High-temperature-resistant stable fatty alcohol defoaming agent and preparation method thereof

Abstract

The invention discloses a high-temperature-resistant stable fatty alcohol defoaming agent and a preparation method thereof.According to the high-temperature-resistant stable fatty alcohol defoaming agent and the preparation method thereof, the high stability of the fatty alcohol defoaming agent can be effectively guaranteed, the water dispersibility and lipophilicity of the defoaming agent can be effectively improved by controlling and adjusting the amount-of-substance ratio of ethylene oxide to propylene oxide, and meanwhile the defoaming speed of the defoaming agent is guaranteed; when the carbon chain length of the polyether initiator is 18-22, the fatty alcohol polyether ester defoaming agent shows better defoaming performance, and especially when the polyether initiator is octadecanol, the foam eliminating and inhibiting effect is optimal; when the proportion of PO is too high, the cloud point of octadecanol polyether is too low, and corresponding polyether ester is more hydrophobic, so that the defoaming performance is more excellent; the polyether initiator is octadecanol, the relative molecular mass is 2000, the molar ratio of EO to PO is 3: 7, fatty alcohol polyether ester synthesized by stearic acid serves as fatty acid, the defoaming performance in white water is good, and polyether ester synthesized by glyceryl polyether can have both water dispersibility and defoaming performance.

Description

Technical Field

[0001] The present invention relates to the technical field of defoamers, and more specifically, to a high-temperature stable fatty alcohol defoamer and a preparation method thereof. Background Art

[0002] Fatty alcohol defoamers generally consist of multiple components with different functions, namely main antifoaming agents, carriers, emulsifiers, stabilizers, etc. Since fatty alcohol defoamers do not contain silicon, silicon residues will not be caused.

[0003] Fatty alcohol defoamers are polymerized from fatty alcohols and the like through a special process. They can quickly penetrate into the liquid interior and rapidly spread, eliminating stubborn foams generated by various surfactants. Fatty alcohol defoamers have a wide range of uses and application fields, and are used for defoaming in the pulping, papermaking, industrial cleaning, coating process, degreasing agent, metal grinding fluid, coating, cutting fluid, chemical fiber oil agent, water-based ink, adhesive, pesticide, chemical industry, sewage treatment, knitting oil agent, and ore washing processes. Generally, high-carbon alcohols are used for degassing and polyethers are used to eliminate surface foams in papermaking white water. In industrial production, polyether esters can both degas and eliminate surface foams, combining the advantages of high-carbon alcohol defoamers and polyether defoamers.

[0004] After polyethers and fatty acids are esterified, the length of the fatty acid carbon chain determines the characteristics of polyether fatty acid esters, such as lipophilicity, etc., which has a certain impact on foam control. At the same time, the molar ratio of ethylene oxide (EO) to propylene oxide (PO) in the polyether also affects the water dispersibility of polyether fatty acid esters. When the proportion of EO is large, the water dispersibility increases, but the defoaming property decreases; when the proportion of PO is large, the water dispersibility decreases, the lipophilicity increases, which is beneficial to defoaming and foam control, but if the ratio of nPO:nEO is too large, it will affect the diffusion of the defoamer into the foam and the defoaming speed will decrease. Summary of the Invention

[0005] In order to overcome the above-mentioned defects of the prior art, an embodiment of the present invention provides a high-temperature stable fatty alcohol defoamer and a preparation method thereof.

[0006] A high-temperature stable fatty alcohol defoamer, the raw materials calculated by weight percentage include: 15.2% - 15.8% of fatty alcohol complex, 6.7% - 7.3% of paraffin, 5.6% - 6.4% of emulsifier, 0.2% - 0.4% of thickener, and the rest is deionized water.

[0007] Further, the raw materials of the fatty alcohol complex include: fatty alcohol polyether, fatty acid, glycerol polyether, p-toluenesulfonic acid.

