Fluorosilicon powder defoaming agent and preparation method thereof

Abstract

This invention relates to the field of powder defoamer technology, specifically to a fluorosilicone powder defoamer and its preparation method. This fluorosilicone powder defoamer is prepared by blending an organosilicon defoamer, a fluoropolymer, and a solid carrier. The introduction of a specially synthesized fluoropolymer, due to the extremely low surface tension of the fluorine atoms in the fluoropolymer, effectively reduces the surface tension of the system and synergistically enhances the defoaming ability with the organosilicon defoamer. This improves the sustained foam suppression effect of the defoamer, resulting in good stability, convenient storage and transportation, and long-lasting foam suppression performance. This fluorosilicone powder defoamer can be applied in industries with many surfactant systems, such as cement mortar, detergents, daily chemicals, industrial cleaning, and water treatment, and has a broad potential market value due to its long-lasting foam suppression performance.

Description

Technical Field

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

[0002] Foam is a common phenomenon in industrial processes such as washing, daily chemicals, industrial cleaning, and water treatment. The presence of foam often causes significant harm to industrial production, such as greatly limiting production capacity, wasting raw materials and products, prolonging reaction cycles, affecting product quality, hindering accurate measurement, polluting the environment, and causing accidents. Therefore, eliminating harmful foam is crucial. In some product systems that use a large amount of surfactants, conventional silicone defoamers are often used. While they have good defoaming effects, their foam-suppressing effects are poor, and the defoaming performance of some silicone defoamers gradually declines.

[0003] Most defoamers used in practical applications are emulsion-type. Emulsion-type products generally suffer from poor dispersibility, poor stability, and difficulties in transportation and storage. They are prone to stratification when stored for extended periods, and after dilution, they must be used within a short period; otherwise, their defoaming performance will significantly decrease, causing considerable inconvenience in practical use. This is especially true when these defoamers are used in industries with a high concentration of surfactants, such as cement mortar, detergents, daily chemicals, industrial cleaning, and water treatment, where the defoaming performance and stability often fail to meet application requirements. Summary of the Invention

[0004] To overcome the shortcomings and deficiencies of existing technologies, one of the objectives of this invention is to provide a fluorosilicone powder defoamer with properties such as acid resistance, alkali resistance, and high temperature resistance. It exhibits rapid defoaming speed, good stability, and is convenient and safe to use, while also overcoming the drawbacks of conventional emulsion-type defoamers, such as poor stability and difficulties in transportation and storage. This fluorosilicone powder defoamer can be applied in industries with numerous surfactant systems, such as cement mortar, washing, daily chemicals, industrial cleaning, and water treatment, and possesses long-lasting defoaming and foam-suppressing properties.

[0005] The second objective of this invention is to provide a method for preparing a fluorosilicone powder defoamer. This method is simple to operate, easy to control, has high production efficiency, low production cost, and can be used for large-scale production.

[0006] One of the objectives of this invention is achieved through the following technical solution: a fluorosilicone powder defoamer, comprising the following raw materials in parts by weight:

[0007] 5-25 parts of silicone defoamer

[0008] 5-20 parts of fluoropolymer

[0009] 60-90 parts of solid carrier.

[0010] Preferably, the preparation method of each part of the organosilicon defoamer includes the following steps:

[0011] (R1) Take 20-30 parts by weight of silicone paste, 2-10 parts of the first emulsifier, 0.1-1 parts of the first thickener and 60-80 parts of water, and set aside.

[0012] (R2) Add the silicone paste and the first emulsifier to the reactor and mix them evenly while heating;

[0013] (R3) After heating the water, add a portion of hot water dropwise to the reaction vessel in step (R2). After the system undergoes a phase reversal, add the remaining hot water dropwise. After the addition is complete, continue the reaction for 40-80 minutes.

[0014] (R4) Add the first thickener to the reaction vessel of step (R3) and stir for 40-80 minutes to obtain the organosilicon defoamer.

[0015] Preferably, the first emulsifier is at least one of glyceryl monostearate, Span series emulsifiers, Tween series emulsifiers, polyoxyethylene stearyl ether, fatty alcohol polyoxyethylene ether emulsifiers, alkylphenol and ethylene oxide condensate emulsifiers, fatty alcohol and ethylene oxide condensate emulsifiers, or EL series emulsifiers; the first thickener is at least one of carboxymethyl cellulose, propylene glycol alginate, methyl cellulose, sodium starch phosphate, sodium carboxymethyl cellulose, sodium alginate, casein, sodium polyacrylate, polyoxyethylene, and polyvinylpyrrolidone.

[0016] Preferably, each part of the fluoropolymer comprises the following parts by weight of raw materials:

[0017]

[0018]

[0019] Preferably, the fluorinated monomer is at least one selected from hexafluoroisopropyl methacrylate, perfluorohexylethyl methacrylate, perfluorohexylethyl methacrylate, perfluorobutylethyl methacrylate, perfluorobutylethyl methacrylate, 2,2,2-trifluoroethyl methacrylate, dodecafluoroheptyl methacrylate, or hexafluorobutyl methacrylate.

[0020] Preferably, the second emulsifier is at least one of glyceryl monostearate, Span series emulsifiers, Tween series emulsifiers, polyoxyethylene stearyl ether, fatty alcohol polyoxyethylene ether emulsifiers, alkylphenol and ethylene oxide condensate emulsifiers, fatty alcohol and ethylene oxide condensate emulsifiers, or EL series emulsifiers; the second thickener is at least one of carboxymethyl cellulose, propylene glycol alginate, methyl cellulose, sodium starch phosphate, sodium carboxymethyl cellulose, sodium alginate, casein, sodium polyacrylate, polyoxyethylene, and polyvinylpyrrolidone.

