Synthesis method of bis-diglycerol polyacyl adipate-2

Abstract

The invention relates to the technical field of organic synthesis, and particularly discloses a synthesis method of bis-diglycerol polyacyl adipate-2, which comprises the following synthesis steps: S1, stirring and mixing isostearic acid, caprylic capric acid, stearic acid and 12-hydroxystearic acid to obtain total fatty acid; s2, stirring and mixing dipolyglycerol, adipic acid, total fatty acid and an organic tin catalyst, and starting to heat; s3, the initial reaction temperature is controlled to be 140-150 DEG C, the reaction vacuum degree is 0.04 MPa, the heating rate is controlled to be 2-10 DEG C / h in the reaction process, the temperature is increased to 190-210 DEG C, then the reaction vacuum degree is converted into 0.1 MPa, and the heat preservation reaction is conducted for 4-10 h; after the reaction is completed, sampling and measuring an acid value; and S4, after the acid value reaches the standard, carrying out heat preservation reaction for 2-5 hours under a high-vacuum condition, cooling, and filtering to obtain the product. The organic tin catalyst is used, the esterification period is shortened, the conversion rate is increased, and the production cost is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of organic synthesis, and in particular to a method for synthesizing bis-diglycerol polyacyl adipate-2. Background Art

[0002] Bis-diglyceryl polyacyladipate-2 is a plant-derived emulsifier that is a light yellow ointment-like solid. It is odorless or has a slight characteristic odor. It has good adhesion, durability and water retention properties, and its water absorption capacity is over 170%.

[0003] In skincare products, baby creams, lipsticks, and other cosmetic cosmetics, Bis-Diglyceryl Polyacyladipate-2 is often used as an emollient, replacing natural lanolin to lock in much-needed moisture and prevent water loss. Compared to traditional natural lanolin, products made with Bis-Diglyceryl Polyacyladipate-2 exhibit improved heat stability, a softer texture, better adhesion, and a refreshing, non-greasy feel.

[0004] However, in the traditional synthesis method of bis-diglycerol polyacyl adipate-2, acidic catalysts (such as p-toluenesulfonic acid or sulfuric acid) are often used in the esterification reaction. Acidic catalysts are prone to corrode equipment and reaction equipment, increasing the production cost and difficulty of equipment maintenance of the production process. In addition, the temperature needs to be strictly controlled during the reaction to avoid the production of by-products, which places high demands on the production process. Subsequent steps such as alkaline washing, neutralization, and water washing are also required, which not only increases the complexity of the process, but may also generate a large amount of wastewater, which is not conducive to environmental protection. Summary of the Invention

[0005] In order to solve the above-mentioned technical problems, the present application provides a method for synthesizing bis-diglycerol polyacyl adipate-2. By using an organic tin catalyst, the esterification cycle is shortened, the conversion rate is improved, and the production cost is reduced. During the reaction process, the ester product is light in color and high in quality, and no post-treatment such as neutralization alkali washing and water washing is required. Equipment corrosion is also avoided, water resources are saved, and the environment is not polluted.

[0006] The present application provides a method for synthesizing bis-diglycerol polyacyl adipate-2, which adopts the following technical solution: A method for synthesizing bis-diglycerol polyacyl adipate-2 comprises the following steps: S1. Stirring and mixing isostearic acid, caprylic decanoic acid, stearic acid, and 12-hydroxystearic acid to obtain total fatty acids; S2, stirring and mixing diglycerol, adipic acid, total fatty acids and organotin catalyst and starting to heat; S3, control the initial reaction temperature to 140-150 ° C, the reaction vacuum to 0.04 MPa, control the heating rate to 2-10 ° C / h to raise the temperature to 190-210 ° C during the reaction, then change the reaction vacuum to 0.1 MPa, and keep the reaction at this temperature for 4-10 hours; after the reaction is completed, take samples to measure the acid value; S4. After the acid value reaches the standard, start the vacuum pump unit, and keep the reaction under high vacuum for 2-5 hours to obtain a crude product of bis-diglycerol polyacyl adipate-2. The crude product of bis-diglycerol polyacyl adipate-2 is cooled and filtered to obtain bis-diglycerol polyacyl adipate-2.