[0008] Furthermore, the molar ratio of the fatty alcohol polyether, fatty acid, and glycerol polyether is 1∶(3 - 5)∶1; the dosage of p-toluenesulfonic acid is 0.15% - 0.25% of the total weight of the fatty alcohol polyether, fatty acid, and glycerol polyether.

[0009] Furthermore, the fatty alcohol polyether is octadecanol polyether (with octadecanol as the initiator, relative molecular mass of 2000, and the molar ratio of ethylene oxide (EO) to propylene oxide (PO) being 3∶7); the fatty acid is stearic acid, and the relative molecular mass of the glycerol polyether is 2000 - 4000, with the molar ratio of ethylene oxide (EO) to propylene oxide (PO) being 2∶8.

[0010] Furthermore, the composite emulsifier is prepared by compounding sorbitan fatty acid ester Span40 and polyoxyethylene sorbitan fatty acid ester Tween80 in a weight ratio of (3.5 - 4.5)∶1.

[0011] Furthermore, the raw materials of the thickener include acrylic acid, fatty alcohol polyoxyethylene ether methacrylate, and a UV photoinitiator.

[0012] A high-temperature stable fatty alcohol defoamer, step one: Weigh octadecanol polyether, stearic acid, glycerol polyether, p-toluenesulfonic acid, sorbitan fatty acid ester Span40, polyoxyethylene sorbitan fatty acid ester Tween80, acrylic acid, fatty alcohol polyoxyethylene ether methacrylate, UV photoinitiator, paraffin wax, and deionized water;

[0013] Step two: Add octadecanol polyether, stearic acid, and glycerol polyether into a reaction vessel, stir, and heat. When the temperature rises to 75 - 85°C, add p-toluenesulfonic acid. After vacuum treatment, continue heating to 135 - 145°C, keep warm for 4 hours, then cool down to 55 - 65°C, add sodium bicarbonate to neutralize p-toluenesulfonic acid, and continue stirring and cooling to room temperature to obtain a fatty alcohol complex;

[0014] Step three: Add acrylic acid into pure water, then slowly drip sodium hydroxide solution, and cool with cold water to obtain a neutralized solution of alkaline sodium acrylate;

[0015] Step four: Add fatty alcohol polyoxyethylene ether methacrylate into pure water, stir evenly to prepare a BEM aqueous solution;

[0016] Step five: Slowly drip the BEM aqueous solution into the neutralized solution of alkaline sodium acrylate, stir while dripping to prepare a glue containing a certain amount of BEM, then add a UV photoinitiator, stir evenly, and carry out UV photocuring for 2 - 3 hours to obtain a thickener;

[0017] Step six: Add the thickener obtained in step five into one-fifth weight portion of deionized water, stir evenly to obtain a thickener aqueous solution;

[0018] Step 7: Add sorbitan fatty acid ester Span40 and polyoxyethylene sorbitan fatty acid ester Tween80 into a beaker, heat to 55 - 65°C and stir for 1 hour to obtain a composite emulsifier;

[0019] Step 8: Add the fatty alcohol complex, paraffin, composite emulsifier, and the remaining deionized water into a reaction vessel, heat with water bath and stir to 65 - 75°C and maintain for 3 hours, slowly dropwise add the thickener aqueous solution, maintain at 70 - 80°C and stir for 1 hour; finally, use a high-speed shear emulsifier to shear at a rotation speed of 10000 - 12000 r / min for 10 - 20 minutes to obtain a high-temperature stable fatty alcohol defoamer.

[0020] Further, in Step 2, evacuate to keep the pressure below -0.095 MPa, and the stirring speed is 120 - 180 r / min.

[0021] Further, in Step 3, the neutralization degree of the basic sodium acrylate neutralized solution is 80% and the solid content is 38%.

[0022] Further, in Step 4, the mass fraction of the BEM aqueous solution is 0.12% - 0.18%; in Step 5, the content of BEM in the glue is 0.7% - 1.6%; the addition amount of the UV photoinitiator is 0.04% - 0.05% of the total mass of the glue.

