = 5.1 Hz, 4H), 4.04 – 3.94 (m, 4H), 3.94 – 3.67 (m, 12H), 3.54 (ddd, J = 11.6, 5.8, 5.2 Hz, 4H), 1.92 – 1.70 (m,4H), 1.55 – 1.38 (m, 4H), 1.38 – 1.15 (m, 32H), 1.02 – 0.74 (m, 6H).

[0062] A3: Under nitrogen protection, 200 ml of dichloromethane and 0.1 mol of fluorine-modified long-chain alkyl quaternary ammonium salt compound were added to the reactor and stirred until homogeneous. Under ice bath conditions, a dichloromethane solution of chlorosulfonic acid (0.85 mol of chlorosulfonic acid dissolved in 200 ml of dichloromethane) was slowly added dropwise over 20 min. After reacting at room temperature for 4 h, a saturated aqueous solution of NaHCO3 was slowly added to adjust the pH to 9. The mixture was then rotary evaporated at 35 °C for 2 h. The crude product after rotary evaporation was transferred to a round-bottom flask, 500 ml of anhydrous ethanol was added, and the mixture was refluxed for 30 min. The inorganic salts were removed by filtration, and the product was recrystallized three times with 300 ml of acetone to obtain the emulsifier. The reaction equation is shown below:

[0063]

[0064] Its 1H NMR data are as follows:

[0065] 1H NMR (500 MHz, Chloroform- d ) δ 5.10 (tt, J = 9.7, 7.3 Hz, 4H), 4.46 (dd, J = 11.6, 7.3 Hz, 4H), 4.34 – 4.18 (m, 8H), 4.01 (ddt, J = 13.6, 9.7,3.2 Hz, 4H), 3.85 (tdt, J = 10.4, 7.2, 3.3 Hz, 4H), 1.83 – 1.71 (m, 4H), 1.50 – 1.39 (m, 4H), 1.38 – 1.21 (m, 32H), 0.93 – 0.83 (m, 6H).

[0066] Example 5: Preparation of powder defoamer:

[0067] (1) Weigh: polyether modified silicone oil: 300g, organosilicon emulsion: 20g, dispersant (prepared in Example 1): 30g, emulsifier (prepared in Example 4): 40g, thickener (sodium alginate): 10g, porous carrier (250g silica + 250g diatomaceous earth): 500g;

[0068] (2) The organosilicon emulsion, polyether modified silicone oil, thickener, dispersant and emulsifier are sheared and emulsified at 80°C, with a rotation speed of 3000 rpm for 30 min. Then, a porous carrier is added and the mixture is stirred for 1 h. After stirring evenly, the mixture is homogenized and dispersed under high pressure using a high-pressure homogenizer at a pressure of 20 MPa for 30 min. The mixture is dried at 80°C for 2 h, and then pulverized and sieved to obtain the powder defoamer.

[0069] Example 6: Preparation of powder defoamer:

[0070] (1) Weigh: polyether modified silicone oil: 350g, organosilicon emulsion: 30g, dispersant (prepared in Example 2): 45g, emulsifier (prepared in Example 4): 50g, thickener (sodium alginate): 15g, porous carrier (400g silica + 200g diatomaceous earth): 600g;

[0071] (2) The organosilicon emulsion, polyether modified silicone oil, thickener, dispersant and emulsifier are sheared and emulsified at 80°C, with a rotation speed of 3000 rpm for 30 min. Then, a porous carrier is added and the mixture is stirred for 1 h. After stirring evenly, the mixture is homogenized and dispersed under high pressure using a high-pressure homogenizer at a pressure of 20 MPa for 30 min. The mixture is dried at 80°C for 2 h, and then pulverized and sieved to obtain the powder defoamer.

[0072] Example 7 Preparation of powder defoamer:

[0073] (1) Weigh: polyether modified silicone oil: 400g, organosilicon emulsion: 50g, dispersant (prepared in Example 3): 60g, emulsifier (prepared in Example 4): 60g, thickener (sodium alginate): 20g, porous carrier (525g silica + 175g diatomaceous earth): 700g;

[0074] (2) The organosilicon emulsion, polyether modified silicone oil, thickener, dispersant and emulsifier are sheared and emulsified at 80°C, with a rotation speed of 3000 rpm for 30 min. Then, a porous carrier is added and the mixture is stirred for 1 h. After stirring evenly, the mixture is homogenized and dispersed under high pressure using a high-pressure homogenizer at a pressure of 20 MPa for 30 min. The mixture is dried at 80°C for 2 h, and then pulverized and sieved to obtain the powder defoamer.

[0075] Comparative Example 1

[0076] The preparation method of the powder defoamer is basically the same as that in Example 6, except that the dispersant is replaced with an equal weight of the dispersant prepared by the following method:

[0077] The preparation method of the dispersant is basically the same as that in Example 2, except that 2-methacryloyloxyethyl phosphocholine in step S1 is replaced with an equimolar amount of acryloyloxyethyl trimethylammonium chloride.

