阅读说明：本技术 一种简便、低成本高亲水性聚甘油酯的制备方法 (Simple, low-cost and high-hydrophilicity polyglycerol ester preparation method ) 是由 邢鹏遥 郝爱友 安伟 于 2020-06-28 设计创作，主要内容包括：本发明涉及一种简便、低成本制备高亲水性聚甘油酯的方法,本发明的方法通过对常规聚甘油酯的接支,然后使接支链继续与聚甘油反应,使亲水基得到延长,得到亲水性强的聚甘油酯,生产过程中不使用环氧乙烷及缩水甘油,生产过程中没有产生二噁烷的隐患,对环境友好,成本低,得到的高亲水性聚甘油酯质量高,属于可降解、环境友好型产品。(The invention relates to a method for preparing high-hydrophilicity polyglycerol ester simply and conveniently at low cost, which comprises the steps of grafting conventional polyglycerol ester, continuously reacting the grafted chain with polyglycerol to prolong hydrophilic groups and obtain the polyglycerol ester with strong hydrophilicity, wherein ethylene oxide and glycidol are not used in the production process, the hidden danger of generating dioxane is avoided in the production process, the method is environment-friendly, the cost is low, and the obtained high-hydrophilicity polyglycerol ester is high in quality and belongs to a degradable and environment-friendly product.)

1. A simple, low-cost and high-hydrophilicity polyglycerol ester preparation method comprises the following steps:

1) polymerizing polyglycerol and fatty acid under the action of a catalyst to obtain polyglycerol ester;

2) quickly cooling the polyglycerol ester obtained in the step 1) to 100-110 ℃, adding succinic anhydride, preserving heat for reaction, and stopping the reaction when the acid value of the system is reduced to a theoretical acid value to obtain grafted branched polyglycerol ester;

3) adding polyglycerol into the grafted and branched polyglycerol ester, raising the temperature for reaction in stages, removing generated water in the reaction process until the acid value of a reaction system is less than or equal to 2mgKOH/g, stopping the reaction, then cooling to a temperature less than 90 ℃, and discharging to obtain the high-hydrophilicity polyglycerol ester.

2. The method according to claim 1, wherein the cooling time for rapidly cooling to 100 ℃ in step 2) is 2 to 3 hours.

3. The method according to claim 1, wherein the molar ratio of succinic anhydride to the polyglycerin in the step 2) is 0.1 to 0.5: 1.

4. The method according to claim 1, wherein the molar ratio of succinic anhydride to the polyglycerin in the step 2) is 0.3: 1.

5. The method according to claim 1, wherein the reaction time in the step 2) is 1.5 to 2 hours.

6. The method according to claim 1, wherein in step 3), the polyglycerol is a polyglycerol obtained by a glycerol polymerization method, preferably, the polyglycerol is one of diglycerol (hydroxyl value 1352), tetraglycerol (hydroxyl value 1071), hexaglycerol (hydroxyl value 970), decaglycerol (hydroxyl value 888); preferably, in step 3), the polyglycerol is a tetraglycerol or a hexaglycerol.

7. The method according to claim 1, wherein the ratio of the molar amount of the polyglycerol in step 3) to the molar amount of the succinic anhydride in step 2) is 0.3 to 1: 1; preferably, in step 3), the ratio of the molar amount of polyglycerol to the molar amount of succinic anhydride in step 2) is 0.6-1: 1.

8. The preparation method according to claim 1, wherein in the step 3), after the material addition is completed, nitrogen is introduced to replace air; the staged heating reaction is that the temperature is quickly raised to 200 ℃ at the heating rate of 25-35 ℃/h for reaction for 2 hours, then the temperature is continuously raised to 240 ℃ at the heating rate of 15-25 ℃/h, and the temperature reaction is kept until the system is in a homogeneous transparent state.

9. The production method according to claim 1, wherein in the step 3), the removal of the produced water is performed by vacuum distillation in a degree of vacuum of 0.04 to 0.095 MPa; and the temperature is quickly reduced to a temperature of less than 130 ℃ within 2-3 hours, ester exchange is avoided, the temperature is continuously reduced to 80 ℃, and discharging is carried out.

10. The method as claimed in claim 1, wherein the polyglycerol obtained in step 1) is a polyglycerol obtained by a glycerol polymerization method, and the polyglycerol has a hydroxyl value of 860-1360.

The technical field is as follows:

the invention relates to a simple and low-cost method for preparing high-hydrophilicity polyglycerol ester, belonging to the field of functional materials.