[0007] By adopting the above technical solution, an organic tin catalyst is used in the synthesis of bis-diglycerol polyacyl adipate-2. Compared with the traditional synthesis method using an acidic catalyst, the corrosion of the reaction equipment by the acidic catalyst is avoided, the equipment maintenance cost and the complexity of the production process are reduced; at the same time, the synthesis step does not require steps such as alkali washing, neutralization, and water washing, which reduces the generation of wastewater and better meets environmental protection requirements; by adjusting the gradient temperature and vacuum degree, the ester product in the reaction process is light in color and high in quality, effectively reducing the generation of by-products and improving the conversion rate of the reactants; the vacuum pump unit used in step S4 can provide a high vacuum degree, ensuring that the pressure in the reaction system is stable during the insulation reaction under high vacuum, which helps to fully proceed with the reaction and improve the purity and yield of the product. In addition, the vacuum pump unit has the characteristics of fast pumping rate and high efficiency, which can shorten the reaction time, improve production efficiency, and reduce production costs.

[0008] Optionally, the added amount of the organotin catalyst is 0.1-1% of the total mass of diglycerol, adipic acid and total fatty acids.

[0009] By adopting the above technical solution, within the addition amount range, the organotin catalyst can ensure that the synthesis reaction proceeds efficiently and stably. An excessive amount of organotin catalyst may promote the reverse hydrolysis of the generated ester bond, resulting in an increase in the acid value, and a smaller amount of organotin catalyst leads to a slower reaction rate. An appropriate amount of organotin catalyst can control the acid value of the product within a certain range, improve the consistency and quality stability of the product, and control the cost.

[0010] Optionally, the organic tin catalyst is one or more of tetrabutyltin, dibutyltin oxide, and dibutyltin dilaurate.

[0011] By adopting the above technical solution, these organotin catalysts have good catalytic activity and selectivity, can effectively promote the esterification reaction during the reaction process, accelerate the reaction rate, and shorten the reaction time; and have good compatibility with the reaction system, will not produce other adverse reactions during the reaction process, and help to improve the quality and yield of the product.

[0012] Optionally, the molar ratio of the adipic acid to the diglycerol is 1:1.5-2.5, and the molar ratio of the diglycerol to the total fatty acids is 1:2-3.

[0013] Optionally, in the total fatty acids, the molar ratio of caprylic acid, stearic acid, isostearic acid and 12-hydroxystearic acid is 2.3-5.0:2.6-6.0:0.8-1.2:0.5-0.9.

[0014] Optionally, the criterion for the acid value to meet the standard in step S4 is that the acid value measured by sampling in step S3 is less than 6.0 mgKOH / g.

[0015] Optionally, the bis-diglycerol polyacyl adipate-2 obtained in step S4 has an acid value of 0-2.0 mgKOH / g, a hydroxyl value of 55-85 mgKOH / g, and a saponification value of 270-290 mgKOH / g.

[0016] By adopting the above technical solution, clear quantitative indicators are provided for the obtained bis-diglycerol polyacyl adipate-2, ensuring quality stability and guaranteeing the performance and effect of the product in practical applications.

[0017] In summary, this application includes at least one of the following beneficial technical effects: 1. This application uses an organotin catalyst instead of the existing acidic catalyst, avoiding corrosion of the reaction equipment by the acidic catalyst, reducing equipment maintenance costs and the complexity of the production process. Furthermore, this synthesis step does not require alkaline neutralization and water washing, reducing wastewater generation and better meeting environmental protection requirements. 2. In the synthesis process of the present application, by adjusting the temperature gradient and the vacuum degree, the ester product is light in color and high in quality during the reaction, which effectively reduces the generation of by-products and improves the conversion rate of the reactants. DETAILED DESCRIPTION

[0018] The present application is further described in detail below with reference to the following examples and comparative examples.