[0023] The technical effects and advantages of the present invention:

[0024] 1. The high-temperature stable fatty alcohol defoamer prepared by using the raw material formula of the present invention can effectively ensure the high stability of the fatty alcohol defoamer. By controlling and adjusting the molar ratio of ethylene oxide (EO) to propylene oxide (PO), the water dispersibility and lipophilicity of the defoamer can be effectively improved, while ensuring the defoaming speed of the defoamer; when the carbon chain length of the polyether initiator is 18 - 22, the fatty alcohol polyether ester defoamer shows better defoaming performance. Especially when the polyether initiator is octadecanol, the defoaming and foam suppression effect is the best; when the PO ratio is on the high side (exceeding 70%), the cloud point of octadecanol polyether is low, and the corresponding polyether ester is more hydrophobic, so the defoaming performance is more excellent; the fatty alcohol polyether ester synthesized from octadecanol (relative molecular mass 2000, molar ratio of EO to PO is 3:7) and stearic acid has good defoaming performance in white water. The polyether ester synthesized from glycerol polyether with a relative molecular mass of about 2000 and a molar ratio of EO to PO of 2:8 can balance the water dispersibility and defoaming and foam suppression performance;

[0025] 2. The thickener in the present invention has high viscosity, large thixotropy and strong salt resistance; fatty alcohol polyoxyethylene ether methacrylate (BEM) is a good modifier for sodium polyacrylate thickener; as the content of fatty alcohol polyoxyethylene ether methacrylate (BEM) increases, its viscosity, salt resistance, thixotropy, moisture retention and weather resistance are all significantly improved; when the content of fatty alcohol polyoxyethylene ether methacrylate (BEM) is relatively high, the hydrophobic groups undergo intermolecular association to form a dynamic physical crosslinking network, which can lock water molecules and make them not easy to evaporate, effectively improving the high stability of the fatty alcohol defoamer; fatty alcohol polyoxyethylene ether methacrylate (BEM) contains both hydrophobic groups to cause association, and at the same time it also contains hydrophilic groups to increase its hydrophilicity, and its solubility is very good, and it can be completely dissolved into a transparent solution in aqueous solution and alkaline glue solution, and can be directly copolymerized in aqueous solution; when NaCl is introduced into the solution, the addition of electrolytes can enhance the polarity of the aqueous solution, increase the aggregation of hydrophobic groups, increase intermolecular association, and increase the viscosity, thereby improving the salt resistance of the thickener and further improving the salt resistance and stability of the defoamer. Detailed implementation mode

[0026] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0027] Example 1:

[0028] The present invention provides a high-temperature stable fatty alcohol defoamer, and the raw materials include, calculated by weight percentage: 15.2% of fatty alcohol complex, 6.7% of paraffin, 5.6% of emulsifier, 0.2% of thickener, and 72.3% of deionized water;

[0029] The raw materials of the fatty alcohol complex include: fatty alcohol polyether, fatty acid, glycerol polyether, p-toluenesulfonic acid; the molar ratio of the fatty alcohol polyether, fatty acid, and glycerol polyether is 1:3:1; the dosage of p-toluenesulfonic acid is 0.15% of the total weight of the fatty alcohol polyether, fatty acid, and glycerol polyether;

[0030] The fatty alcohol polyether is octadecanol polyether (the starting agent is octadecanol, the relative molecular mass is 2000, and the molar ratio of ethylene oxide (EO) to propylene oxide (PO) is 3:7); the fatty acid is stearic acid, and the relative molecular mass of the glycerol polyether is 3000, and the molar ratio of ethylene oxide (EO) to propylene oxide (PO) is 2:8;

[0031] The composite emulsifier is prepared by compounding sorbitan fatty acid ester Span40 and polyoxyethylene sorbitan fatty acid ester Tween80 according to a weight ratio of 3.5:1;

[0032] Preparation method of high-temperature stable fatty alcohol defoamer, and the specific preparation steps are as follows:

