Preparation method of stable fatty alcohol emulsion

Abstract

The silane coupling agent is used for carrying out surface modification on silicon dioxide, finally obtained modified silicon dioxide can be adsorbed on an interface of a defoaming active matter and water, the effect of dispersing the active matter is achieved, the problem of product creaming caused by aggregation is avoided, and meanwhile the defoaming and foam inhibiting performance of the product can be improved; meanwhile, in the emulsification process, the nonionic surfactant and the acrylate polymer have a synergistic effect to emulsify active matters, so that the stability of the emulsion is further improved.

Description

Technical Field

[0001] The invention relates to a method for preparing a fatty alcohol emulsion, and therefore the invention belongs to the technical field of fine chemicals. Background Art

[0002] In the wet end of papermaking, sizing agents, retention and filtration aids, reinforcing agents, deinking agents, dry strength agents and other surface-active additives are used depending on the type of paper. Bubbles are easily generated during the circulation of white water in papermaking. The presence of these bubbles has a great impact on the paper, resulting in poor sizing, spots, light-transmitting points and small holes on the paper surface, and even paper breaks. It is also easy to reduce the operating efficiency of the pump and increase energy consumption.

[0003] The application of fatty alcohol emulsion defoamer in the wet end of papermaking is a mature technology. In the process of many years of research, technicians in this field have introduced paraffin, oil, white carbon black and other substances as defoaming active substances in addition to using fatty alcohols to continuously improve the defoaming and defoaming performance of the products. However, at the same time, due to the large variety of active substances, the requirements for emulsifiers and emulsification processes in the emulsification process are different, and it is difficult to balance each other, which leads to the instability of the emulsion, which is easy to cause problems such as emulsion creaming or stratification. The researchers' research on the stability of the emulsion is as follows: In CN101780383A, emulsifier and defoaming active substance (high carbon alcohol, glycerol polyether, acetylene alcohol) are dissolved in a dispersion medium, heated for pre-emulsification, and then homogenized for a long time to prepare a stable emulsion. The preparation of the emulsion is time-consuming and costly. In CN103628353A, a high-speed disperser is used to strongly disperse the fatty alcohol emulsion, and a polymer substance is introduced to prepare a stable emulsion. The preparation method is relatively complicated. US5807502 uses a C6-18 linear alkyl 1,2-diol and ethylene oxide adduct as an emulsifier to stabilize the fatty alcohol emulsion. Such emulsifiers are difficult to buy on the market, and the synthetic raw materials are expensive. CN1781574A uses C2-4 The addition product of alkylene oxide and primary alcohol with branched alkyl is used to stabilize fatty alcohol emulsion, but such method cannot solve the stability problem of natural fatty alcohol emulsion; CN107137959A prepares fatty alcohol, paraffin and grease into emulsion using nonionic surfactant, thickener and water respectively, and then mixes the three emulsions with anionic surfactant at room temperature to prepare stable emulsion, and the preparation process is relatively complicated; CN113577836A introduces different types of emulsifiers, and different types of emulsifiers are added in batches under different temperature conditions during the preparation process for emulsification, avoiding the problem of too much emulsified material during the emulsification process, resulting in poor product stability, and at the same time, introducing higher fatty alcohol fatty acid esters to improve the anti-foaming performance, further improve the stability of the product. The preparation temperature needs to be constantly paid attention to during the preparation process, and the preparation method is complicated. In order to improve the anti-foaming performance, other substances need to be introduced, which brings hidden dangers to the guarantee of product stability.

[0004] In summary, the above patents mainly improve the stability of fatty alcohol emulsions through relatively complex processes. At the same time, in order to take into account the anti-foaming performance, other substances need to be added, which brings new problems to ensure stability. Summary of the invention

[0005] The present invention uses a silane coupling agent to modify the surface of silicon dioxide. The modified silicon dioxide finally obtained can be adsorbed on the interface of the defoaming active substance and water to disperse the active substance, avoid the problem of product creaming caused by aggregation, and improve the defoaming and defoaming performance of the product. At the same time, in the emulsification process, a non-ionic surfactant and an acrylate polymer work together to emulsify the active substance, further improving the stability of the emulsion. Technical Solution