Background art:

the surfactant is called industrial monosodium glutamate, is indispensable in the fields of washing, chemical engineering, industrial processing and the like, and mainly comprises an anionic surfactant, a cationic surfactant, an amphoteric surfactant and a nonionic surfactant. Among them, Polyoxyethylene Ether (PEG) surfactants are the most widely used nonionic surfactants, and mainly include alkylphenol ethoxylates (APEO), fatty alcohol-polyoxyethylene ether (AEO), fatty acid-polyoxyethylene ether (AE), and the like. Among them, the polyoxyethylene group as the hydrophilic group is obtained by polymerizing ethylene oxide derived from petrochemical sources. Therefore, Polyoxyethylene Ether (PEG) surfactants may be accompanied by production of carcinogen dioxane in the production process, and after the surfactants are used, the surfactants are not easily degraded, and easily enter the natural environment and enter the ecological circulation system, so that potential risks are generated. Furthermore, ethylene oxide is a hazardous raw material and great care must be taken during manufacture to minimize the risk to the operator. With the concept of sustainable development becoming increasingly more attentive, this material will gradually lose its appeal.

Therefore, surfactants derived from renewable raw materials have been the subject of research, among which polyglycerol esters derived from glycerol and fatty acids of vegetable origin are among the most promising ones. Glycerol is polymerized by itself to give polyglycerol which reacts with fatty acids of different chain lengths in different proportions to give polyglycerol esters of HLB 2-16. The polyglycerol ester is prepared from renewable raw materials, has high safety, is used as an emulsifier, a stabilizer and a defoaming agent, and is widely applied to the industries of food, cosmetics, daily chemicals and the like.

The reason for limiting the wide range of applications of polyglyceryl esters is that highly hydrophilic polyglyceryl esters are difficult to prepare by a simple process: because glycerol has three hydroxyl structures, a plurality of reaction sites, easy cyclization and the like in the polymerization process, long-chain polyglycerol is difficult to obtain by adopting a conventional polymerization method, and then high-hydrophilic polyglycerol fatty acid ester is difficult to obtain.

Patent document CN 1308276C analyzed, by LC/MS analysis, decaglycerol #750, which is a mixture of diglycerol to tetradecylglycerol and contains a large amount of cyclic structures, and which is sold by Kwakayasu pharmaceutical Co. Polyglycerol was prepared by the following method: the glycerol was heated to 120 ℃ and then glycidol and phosphoric acid were gradually added dropwise, and the reaction was continued until the concentration of glycidol was less than 0.1%. The resulting product has very little ring structure. However, in the reaction process, the glycidol used is not suitable for preparation and storage, and the production cost is much higher than that of the traditional process.

Similarly, in JPH 08109153, a method for producing a polyglycerol ester by polymerizing a fatty acid with glycidol, and in JP2007077405A, example 1 discloses that a polyglycerol ester having a degree of monoester substitution as high as 87.7% can be obtained by adding glycidyl ether dropwise to a fatty acid at 140 ℃ under the catalysis of phosphoric acid. The two methods use glycidol in the preparation process, and have the same problem.

It can be seen from the existing reports that the polyglycerol product obtained by the traditional base catalysis process has lower polymerization degree, more cyclic structures, and more serious problems of smell, color and the like. Although it is possible to produce polyglycerol having a small cyclic structure or polyglycerol ester having a high monoester content from glycidyl ether, the production of the glycidyl raw material itself is difficult, the source is limited, and the production cost is high. In addition, glycidol itself is a highly toxic substance.

Therefore, the research and development of a novel preparation process of the high-hydrophilicity polyglycerol ester has important significance, and is beneficial to promoting the development of the polyglycerol ester as an emulsifier, a stabilizer and a dispersant in the industries of cosmetics, foods, daily chemicals and the like.

The invention content is as follows:

aiming at the defects of the prior art, the invention provides a method for preparing the high-hydrophilicity polyglycerol ester simply and conveniently at low cost.

According to the method, the conventional polyglycerol ester is grafted, and then the grafted chain continuously reacts with the polyglycerol, so that hydrophilic groups are prolonged, the polyglycerol ester with strong hydrophilicity is obtained, ethylene oxide and glycidol are not used in the whole production process, the hidden danger of generating dioxane is avoided, the method is environment-friendly, the cost is low, the obtained high-hydrophilicity polyglycerol ester is high in quality, and the method belongs to a degradable and environment-friendly product.

Description of terms:

theoretical acid number is the acid number/2 of the polyglycerol ester and succinic anhydride blend at the time of feed.

The invention is realized by the following technical scheme:

a simple, low-cost and high-hydrophilicity polyglycerol ester preparation method comprises the following steps:

1) polymerizing polyglycerol and fatty acid under the action of a catalyst to obtain polyglycerol ester;

2) quickly cooling the polyglycerol ester obtained in the step 1) to 100-110 ℃, adding succinic anhydride, preserving heat for reaction, and stopping the reaction when the acid value of the system is reduced to a theoretical acid value to obtain grafted branched polyglycerol ester;

3) adding polyglycerol into the grafted and branched polyglycerol ester, raising the temperature for reaction in stages, removing generated water in the reaction process until the acid value of a reaction system is less than or equal to 2mgKOH/g, stopping the reaction, then cooling to a temperature less than 90 ℃, and discharging to obtain the high-hydrophilicity polyglycerol ester.