[0033] Step 1: Weigh polyoxyethylene octadecanol ether, stearic acid, glycerol polyether, p-toluenesulfonic acid, sorbitan fatty acid ester Span40, polyoxyethylene sorbitan fatty acid ester Tween80, acrylic acid, fatty alcohol polyoxyethylene ether methacrylate, UV photoinitiator, paraffin wax, deionized water;

[0034] Step 2: Add polyoxyethylene octadecanol ether, stearic acid, and glycerol polyether into a reaction vessel, stir and heat. When the temperature rises to 80°C, add p-toluenesulfonic acid. After vacuum treatment, continue heating to 140°C and keep the temperature for 4 hours. Then cool down to 60°C, add sodium bicarbonate to neutralize p-toluenesulfonic acid, and continue stirring and cooling to room temperature to obtain a fatty alcohol complex; Keep the vacuum pressure below -0.095 MPa, and the stirring speed is 150 r / min;

[0035] Step 3: Add acrylic acid into pure water, and then slowly dropwise add sodium hydroxide solution, and cool with cold water to obtain a neutralized solution of alkaline sodium acrylate; The neutralization degree of the neutralized solution of alkaline sodium acrylate is 80% and the solid content is 38%;

[0036] Step 4: Add fatty alcohol polyoxyethylene ether methacrylate into pure water and stir evenly to prepare an aqueous BEM solution; The mass fraction of the aqueous BEM solution is 0.15%;

[0037] Step 5: Slowly dropwise add the aqueous BEM solution into the neutralized solution of alkaline sodium acrylate, stir while dropping, and prepare a glue containing a certain amount of BEM. The content of BEM in the glue is 1.15%. Then add a UV photoinitiator, stir evenly, and carry out UV photocuring for 2.5 hours to obtain a thickener; The addition amount of the UV photoinitiator is 0.045% of the total mass of the glue;

[0038] Step 6: Add the thickener in Step 5 into one-fifth part by weight of deionized water and stir evenly to obtain an aqueous thickener solution;

[0039] Step 7: Add sorbitan fatty acid ester Span40 and polyoxyethylene sorbitan fatty acid ester Tween80 into a beaker, heat to 60°C and stir for 1 hour to obtain a composite emulsifier;

[0040] Step 8: Add the fatty alcohol complex, paraffin wax, compound emulsifier, and the remaining deionized water into a reaction vessel, heat with stirring in a water bath to 75°C and maintain for 3 hours, slowly dropwise add the thickener aqueous solution, maintain at 75°C and stir for another 1 hour; finally, use a high-speed shear emulsifier to shear at a speed of 11,000 r / min for 15 minutes to obtain a high-temperature stable fatty alcohol defoamer;

[0041] Sorbitan fatty acid ester Span40 was purchased from Bostian Titanium Co., Ltd.; Polyoxyethylene sorbitan fatty acid ester Tween80 was purchased from Jin Kelong Co., Ltd.; Octadecanol polyether was purchased from Shandong Bluestar Dongda Chemical Co., Ltd., industrial grade; Stearic acid was purchased from Sinopharm Chemical Reagent Co., Ltd., analytical pure; Glycerol polyether was purchased from Jiangsu Zhongshan Chemical Co., Ltd., industrial grade; p-Toluenesulfonic acid was purchased from Shanghai Macklin Biochemical Co., Ltd., analytical pure; Acrylic acid was purchased from Sinopharm Chemical Reagent Co., Ltd., analytical pure; Fatty alcohol polyoxyethylene ether methacrylate was purchased from Shanghai Palimo New Materials Co., Ltd.; The UV photoinitiator was 1173 UV photoinitiator purchased from Huatai Chemical Co., Ltd., chemical pure; Paraffin wax was purchased from Abbexa (Shanghai) Biotech Co., Ltd., product number: abs42155596.