[0006] The stable fatty alcohol emulsion prepared by the present invention consists of the following components: A. Fatty alcohol The fatty alcohol is a monohydric to trihydric alcohol of C12-C30, selected from one or a mixture of synthetic fatty alcohols and natural fatty alcohols. Synthetic fatty alcohols can be obtained by oxidation of alkyl aluminum by Ziegler method or by carbonyl synthesis; natural fatty alcohols can be obtained by extraction from oils and fats; specifically, the fatty alcohols include fatty alcohols containing a single carbon atom, such as C12 alcohol, C14 alcohol, C16 alcohol, C18 alcohol, C20 alcohol, C22 alcohol, C24 alcohol, C26 alcohol, C28 alcohol, C30 alcohol; and mixed fatty alcohols containing different numbers of carbon atoms, such as C12-18 mixed alcohol, C16-18 mixed alcohol, C16-22 mixed alcohol, one or more of which are selected; the amount of fatty alcohol used accounts for 10-20% of the total amount of the emulsion.

[0007] B. Paraffin The paraffin is a hydrocarbon extracted from petroleum, shale oil or other asphalt mineral oil, selected from microcrystalline paraffin and liquid paraffin. The amount of paraffin accounts for 2-8% of the total amount of the emulsion.

[0008] C. Grease The oil is selected from one or more of rapeseed oil, peanut oil, soybean oil, coconut oil, palm oil, castor oil, olive oil and butter. The amount of the oil accounts for 2-8% of the total amount of the emulsion.

[0009] D. Modified silica The modified silica is obtained by surface-modifying silica with a silane coupling agent, and the amount of the modified silica accounts for 2-6% of the total amount of the emulsion; The preparation method of modified silica comprises the following steps: adding a silane coupling agent and water into a reaction container, adjusting the pH value to between 4 and 6 by using an acid, stirring evenly, adding silica and a solvent, stirring at a high speed of 1000-2000 r / min for 2-5 minutes, filtering and drying to obtain the modified silica; wherein the silane coupling agent is selected from KH550, KH560, KH570, KH580 and KH590; the silica is hydrophobic silica selected from precipitated hydrophobic silica and vapor phase hydrophobic silica; the amount of the silane coupling agent is 0.5-2% of the total mass of the silica; the acid is selected from acetic acid, oxalic acid, phosphoric acid and silicic acid; the solvent is selected from acetone, ketone, ethanol, cyclohexane water and the amount of the acetone solvent is sufficient for the reaction.

[0010] E. Nonionic surfactant The nonionic surfactant is obtained by compounding surfactant M and surfactant N; wherein the structural formula of nonionic surfactant M is: R 1 O(EO) m H, where R 1 C 8-28 alkyl, m is an integer of 10-60; the nonionic surfactant N is selected from one or more of polyoxyethylene sorbitan monostearate (Tween60), polyoxyethylene sorbitan monooleate (Tween80), polyoxyethylene sorbitan trioleate (Tween85), sorbitan monolaurate (Span20), sorbitan monopalmitate (Span40), sorbitan monostearate (Span60), tristearic acid glyceryl, monostearic acid glyceryl, pentaerythritol stearic acid glyceryl, ethylene glycol monostearate, ethylene glycol distearate, diethylene glycol monostearate, and diethylene glycol distearate; The amount of the nonionic surfactant used accounts for 2-10% of the total amount of the emulsion; wherein the amount of the nonionic surfactant M accounts for 50-90% of the total mass of the nonionic surfactant.

[0011] F. Acrylate polymer The amount of the acrylic ester polymer is 2-5% of the total amount of the emulsion.

[0012] The preparation method of the acrylate polymer comprises the following steps: adding different types of acrylate monomers into a reaction container, adding a benzoyl peroxide catalyst dropwise while stirring, and reacting for 2-8 hours at a temperature of 60-100° C.; the acrylate monomers are selected from two or more of hydroxyethyl acrylate, methyl acrylate, ethyl acrylate, butyl acrylate, lauryl acrylate, octadecyl acrylate, and isooctyl acrylate, and the mixture is selected in any proportion; and the amount of the catalyst used accounts for 0.2-2% of the total mass of the acrylate monomers.

[0013] G. Water In the present invention, the amount of water used accounts for 60-75% of the total amount of the emulsion; the water is used in two parts, and G1 accounts for 10-30% of the total mass of the water.