[0021] Preferably, the initiator is at least one selected from 2,2'-azobis(2-methylpropionitrile), 2,2'-azobisisobutyronitrile, benzoyl peroxide, di-tert-butyl peroxide, ammonium persulfate, potassium persulfate, and 2,2'-azobisisobutyranin dihydrochloride.

[0022] Preferably, the preparation method of each portion of the fluoropolymer includes the following steps:

[0023] (D1) Take the fluorinated monomer, initiator, second emulsifier, second thickener, MQ silicone resin, fumed silica and water by weight, and set aside;

[0024] (D2) Add the fluorinated monomer, the second emulsifier, MQ silicone resin, fumed silica and water to a high-speed disperser, and heat to 50-70℃ for pre-emulsification to obtain a pre-emulsion.

[0025] (D3) Add the pre-emulsion to the reactor, then add the initiator, heat to 70-90℃, and react at a constant temperature for 6-10 hours;

[0026] (D4) Add the second thickener to the reactor of step (D3) and stir for 40-80 minutes to obtain the fluoropolymer.

[0027] Preferably, the solid carrier is at least one of sodium sulfate, sodium carbonate, sodium metasilicate, talc, diatomaceous earth, phosphate, starch, bentonite, attapulgite, 4A zeolite, calcium carbonate, industrial salt, or sodium tripolyphosphate.

[0028] The second objective of this invention is achieved through the following technical solution: the preparation method of the above-mentioned fluorosilicone powder defoamer includes the following steps: taking organosilicon defoamer, fluoropolymer and solid carrier in parts by weight, mixing them evenly, granulating them by granulator, and then drying them by dryer to obtain fluorosilicone powder defoamer.

[0029] The beneficial effects of this invention are as follows: This invention provides a fluorosilicone powder defoamer, prepared by blending an organosilicon defoamer, a fluoropolymer, and a solid carrier. This method utilizes a powder carrier to adsorb the organosilicon defoamer and the fluoropolymer to prepare a powder-like defoamer, exhibiting good defoaming effect, good stability, convenient storage and transportation, and long-lasting foam suppression performance. This fluorosilicone powder defoamer can be applied in industries with many surfactant systems, such as cement mortar, washing, daily chemicals, industrial cleaning, and water treatment, and possesses long-lasting foam suppression performance, indicating broad potential market value.

[0030] The preparation method of the present invention is simple to operate, easy to control, has high production efficiency, low production cost, and can be used for large-scale production. Detailed Implementation

[0031] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to embodiments. The content mentioned in the embodiments is not intended to limit the present invention.

[0032] A fluorosilicone powder defoamer, comprising the following raw materials in parts by weight:

[0033] 5-25 parts of silicone defoamer

[0034] 5-20 parts of fluoropolymer

[0035] 60-90 parts of solid carrier.

[0036] The unique feature of this invention lies in the introduction of a specially synthesized fluoropolymer. Due to the extremely low surface tension of the fluorine atoms in the fluoropolymer, the surface tension of the system is effectively reduced, and it synergistically enhances the defoaming ability of the silicone defoamer, thus improving the sustained foam-suppressing effect. Furthermore, the low surface tension of the CF bond and the presence of strong CO and CC covalent bonds in the fluoropolymer result in high chemical inertness, extremely high antioxidant properties, strong corrosion resistance, high decomposition temperature, thermal stability, oxidative stability, and good chemical inertness and insulating properties. It is non-toxic, harmless to humans, and environmentally friendly. In addition, since fluoropolymers and silicone defoamers are generally not easily miscible, if the two are directly mixed, the storage stability will be poor, and they are prone to separation or demulsification, which will adversely affect the defoaming performance of the defoamer. Moreover, although silicone defoamers have lower surface tension and higher chemical stability, they are not as low as the surface tension of fluoropolymers. Blending fluoropolymers and silicone defoamers with a solid carrier produces a powder defoamer that is beneficial for both dispersion and storage stability, ensuring its long-lasting defoaming and foam-suppressing performance.

[0037] Furthermore, the preparation method of each portion of the said silicone defoamer includes the following steps:

[0038] (R1) Take 20-30 parts by weight of silicone paste, 2-10 parts of the first emulsifier, 0.1-1 parts of the first thickener and 60-80 parts of water, and set aside.

[0039] (R2) Add the silicone paste and the first emulsifier to the reactor and mix them evenly while heating;

[0040] (R3) After heating the water, add a portion of hot water dropwise to the reaction vessel in step (R2). After the system undergoes a phase reversal, add the remaining hot water dropwise. After the addition is complete, continue the reaction for 40-80 minutes.

[0041] (R4) Add the first thickener to the reaction vessel of step (R3) and stir for 40-80 minutes to obtain the organosilicon defoamer.

[0042] Furthermore, the silicone paste is selected from Wacker Chemie 352 silicone paste from Germany, which has good defoaming effect and can still exert good defoaming effect under high temperature, high pressure and strong acid and alkali environments. It has high stability and low surface tension, which allows it to penetrate into narrow spaces, making the foam easier to break. Preparing an organosilicon defoamer with it, along with a first emulsifier, a first thickener and water, is more conducive to subsequent mixing with fluoropolymers and easier diffusion and distribution into the foaming system with the help of a solid carrier, thus improving the defoaming effect and stability.

[0043] Furthermore, the first emulsifier is at least one of glyceryl monostearate, Span series emulsifiers, Tween series emulsifiers, polyoxyethylene stearyl ether, fatty alcohol polyoxyethylene ether emulsifiers, alkylphenol and ethylene oxide condensate emulsifiers, fatty alcohol and ethylene oxide condensate emulsifiers, or EL series emulsifiers; the first thickener is at least one of carboxymethyl cellulose, propylene glycol alginate, methyl cellulose, sodium starch phosphate, sodium carboxymethyl cellulose, sodium alginate, casein, sodium polyacrylate, polyoxyethylene, and polyvinylpyrrolidone.