[0042] Example 2:

[0043] Different from Example 1, the raw materials calculated by weight percentage include: 15.8% of fatty alcohol complex, 7.3% of paraffin wax, 6.4% of emulsifier, 0.4% of thickener, 70.1% of deionized water;

[0044] The molar ratio of the fatty alcohol polyether, fatty acid, and glycerol polyether is 1:5:1; The dosage of p-toluenesulfonic acid is 0.25% of the total weight of the fatty alcohol polyether, fatty acid, and glycerol polyether;

[0045] The compound emulsifier is prepared by compounding sorbitan fatty acid ester Span40 and polyoxyethylene sorbitan fatty acid ester Tween80 in a weight ratio of 4.5:1.

[0046] Example 3:

[0047] Different from both Example 1 and Example 2, the raw materials calculated by weight percentage include: 15.5% of fatty alcohol complex, 7.0% of paraffin wax, 6.0% of emulsifier, 0.3% of thickener, 71.2% of deionized water;

[0048] The molar ratio of the fatty alcohol polyether, fatty acid, and glycerol polyether is 1:4:1; The dosage of p-toluenesulfonic acid is 0.20% of the total weight of the fatty alcohol polyether, fatty acid, and glycerol polyether;

[0049] The composite emulsifier is prepared by compounding sorbitan fatty acid ester Span40 and polyoxyethylene sorbitan fatty acid ester Tween80 according to a weight ratio of 4:1.

[0050] Comparative Example 1:

[0051] Different from Example 3: A high-temperature stable fatty alcohol defoamer, the fatty alcohol polyether is dodecanol polyether, the initiator is dodecanol, the relative molecular mass is 2000, and the molar ratio of ethylene oxide (EO) to propylene oxide (PO) is 3:7.

[0052] Comparative Example 2:

[0053] Different from Example 3: A high-temperature stable fatty alcohol defoamer, the fatty alcohol polyether is docosanol polyether, the initiator is docosanol, the relative molecular mass is 2000, and the molar ratio of ethylene oxide (EO) to propylene oxide (PO) is 3:7.

[0054] Comparative Example 3:

[0055] Different from Example 3: A high-temperature stable fatty alcohol defoamer, the fatty alcohol polyether is octadecanol polyether, the initiator is octadecanol, the relative molecular mass is 2000, and the molar ratio of ethylene oxide (EO) to propylene oxide (PO) is 5:5.

[0056] Comparative Example 4:

[0057] Different from Example 3: A high-temperature stable fatty alcohol defoamer, the fatty alcohol polyether is octadecanol polyether, the initiator is octadecanol, the relative molecular mass is 2000, and the molar ratio of ethylene oxide (EO) to propylene oxide (PO) is 7:3.

[0058] Comparative Example 5:

[0059] Different from Example 3: A high-temperature stable fatty alcohol defoamer, the relative molecular mass of the glycerol polyether is 1000, and the molar ratio of ethylene oxide (EO) to propylene oxide (PO) is 2:8.

[0060] Comparative Example 6:

[0061] Different from Example 3: A high-temperature stable fatty alcohol defoamer, the relative molecular mass of the glycerol polyether is 5000, and the molar ratio of ethylene oxide (EO) to propylene oxide (PO) is 2:8.

[0062] Comparative Example 7:

[0063] Different from Example 3: A high-temperature stable fatty alcohol defoamer, the thickener is sodium polyacrylate.

[0064] The high-temperature stable fatty alcohol defoamers in the comparative examples and examples of the present invention were tested:

[0065] The defoaming performance and foam suppression performance of the defoamer were tested, and the salt resistance and weather resistance of the thickener in the defoamer were tested;

[0066] Foam suppression performance: First, prepare 100 mL of a 1% sodium dodecylbenzenesulfonate aqueous solution, then pour it into a 500 mL graduated cylinder, and add 1 mL of the defoamer in the above-mentioned example or comparative example; Subsequently, nitrogen gas was introduced into the above solution at a flow rate of 2 L / min, and the time when the bubbles reached the 500 scale value was recorded as the foam suppression time; Each sample needs to be tested three times, and the average value is taken as the final foam suppression time.