[0014] A method for preparing a stable fatty alcohol emulsion defoamer is as follows: (1) Modified silica D and water G1 are mixed and stirred to obtain a dispersion H;.

[0015] (2) The acrylic polymer F, the nonionic surfactant M and the nonionic surfactant N are mixed and stirred uniformly to form a mixture I;.

[0016] (3) Mix fatty alcohol A, paraffin B and oil C, heat to 70-90°C, melt and stir evenly, add mixture I, keep warm and continue stirring evenly to obtain mixture J;.

[0017] (4) Keep the mixture warm and continue to add the dispersion H to the mixture J. After stirring evenly, continue to add the remaining amount of water G2. After stirring evenly, cool to room temperature to form an emulsion. DETAILED DESCRIPTION

[0018] Examples of modified silica

[0019] Acrylate polymer examples and comparative examples

[0020] Fatty alcohol emulsion defoamer embodiment Example 1

[0021] (1) 5 g of modified silica D1 and 6 g of water were mixed and stirred to obtain a dispersion H1; (2) 2g of acrylic acid polymer F1 and 5g of nonionic surfactant C 8 H 17 O(EO) 60 H, 5g of the nonionic surfactant Tween60 and Span60 mixture were mixed and stirred to form a mixture I1; (3) a mixture of 10 g of C12-18 mixed alcohol, 5 g of microcrystalline paraffin, 8 g of rapeseed oil and peanut oil was heated to 70°C and melted and stirred evenly, and mixture I1 was added thereto, and the mixture was kept warm and stirred evenly to obtain mixture J1; (4) Continue to add dispersion H1 to mixture J1 while keeping the temperature high. After stirring evenly, continue to add the remaining 54 g of water. After stirring evenly, cool to room temperature to form an emulsion. Example 2

[0022] (1) 2 g of modified silica D2 and 8 g of water were mixed and stirred to obtain a dispersion H2; (2) 5 g of acrylic acid polymer F2 and 4.8 g of nonionic surfactant C 15 H 31 O(EO) 40 H, 3.2 g of nonionic surfactant Tween 80 and glyceryl tristearate were mixed and stirred to form a mixture I2; (3) Mix 20 g of C16-18 mixed alcohol, 2 g of liquid paraffin, 2 g of soybean oil and coconut oil, heat to 80°C, melt and stir evenly, add mixture I2, keep warm and continue stirring evenly to obtain mixture J2; (4) Continue to add dispersion H2 to mixture J2 while keeping the temperature high. After stirring evenly, continue to add the remaining 53 g of water. After stirring evenly, cool to room temperature to form an emulsion. Example 3

[0023] (1) 3 g of modified silica D3 and 15 g of water were mixed and stirred to obtain a dispersion H3; (2) 3 g of acrylic acid polymer F3 and 4.2 g of nonionic surfactant C 20 H 41 O(EO) 20 H, 1.8g of a mixture of nonionic surfactant glyceryl monostearate and pentaerythritol stearate were mixed and stirred to form a mixture I3; (3) a mixture of 14 g C16-22 mixed alcohol, 6 g microcrystalline paraffin, 4 g castor oil and olive oil was heated to 90°C and melted and stirred evenly, and mixture I3 was added thereto, and the mixture was kept warm and stirred evenly to obtain mixture J3; (4) Keep the mixture warm and continue to add the dispersion H3 to the mixture J3. After stirring evenly, continue to add the remaining 49 g of water. After stirring evenly, cool to room temperature to form an emulsion. Example 4

[0024] (1) 6 g of modified silica D4 and 19 g of water were mixed and stirred to obtain a dispersion H4; (2) 4 g of acrylic acid polymer F4 and 1.6 g of nonionic surfactant C 25 H 51 O(EO) 10 H, 0.4g of nonionic surfactant ethylene glycol monostearate were mixed and stirred to form a mixture I4; (3) 11 g of a mixture of C18 alcohol and C12 alcohol, 8 g of liquid paraffin, and 3 g of soybean oil were mixed and heated to 75°C until they melted and stirred evenly, and mixture I4 was added thereto. The mixture was kept warm and stirred evenly to obtain mixture J4; (4) Continue to add dispersion H4 to mixture J4 while keeping the temperature high. After stirring evenly, continue to add the remaining 47 g of water. After stirring evenly, cool to room temperature to form an emulsion. Example 5