[0044] Furthermore, each portion of the fluoropolymer comprises the following parts by weight of raw materials:

[0045]

[0046] Using the above technical solution, the fluoropolymer, with fluorinated monomers as the main component, incorporates hydrophobic particles such as silica and MQ silicone resin. This allows for effective mixing with the silicone defoamer and promotes easier distribution and diffusion of the silicone defoamer into the foaming system. The fluorinated monomers undergo polymerization via an initiator to obtain the fluoropolymer, which is then wrapped around the surfaces of MQ silicone resin and silica. The fluoropolymer possesses numerous fluorine atoms and extremely low surface tension trifluoromethyl groups, which, together with the siloxane groups in the silicone defoamer, contribute to the defoaming effect. Furthermore, because the fluoropolymer and silicone defoamer are mixed with a solid carrier, they are more easily diffused and distributed into the foaming system. The Si-O bonds in the silicone defoamer particles and the Si-O silicon-oxygen bonds in the hydrophobic particles of MQ silicone resin in fluoropolymer particles have similar functional groups, making them more effective at mixing. In actual use, the synergistic effect of the silicone defoamer particles and the fluoropolymer particles, along with the presence of silica and MQ silicone resin, causes the defoamer particles to move onto the bubble film. Then, due to the extremely low surface tension of the fluorine atoms in the silicone defoamer and fluoropolymer, a large surface tension difference is formed between them and the bubble film, reducing the cohesion of the bubble film and causing the foam to lose stability and rupture rapidly.

[0047] Furthermore, the fluorinated monomer is at least one selected from hexafluoroisopropyl methacrylate, perfluorohexylethyl methacrylate, perfluorohexylethyl methacrylate, perfluorobutylethyl methacrylate, perfluorobutylethyl methacrylate, 2,2,2-trifluoroethyl methacrylate, dodecafluoroheptyl methacrylate, or hexafluorobutyl methacrylate.

[0048] Using the above technical solution, the fluoropolymer not only has a large number of fluorine atoms and extremely low surface tension groups such as trifluoromethyl groups, but also has high chemical stability. The fluoropolymer and the organosilicon defoamer work together to play a stabilizing role, and have higher stability in acidic or alkaline environments, thus providing continuous defoaming and foam suppression effects.

[0049] Furthermore, the second emulsifier is at least one of glyceryl monostearate, Span series emulsifiers, Tween series emulsifiers, polyoxyethylene stearyl alcohol ether, fatty alcohol polyoxyethylene ether emulsifiers, alkylphenol and ethylene oxide condensate emulsifiers, fatty alcohol and ethylene oxide condensate emulsifiers, or EL series emulsifiers; the second thickener is at least one of carboxymethyl cellulose, propylene glycol alginate, methyl cellulose, sodium starch phosphate, sodium carboxymethyl cellulose, sodium alginate, casein, sodium polyacrylate, polyoxyethylene, and polyvinylpyrrolidone.

[0050] Furthermore, the initiator is at least one selected from 2,2'-azobis(2-methylpropionitrile), 2,2'-azobisisobutyronitrile, benzoyl peroxide, di-tert-butyl peroxide, ammonium persulfate, potassium persulfate, and 2,2'-azobisisobutyranin dihydrochloride.

[0051] Furthermore, the preparation method of each portion of the fluoropolymer includes the following steps:

[0052] (D1) Take the fluorinated monomer, initiator, second emulsifier, second thickener, MQ silicone resin, fumed silica and water by weight, and set aside;

[0053] (D2) Add the fluorinated monomer, the second emulsifier, MQ silicone resin, fumed silica and water to a high-speed disperser, and heat to 50-70℃ for pre-emulsification to obtain a pre-emulsion.

[0054] (D3) Add the pre-emulsion to the reactor, then add the initiator, heat to 70-90℃, and react at a constant temperature for 6-10 hours;

[0055] (D4) Add the second thickener to the reactor of step (D3) and stir for 40-80 minutes to obtain the fluoropolymer.

[0056] Among them, MQ silicone resin is a very unique type of polysiloxane, an organosilicon resin composed of monofunctional Si-O units (M units) and tetrafunctional Si-O units (SiQZ, abbreviated as Q units), exhibiting a tightly packed spherical bilayer structure. Here, MQ silicone resin, as hydrophobic particles, does not participate in the chemical reaction of fluoropolymers, but when mixed with fluoropolymers, the fluoropolymers entangle and encapsulate the MQ silicone resin. As hydrophobic particles, MQ silicone resin readily binds to the siloxane molecules in the organosilicon defoamer, facilitating the binding of fluoropolymers and organosilicon defoamer molecules, and promoting the diffusion of fluoropolymers to the foam surface, thus promoting foam breakage. The added silica component, being hydrophobic silica particles, further enhances the mixing of fluoropolymers and organosilicon defoamers, and facilitates their diffusion and distribution to the foam surface, further promoting foam breakage. Meanwhile, the role of hydrophobic silica is to pull the surfactants originally adsorbed on the surface of the liquid film down into the aqueous phase of the liquid film, thereby reducing the surfactant concentration on the surface of the liquid film and thus increasing the overall instability of the foam. For example, it reduces the surface viscosity of the liquid film, leading to a decrease in the self-healing effect of the liquid film and accelerating the drainage rate of the liquid film. Due to the decrease in surface viscosity, the permeability of the liquid film increases, the gas diffusion rate increases, and the life of the foam is greatly shortened, leading to the destruction of the foam.

[0057] Furthermore, the solid carrier is at least one of sodium sulfate, sodium carbonate, sodium metasilicate, talc, diatomaceous earth, phosphate, starch, bentonite, attapulgite, 4A zeolite, calcium carbonate, industrial salt, or sodium tripolyphosphate. By mixing the fluoropolymer and the organosilicon defoamer with the solid carrier, a powder defoamer is prepared, which is beneficial to the dispersion of both and to improving storage stability, thus ensuring its long-lasting defoaming and foam-suppressing performance.

