Preparation method of modified bio-based polyether defoaming agent
The modified bio-based polyether defoamer prepared by reacting modified castor oil, glucose, and fatty alcohol polyether with stearate exhibits good defoaming and foam-suppressing effects in both aqueous and oily systems. This solves the problem of poor compatibility of defoamers in the prior art and achieves stable mixing with silicone paste and environmentally friendly defoamer preparation.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- JIANGSU ZHONGSHAN NEW MATERIALS CO LTD
- Filing Date
- 2026-02-13
- Publication Date
- 2026-04-10
AI Technical Summary
Existing polyether defoamers have poor defoaming effects in water-based and oil-based systems, and have poor compatibility with silicone paste, making them prone to separation and affecting their defoaming effect.
A modified bio-based polyether defoamer was prepared by esterification of modified castor oil, glucose, and fatty alcohol polyether with stearate. Through random copolymerization and esterification reaction, a mixture with good defoaming and foam-suppressing effects was formed.
Modified bio-based polyether defoamers exhibit excellent defoaming and foam-suppressing properties in both aqueous and oily systems. They are stable during storage when mixed with silicone paste, do not separate into layers, and are environmentally friendly.
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Abstract
Description
Technical Field
[0001] This invention belongs to the field of chemical additives technology, specifically relating to a method for preparing a modified bio-based polyether defoamer. Background Technology
[0002] In industrial production, the presence of excessive foam can severely disrupt normal operations, leading to a decrease in effective production volume, limited production capacity, increased raw material and product losses, and decreased product quality. It can also easily cause material spills, polluting the environment. Therefore, effectively controlling foam during production has become a key focus for researchers. Currently, defoamers are generally used to eliminate foam generated in industrial production.
[0003] Currently, polyether defoamers are the most widely used defoamers on the market. Polyether defoamers are characterized by low cost, simple production process, simple molecular structure, high product purity, good biocompatibility, and friendliness to the growth environment of industrial microorganisms. However, there is a lack of polyether defoamers that simultaneously exhibit good defoaming and foam-suppressing effects in both aqueous and oil-based systems. In industrial production, defoamers are rarely used alone; they are usually mixed with other components in the system (such as lubricants, thickeners, and carriers) before application. Silicone paste is a common compatibility matrix for defoamers. For example, in coatings, inks, and adhesives, silicone paste often exists as a thixotropic agent or lubricant, and the defoamer needs to be integrated into the system to function. In industrial cleaning, textile printing and dyeing, and other fields, silicone paste may serve as a "carrier component" in the formulation, and the defoamer needs to be dispersed integrally with it to avoid excessively high or low local concentrations. However, existing polyether defoamers have poor compatibility with silicone paste, easily causing stratification, which affects the defoaming effect. Summary of the Invention
[0004] The purpose of this invention is to provide a method for preparing a modified bio-based polyether defoamer. The resulting defoamer has good defoaming and foam-suppressing effects in both aqueous and oil-based systems, and also exhibits good miscibility with silicone paste and is stable during storage without stratification.
[0005] The objective of this invention is achieved through the following technical solution.
[0006] A method for preparing a modified bio-based polyether defoamer, comprising uniformly mixing the following components in parts by weight: 55-75 parts by weight of modified castor oil polyether A, 18-32 parts by weight of modified glucose polyether B, and 4-16 parts by weight of modified fatty alcohol polyether C.
[0007] In this invention, the modified castor oil polyether A is prepared by the following method: castor oil is used as an initiator to randomly copolymerize with ethylene oxide and propylene oxide to obtain castor oil polyether polyol A; using p-toluenesulfonic acid and hypophosphoric acid as catalysts, the castor oil polyether polyol A is esterified with stearic acid at a molar ratio of 1:1-1.6 to obtain modified castor oil polyether A.
[0008] In this invention, the castor oil polyether polyol A contains 10-20% ethylene oxide by mass and has a molecular weight of 2500-3500; the castor oil polyether polyol A is esterified with stearate at a temperature of 140-170°C and for a time of 6-10 hours.
[0009] In this invention, the modified glucose polyether B is prepared by the following method: glucose is used as an initiator to randomly copolymerize with ethylene oxide and propylene oxide to obtain glucose polyether polyol B; p-toluenesulfonic acid and hypophosphoric acid are used as catalysts to esterify glucose polyether polyol B with stearic acid at a molar ratio of 1:1-1:2 to obtain modified glucose polyether B.