[0025] (1) 2 g of modified silica D5 and 22.5 g of water were mixed and stirred to obtain a dispersion H5; (2) 2 g of acrylic acid polymer F5 and 2.7 g of nonionic surfactant C 28 H 57 O(EO) 30 H, 0.3g of a mixture of ethylene glycol distearate and diethylene glycol monostearate, a nonionic surfactant, were mixed and stirred to form a mixture I5; (3) 13 g of a mixture of C30 alcohol and C28 alcohol, 2 g of microcrystalline paraffin, and 3 g of a mixture of palm oil and tallow were mixed and heated to 85° C. and melted and stirred evenly, and mixture I5 ​​was added thereto. The mixture was kept warm and stirred evenly to obtain mixture J5; (4) Continue to add dispersion H5 to mixture J5 while keeping the temperature high. After stirring evenly, continue to add the remaining 52.5 g of water. After stirring evenly, cool to room temperature to form an emulsion. Example 6

[0026] (1) 3 g of modified silica D1 and 14 g of water were mixed and stirred to obtain a dispersion H6; (2) 3g of acrylic acid polymer F1 and 2g of nonionic surfactant C 12 H 25 O(EO) 15 H, 2 g of a mixture of nonionic surfactants Span20, Span40 and Tween85 were mixed and stirred to form a mixture I6; (3) 13 g of a mixture of C12 alcohol and C14 alcohol, 3 g of microcrystalline paraffin, and 4 g of castor oil were mixed and heated to 80° C. and stirred to melt, and mixture I6 was added thereto. The mixture was kept warm and stirred to obtain mixture J6; (4) Continue to add dispersion H6 to mixture J6 while keeping the temperature high. After stirring evenly, continue to add the remaining 56 g of water. After stirring evenly, cool to room temperature to form an emulsion.

[0027] Comparative Example 1 (1) 5 g of unmodified silica and 6 g of water were mixed and stirred to obtain a dispersion H7; (2) 2g of acrylic acid polymer F1 and 5g of nonionic surfactant C 8 H 17 O(EO) 60H, 5g of the nonionic surfactant Tween60 and Span60 mixture were mixed and stirred to form a mixture I1; (3) a mixture of 10 g of C12-18 mixed alcohol, 5 g of microcrystalline paraffin, 8 g of rapeseed oil and peanut oil was heated to 70°C and melted and stirred evenly, and mixture I1 was added thereto, and the mixture was kept warm and stirred evenly to obtain mixture J1; (4) Keep the mixture warm and continue to add the dispersion H7 to the mixture J1. After stirring evenly, continue to add the remaining 54 g of water. After stirring evenly, cool to room temperature to form an emulsion.

[0028] Comparative Example 2 (1) 5 g of acrylic acid polymer F2 and 4.8 g of nonionic surfactant C 15 H 31 O(EO) 40 H, 3.2 g of nonionic surfactant Tween 80 and glyceryl tristearate were mixed and stirred to form a mixture I2; (2) Mix 22 g of C16-18 mixed alcohol, 2 g of liquid paraffin, 2 g of soybean oil and coconut oil, heat to 80°C, melt and stir evenly, add mixture I2, keep warm and continue stirring evenly to obtain mixture J7; (3) Continue to add 61 g of water to the mixture J7 while keeping the temperature high. Stir well and then cool to room temperature to form an emulsion.

[0029] Comparative Example 3 (1) 3 g of modified silica D3 and 15 g of water were mixed and stirred to obtain a dispersion H3; (2) Add 6.2 g of nonionic surfactant C 20 H 41 O(EO) 20 H, 2.8g of a mixture of nonionic surfactant glyceryl monostearate and pentaerythritol stearate were mixed and stirred to form a mixture I7; (3) a mixture of 14 g C16-22 mixed alcohol, 6 g microcrystalline paraffin, 4 g castor oil and olive oil was heated to 90°C and melted and stirred evenly, and mixture I7 was added thereto, and the mixture was kept warm and stirred evenly to obtain mixture J8; (4) Keep the mixture warm and continue to add the dispersion H3 to the mixture J8. After stirring evenly, continue to add the remaining 49 g of water. After stirring evenly, cool to room temperature to form an emulsion.

