阅读说明：本技术 一种异辛醇聚氧乙烯醚异辛酸酯的制备方法 (Preparation method of isooctanol polyoxyethylene ether isooctoate ) 是由 刘志湘 王新荣 王马济世 万庆梅 于 2021-07-29 设计创作，主要内容包括：本发明提供一种异辛醇聚氧乙烯醚异辛酸酯的制备方法,包括以下步骤：S1、以异辛醇和环氧乙烷为原料,在聚合催化剂的作用下进行聚合反应,反应结束后用氮气鼓泡脱气1-3小时,得到异辛醇聚氧乙烯醚；S2、在烧瓶中加入反应量的异辛醇聚氧乙烯醚和异辛酸,搅拌下加入酯化催化剂,缓慢升温；S3、然后在氮气流的条件下及时分出水,过滤得到无色至微黄色透明的产品。本发明采用固体碱性催化剂进行聚合反应,在固体碱性催化剂作用下进行酯化反应,工艺简单,副反应少,能有效降低成本；制得的异辛醇聚氧乙烯醚异辛酸酯中二噁烷含量≤10ppm,具有优异的铺展性,吸收性、无刺激性。(The invention provides a preparation method of isooctanol polyoxyethylene ether isooctoate, which comprises the following steps: s1, carrying out a polymerization reaction under the action of a polymerization catalyst by using isooctyl alcohol and ethylene oxide as raw materials, and carrying out bubbling degassing for 1-3 hours by using nitrogen after the reaction is finished to obtain isooctyl alcohol polyoxyethylene ether; s2, adding reaction amount of isooctanol polyoxyethylene ether and isooctanoic acid into a flask, adding an esterification catalyst while stirring, and slowly heating; s3, timely separating out water under the condition of nitrogen flow, and filtering to obtain a colorless to yellowish transparent product. The invention adopts the solid alkaline catalyst to carry out polymerization reaction, and carries out esterification reaction under the action of the solid alkaline catalyst, so that the process is simple, the side reaction is less, and the cost can be effectively reduced; the content of dioxane in the prepared isooctanol polyoxyethylene ether isooctanoic acid ester is less than or equal to 10ppm, and the isooctanol polyoxyethylene ether isooctanoic acid ester has excellent spreadability, absorbability and no irritation.)

1. The preparation method of isooctanol polyoxyethylene ether isooctoate is characterized by comprising the following steps:

s1, carrying out a polymerization reaction under the action of a polymerization catalyst by using isooctyl alcohol and ethylene oxide as raw materials, and carrying out bubbling degassing for 1-3 hours by using nitrogen after the reaction is finished to obtain isooctyl alcohol polyoxyethylene ether;

s2, adding reaction amount of isooctanol polyoxyethylene ether and isooctanoic acid into a flask, adding an esterification catalyst while stirring, and slowly heating;

s3, timely separating out water under the condition of nitrogen flow, and filtering to obtain a colorless to yellowish transparent product.

2. The method according to claim 1, wherein the polymerization equation in S1 is:

wherein n is 3 to 10.

3. The method according to claim 1, wherein the dehydration esterification reaction equation in S2 is:

wherein n is 3 to 10.

4. The production method according to claim 1, wherein in the S1, the molar ratio of isooctyl alcohol to ethylene oxide is 1: 3-10.

5. The production method according to claim 1 or 4, wherein in the S1, the nitrogen bubbling flow rate is 5 to 10 ml/min.

6. The production method according to claim 1, wherein in the S1, the polymerization catalyst is a solid basic catalyst.

7. The production method according to claim 6, wherein the polymerization catalyst is added in an amount of 0.01 to 0.5% by weight based on the total weight of the isooctyl alcohol and ethylene oxide.

8. The method according to claim 1, wherein the molar ratio of isooctanol polyoxyethylene ether to isooctanoic acid in S2 is 1: 0.9-1.0.

9. The production method according to claim 1 or 8, wherein the esterification catalyst is a solid basic catalyst.

10. The method according to claim 9, wherein the esterification catalyst is added in an amount of 0.1 to 0.3% by weight based on the total weight of isooctanol polyoxyethylene ether and isooctanoic acid.

Technical Field

The invention belongs to the technical field of preparation of ester compounds in organic chemistry, and particularly relates to a preparation method of isooctanol polyoxyethylene ether isooctanoate.