[0058] The preparation method of the above-mentioned fluorosilicone powder defoamer includes the following steps: taking organosilicon defoamer, fluoropolymer and solid carrier in parts by weight, mixing them evenly, granulating them by granulator, and then drying them by dryer to obtain fluorosilicone powder defoamer.

[0059] This preparation method is simple to operate, easy to control, has high production efficiency, and low production cost, making it suitable for large-scale production.

[0060] Example 1

[0061] A fluorosilicone powder defoamer, comprising the following raw materials in parts by weight:

[0062] 10 parts of silicone defoamer

[0063] 10 parts of fluoropolymer

[0064] 80 copies of solid carrier.

[0065] The preparation method of each portion of the aforementioned silicone defoamer includes the following steps:

[0066] (R1) Take 20 parts by weight of silicone paste, 8 parts of the first emulsifier, 0.5 parts of the first thickener and 80 parts of water, and set aside.

[0067] (R2) Add the silicone paste and the first emulsifier to the reactor and mix them evenly while heating;

[0068] (R3) After heating the water, add 90% by weight of the hot water to the reaction vessel in step (R2). After the system reverses, add the remaining hot water. Continue the reaction for 60 minutes after the addition is complete.

[0069] (R4) Add the first thickener to the reaction vessel of step (R3) and stir for 60 minutes to obtain the organosilicon defoamer.

[0070] The silicone paste is selected from Wacker 352 silicone paste from Germany.

[0071] The first emulsifier is a mixture of Span-80 and Tween-80 in a weight ratio of 1:1; the first thickener is carboxymethyl cellulose.

[0072] Each portion of the fluoropolymer comprises the following parts by weight of raw materials:

[0073]

[0074] The fluorinated monomer is a mixture of perfluorohexyl ethyl methacrylate and hexafluorobutyl methacrylate in a weight ratio of 1:1.

[0075] The second emulsifier is a mixture of Span-80 and Tween-80 in a weight ratio of 1:1; the second thickener is carboxymethyl cellulose.

[0076] The initiator is 2,2'-azobisisobutyronitrile.

[0077] The preparation method of each of the fluoropolymers includes the following steps:

[0078] (D1) Take the fluorinated monomer, initiator, second emulsifier, second thickener, MQ silicone resin, fumed silica and water by weight, and set aside;

[0079] (D2) Add the fluorinated monomer, the second emulsifier, MQ silicone resin, fumed silica and water to a high-speed disperser, heat to 50°C and pre-emulsify for 10 min to obtain a pre-emulsion;

[0080] (D3) Add the pre-emulsion to the reactor, then add the initiator, heat to 75°C, and react at a constant temperature for 6 hours;

[0081] (D4) Add the second thickener to the reactor of step (D3) and stir for 40 minutes to obtain the fluoropolymer.

[0082] The solid carrier is sodium sulfate.

[0083] The preparation method of the above-mentioned fluorosilicone powder defoamer includes the following steps: taking organosilicon defoamer, fluoropolymer and solid carrier in parts by weight, mixing them evenly, granulating them by granulator, and then drying them by dryer to obtain fluorosilicone powder defoamer.

[0084] Example 2

[0085] A fluorosilicone powder defoamer, comprising the following raw materials in parts by weight:

[0086] 10 parts of silicone defoamer

[0087] 10 parts of fluoropolymer

[0088] 80 copies of solid carrier.

[0089] The preparation method of each portion of the aforementioned silicone defoamer includes the following steps:

[0090] (R1) Take 20 parts by weight of silicone paste, 10 parts of the first emulsifier, 0.5 parts of the first thickener and 80 parts of water, and set aside.

[0091] (R2) Add the silicone paste and the first emulsifier to the reactor and mix them evenly while heating;

[0092] (R3) After heating the water, add 90% by weight of the hot water to the reaction vessel in step (R2). After the system reverses, add the remaining hot water. Continue the reaction for 60 minutes after the addition is complete.

[0093] (R4) Add the first thickener to the reaction vessel of step (R3) and stir for 60 minutes to obtain the organosilicon defoamer.

[0094] The silicone paste is selected from Wacker 352 silicone paste from Germany.

[0095] The first emulsifier is a mixture of OP-10 and EL-40 in a weight ratio of 1:1; the first thickener is carboxymethyl cellulose.

[0096] Each portion of the fluoropolymer comprises the following parts by weight of raw materials:

[0097]

[0098] The fluorinated monomer is a mixture of perfluorobutyl ethyl acrylate and hexafluorobutyl methacrylate in a weight ratio of 1:1.

[0099] The second emulsifier is a mixture of OP-10 and EL-40 in a weight ratio of 1:1; the second thickener is carboxymethyl cellulose.

[0100] The initiator is 2,2'-azobisisobutyronitrile.

[0101] The preparation method of each of the fluoropolymers includes the following steps:

[0102] (D1) Take the fluorinated monomer, initiator, second emulsifier, second thickener, MQ silicone resin, fumed silica and water by weight, and set aside;

[0103] (D2) Add the fluorinated monomer, the second emulsifier, MQ silicone resin, fumed silica and water to a high-speed disperser, heat to 50°C and pre-emulsify for 10 min to obtain a pre-emulsion;

[0104] (D3) Add the pre-emulsion to the reactor, then add the initiator, heat to 75°C, and react at a constant temperature for 6 hours;

[0105] (D4) Add the second thickener to the reactor of step (D3) and stir for 40 minutes to obtain the fluoropolymer.

[0106] The solid carrier is sodium carbonate.