[0078] Comparative Example 2

[0079] The preparation method of the powder defoamer is basically the same as that in Example 6, except that the dispersant is replaced with an equal weight of the dispersant prepared by the following method:

[0080] The preparation method of the dispersant is basically the same as that in Example 2, except that 2-methacryloyloxyethyl phosphocholine in step S1 is replaced with an equimolar amount of dodecyl methacrylate.

[0081] Comparative Example 3

[0082] The preparation method of the powder defoamer is basically the same as that in Example 6, except that the dispersant is replaced with an equal weight of the dispersant prepared by the following method:

[0083] The preparation method of the dispersant is basically the same as that in Example 2, except that the amount of 2-methacryloyloxyethyl phosphocholine added in step S1 is 0.1 mol.

[0084] Comparative Example 4

[0085] The preparation method of the powder defoamer is basically the same as that in Example 6, except that the dispersant is replaced with an equal weight of the dispersant prepared by the following method:

[0086] The preparation method of the dispersant is basically the same as that in Example 2, except that the amount of 2-methacryloyloxyethyl phosphocholine added in step S1 is 0.4 mol.

[0087] Comparative Example 5

[0088] The preparation method of the dispersant is basically the same as that in Example 2, except that in step S3, 3-bromopropyltrimethoxysilane is replaced with an equimolar amount of 2-bromo-2-methylpropionic acid (3-trimethoxysilyl)propyl ester.

[0089] Comparative Example 6

[0090] The preparation method of the powder defoamer is basically the same as that in Example 6, except that the emulsifier is replaced with an equal weight of emulsifier prepared by the following method:

[0091] The preparation method of the emulsifier is basically the same as that in Example 4, except that the dodecylamine in step A1 is replaced with an equimolar amount of n-hexylamine.

[0092] Comparative Example 7

[0093] The preparation method of the powder defoamer is basically the same as that in Example 6, except that the emulsifier is replaced with an equal weight of emulsifier prepared by the following method:

[0094] The preparation method of the emulsifier is basically the same as that in Example 4, except that the 1,8-dichloroperfluorooctane in step A2 is replaced with an equimolar amount of 1,3-dichlorohexafluoropropane.

[0095] Comparative Example 8

[0096] The preparation method of the powder defoamer is basically the same as that in Example 6, except that the emulsifier is replaced with an equal weight of emulsifier prepared by the following method:

[0097] The preparation method of the emulsifier is basically the same as that in Example 4, except that the 1,8-dichloroperfluorooctane in step A2 is replaced with an equimolar amount of 1,6-dichloroperfluorohexane.

[0098] The polyether-modified silicone oil used in the embodiments and comparative examples of this application is Dow Corning OFX-0400; the silicone emulsion is SILRES® BS 1306; the silica is fumed silica, model HL-150, produced by Hubei Huifu Nanomaterials Co., Ltd.; and the molecular weight of sodium alginate is Mw=2.85×10⁻⁶. 5The diatomaceous earth contains 91.4 wt% SiO2 and has a D50 of 15 μm. It is produced by Baishan Xingtai Diatomaceous Earth New Material Co., Ltd.

[0099] Dispersibility test: 10g of the powdered defoamer prepared in the examples and comparative examples were added to beakers, followed by 50g of distilled water. The mixtures were stirred for 30 minutes, and their dispersibility was observed. The dispersibility index of the defoamer in water was divided into four levels: excellent, good, medium, and poor, as shown below:

[0100] Advantages: No oil spots on the solution surface;

[0101] Good: The solution is milky white in color and contains a small number of fine white oil droplets;

[0102] In the middle: the solution is milky white, with many white oil phase droplets, and the droplets are relatively large;

[0103] Poor: The defoamer cannot be dispersed in water.

[0104] Defoaming test: 100 mL of a 0.2% sodium dodecylbenzenesulfonate aqueous solution was added to a 1 L graduated cylinder as the foaming liquid. The solution was heated to 70°C in a water bath, and N2 was bubbled through at a gas rate of 2 L / min. When the foam volume reached 500 mL, 1 g of the powdered defoamer prepared in the examples and comparative examples was added, and timing was started simultaneously. The time taken for all the foam to disappear was recorded; the shorter the time, the better the defoaming effect. After defoaming, bubbling continued, and the time taken for the foam height to reach 500 mL again was recorded; the longer the time, the better the foam suppression effect of the defoamer.

[0105] Thermal stability test: Weigh 1.0g of powdered defoamer, add 100mL of deionized water, stir magnetically for 10min to disperse it evenly, dispense 20mL into a pressure-resistant reactor, place the sample into an autoclave, set 121℃ and 0.1MPa, maintain for 30min, and remove after natural cooling to room temperature; check whether the solution separates into layers; the test results are shown in Table 1.