[0067] Defoaming performance: First, prepare 100 mL of a 1% sodium dodecylbenzenesulfonate aqueous solution, then pour it into a 500 mL graduated cylinder, and nitrogen gas was introduced into the above solution until the 500 scale value; At this time, 1 mL of the emulsion defoamer was added dropwise, and the time required for the bubbles to disappear and the liquid surface to be exposed was recorded as the defoaming time; Each sample needs to be tested three times, and the average value is taken as the final defoaming time.

[0068] Salt resistance: Prepare an aqueous solution of the thickener with a mass fraction of 0.2%, measure the viscosity of the solution, and directly measure it with an NDJ-1 rotational viscometer (6 r / min), with the unit of mPa·s.

[0069] Measurement of salt resistance: The salt resistance is expressed by the retention rate M of the viscosity, and M is defined as

[0070] In the formula, n0—the viscosity of the solution measured without adding salt (usually using NaCl); n—the viscosity of the solution measured after adding salt;

[0071] Measurement of weather resistance: Prepare an aqueous solution of the thickener with a mass fraction of 0.2%, place it at a position with indirect sunlight indoors for 10 days, and observe the viscosity attenuation; Usually, the weather resistance is expressed by the attenuation rate of its viscosity;

[0073] In the formula, n0—the viscosity measured when the solution was just prepared; n1—the viscosity of the solution measured after being placed for 10 days.

[0074] The results are shown in Table 1:

[0075] Table 1:

[0076] Defoaming time (s) Anti-foaming time (min) Comparative Example 1 37 5.2 Comparative Example 2 28 5.8 Comparative Example 3 68 2.1 Comparative Example 4 86 1.7 Comparative Example 5 74 1.6 Comparative Example 6 47 5.9 Comparative Example 7 36 5.3 Example 1 26 5.9 Example 2 22 6.3 Example 3 15 7.4

[0077] Table 2:

[0078]

[0079] As can be seen from the above table, the high-temperature stable fatty alcohol defoamer of the present invention can effectively ensure the high stability of the fatty alcohol defoamer. By controlling and adjusting the molar ratio of ethylene oxide (EO) to propylene oxide (PO), the water dispersibility and lipophilicity of the defoamer can be effectively improved, while ensuring the defoaming speed of the defoamer.

[0080] In the present invention, when the carbon chain length of the polyether initiator is small, the hydrophobicity of the fatty alcohol polyether ester defoamer is weak. When the carbon chain length of the polyether initiator is large, the permeability of the fatty alcohol polyether ester defoamer to the foam liquid film is weakened, resulting in a decrease in its defoaming performance; when the carbon chain length of the polyether initiator is 18-22, the fatty alcohol polyether ester defoamer exhibits good defoaming performance. Especially when the polyether initiator is octadecanol, the defoaming and foam suppression effects are the best. When the proportion of PO is on the high side (exceeding 70%), the cloud point of octadecanol polyether is low, and the corresponding polyether ester is more hydrophobic, so the defoaming performance is more excellent; when the relative molecular mass of glycerol polyether is in the range of 2000-5000, the glycerol polyether ester has good dispersibility in water and fast defoaming speed. When the relative molecular mass is on the high side, the glycerol polyether ester has poor dispersibility in water, but the glycerol polyether ester defoamer has good continuous foam suppression effect; the polyether ester can quickly reduce the surface tension at a low mass concentration, and has excellent surface performance; the fatty alcohol polyether ester synthesized with octadecanol (relative molecular mass 2000, molar ratio of EO to PO is 3:7) as the polyether initiator and stearic acid as the fatty acid has good defoaming performance in white water; the polyether ester synthesized from glycerol polyether with a relative molecular mass of about 2000 and a molar ratio of EO to PO of 2:8 can balance the water dispersibility and defoaming and foam suppression performance. The fatty alcohol polyether ester defoamer is more resistant to low temperature (25-40 °C), and the glycerol polyether ester is more resistant to high temperature (≥40 °C);