[0030] Comparative Example 4 (1) 6 g of modified silica D4 and 19 g of water were mixed and stirred to obtain a dispersion H4; (2) 4 g of acrylic polymer F4 and 2 g of nonionic surfactant ethylene glycol monostearate were mixed and stirred to form a mixture I8; (3) 11 g of a mixture of C18 alcohol and C12 alcohol, 8 g of liquid paraffin, and 3 g of soybean oil were mixed and heated to 75°C until they melted and stirred evenly, and mixture I8 was added thereto. The mixture was kept warm and stirred evenly to obtain mixture J9; (4) Keep warm and continue to add dispersion H4 to mixture J9. After stirring evenly, continue to add the remaining 47 g of water. After stirring evenly, cool to room temperature to form an emulsion.

[0031] Comparative Example 5 (1) 2 g of modified silica D5 and 22.5 g of water were mixed and stirred to obtain a dispersion H5; (2) 2g of acrylic acid polymer F5 and 3g of nonionic surfactant C 28 H 57 O(EO) 30 H mixed and stirred evenly to form a mixture I9; (3) 13 g of a mixture of C30 alcohol and C28 alcohol, 2 g of microcrystalline wax, and 3 g of a mixture of palm oil and tallow were mixed and heated to 85°C and melted and stirred uniformly, and mixture I9 was added thereto, and the mixture was kept warm and stirred uniformly to obtain mixture J10; (4) Continue to add dispersion H5 to mixture J10 while keeping the temperature high. After stirring evenly, continue to add the remaining 52.5 g of water. After stirring evenly, cool to room temperature to form an emulsion.

[0032] Performance Testing 1. Emulsion stability test The emulsions prepared in the above examples and comparative examples were placed at 5°C, 25°C, and 40°C for 6-month viscosity tracking tests. The specific viscosity test method uses a NDJ-8 digital display viscometer, 2# rotor, and 6rpm conditions for testing. The specific situation is shown in Table 1 below (viscosity unit mPa.s, "-" means the emulsion is a paste and cannot flow):

[0033] From the viscosity tracking test data, it can be seen that the viscosity of the defoamer emulsion prepared by the present invention is slightly changed when stored at 5°C, 25°C and 40°C for 6 months, showing good storage stability. The viscosity of the fatty alcohol emulsions prepared in Comparative Examples 1-5 increases to varying degrees after 6 months.

[0034] 2. Test method for foam suppression performance: The performance of the defoaming agent is determined by the circulating bubbling method. 600 ml of white water is added to the circulating bubbling device and heated to the required temperature. The flow pump is turned on and circulated at a flow rate of 8 / L min to a foam volume of 300 ml. 6 ul of defoaming agent is added and the change of foam volume over time is recorded. Within the same time, the smaller the volume, the better the defoaming and antifoaming performance; the longer the time for the foam to reach 300 ml again, the better the antifoaming performance.

[0035]

[0036]

[0037] The fatty alcohol emulsion prepared by the invention exhibits good foam elimination and suppression performance at 30°C and 55°C.