[0106] Table 1 Performance Indicators of Powder Defoamer

[0107]

[0108] The phosphorocholine units in the dispersant prepared in this invention form a hydrophilic layer through strong hydration, reducing surface tension. Quaternary ammonium salt groups can be directionally adsorbed onto the surface of hydrophobic defoaming particles, preventing aggregation through electrostatic stabilization. The synergistic effect of phosphorocholine and quaternary ammonium salt groups stabilizes the newly formed interface, achieving dynamic foam suppression. Methoxysilane can undergo hydrolytic condensation to form a Si-O-Si covalent network with the matrix, enhancing interfacial bonding and improving the thermal stability of the dispersant, allowing the defoamer to maintain long-term stability at high temperatures. The synergistic effect of phosphorocholine, quaternary ammonium salt groups, and methoxysilane enables it to rapidly migrate to the gas-liquid interface in the powder defoamer system, disrupting foam and improving defoaming ability.

[0109] The long-chain perfluoroalkyl group introduced into the emulsifier prepared in this invention imparts extremely low surface tension, significantly enhancing its spreading ability at the gas-liquid interface, thereby improving defoaming efficiency; the alkyl chain portion provides good oil solubility, which is beneficial for the effective dispersion and stabilization of active components in non-polar systems, preventing foam regeneration and enhancing foam suppression performance; in addition, the introduced sulfonic acid group further enhances hydrophilicity and charge stability, giving the emulsifier good water solubility and pH adaptability, which is beneficial for maintaining stability in different media and responding quickly to the foam formation process.

[0110] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. However, any modifications, alterations, and variations made by those skilled in the art without departing from the scope of the present invention based on the disclosed technical content are equivalent embodiments of the present invention. Furthermore, any modifications, alterations, and variations made to the above embodiments based on the essential technology of the present invention are still within the protection scope of the present invention.

Claims

1. A fast-acting defoaming powder defoamer, characterized in that, The ingredients include the following parts by weight: Polyether-modified silicone oil: 30-40 parts, organosilicon emulsion: 2-5 parts, dispersant: 3-6 parts, emulsifier: 4-6 parts, thickener: 1-2 parts, porous carrier: 50-70 parts; The dispersant is prepared by the following method: S1: 2-Methacryloyloxyethylphosphocholine reacts with 1,2-bis(bromoacetoxy)ethane to produce intermediate 1; S2: Intermediate 1 reacts with dimethylaminoethyl methacrylate to generate intermediate 2; S3: Intermediate 2 reacts with 3-bromopropyltrimethoxysilane to generate a dispersant.

2. The powder defoamer for rapid defoaming according to claim 1, characterized in that, In step S1, the molar ratio of 2-methacryloyloxyethyl phosphocholine and 1,2-bis(bromoacetoxy)ethane is (20-24):

1.

3. The powder defoamer for rapid defoaming according to claim 1, characterized in that, In step S2, the molar ratio of intermediate 1 to dimethylaminoethyl methacrylate is 1:(4-6).

4. The powder defoamer for rapid defoaming according to claim 1, characterized in that, In step S3, the molar ratio of intermediate 2 to 3-bromopropyltrimethoxysilane is 1:(4.1-6.1).

5. The powder defoamer for rapid defoaming according to claim 1, characterized in that, The emulsifier is prepared by the following method: A1: Dodecylamine reacts with glycidol to form a long-chain alkyl tertiary amine compound; A2: Long-chain alkyl tertiary amine compounds react with 1,8-dichloroperfluorooctane to generate fluorine-modified long-chain alkyl quaternary ammonium salt compounds; A3: Fluorine-modified long-chain alkyl quaternary ammonium salts react with chlorosulfonic acid to form emulsifiers.

6. The powder defoamer for rapid defoaming according to claim 5, characterized in that, In step A1, the molar ratio of dodecylamine to glycidol is 1:2.

1.

7. The powder defoamer for rapid defoaming according to claim 5, characterized in that, In step A2, the molar ratio of the long-chain alkyl tertiary amine compound to 1,8-dichloroperfluorooctane is 2.1:

1.

8. The powder defoamer for rapid defoaming according to claim 5, characterized in that, In step A3, the molar ratio of the fluorine-modified long-chain alkyl quaternary ammonium salt compound to chlorosulfonic acid is 1:8.

5.

9. The powder defoamer for rapid defoaming according to claim 1, characterized in that, The thickener is sodium alginate.

10. The powder defoamer for rapid defoaming according to claim 1, characterized in that, The porous carrier is composed of silica and diatomaceous earth.

11. The powder defoamer for rapid defoaming according to claim 10, characterized in that, The mass ratio of silica to diatomaceous earth is (1-3):

1.

12. A method for preparing a rapid defoaming powder defoamer according to any one of claims 1-11, characterized in that, Includes the following steps: (1) Weigh the following by weight: polyether modified silicone oil: 30-40 parts, organosilicon emulsion: 2-5 parts, dispersant: 3-6 parts, emulsifier: 4-6 parts, thickener: 1-2 parts, porous carrier: 50-70 parts; (2) The organosilicon emulsion, polyether modified silicone oil, thickener, dispersant and emulsifier are sheared and emulsified, then added to a porous carrier and stirred evenly. The mixture is then homogenized and dispersed under high pressure using a high-pressure homogenizer. After drying, crushing and sieving, the powder defoamer is obtained.

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