[0010] In this invention, the ethylene oxide content in the glucose polyether polyol B is 10-15% by mass, and the molecular weight is 1500-2500; the esterification temperature of glucose polyether polyol B and stearic acid is 140-170℃, and the esterification time is 6-10h.
[0011] In this invention, the modified fatty alcohol polyether C is prepared by the following method: 1618 alcohol and lactic acid in a molar ratio of 1:1.2-2 are used as initiators and randomly copolymerized with ethylene oxide and propylene oxide to obtain fatty alcohol polyether C; p-toluenesulfonic acid and hypophosphoric acid are used as catalysts, and fatty alcohol polyether C is esterified with stearic acid in a molar ratio of 1:0.9-1.1 to obtain modified fatty alcohol polyether C.
[0012] In this invention, the fatty alcohol polyether C contains 20-30% ethylene oxide by mass and has a molecular weight of 3500-4500; the fatty alcohol polyether C is esterified with stearate at a temperature of 140-170°C and an esterification time of 6-10 hours.
[0013] Compared with existing technologies, the present invention has the following beneficial effects: The modified bio-based polyether defoamer prepared by the method of the present invention has good defoaming and foam-suppressing effects in both aqueous and oil-based systems, good miscibility with silicone paste, and stable storage without stratification. The defoamer prepared by the present invention can be used alone or in combination with silicone paste, has no effect on fermentation strains, is environmentally friendly, and has excellent defoaming and foam-suppressing performance. It can be used for defoaming in aqueous systems and also in anhydrous defoaming applications, such as oil-based coatings and rubber resins. Detailed Implementation
[0014] The present invention will be further described below with reference to embodiments, but these embodiments do not limit the implementation of the present invention.
[0015] Example 1: Modified bio-based polyether defoamer 1 Modified bio-based polyether defoamer 1 was prepared using the following method: 2500g of castor oil polyether polyol A1, 284g of stearic acid, 8.5g of p-toluenesulfonic acid, and 2.8g of hypophosphoric acid were added to a reactor. After purging the reactor with nitrogen, a vacuum was drawn to a degree of -0.095 MPa, and the temperature was raised to 150℃. An esterification reaction was carried out at 150℃ for 10 hours to obtain modified castor oil polyether A1. Castor oil polyether polyol A1 is prepared by addition polymerization using castor oil as an initiator. It is a propylene oxide-ethylene oxide non-regressed copolymer ether with a mass percentage of 10% ethylene oxide and a number average molecular weight of 2500.
[0016] 1500g of glucose polyether polyol B1, 284g of stearic acid, 5.3g of p-toluenesulfonic acid, and 1.8g of hypophosphoric acid were added to a reactor. After purging the reactor with nitrogen, a vacuum was drawn to a degree of -0.095 MPa, and the temperature was raised to 150℃. An esterification reaction was carried out at 150℃ for 10 hours to obtain modified glucose polyether B1. Glucose polyether polyol B1 is prepared by addition polymerization using glucose as an initiator, and is a propylene oxide-ethylene oxide non-regressed copolymer ether with a mass percentage of 10% ethylene oxide and a number average molecular weight of 1500.
[0017] 3500g of fatty alcohol polyether C1, 284g of stearic acid, 11.5g of p-toluenesulfonic acid, and 3.8g of hypophosphoric acid were added to a reactor. After purging the reactor with nitrogen, a vacuum was drawn to a vacuum degree of -0.095 MPa, and the temperature was raised to 150℃. An esterification reaction was carried out at 150℃ for 10 hours to obtain modified fatty alcohol polyether C1. Fatty alcohol polyether C1 was prepared by addition polymerization using a mixture of 1618 alcohol (C16 alcohol to C18 alcohol mass ratio of 3:7, produced by Sinarmas, Indonesia) and lactic acid in a molar ratio of 1:1.2 as initiators. It is a propylene oxide and ethylene oxide non-regressed copolymer ether with a 25% ethylene oxide mass percentage and a number average molecular weight of 3500.
[0018] Mix 60g of modified castor oil polyether A1, 30g of modified glucose polyether B1 and 10g of modified fatty alcohol polyether C1, and stir evenly to obtain modified bio-based polyether type defoamer 1.