Background

Isooctanol polyoxyethylene ether isooctanoate is a cosmetic additive, which is a derivative of polyethoxy introduced into ester bond of isooctanol isooctanoate, and the introduction of water-based group makes the polarity of the product after film forming be very small, the spreadability is better, and the detergency, wetting power and emulsifying power of the cosmetic are correspondingly improved. In addition, isooctanol polyoxyethylene ether isooctanoate is widely applied in the industries of textile printing and dyeing, leather, papermaking, paint, metal processing and the like.

At present, the synthesis method of isooctanol polyoxyethylene ether isooctanoate is not reported. In general, organic acid is directly used as a catalyst for esterification reaction, such as sulfuric acid, methanesulfonic acid or p-toluenesulfonic acid, and the reaction effect is good, but the catalysts also have the defects of many byproducts, easy corrosion of equipment and the like, and the byproducts include dioxane. Dioxane is irritant to ear, nose and throat, and the content of dioxane in cosmetics and personal care products is required to be not more than 10ppm after 12 months and 31 years 2022.

The factors influencing the content of dioxane in isooctanol polyoxyethylene ether isooctanoate are two: firstly, free ethylene oxide in isooctanol polyoxyethylene ether can cause generation of dioxane in downstream esterification products, and the free ethylene oxide residue in the common process in the isooctanol polyoxyethylene ether is more and even reaches 300 ppm; secondly, esterification is carried out under the action of acid catalysis, EO chain is split to form a byproduct dioxane, and the content of the dioxane in the esterified product is up to thousands of ppm.

Disclosure of Invention

Aiming at the problems in the background art, the invention aims to provide a method for preparing isooctanol polyoxyethylene ether isooctoate, which solves the problem of higher content of byproduct dioxane in the preparation process and enables the product to be suitable for being added into cosmetics and skin care products.

In order to achieve the purpose, the invention is realized by the following technical scheme:

a preparation method of isooctanol polyoxyethylene ether isooctoate comprises the following steps:

s1, carrying out a polymerization reaction under the action of a polymerization catalyst by using isooctyl alcohol and ethylene oxide as raw materials, and carrying out bubbling degassing for 1-3 hours by using nitrogen after the reaction is finished to obtain isooctyl alcohol polyoxyethylene ether;

s2, adding reaction amount of isooctanol polyoxyethylene ether and isooctanoic acid into a flask, adding a certain amount of esterification catalyst while stirring, and slowly heating;

s3, timely separating out water under the condition of nitrogen flow, and filtering to obtain a colorless to yellowish transparent product.

In said S1, the molar ratio of isooctyl alcohol to ethylene oxide is 1: 3-10. The nitrogen bubbling flow rate is 5-10 ml/min.

In the S1, the polymerization catalyst is a solid basic catalyst, such as potassium hydroxide or sodium hydroxide. The addition amount of the polymerization catalyst is 0.01-0.5% of the total weight of isooctyl alcohol and ethylene oxide.

In the S2, the molar ratio of isooctanol polyoxyethylene ether to isooctanoic acid is 1: 0.9-1.0.

The esterification catalyst is a solid basic catalyst, such as solid potassium hydroxide or sodium hydroxide. The addition amount of the esterification catalyst is 0.1-0.3 percent of the total weight of isooctanol polyoxyethylene ether and isooctanoic acid.

In S3, the method for separating water under nitrogen flow includes: keeping the temperature for 5 hours under the reaction condition of 160-170 ℃, cooling to 70 ℃, and filtering to obtain a colorless to yellowish transparent product.

The polymerization equation in S1 is:

wherein n is 3 to 10.

The dehydration esterification reaction equation in S2 is:

wherein n is 3 to 10.

The isooctanol polyoxyethylene ether isooctanoic acid ester is prepared through polymerizing isooctanol and epoxy ethane to obtain isooctanol polyoxyethylene ether, and then carrying out dehydration esterification reaction with isooctanoic acid under the action of solid base catalyst.

The esterification reaction adopts a solid catalyst, so that the problem that the product has too dark color due to too strong alkalinity of an aqueous solution is solved.