[0107] The preparation method of the above-mentioned fluorosilicone powder defoamer includes the following steps: taking organosilicon defoamer, fluoropolymer and solid carrier in parts by weight, mixing them evenly, granulating them by granulator, and then drying them by dryer to obtain fluorosilicone powder defoamer.

[0108] Example 3

[0109] A fluorosilicone powder defoamer, comprising the following raw materials in parts by weight:

[0110] 10 parts of silicone defoamer

[0111] 10 parts of fluoropolymer

[0112] 80 copies of solid carrier.

[0113] The preparation method of each portion of the aforementioned silicone defoamer includes the following steps:

[0114] (R1) Take 20 parts by weight of silicone paste, 10 parts of the first emulsifier, 0.5 parts of the first thickener and 80 parts of water, and set aside.

[0115] (R2) Add the silicone paste and the first emulsifier to the reactor and mix them evenly while heating;

[0116] (R3) After heating the water, add 90% by weight of the hot water to the reaction vessel in step (R2). After the system reverses, add the remaining hot water. Continue the reaction for 60 minutes after the addition is complete.

[0117] (R4) Add the first thickener to the reaction vessel of step (R3) and stir for 60 minutes to obtain the organosilicon defoamer.

[0118] The silicone paste is selected from Wacker 352 silicone paste from Germany.

[0119] The first emulsifier is a mixture of Span-80 and Tween-80 in a weight ratio of 1:1; the first thickener is carboxymethyl cellulose.

[0120] Each portion of the fluoropolymer comprises the following parts by weight of raw materials:

[0121]

[0122]

[0123] The fluorinated monomer is a mixture of hexafluoroisopropyl methacrylate and hexafluorobutyl methacrylate in a weight ratio of 1:1.

[0124] The second emulsifier is a mixture of OP-10, EL-40 and Tween-80 in a weight ratio of 1:1:1; the second thickener is carboxymethyl cellulose.

[0125] The initiator is 2,2'-azobisisobutyronitrile.

[0126] The preparation method of each of the fluoropolymers includes the following steps:

[0127] (D1) Take the fluorinated monomer, initiator, second emulsifier, second thickener, MQ silicone resin, fumed silica and water by weight, and set aside;

[0128] (D2) Add the fluorinated monomer, the second emulsifier, MQ silicone resin, fumed silica and water to a high-speed disperser, heat to 50°C and pre-emulsify for 10 min to obtain a pre-emulsion;

[0129] (D3) Add the pre-emulsion to the reactor, then add the initiator, heat to 75°C, and react at a constant temperature for 6 hours;

[0130] (D4) Add the second thickener to the reactor of step (D3) and stir for 40 minutes to obtain the fluoropolymer.

[0131] The solid carrier is sodium tripolyphosphate.

[0132] The preparation method of the above-mentioned fluorosilicone powder defoamer includes the following steps: taking organosilicon defoamer, fluoropolymer and solid carrier in parts by weight, mixing them evenly, granulating them by granulator, and then drying them by dryer to obtain fluorosilicone powder defoamer.

[0133] Example 4

[0134] A fluorosilicone powder defoamer, comprising the following raw materials in parts by weight:

[0135] 10 parts of silicone defoamer

[0136] 10 parts of fluoropolymer

[0137] 80 copies of solid carrier.

[0138] The preparation method of each portion of the aforementioned silicone defoamer includes the following steps:

[0139] (R1) Take 20 parts by weight of silicone paste, 8 parts of the first emulsifier, 0.5 parts of the first thickener and 80 parts of water, and set aside.

[0140] (R2) Add the silicone paste and the first emulsifier to the reactor and mix them evenly while heating;

[0141] (R3) After heating the water, add 90% by weight of the hot water to the reaction vessel in step (R2). After the system reverses, add the remaining hot water. Continue the reaction for 60 minutes after the addition is complete.

[0142] (R4) Add the first thickener to the reaction vessel of step (R3) and stir for 60 minutes to obtain the organosilicon defoamer.

[0143] The silicone paste is selected from Wacker 352 silicone paste from Germany.

[0144] The first emulsifier is a mixture of Span-80 and Tween-80 in a weight ratio of 1:1; the first thickener is carboxymethyl cellulose.

[0145] Each portion of the fluoropolymer comprises the following parts by weight of raw materials:

[0146]

[0147] The fluorinated monomer is perfluorohexylethyl methacrylate.

[0148] The second emulsifier is a mixture of Span-80 and Tween-80 in a weight ratio of 1:1; the second thickener is carboxymethyl cellulose.

[0149] The initiator is 2,2'-azobisisobutyronitrile.

[0150] The preparation method of each of the fluoropolymers includes the following steps:

[0151] (D1) Take the fluorinated monomer, initiator, second emulsifier, second thickener, MQ silicone resin, fumed silica and water by weight, and set aside;

[0152] (D2) Add the fluorinated monomer, the second emulsifier, MQ silicone resin, fumed silica and water to a high-speed disperser, heat to 50°C and pre-emulsify for 10 min to obtain a pre-emulsion;

[0153] (D3) Add the pre-emulsion to the reactor, then add the initiator, heat to 75°C, and react at a constant temperature for 6 hours;

[0154] (D4) Add the second thickener to the reactor of step (D3) and stir for 40 minutes to obtain the fluoropolymer.

[0155] The solid carrier is sodium sulfate.

[0156] The preparation method of the above-mentioned fluorosilicone powder defoamer includes the following steps: taking organosilicon defoamer, fluoropolymer and solid carrier in parts by weight, mixing them evenly, granulating them by granulator, and then drying them by dryer to obtain fluorosilicone powder defoamer.

[0157] Comparative Example 1

[0158] The difference between this comparative example and Example 1 is as follows:

[0159] A fluorosilicone powder defoamer, comprising the following raw materials in parts by weight:

[0160] 10 parts of silicone defoamer

[0161] 90 copies of solid carrier.