[0019] Example 2: Modified bio-based polyether defoamer 2 Modified bio-based polyether defoamer 2 was prepared using the following method: 3000g of castor oil polyether polyol A2, 312g of stearic acid, 10g of p-toluenesulfonic acid, and 3.3g of hypophosphoric acid were added to a reactor. After purging the reactor with nitrogen, a vacuum was drawn to a degree of -0.095 MPa, and the temperature was raised to 160℃. An esterification reaction was carried out at 160℃ for 8 hours to obtain modified castor oil polyether A2. Castor oil polyether polyol A2 is prepared by addition polymerization using castor oil as an initiator. It is a propylene oxide-ethylene oxide non-regressed copolymer ether with a mass percentage of 15% ethylene oxide and a number average molecular weight of 3000.
[0020] 2000g of glucose polyether polyol B2, 312g of stearic acid, 6.9g of p-toluenesulfonic acid, and 2.3g of hypophosphoric acid were added to a reactor. After purging the reactor with nitrogen, a vacuum was drawn to a degree of -0.095 MPa, and the temperature was raised to 160℃. An esterification reaction was carried out at 160℃ for 8 hours to obtain modified glucose polyether B2. Glucose polyether polyol B2 is prepared by addition polymerization using glucose as an initiator. It is a propylene oxide-ethylene oxide non-regressed copolymer ether with a mass percentage of 10% ethylene oxide and a number average molecular weight of 2000.
[0021] 4000g of fatty alcohol polyether C2, 284g of stearic acid, 13g of p-toluenesulfonic acid, and 4.3g of hypophosphoric acid were added to a reactor. After purging the reactor with nitrogen, a vacuum was drawn to a degree of -0.095 MPa, and the temperature was raised to 160℃. An esterification reaction was carried out at 160℃ for 8 hours to obtain modified fatty alcohol polyether C2. Fatty alcohol polyether C2 was prepared by addition polymerization using a mixture of 1618 alcohol (C16 alcohol to C18 alcohol mass ratio of 3:7, produced by Sinarmas, Indonesia) and lactic acid in a molar ratio of 1:1.5 as the initiator. It is a propylene oxide-ethylene oxide non-regressed copolymer ether with a ethylene oxide mass percentage of 25% and a number average molecular weight of 4000.
[0022] Mix 65g of modified castor oil polyether A2, 20g of modified glucose polyether B2 and 15g of modified fatty alcohol polyether C2, and stir evenly to obtain modified bio-based polyether type defoamer 2.
[0023] Example 3: Modified bio-based polyether defoamer 3 Modified bio-based polyether defoamer 3 was prepared using the following method: 3500g of castor oil polyether polyol A3, 341g of stearic acid, 11.5g of p-toluenesulfonic acid, and 3.8g of hypophosphoric acid were added to a reactor. After purging the reactor with nitrogen, a vacuum was drawn to a degree of -0.095 MPa, and the temperature was raised to 170℃. An esterification reaction was carried out at 170℃ for 6 hours to obtain modified castor oil polyether A3. Castor oil polyether polyol A3 is prepared by addition polymerization using castor oil as an initiator. It is a propylene oxide and ethylene oxide non-regressed copolymer ether with a mass percentage of 15% ethylene oxide and a number average molecular weight of 3500.
[0024] 2500g of glucose polyether polyol B3, 341g of stearic acid, 8.5g of p-toluenesulfonic acid, and 2.8g of hypophosphoric acid were added to a reactor. After purging the reactor with nitrogen, a vacuum was drawn to a degree of -0.095 MPa, and the temperature was raised to 170℃. An esterification reaction was carried out at 170℃ for 6 hours to obtain modified glucose polyether B3. Glucose polyether polyol B3 is prepared by addition polymerization using glucose as an initiator, and is a propylene oxide-ethylene oxide non-regressed copolymer ether with a mass percentage of 10% ethylene oxide and a number average molecular weight of 2500.
[0025] 4500g of fatty alcohol polyether C3, 284g of stearic acid, 14.5g of p-toluenesulfonic acid, and 4.8g of hypophosphoric acid were added to a reactor. After purging the reactor with nitrogen, a vacuum was drawn to a vacuum degree of -0.095 MPa, and the temperature was raised to 170℃. An esterification reaction was carried out at 170℃ for 6 hours to obtain modified fatty alcohol polyether C3. The fatty alcohol polyether C3 was prepared by addition polymerization using a mixture of 1618 alcohol (C16 alcohol to C18 alcohol mass ratio of 3:7, produced by Sinarmas, Indonesia) and lactic acid in a molar ratio of 1:2 as the initiator. It is a propylene oxide-ethylene oxide non-regressed copolymer ether with a 25% ethylene oxide mass percentage and a number average molecular weight of 4500.