[0019] If no specific experimental steps or conditions are specified in the examples, the experiments can be carried out according to the conventional experimental steps or conditions described in the literature in this field; if the manufacturers of the reagents or instruments are not specified, they are all conventional reagent products that can be obtained commercially.

[0020] Performance Testing Acid value: obtained according to the test method in GB / T 5009.229-2016; Hydroxyl value: obtained according to the test method in SN / T 0801.20-1999; Saponification value: obtained according to the test method in GB / T 5534-2024.

[0021] Example 1 A method for synthesizing bis-diglycerol polyacyl adipate-2 comprises the following steps: S1. 283.9 g, 607.2 g, 173.5 g, and 128.3 g of octanoic acid, stearic acid, isostearic acid, and 12-hydroxystearic acid, respectively, were heated to a molten state in a molar ratio of 3.0:3.5:1.0:0.7, and then stirred to form total fatty acids; S2. Stir and mix 332.3 g (2.0 mol) of diglycerol, 146.1 g (1.0 mol) of adipic acid, 1192.8 g (5.0 mol) of total fatty acids, and 8.4 g of tetrabutyltin, and begin heating. S3, control the initial reaction temperature to 140 ° C, the reaction vacuum to 0.04 MPa, control the heating rate to 6 ° C / h to 200 ° C during the reaction, and then change the reaction vacuum to 0.1 MPa, and keep the reaction for 6 hours; after the reaction is completed, take a sample to measure the acid value, which is 2.5 mgKOH / g; S4. Turn on the vacuum pump unit and keep the reaction under high vacuum for 3 hours to obtain a crude product. After cooling and filtering the crude product, bis-diglycerol polyacyl adipate-2 is obtained; the conversion rate of bis-diglycerol polyacyl adipate-2 is 98.2%.

[0022] The indicators of bis-diglycerol polyacyladipate-2 are: white to light yellow paste solid at 20°C, odorless or with a slight characteristic odor at 20°C, acid value of 0.10 mgKOH / g, hydroxyl value of 73 mgKOH / g, and saponification value of 281 mgKOH / g.

[0023] Example 2 A method for synthesizing bis-diglycerol polyacyl adipate-2, which differs from Example 1 in that the amount of organotin catalyst added is different, using 1.7 g of tetrabutyltin, and all other conditions are the same as Example 1; The acid value of the sample taken after the reaction in step S3 was 4.5 mgKOH / g was measured; and the conversion rate of bis-diglycerol polyacyl adipate-2 in step S4 was 91.3%.

[0024] The indicators of bis-diglycerol polyacyladipate-2 are: white to light yellow paste solid at 20°C, odorless or with a slight characteristic odor at 20°C, acid value of 1.2 mgKOH / g, hydroxyl value of 75 mgKOH / g, and saponification value of 276 mgKOH / g.

[0025] Example 3 A method for synthesizing bis-diglycerol polyacyl adipate-2, which differs from Example 1 in that the amount of organotin catalyst added is different, using 16.7 g of tetrabutyltin, and all other conditions are the same as Example 1; In which, after the reaction in step S3 is completed, the acid value of the sample is measured to be 3.2 mgKOH / g; and in step S4, the conversion rate of bis-diglycerol polyacyl adipate-2 is 96.5%.

[0026] The indicators of bis-diglycerol polyacyladipate-2 are as follows: white to light yellow paste solid at 20°C, odorless or with a slight characteristic odor at 20°C, acid value of 1.6 mgKOH / g, hydroxyl value of 71 mgKOH / g, and saponification value of 280 mgKOH / g.

[0027] Comparative Example 1 A method for synthesizing bis-diglycerol polyacyl adipate-2, which differs from Example 1 in that the amount of organic tin catalyst added is different, using 25.1 g of tetrabutyltin, and all other conditions are the same as Example 1; The acid value of the sample taken after the reaction in step S3 was 3.8 mgKOH / g was measured; and the conversion rate of bis-diglycerol polyacyl adipate-2 in step S4 was 92.8%.