[0162] The preparation method of each portion of the aforementioned silicone defoamer includes the following steps:

[0163] (R1) Take 20 parts by weight of silicone paste, 8 parts of the first emulsifier, 0.5 parts of the first thickener and 80 parts of water, and set aside.

[0164] (R2) Add the silicone paste and the first emulsifier to the reactor and mix them evenly while heating;

[0165] (R3) After heating the water, add 90% by weight of the hot water to the reaction vessel in step (R2). After the system reverses, add the remaining hot water. Continue the reaction for 60 minutes after the addition is complete.

[0166] (R4) Add the first thickener to the reaction vessel of step (R3) and stir for 60 minutes to obtain the organosilicon defoamer.

[0167] The silicone paste is selected from Wacker 352 silicone paste from Germany.

[0168] The first emulsifier is a mixture of Span-80 and Tween-80 in a weight ratio of 1:1; the first thickener is carboxymethyl cellulose.

[0169] The solid carrier is sodium sulfate.

[0170] The preparation method of the above-mentioned fluorosilicone powder defoamer includes the following steps: after mixing the organosilicon defoamer and solid carrier evenly according to the weight parts, granulating them by a granulator, and then drying them by a dryer to obtain the fluorosilicone powder defoamer.

[0171] Comparative Example 2

[0172] The difference between this comparative example and Example 2 is as follows:

[0173] A fluorosilicone powder defoamer, comprising the following raw materials in parts by weight:

[0174] 10 parts of fluoropolymer

[0175] 80 copies of solid carrier.

[0176] Each portion of the fluoropolymer comprises the following parts by weight of raw materials:

[0177]

[0178] The fluorinated monomer is a mixture of perfluorobutyl ethyl acrylate and hexafluorobutyl methacrylate in a weight ratio of 1:1.

[0179] The second emulsifier is a mixture of OP-10 and EL-40 in a weight ratio of 1:1; the second thickener is carboxymethyl cellulose.

[0180] The initiator is 2,2'-azobisisobutyronitrile.

[0181] The preparation method of each of the fluoropolymers includes the following steps:

[0182] (D1) Take the fluorinated monomer, initiator, second emulsifier, second thickener, MQ silicone resin, fumed silica and water by weight, and set aside;

[0183] (D2) Add the fluorinated monomer, the second emulsifier, MQ silicone resin, fumed silica and water to a high-speed disperser, heat to 50°C and pre-emulsify for 10 min to obtain a pre-emulsion;

[0184] (D3) Add the pre-emulsion to the reactor, then add the initiator, heat to 75°C, and react at a constant temperature for 6 hours;

[0185] (D4) Add the second thickener to the reactor of step (D3) and stir for 40 minutes to obtain the fluoropolymer.

[0186] The solid carrier is sodium carbonate.

[0187] The preparation method of the above-mentioned fluorosilicone powder defoamer includes the following steps: taking organosilicon defoamer, fluoropolymer and solid carrier in parts by weight, mixing them evenly, granulating them by granulator, and then drying them by dryer to obtain fluorosilicone powder defoamer.

[0188] Comparative Example 3

[0189] The difference between this comparative example and Example 3 is as follows:

[0190] A fluorosilicone powder defoamer, comprising the following raw materials in parts by weight:

[0191] 10 parts of silicone defoamer

[0192] 10 parts of acrylic polymer

[0193] 80 copies of solid carrier.

[0194] The preparation method of each portion of the aforementioned silicone defoamer includes the following steps:

[0195] (R1) Take 20 parts by weight of silicone paste, 10 parts of the first emulsifier, 0.5 parts of the first thickener and 80 parts of water, and set aside.

[0196] (R2) Add the silicone paste and the first emulsifier to the reactor and mix them evenly while heating;

[0197] (R3) After heating the water, add 90% by weight of the hot water to the reaction vessel in step (R2). After the system reverses, add the remaining hot water. Continue the reaction for 60 minutes after the addition is complete.

[0198] (R4) Add the first thickener to the reaction vessel of step (R3) and stir for 60 minutes to obtain the organosilicon defoamer.

[0199] The silicone paste is selected from Wacker 352 silicone paste from Germany.

[0200] The first emulsifier is a mixture of Span-80 and Tween-80 in a weight ratio of 1:1; the first thickener is carboxymethyl cellulose.

[0201] The preparation method of each portion of the acrylic polymer includes the following steps:

[0202] (D1) Take 20 parts by weight of acrylate monomer, 0.5 parts of initiator, 9 parts of second emulsifier, 0.5 parts of second thickener, 4 parts of MQ silicone resin, 4 parts of fumed silica and 66 parts of water, and set aside.

[0203] (D2) Add acrylate monomers, second emulsifier, MQ silicone resin, fumed silica and water to a high-speed disperser, heat to 50°C and pre-emulsify for 10 min to obtain a pre-emulsion;

[0204] (D3) Add the pre-emulsion to the reactor, then add the initiator, heat to 75°C, and react at a constant temperature for 6 hours;

[0205] (D4) Add the second thickener to the reactor of step (D3) and stir for 40 minutes to obtain the acrylic polymer.

[0206] The acrylate monomers are a mixture of dodecyl methacrylate and methyl methacrylate in a weight ratio of 1:1.

[0207] The second emulsifier is a mixture of OP-10, EL-40 and Tween-80 in a weight ratio of 1:1:1; the second thickener is carboxymethyl cellulose.

[0208] The initiator is 2,2'-azobisisobutyronitrile.

[0209] The solid carrier is sodium tripolyphosphate.

[0210] The preparation method of the above-mentioned fluorosilicone powder defoamer includes the following steps: taking organosilicon defoamer, acrylic polymer and solid carrier in parts by weight, mixing them evenly, granulating them by granulator, and then drying them by dryer to obtain fluorosilicone powder defoamer.