[0026] Mix 70g of modified castor oil polyether A3, 20g of modified glucose polyether B3 and 10g of modified fatty alcohol polyether C3, and stir evenly to obtain modified bio-based polyether type defoamer 3.
[0027] Comparative Example 1 According to the formulation in Example 1, 60g of modified castor oil polyether A1 and 30g of modified glucose polyether B1 were mixed and stirred evenly to obtain comparative defoamer 1.
[0028] Comparative Example 2 According to the formulation in Example 1, 60g of modified castor oil polyether A1 and 10g of modified fatty alcohol polyether C1 were mixed and stirred evenly to obtain comparative defoamer 2.
[0029] Comparative Example 3 According to the formulation in Example 1, 30g of modified glucose polyether B1 and 10g of modified fatty alcohol polyether C1 were mixed and stirred evenly to obtain comparative defoamer 3.
[0030] Comparative Example 4 The preparation method of comparative defoamer 4 is as follows: 3000g of glycerol polyether polyol, 312g of stearic acid, 10g of p-toluenesulfonic acid, and 3.3g of hypophosphoric acid were added to a reactor. After purging the reactor with nitrogen, a vacuum was drawn to a vacuum degree of -0.095 MPa, and the temperature was raised to 160℃. An esterification reaction was carried out at 160℃ for 8 hours to obtain comparative defoamer 4. The glycerol polyether polyol was prepared by addition polymerization using glycerol as an initiator. It is a propylene oxide-ethylene oxide non-regressed copolymer ether with a 15% ethylene oxide mass percentage and a number average molecular weight of 3000.
[0031] Comparative Example 5 Commercially available conventional glycerol polyether defoamer ZS-2802X: purchased from Jiangsu Zhongshan New Materials Co., Ltd., is a glycerol polyether polyol, obtained by addition polymerization with glycerol as the initiator. It is an ethylene oxide-propylene oxide copolymer with a mass percentage of 15% ethylene oxide and a number average molecular weight of 3000.
[0032] Example 4 Performance Comparison Test The defoamers prepared in Examples 1-3 and Comparative Examples 1-5 were subjected to the following performance tests.
[0033] 1. Defoaming performance test To prepare the standard foaming solution, weigh 0.25g of nonylphenol polyoxyethylene ether (NP-10, obtained by polymerizing 1mol of nonylphenol with 10mol of ethylene oxide) and 0.25g of sodium dodecylbenzenesulfonate aqueous solution with a mass percentage of 30% and add them to 50mL of water. Mix and stir until a uniform and transparent liquid is obtained. Dilute with water to 100mL to obtain the standard foaming solution.
[0034] Water-based defoamer dilution solution: Add 1g of defoamer to 19g of distilled water at 20℃ and stir well.
[0035] Oily system defoamer dilution solution: Take 1g of defoamer and add it to 99g of 92-octane gasoline, and stir well.
[0036] Defoaming and foam suppression effects in oily systems: 1L of gasoline was added to a 2L gasoline tank, followed by 1g of the diluted defoamer solution. The mixture was thoroughly mixed. Using a DGP-Z-20X rotary piston filling machine (purchased from Jiangsu Tom Intelligent Equipment Co., Ltd.), the filling speed was 1000mL / min. Each filling was set to 100mL, and 100mL of gasoline was injected into a 250mL graduated cylinder. The maximum height reached by the gasoline was recorded during injection. Each sample was measured three times, and the average of the maximum heights was taken. The average maximum height minus 100mL was the overflow foam height. The solution in the graduated cylinder was then placed in a vertical reciprocating shaker, with an oscillation frequency of 50 times / min. After oscillation for 1 minute, the above operation was repeated. The total number of oscillations accumulated until the foam decreased to below 3mL was defined as the foam suppression count.
[0037] Defoaming and foam suppression effects in aqueous systems: 100 mL of standard foaming solution was slowly poured into a 500 mL graduated cylinder along the cylinder wall. The graduated cylinder was placed in a shaker and shaken at a frequency of 300 times / min. Shaking was stopped when the foam height reached the 400 mL mark. 0.1 mL of defoamer was added, and the time required for the foam to disappear (foam height less than 3 mL) was recorded using a stopwatch; this is the defoaming time. The graduated cylinder (including the internal solution) after the defoaming test was completed was then repositioned in the same shaker and shaken at a frequency of 100 times / min for 1 minute. Timing was started, and timing was stopped when the foam height decreased to <10 mL; this recorded time is the foam suppression time. The above foam suppression effect testing steps were repeated. After each test, the solution in the graduated cylinder was allowed to stand for 5 minutes to restore its initial state. The number of shakes corresponding to a foam suppression time <0.5 min was recorded; this number is the foam suppression count.