[0028] The indicators of bis-diglycerol polyacyladipate-2 are: white to light yellow paste solid at 20°C, odorless or with a slight characteristic odor at 20°C, acid value of 2.5 mgKOH / g, hydroxyl value of 65 mgKOH / g, and saponification value of 283 mgKOH / g.

[0029] Compared with Comparative Example 1, in Examples 1-3, when the amount of organotin catalyst added was 1.5% of the total mass of diglycerol, adipic acid, and total fatty acids, the acid value increased abnormally. This may be due to the fact that the excess organotin catalyst promoted the reverse hydrolysis of the formed ester bonds. When the amount of organotin catalyst added was 0.1%-1.0% of the total mass of diglycerol, adipic acid, and total fatty acids, the organotin catalyst ensured that the synthesis reaction proceeded efficiently and stably. The final product met the requirements, had good product consistency and quality stability, and was cost-effective.

[0030] Example 4 A method for synthesizing bis-diglycerol polyacyl adipate-2, which differs from Example 1 in that the type of organotin catalyst is different, and an equal amount of dibutyltin dilaurate is used instead of tetrabutyltin. All other conditions are the same as those in Example 1. In which, after the reaction in step S3 is completed, the acid value of the sample is measured to be 2.1 mgKOH / g; and in step S4, the conversion rate of bis-diglycerol polyacyl adipate-2 is 97.6%.

[0031] The indicators of bis-diglycerol polyacyladipate-2 are: white to light yellow paste solid at 20°C, odorless or with a slight characteristic odor at 20°C, acid value of 0.12 mgKOH / g, hydroxyl value of 72 mgKOH / g, and saponification value of 279 mgKOH / g.

[0032] Example 5 A method for synthesizing bis-diglycerol polyacyl adipate-2, which differs from Example 1 in that the type of organotin catalyst is different, and equal amounts of dibutyltin oxide and dibutyltin dilaurate are used instead of tetrabutyltin, wherein the mass ratio of dibutyltin oxide to dibutyltin dilaurate is 1:1. All other conditions are the same as in Example 1; In which, after the reaction in step S3 is completed, the acid value of the sample is measured to be 1.5 mgKOH / g; and in step S4, the conversion rate of bis-diglycerol polyacyl adipate-2 is 98.0%.

[0033] The indicators of bis-diglycerol polyacyladipate-2 are: white to light yellow paste solid at 20°C, odorless or with a slight characteristic odor at 20°C, acid value of 0.05 mgKOH / g, hydroxyl value of 75 mgKOH / g, and saponification value of 278 mgKOH / g.

[0034] Comparative Example 2 A method for synthesizing bis-diglycerol polyacyl adipate-2, which differs from Example 1 in that an equal amount of p-toluenesulfonic acid is used instead of tetrabutyltin, and all other aspects are the same as Example 1; In which, after the reaction in step S3 is completed, the acid value of the sample is measured to be 6.0 mgKOH / g; and in step S4, the conversion rate of bis-diglycerol polyacyl adipate-2 is 75.0%.

[0035] The indicators of bis-diglycerol polyacyladipate-2 are: light yellow to yellow paste solid at 20°C, odorless or with a slight characteristic odor at 20°C, acid value of 0.28 mgKOH / g, hydroxyl value of 76 mgKOH / g, and saponification value of 274 mgKOH / g.

[0036] Compared with Example 1, in Comparative Example 2, under the same reaction conditions and catalyst dosage, after using an acidic catalyst and at the same reaction time, the conversion rate of bis-diglycerol polyacyl adipate-2 was only 75%, and the color of the product became darker; thus, in the synthesis process of bis-diglycerol polyacyl adipate-2, the use of an organotin catalyst not only saves reaction time, but also improves the conversion rate and product quality of bis-diglycerol polyacyl adipate-2.