[0211] Comparative Example 4

[0212] The difference between this comparative example and Example 1 is as follows:

[0213] A fluorosilicone powder defoamer, comprising the following raw materials in parts by weight:

[0214] 10 parts of silicone defoamer

[0215] 10 parts of fluoropolymer

[0216] 80 copies of solid carrier.

[0217] The preparation method of each portion of the aforementioned silicone defoamer includes the following steps:

[0218] (R1) Take 20 parts by weight of silicone paste, 8 parts of the first emulsifier, 0.5 parts of the first thickener and 80 parts of water, and set aside.

[0219] (R2) Add the silicone paste and the first emulsifier to the reactor and mix them evenly while heating;

[0220] (R3) After heating the water, add 90% by weight of the hot water to the reaction vessel in step (R2). After the system reverses, add the remaining hot water. Continue the reaction for 60 minutes after the addition is complete.

[0221] (R4) Add the first thickener to the reaction vessel of step (R3) and stir for 60 minutes to obtain the organosilicon defoamer.

[0222] The silicone paste is selected from Wacker 352 silicone paste from Germany.

[0223] The first emulsifier is a mixture of Span-80 and Tween-80 in a weight ratio of 1:1; the first thickener is carboxymethyl cellulose.

[0224] Each portion of the fluoropolymer comprises the following parts by weight of raw materials:

[0225]

[0226] The fluorinated monomer is a mixture of perfluorohexyl ethyl methacrylate and hexafluorobutyl methacrylate in a weight ratio of 1:1.

[0227] The second emulsifier is a mixture of Span-80 and Tween-80 in a weight ratio of 1:1; the second thickener is carboxymethyl cellulose.

[0228] The initiator is 2,2'-azobisisobutyronitrile.

[0229] The preparation method of each of the fluoropolymers includes the following steps:

[0230] (D1) Take the fluorinated monomer, initiator, second emulsifier, second thickener, MQ silicone resin and water by weight, and set aside;

[0231] (D2) Add the fluorinated monomer, the second emulsifier, MQ silicone resin and water to a high-speed disperser, heat to 50°C and pre-emulsify for 10 min to obtain a pre-emulsion;

[0232] (D3) Add the pre-emulsion to the reactor, then add the initiator, heat to 75°C, and react at a constant temperature for 6 hours;

[0233] (D4) Add the second thickener to the reactor of step (D3) and stir for 40 minutes to obtain the fluoropolymer.

[0234] The solid carrier is sodium sulfate.

[0235] The preparation method of the above-mentioned fluorosilicone powder defoamer includes the following steps: taking organosilicon defoamer, fluoropolymer and solid carrier in parts by weight, mixing them evenly, granulating them by granulator, and then drying them by dryer to obtain fluorosilicone powder defoamer.

[0236] Comparative Example 5

[0237] The difference between this comparative example and Example 1 is as follows:

[0238] An organosilicon defoamer is prepared by mixing and diluting commercially available defoamer AT-990 with water at a weight ratio of 1:10.

[0239] Performance testing

[0240] The defoamers from Examples 1-4 were designated as Experimental Groups 1-4, respectively.

[0241] Take the defoamers from Examples 1-4, let them stand for 1 day, and record them as experimental groups 5-8 respectively;

[0242] Take the defoamers from comparative examples 1-5 and label them as control groups 1-5 respectively;

[0243] Take the defoamers from Comparative Examples 1-5, let them stand for 1 day, and record them as Comparative Examples 6-10 respectively.

[0244] The defoaming performance of experimental groups 1-8 and control groups 1-10 under the same conditions was tested using acid-base surfactant systems. The test methods are as follows:

[0245] Measure 100g of either an alkaline surfactant aqueous solution or an acidic surfactant aqueous solution, and 0.1g of defoamer into 250mL graduated plastic bottles. Place each bottle in an 80℃ constant temperature water bath for 10 minutes. Then place the bottles on a vertical shaker with the following parameters set: rotation speed: 450rpm, amplitude: 30mm. Shake for different durations, and record the defoaming time after each shake. After each shake, keep the bottles in the 80℃ constant temperature water bath for 5 minutes. If the defoamer can completely eliminate the foam on the liquid surface, record the time it takes for the foam to completely disappear. If it cannot completely eliminate the foam on the liquid surface, record the time it takes for the foam to reach the liquid surface. After the same shaking time, the shorter the defoaming time, the better the defoaming performance.

[0246] The alkaline surfactant aqueous solution is composed of the following components in weight percentage: 0.5% sodium dialkylbenzene sulfonate, 0.5% nonylphenol polyoxyethylene (10) ether, 1% sodium hydroxide and the balance deionized water;

[0247] The aqueous solution of the acidic surfactant is composed of the following components in weight percentage: 0.5% sodium dodecylbenzenesulfonate, 0.5% nonylphenol polyoxyethylene (10) ether, 1% sulfuric acid (concentration of 30 wt%) and the balance deionized water.

[0248] The test results are shown in Table 1 below:

[0249] Table 1

[0250]

[0251]

[0252] As shown in Table 1 above, the defoaming time of the powder defoamer in control group 1 was longer than that of experimental group 1, which only contained silicone defoamer emulsion and no fluoropolymers. This indicates that the addition of fluoropolymers is beneficial to improving the defoaming and foam suppression effects.

[0253] The defoaming time of the powder defoamer in control group 2 was longer than that of experimental group 2, which indicates that the effect of using fluoropolymer alone to prepare powder defoamer is not as good as the effect of fluoropolymer combined with organosilicon defoamer.

[0254] The powder defoamer in control group 3 used an acrylic polymer. The powder defoamer prepared by combining the acrylic polymer with a silicone defoamer did not have the same defoaming effect as the powder defoamer prepared by combining a fluoropolymer with a silicone defoamer. This indicates that powder defoamers prepared by combining other polymers with silicone defoamers do not improve the effect.