[0038] Storage stability when mixed with silicone paste Silicone paste was prepared using conventional methods with dimethyl silicone oil and silica in a mass ratio of 100:10. 80g of silicone paste was taken, and 20g of each defoamer was added. After shearing for 10 minutes, it was found to be uniform and without stratification. After storage at 25℃ for 60 days, the stratification was tested. The stratification was classified as uniform without stratification, slight stratification, stratification, and obvious stratification.
[0039] Biodegradability analysis The biodegradability analysis method shall be in accordance with GB / T21856-2008 "Test for rapid biodegradability of chemicals and carbon dioxide generation".
[0040] Table 1. Defoaming and foam-suppressing effects of various defoamers in aqueous systems.
[0041] Table 2. Defoaming and foam-suppressing effects of various defoamers in oily systems.
[0042] As can be seen from Tables 1-2, compared with Comparative Examples 1-5, the defoamers prepared in Examples 1-3 show significant improvements in defoaming time and number of foam suppressions in aqueous systems, and in overflow foam height and number of foam suppressions in oily systems. They have good defoaming and foam suppression effects and can be widely used in the field of aqueous fermentation, as well as in the field of anhydrous defoaming of oily foams, oily coatings, and rubber resins. The bio-based modified polyether prepared in this invention has good storage stability when used in combination with silicone paste. The modified polyether defoamer prepared in this invention uses bio-based raw materials, which degrade quickly and are environmentally friendly.
Claims
1. A method for preparing a modified bio-based polyether defoamer, characterized in that: The product is prepared by uniformly mixing the following components according to their mass parts: 55-75 parts by mass of modified castor oil polyether A, 18-32 parts by mass of modified glucose polyether B, and 4-16 parts by mass of modified fatty alcohol polyether C.
2. The preparation method according to claim 1, characterized in that: The modified castor oil polyether A is prepared by the following method: castor oil is used as an initiator to randomly copolymerize with ethylene oxide and propylene oxide to obtain castor oil polyether polyol A; using p-toluenesulfonic acid and hypophosphoric acid as catalysts, the castor oil polyether polyol A is esterified with stearic acid at a molar ratio of 1:1-1.6 to obtain modified castor oil polyether A.
3. The preparation method according to claim 1 or 2, characterized in that: The castor oil polyether polyol A contains 10-20% ethylene oxide by mass and has a molecular weight of 2500-3500; the esterification temperature of castor oil polyether polyol A with stearate is 140-170℃ and the esterification time is 6-10h.
4. The preparation method according to claim 3, characterized in that: The modified glucose polyether B is prepared by the following method: glucose is used as an initiator to randomly copolymerize with ethylene oxide and propylene oxide to obtain glucose polyether polyol B; p-toluenesulfonic acid and hypophosphoric acid are used as catalysts to esterify glucose polyether polyol B with stearic acid at a molar ratio of 1:1-1:2 to obtain modified glucose polyether B.
5. The preparation method according to claim 4, characterized in that: The glucose polyether polyol B contains 10-15% ethylene oxide by mass and has a molecular weight of 1500-2500; the esterification temperature of glucose polyether polyol B with stearic acid is 140-170℃ and the esterification time is 6-10h.
6. The preparation method according to claim 5, characterized in that: The modified fatty alcohol polyether C is prepared by the following method: 1618 alcohol and lactic acid in a molar ratio of 1:1.2-2 are used as initiators and randomly copolymerized with ethylene oxide and propylene oxide to obtain fatty alcohol polyether C; p-toluenesulfonic acid and hypophosphoric acid are used as catalysts, and fatty alcohol polyether C is esterified with stearic acid in a molar ratio of 1:0.9-1.1 to obtain modified fatty alcohol polyether C.
7. The preparation method according to claim 6, characterized in that: The fatty alcohol polyether C contains 20-30% ethylene oxide by mass and has a molecular weight of 3500-4500; the fatty alcohol polyether C is esterified with stearate at a temperature of 140-170℃ and an esterification time of 6-10h.