[0037] Example 6 A method for synthesizing bis-diglycerol polyacyl adipate-2 comprises the following steps: S1. 189.3 g, 416.3 g, 55.5 g, and 36.7 g of octanoic acid, stearic acid, isostearic acid, and 12-hydroxystearic acid, respectively, in a molar ratio of 5.0:6.0:0.8:0.5, are heated to a molten state, and then stirred to form total fatty acids; S2. Stir and mix 249.3 g (1.5 mol) of diglycerol, 146.1 g (1.0 mol) of adipic acid, 697.8 g (3.0 mol) of total fatty acids, and 5.5 g of tetrabutyltin and begin heating. S3, control the initial reaction temperature to 140 ° C, the reaction vacuum to 0.04 MPa, control the heating rate to 6 ° C / h to 200 ° C during the reaction, and then change the reaction vacuum to 0.1 MPa, and keep the reaction for 6 hours; after the reaction is completed, take a sample to measure the acid value, which is 1.6 mgKOH / g; S4. Turn on the vacuum pump unit and carry out the reaction under high vacuum for 3 hours to obtain a crude product. The crude product is cooled and filtered to obtain bis-diglycerol polyacyl adipate-2; the conversion rate of bis-diglycerol polyacyl adipate-2 is 97.3%.

[0038] The indicators of bis-diglycerol polyacyladipate-2 are: white to light yellow paste solid at 20°C, odorless or with a slight characteristic odor at 20°C, acid value of 0.08 mgKOH / g, hydroxyl value of 76 mgKOH / g, and saponification value of 275 mgKOH / g.

[0039] Example 7 A method for synthesizing bis-diglycerol polyacyl adipate-2 comprises the following steps: S1. 388.0 g, 804.0 g, 371.1 g, and 261.3 g of octanoic acid, stearic acid, isostearic acid, and 12-hydroxystearic acid, respectively, in a molar ratio of 2.3:2.6:1.2:0.8, are heated to a molten state, and then stirred to form total fatty acids; S2. Stir and mix 415.4 g (2.5 mol) of diglycerol, 146.1 g (1.0 mol) of adipic acid, 1824.4 g (7.5 mol) of total fatty acids, and 11.9 g of tetrabutyltin and begin heating. S3, control the initial reaction temperature to 140 ° C, the reaction vacuum to 0.04 MPa, control the heating rate to 6 ° C / h to 200 ° C during the reaction, and then change the reaction vacuum to 0.1 MPa, and keep the reaction for 6 hours; after the reaction is completed, take a sample to measure the acid value, which is 3.8 mgKOH / g; S4. Turn on the vacuum pump unit and carry out the reaction under high vacuum for 3 hours to obtain a crude product. The crude product is cooled and filtered to obtain bis-diglycerol polyacyl adipate-2; the conversion rate of bis-diglycerol polyacyl adipate-2 is 97.5%.

[0040] The indicators of bis-diglycerol polyacyladipate-2 are: white to light yellow paste solid at 20°C, odorless or with a slight characteristic odor at 20°C, acid value of 0.15 mgKOH / g, hydroxyl value of 69 mgKOH / g, and saponification value of 285 mgKOH / g.

[0041] Example 8 A method for synthesizing bis-diglycerol polyacyl adipate-2 comprises the following steps: S1 is the same as S1 in Example 1; S2, the same as S2 in Example 1; S3, control the initial reaction temperature to 140 ° C, the reaction vacuum to 0.04 MPa, control the heating rate to 2 ° C / h to 190 ° C during the reaction, and then change the reaction vacuum to 0.1 MPa, and keep the reaction for 4 hours; after the reaction is completed, take a sample to measure the acid value, which is 3.7 mgKOH / g; S4. Turn on the vacuum pump unit and carry out the reaction under high vacuum for 5 hours to obtain a crude product. The crude product is cooled and filtered to obtain bis-diglycerol polyacyl adipate-2; the conversion rate of bis-diglycerol polyacyl adipate-2 is 97.2%.

[0042] The indicators of bis-diglycerol polyacyladipate-2 are: white to light yellow paste solid at 20°C, odorless or with a slight characteristic odor at 20°C, acid value of 0.8 mgKOH / g, hydroxyl value of 74 mgKOH / g, and saponification value of 279 mgKOH / g.