The 10% aqueous solution of the polyglycerol ester obtained by the invention is completely transparent, can keep no phenomena of turbidity, precipitation and the like in one month, and has high hydrophilicity and high stability.

Preferably, in step 2), the cooling time for rapidly cooling to 100 ℃ is 2 to 3 hours.

According to the invention, the molar ratio of succinic anhydride to polyglycerol in step 2) is preferably 0.1 to 0.5:1, and the molar ratio of succinic anhydride to polyglycerol in step 2) is preferably 0.3: 1.

Preferably, according to the invention, in step 2), the reaction time is from 1.5 to 2 hours.

Preferably, in step 3), the polyglycerol is polyglycerol obtained by glycerol polymerization, and preferably, the polyglycerol is one of diglycerol (hydroxyl value of 1352), tetraglycerol (hydroxyl value of 1071), hexaglycerol (hydroxyl value of 970) and decaglycerol (hydroxyl value of 888).

Preferably, in step 3) according to the present invention, the polyglycerol is a tetraglycerol or a hexaglycerol.

Preferably, according to the invention, the ratio of the molar amount of polyglycerol in step 3) to the molar amount of succinic anhydride in step 2) is 0.3 to 1: 1.

Preferably, in step 3), the ratio of the molar amount of polyglycerol to the molar amount of succinic anhydride in step 2) is 0.6-1: 1.

Preferably, in step 3), after the material addition is completed, nitrogen is introduced to replace air.

Preferably, in step 3), the temperature is raised to 200 ℃ rapidly at a rate of 25-35 ℃/h for 2 hours, and then raised to 240 ℃ at a rate of 15-25 ℃/h, and the temperature is kept for reaction until the system is in a homogeneous transparent state.

Preferably, in step 3), the removal of the generated water is carried out by means of reduced pressure distillation under a vacuum of 0.04 to 0.095 MPa.

Preferably, in the step 3), the temperature is rapidly reduced to a temperature of less than 130 ℃ within 2-3 hours, so as to avoid ester exchange, and the temperature is continuously reduced to 80 ℃, and discharging is performed.

Preferably, in step 1), the polyglycerol is a polyglycerol obtained by a glycerol polymerization method, and the hydroxyl value of the polyglycerol is 860-1360.

The glycerol polymerization process is currently conventional.

Preferably, the polyglycerol is one of diglycerol (hydroxyl value 1352), tetraglycerol (hydroxyl value 1071), hexaglycerol (hydroxyl value 970) and decaglycerol (hydroxyl value 888).

Preferably, according to the invention, the polyglycerol is a hexaglycerol or decaglycerol.

Preferably, in step 1), the fatty acid is one or more of capric acid, lauric acid, myristic acid and oleic acid.

Preferably, according to the invention, in step 1), the fatty acid is lauric acid or oleic acid.

Preferably, in step 1), the polymerization temperature is 190 ℃ to 210 ℃, the reaction time is 2 hours, and when the acid value is less than or equal to 2mgKOH/g, the reaction is completed to obtain the conventional polyglycerol ester. The water formed during the reaction was removed by distillation under reduced pressure.

According to the invention, in step 1), the molar ratio of the polyglycerol to the fatty acid is (1-2) to (1-2), and the catalyst is an acid or alkali esterification catalyst, and is used in an amount of 0.05-0.1% of the total mass of the reactants.

According to the invention, in the step 1), the polymerization reaction is carried out under negative pressure, the vacuum degree is 0.02-0.08 MPa, and after the reaction is finished, nitrogen is introduced to restore the system pressure to normal pressure.

The acid value of the mixture and the acid value of the reaction system were measured by a conventional method: titration method of standard solution of potassium hydroxide.

The invention has the advantages that:

1. the method of the invention carries out grafting on the conventional polyglycerol ester, and then the grafted chain continuously reacts with the polyglycerol, so that the obtained polyglycerol ester has the characteristics of high hydrophilicity, strong emulsifying and solubilizing capabilities, high product HLB (HLB is more than 13), good water solution stability and the like compared with the polyglycerol ester or polyoxyethylene ether surfactant obtained by the conventional method, belongs to degradable and environment-friendly products, and has wide application prospects in the aspects of personal care, daily chemical industry, washing and the like.

2. According to the method disclosed by the invention, ethylene oxide and glycidol are not used in the production process, the hidden danger of generating dioxane is avoided in the production process, the method is environment-friendly, the cost is low, and the obtained high-hydrophilicity polyglycerol ester is high in quality.

Description of the drawings:

FIG. 1 is a mass spectrum of the precipitate of comparative example 1.

The specific implementation mode is as follows:

the present invention is further illustrated by, but is not limited to, the following specific examples.