[0081] This thickener has a high viscosity, large thixotropy, and strong salt resistance; fatty alcohol polyoxyethylene ether methacrylate (BEM) is a good modifier for sodium polyacrylate thickeners; as the content of fatty alcohol polyoxyethylene ether methacrylate (BEM) increases, its viscosity, salt resistance, thixotropy, moisture retention, and weather resistance are all significantly improved; when the content of fatty alcohol polyoxyethylene ether methacrylate (BEM) is relatively high, intermolecular association occurs among the hydrophobic groups, forming a dynamic physical crosslinking network, which can lock the water molecules and make them not easily evaporate, effectively improving the high stability of the fatty alcohol defoamer; the thixotropy of the solution is related to the intermolecular association of the hydrophobic groups, and the intermolecular association forms a dynamic physical crosslinking network with a relatively high viscosity; enough BEM can bring in enough hydrophilic groups to increase its viscosity; at the same time, a large number of hydrophobic groups are brought in, enabling it to produce intermolecular association; fatty alcohol polyoxyethylene ether methacrylate (BEM) contains both hydrophobic groups to produce association, and it also contains hydrophilic groups to increase its hydrophilicity, and its solubility is very good, completely dissolving into a transparent solution in aqueous solutions and alkaline glue solutions, and direct aqueous solution copolymerization can be carried out; when NaCl is introduced into the solution, the addition of electrolytes can enhance the polarity of the aqueous solution, increase the aggregation of hydrophobic groups, increase intermolecular association, and increase the viscosity, thereby improving the salt resistance of the thickener and further improving the salt resistance and stability of the defoamer.

[0082] The Span40 / Tween80 composite emulsifier has an efficient emulsifying effect, can be quickly dispersed in the emulsion, and significantly improves the defoaming and foam suppression effects; the emulsifier can form a thin film on the surface of the small droplets, thereby effectively maintaining the stable state of the emulsion.

[0083] In step two, add octadecyl alcohol polyether, stearic acid, and glycerol polyether to the reactor and stir and heat. Add p-toluenesulfonic acid as a catalyst, continue heating and maintaining the reaction in a vacuum environment, then add sodium bicarbonate to neutralize p-toluenesulfonic acid, and cool to room temperature to obtain a fatty alcohol complex; in step three, add acrylic acid to pure water and dropwise add sodium hydroxide solution to prepare the required alkaline sodium acrylate neutralization solution; in step four, add fatty alcohol polyoxyethylene ether methacrylate to pure water to make a BEM aqueous solution; in step five, react the BEM aqueous solution and the alkaline sodium acrylate neutralization solution, add a UV initiator, and carry out UV curing to prepare a thickener; in step six, prepare a thickener aqueous solution; in step seven, prepare a composite emulsifier; in step eight, mix the fatty alcohol complex, paraffin, composite emulsifier, and the remaining deionized water, add the thickener aqueous solution, stir and process, and then carry out shear emulsification to prepare a high-temperature stable fatty alcohol defoamer.

[0084] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments or perform equivalent replacements on some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A high-temperature resistant and stable fatty alcohol defoamer, characterized in that: The raw materials calculated by weight percentage include: 15.2% - 15.8% of fatty alcohol complex, 6.7% - 7.3% of paraffin wax, 5.6% - 6.4% of emulsifier, 0.2% - 0.4% of thickener, and the rest is deionized water.

2. The high-temperature stable fatty alcohol defoamer according to claim 1, characterized in that: The raw materials of the fatty alcohol complex include: fatty alcohol polyether, fatty acid, glycerol polyether, and p-toluenesulfonic acid.

3. The high-temperature stable fatty alcohol defoamer according to claim 2, wherein: The molar ratio of the fatty alcohol polyether, fatty acid, and glycerol polyether is 1∶(3 - 5)∶1; the dosage of the p-toluenesulfonic acid is 0.15% - 0.25% of the total weight of the fatty alcohol polyether, fatty acid, and glycerol polyether.

4. A high-temperature resistant and stable fatty alcohol defoamer according to claim 2, characterized in that: The fatty alcohol polyether is octadecyl alcohol polyether (the initiator is octadecyl alcohol, the relative molecular mass is 2000, and the molar ratio of ethylene oxide (EO) to propylene oxide (PO) is 3∶7); the fatty acid is stearic acid, and the relative molecular mass of the glycerol polyether is 2000 - 4000, and the molar ratio of ethylene oxide (EO) to propylene oxide (PO) is 2∶8.