[0043] Example 9 A method for synthesizing bis-diglycerol polyacyl adipate-2 comprises the following steps: S1 is the same as S1 in Example 1; S2, the same as S2 in Example 1; S3, control the initial reaction temperature to 150 ° C, the reaction vacuum to 0.04 MPa, control the heating rate to 10 ° C / h to 210 ° C during the reaction, and then change the reaction vacuum to 0.1 MPa, and keep the reaction for 10 hours; after the reaction is completed, take a sample to measure the acid value, which is 3.5 mgKOH / g; S4. Turn on the vacuum pump unit and carry out the reaction under high vacuum for 2 hours to obtain a crude product. The crude product is cooled and filtered to obtain bis-diglycerol polyacyl adipate-2; the conversion rate of bis-diglycerol polyacyl adipate-2 is 96.9%.

[0044] The indicators of bis-diglycerol polyacyladipate-2 are: white to light yellow paste solid at 20°C, odorless or with a slight characteristic odor at 20°C, acid value of 0.9 mgKOH / g, hydroxyl value of 71 mgKOH / g, and saponification value of 283 mgKOH / g.

[0045] The specific embodiments of this application are merely explanations of this application and are not limitations of this application. After reading this specification, those skilled in the art may make non-creative modifications to this embodiment as needed, but as long as they are within the scope of the claims of this application, they are protected by patent law.

Claims

1. A method for synthesizing bis-diglycerol polyacyl adipate-2, characterized in that: The method comprises the following synthesis steps: S1. Stirring and mixing isostearic acid, caprylic decanoic acid, stearic acid, and 12-hydroxystearic acid to obtain total fatty acids; S2, stirring and mixing diglycerol, adipic acid, total fatty acids and organotin catalyst and starting to heat; S3, control the initial reaction temperature to 140-150 ° C, the reaction vacuum to 0.04 MPa, control the heating rate to 2-10 ° C / h to raise the temperature to 190-210 ° C during the reaction, then change the reaction vacuum to 0.1 MPa, and keep the reaction at this temperature for 4-10 hours; after the reaction is completed, take samples to measure the acid value; S4. After the acid value reaches the standard, start the vacuum pump unit, and keep the reaction under high vacuum for 2-5 hours to obtain a crude product of bis-diglycerol polyacyl adipate-2. The crude product of bis-diglycerol polyacyl adipate-2 is cooled and filtered to obtain bis-diglycerol polyacyl adipate-2.

2. The method for synthesizing bis-diglycerol polyacyl adipate-2 according to claim 1, wherein: The added amount of the organotin catalyst is 0.1-1% of the total mass of diglycerol, adipic acid and total fatty acids.

3. The method for synthesizing bis-diglycerol polyacyl adipate-2 according to claim 2, wherein: The organic tin catalyst is one or more of tetrabutyltin, dibutyltin oxide and dibutyltin dilaurate.

4. The method for synthesizing bis-diglycerol polyacyl adipate-2 according to claim 1, wherein: The molar ratio of the adipic acid to the diglycerol is 1:1.5-2.5, and the molar ratio of the diglycerol to the total fatty acids is 1:2-3.

5. The method for synthesizing bis-diglycerol polyacyl adipate-2 according to claim 4, wherein: In the total fatty acids, the molar ratio of caprylic acid, stearic acid, isostearic acid and 12-hydroxystearic acid is 2.3-5.0:2.6-6.0:0.8-1.2:0.5-0.

9.

6. The method for synthesizing bis-diglycerol polyacyl adipate-2 according to claim 1, characterized in that: The standard for the acid value in step S4 to meet the standard is that the acid value measured by sampling in step S3 is less than 6.0 mgKOH / g.

7. The method for synthesizing bis-diglycerol polyacyl adipate-2 according to claim 1, characterized in that: The bis-diglycerol polyacyl adipate-2 obtained in step S4 is a white to light yellow paste solid at 20° C., odorless or with a slight characteristic odor at 20° C., and has an acid value of 0-2.0 mgKOH / g, a hydroxyl value of 55-85 mgKOH / g, and a saponification value of 270-290 mgKOH / g.