[0255] The fluoropolymer used in the powder defoamer of control group 4 did not contain MQ resin, and the defoaming time was longer than that of control group 1, indicating that the synergistic effect of silica and MQ resin is beneficial to improving the defoaming and foam suppression effect.

[0256] The silicone-based diluted emulsion defoamer in control group 5 had a longer defoaming time than that in experimental group 1 when used in a short period of time. Moreover, the defoaming time of control group 10 was even longer after standing for 1 day, indicating lower stability. In contrast, the defoaming time of experimental group 5 was not much different from that of experimental group 1, which shows that the powder defoamer of the present invention has better stability.

[0257] In summary, the experimental results show that the powder defoamer prepared by combining fluoropolymers with organosilicon defoamers has excellent defoaming and foam-suppressing effects and stability, and also exhibits excellent acid and alkali resistance.

[0258] The above embodiments are preferred implementations of the present invention. In addition, the present invention can be implemented in other ways. Any obvious substitutions without departing from the concept of the present invention are within the protection scope of the present invention.

Claims

1. A fluorosilicon powder antifoam agent, characterized by, The ingredients include the following parts by weight: 5-25 parts of silicone defoamer 5-20 parts of fluoropolymer 60-90 parts of solid carrier; Each portion of the fluoropolymer comprises the following parts by weight of raw materials: 20-60 parts of fluorinated monomer Initiator 0.1-1 part Second emulsifier 1-10 parts Second thickener 0.1-1 part 2-10 parts of MQ silicone resin 2-10 parts of silica 30-70 parts water; The fluorinated monomer is at least one of hexafluoroisopropyl methacrylate, perfluorohexylethyl methacrylate, perfluorohexylethyl methacrylate, perfluorobutylethyl methacrylate, perfluorobutylethyl methacrylate, 2,2,2-trifluoroethyl methacrylate, dodecafluoroheptyl methacrylate, or hexafluorobutyl methacrylate. The preparation method of each of the fluoropolymers includes the following steps: (D1) Take the fluorinated monomer, initiator, second emulsifier, second thickener, MQ silicone resin, fumed silica and water by weight, and set aside; (D2) Add the fluorinated monomer, the second emulsifier, MQ silicone resin, fumed silica and water to a high-speed disperser, and heat to 50-70℃ for pre-emulsification to obtain a pre-emulsion; (D3) Add the pre-emulsion to the reactor, then add the initiator, heat to 70-90℃, and react at a constant temperature for 6-10 hours; (D4) Add the second thickener to the reactor of step (D3) and stir for 40-80 minutes to obtain the fluoropolymer.

2. The fluorosilicone powder antifoam agent of claim 1, wherein: The preparation method of each portion of the aforementioned silicone defoamer includes the following steps: (R1) Take 20-30 parts by weight of silicone paste, 2-10 parts of the first emulsifier, 0.1-1 parts of the first thickener and 60-80 parts of water, and set aside. (R2) Add the silicone paste and the first emulsifier to the reactor and mix them evenly while heating; (R3) After heating the water, add a portion of hot water dropwise to the reaction vessel in step (R2). After the system undergoes a phase reversal, add the remaining hot water dropwise. After the addition is complete, continue the reaction for 40-80 minutes. (R4) Add the first thickener to the reactor of step (R3) and stir for 40-80 minutes to obtain the organosilicon defoamer.

3. The fluorosilicone powder antifoam agent of claim 2, wherein: The first emulsifier is at least one of glyceryl monostearate, Span series emulsifiers, Tween series emulsifiers, polyoxyethylene stearyl ether, fatty alcohol polyoxyethylene ether emulsifiers, alkylphenol and ethylene oxide condensate emulsifiers, fatty alcohol and ethylene oxide condensate emulsifiers, or EL series emulsifiers; the first thickener is at least one of carboxymethyl cellulose, propylene glycol alginate, methyl cellulose, sodium starch phosphate, sodium carboxymethyl cellulose, sodium alginate, casein, sodium polyacrylate, polyoxyethylene, and polyvinylpyrrolidone.

4. The fluorosilicone powder antifoam agent of claim 1, wherein: The second emulsifier is at least one of glyceryl monostearate, Span series emulsifiers, Tween series emulsifiers, polyoxyethylene stearyl alcohol ether, fatty alcohol polyoxyethylene ether emulsifiers, alkylphenol and ethylene oxide condensate emulsifiers, fatty alcohol and ethylene oxide condensate emulsifiers, or EL series emulsifiers; the second thickener is at least one of carboxymethyl cellulose, propylene glycol alginate, methyl cellulose, sodium starch phosphate, sodium carboxymethyl cellulose, sodium alginate, casein, sodium polyacrylate, polyoxyethylene, and polyvinylpyrrolidone.

5. The fluorosilicone powder defoamer according to claim 1, characterized in that: The initiator is at least one of 2,2'-azobis(2-methylpropionitrile), 2,2'-azobisisobutyronitrile, benzoyl peroxide, di-tert-butyl peroxide, ammonium persulfate, potassium persulfate, and 2,2'-azobisisobutyranin dihydrochloride.

6. The fluorosilicone powder defoamer according to claim 1, characterized in that: The solid carrier is at least one of sodium sulfate, sodium carbonate, sodium metasilicate, talc, diatomaceous earth, phosphate, starch, bentonite, attapulgite, 4A zeolite, calcium carbonate, industrial salt, or sodium tripolyphosphate.

7. A method for preparing a fluorosilicone powder defoamer as described in any one of claims 1-6, characterized in that, The process includes the following steps: taking parts by weight of organosilicon defoamer, fluoropolymer and solid carrier, mixing them evenly, granulating them through a granulator, and then drying them through a dryer to obtain fluorosilicone powder defoamer.

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