Claims

1. A method for preparing a stable fatty alcohol emulsion, comprising the following components: A. Fatty alcohol The fatty alcohol is a monohydric to trihydric alcohol of C12-C30, selected from one or a mixture of synthetic fatty alcohols and natural fatty alcohols; the synthetic fatty alcohol can be obtained by oxidation of alkyl aluminum by the Ziegler method, or by carbonyl synthesis; the natural fatty alcohol can be obtained by extraction from oils and fats; specifically, the fatty alcohol includes fatty alcohols containing a single carbon atom, such as C12 alcohol, C14 alcohol, C16 alcohol, C18 alcohol, C20 alcohol, C22 alcohol, C24 alcohol, C26 alcohol, C28 alcohol, C30 alcohol; and mixed fatty alcohols containing different numbers of carbon atoms, such as C12-18 mixed alcohol, C16-18 mixed alcohol, C16-22 mixed alcohol, one or more of which are selected; the amount of fatty alcohol used accounts for 10-20% of the total amount of the emulsion; B. Paraffin The paraffin is a hydrocarbon extracted from petroleum, shale oil or other asphalt mineral oil, selected from microcrystalline paraffin and liquid paraffin; the amount of paraffin accounts for 2-8% of the total amount of the emulsion; C. Grease The oil is selected from one or more of rapeseed oil, peanut oil, soybean oil, coconut oil, palm oil, castor oil, olive oil and butter; the amount of oil accounts for 2-8% of the total amount of the emulsion; D. Modified silica The modified silica is obtained by surface-modifying silica with a silane coupling agent, and the amount of the modified silica accounts for 2-6% of the total amount of the emulsion; E. Nonionic surfactant The nonionic surfactant is obtained by compounding surfactant M and surfactant N; wherein the structural formula of nonionic surfactant M is: R1O(EO) m H, where R1 is C 8-28 alkyl, m is an integer of 10-60; the nonionic surfactant N is selected from one or more of polyoxyethylene sorbitan monostearate (Tween60), polyoxyethylene sorbitan monooleate (Tween80), polyoxyethylene sorbitan trioleate (Tween85), sorbitan monolaurate (Span20), sorbitan monopalmitate (Span40), sorbitan monostearate (Span60), tristearic acid glyceryl, monostearic acid glyceryl, pentaerythritol stearic acid glyceryl, ethylene glycol monostearate, ethylene glycol distearate, diethylene glycol monostearate, and diethylene glycol distearate; the amount of the nonionic surfactant is 2-10% of the total amount of the emulsion; F, acrylate polymer, the acrylate polymer is used in an amount of 2-5% of the total amount of the emulsion; G. Water The amount of water used accounts for 60-75% of the total amount of the emulsion; the water is used in two parts, G1 and G2; A method for preparing a stable fatty alcohol emulsion defoamer is as follows: (1) Mixing and stirring the modified silica D and water G1 to obtain a dispersion H; (2) mixing and stirring the acrylic polymer F, the nonionic surfactant M, and the nonionic surfactant N to form a mixture I; (3) Mix fatty alcohol A, paraffin B, and oil C, heat to 70-90°C, melt and stir evenly, add mixture I, keep warm and continue stirring evenly to obtain mixture J; (4) Keep the mixture warm and continue to add the dispersion H to the mixture J. After stirring evenly, continue to add the remaining amount of water G2. After stirring evenly, cool to room temperature to form an emulsion.

2. The method for preparing a stable fatty alcohol emulsion defoamer according to claim 1, characterized in that: The preparation method of the modified silica comprises the following steps: adding a silane coupling agent and water into a reaction container, adjusting the pH value to between 4 and 6 with an acid, stirring evenly, adding silica and a solvent, stirring at a high speed of 1000 to 2000 r / min for 2 to 5 minutes, filtering and drying to obtain the modified silica; wherein the silane coupling agent is selected from KH550, KH560, KH570, KH580, and KH590; the silica is hydrophobic silica selected from precipitated hydrophobic silica and vapor phase hydrophobic silica; the amount of the silane coupling agent is 0.5 to 2% of the total mass of the silica; the acid is selected from acetic acid, oxalic acid, phosphoric acid, and silicic acid; the solvent is selected from acetone, ketone, ethanol, cyclohexane water, and the amount of the acetone solvent is sufficient for the reaction.

3. The method for preparing a stable fatty alcohol emulsion defoamer according to claim 1, characterized in that: The amount of the nonionic surfactant M accounts for 50-90% of the total mass of the nonionic surfactant.

4. The method for preparing a stable fatty alcohol emulsion defoamer according to claim 1, characterized in that: The preparation method of the acrylate polymer comprises the following steps: adding different types of acrylate monomers into a reaction container, adding a benzoyl peroxide catalyst dropwise while stirring, and reacting for 2-8 hours at a temperature of 60-100° C.; the acrylate monomers are selected from two or more of hydroxyethyl acrylate, methyl acrylate, ethyl acrylate, butyl acrylate, lauryl acrylate, octadecyl acrylate, and isooctyl acrylate, and the mixture is selected in any proportion; and the amount of the catalyst used accounts for 0.2-2% of the total mass of the acrylate monomers.

5. The method for preparing a stable fatty alcohol emulsion defoamer according to claim 1, characterized in that: Water G1 accounts for 10-30% of the total water mass.

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