5. A high-temperature resistant and stable fatty alcohol defoamer according to claim 1, characterized in that: The composite emulsifier is prepared by compounding sorbitan fatty acid ester Span40 and polyoxyethylene sorbitan fatty acid ester Tween80 in a weight ratio of (3.5 - 4.5)∶1.

6. The high-temperature stable fatty alcohol defoamer according to claim 1, characterized in that: The raw materials of the thickener include acrylic acid, fatty alcohol polyoxyethylene ether methacrylate, and UV photoinitiator.

7. A preparation method of a high-temperature resistant and stable fatty alcohol defoamer, characterized in that: The specific preparation steps are as follows: Step 1: Weigh octadecyl alcohol polyether, stearic acid, glycerol polyether, p-toluenesulfonic acid, sorbitan fatty acid ester Span40, polyoxyethylene sorbitan fatty acid ester Tween80, acrylic acid, fatty alcohol polyoxyethylene ether methacrylate, UV photoinitiator, paraffin wax, and deionized water; Step 2: Add octadecyl alcohol polyether, stearic acid, and glycerol polyether into a reaction vessel, stir and heat. When the temperature rises to 75 - 85°C, add p-toluenesulfonic acid. After vacuum treatment, continue heating to 135 - 145°C, keep warm for 4 hours, then cool down to 55 - 65°C, add sodium bicarbonate to neutralize the toluenesulfonic acid, and continue stirring and cooling to room temperature to obtain the fatty alcohol complex; Step 3: Add acrylic acid into pure water, then slowly dropwise add sodium hydroxide solution, and cool with cold water to obtain an alkaline sodium acrylate neutralization solution; Step 4: Add fatty alcohol polyoxyethylene ether methacrylate into pure water, stir evenly to prepare a BEM aqueous solution; Step 5: Slowly dropwise add the BEM aqueous solution into the alkaline sodium acrylate neutralization solution, stir while dropping to prepare a glue containing a certain amount of BEM, then add a UV photoinitiator, stir evenly, and carry out UV photocuring for 2 - 3 hours to obtain the thickener; Step 6: Add the thickener in Step 5 into one-fifth weight portion of deionized water, stir evenly to obtain a thickener aqueous solution; Step 7: Add sorbitan fatty acid ester Span40 and polyoxyethylene sorbitan fatty acid ester Tween80 into a beaker, heat to 55 - 65°C and stir for 1 hour to obtain the composite emulsifier; Step 8: Add the fatty alcohol complex, paraffin wax, compound emulsifier, and the remaining deionized water into the reaction vessel, heat and stir in a water bath to 65 - 75 °C and maintain for 3 hours, slowly dropwise add the thickener aqueous solution, maintain at 70 - 80 °C and stir for another 1 hour; finally, use a high-speed shear emulsifier to shear at a speed of 10000 - 12000 r / min for 10 - 20 minutes to obtain a high-temperature stable fatty alcohol defoamer.

8. The preparation method of a high-temperature resistant and stable fatty alcohol defoamer according to claim 7, characterized in that: In Step 2, evacuate to keep the pressure below -0.095 MPa, and the stirring speed is 120 - 180 r / min.

9. The preparation method of a high-temperature resistant and stable fatty alcohol defoamer according to claim 7, characterized in that: In Step 3, the neutralization degree of the basic sodium acrylate neutralization solution is 80% and the solid content is 38%.

10. The preparation method of a high-temperature resistant and stable fatty alcohol defoamer according to claim 7, characterized in that: In Step 4, the mass fraction of the BEM aqueous solution is 0.12% - 0.18%; in Step 5, the content of BEM in the glue is 0.7% - 1.6%; the addition amount of the UV photoinitiator is 0.04% - 0.05% of the total mass of the glue.

Images