Compared with the prior art, the invention has the following beneficial effects:

1. the invention adopts the solid alkaline catalyst to carry out polymerization reaction, and carries out esterification reaction under the action of the solid alkaline catalyst, so that the process is simple, the side reaction is less, and the cost can be effectively reduced;

2. degassing under nitrogen bubbling to make residual free ethylene oxide less than or equal to 10 ppm;

3. the invention has mild reaction conditions and simple adopted equipment, thereby saving equipment investment and energy consumption;

4. the content of dioxane in isooctanol polyoxyethylene ether isooctoate prepared by the method is less than or equal to 10ppm, and the isooctanol polyoxyethylene ether isooctoate has excellent spreadability, absorbability, nonirritant and the like;

5. the preparation process of the invention hardly pollutes the environment, meets the current environmental protection requirement and is worthy of popularization.

Detailed Description

The present invention will be further described with reference to the following specific examples, but the scope of the present invention is not limited thereto.

Isooctanol, ethylene oxide, isooctanoic acid and catalyst bases (sodium hydroxide and potassium hydroxide) are commercially available for use in the following examples and comparative examples.

The formula of the dehydration condensation reaction in the preparation method of the invention is as follows:

the formula of the dehydration esterification reaction in the preparation method is as follows:

wherein n is 3 to 10.

In the following examples and comparative examples, the residual free ethylene oxide content was measured by headspace gas GC-HS; the dioxane content was determined by gas chromatography-mass spectrometry (GC-MS).

Example 1

Adding 130g of isooctanol and 0.13g of KOH solid into a high-pressure reaction kettle, heating to 80 ℃, carrying out vacuum dehydration for 1 hour, slowly dropwise adding 132g of ethylene oxide, carrying out reaction for 3 hours at 150-160 ℃, carrying out basically complete reaction, cooling to 100 ℃, carrying out bubbling degassing for 2 hours, controlling the nitrogen flow to be 5ml/min, controlling the vacuum to be below-0.090 MPa, cooling to below 80 ℃, discharging to obtain isooctanol polyoxyethylene ether, and measuring the content of free ethylene oxide to be 1.0 ppm;

adding 200 g of isooctanol polyoxyethylene ether and 110 g of isooctanol into a flask, adding 0.93 g of solid catalyst KOH under stirring, slowly heating, separating water under the condition of nitrogen flow, keeping the temperature for 5 hours under the reaction condition of 160-170 ℃, cooling to below 80 ℃ to obtain the product isooctanol polyoxyethylene ether isooctanol isooctoate, and measuring the content of the dioxane to be 8.2 ppm.

Comparative example 1

As with the other conditions of example 1, no nitrogen sparge was used, except for vacuum degassing. The content of free ethylene oxide in isooctanol polyoxyethylene ether is 56ppm, and the content of dioxane in the isooctanol polyoxyethylene ether isooctoate is 160 ppm.

Example 2

Adding 130g of isooctanol and 0.35g of KOH solid into a high-pressure reaction kettle, heating to 80 ℃, carrying out vacuum dehydration for 1 hour, slowly dropwise adding 220g of ethylene oxide, carrying out reaction for 3 hours at 150-160 ℃, carrying out basically complete reaction, cooling to 100 ℃, carrying out bubbling degassing for 1 hour, controlling the nitrogen flow to be 6ml/min, controlling the vacuum to be below-0.090 MPa, cooling to below 80 ℃, discharging to obtain isooctanol polyoxyethylene ether, and measuring the content of free ethylene oxide to be 0.8 ppm;

adding 200 g of isooctanol polyoxyethylene ether and 82.28 g of isooctanol into a flask, adding 0.85 g of a solid catalyst KOH under stirring, slowly heating, separating water under the condition of nitrogen flow, keeping the temperature for 5 hours under the reaction condition of 160-170 ℃, cooling to below 80 ℃ to obtain the isooctanol polyoxyethylene ether isooctoate, and measuring the content of the dioxane to be 7.6 ppm.

Comparative example 2

The same other conditions as in example 2 were followed except that p-toluenesulfonic acid was used as the esterification catalyst. The dioxane content of the isooctyl alcohol polyoxyethylene ether isooctanoate is 700 ppm.

Example 3

Adding 130g of isooctanol and 1.45g of KOH solid into a high-pressure reaction kettle, heating to 80 ℃, carrying out vacuum dehydration for 1 hour, slowly dropwise adding 352g of ethylene oxide, reacting for 3 hours at 150-160 ℃, carrying out almost complete reaction, cooling to 100 ℃, carrying out bubbling degassing for 1 hour, controlling the nitrogen flow to be 8ml/min, controlling the vacuum to be below-0.090 MPa, cooling to below 80 ℃, and discharging to obtain isooctanol polyoxyethylene ether, wherein the content of free ethylene oxide is 0.5 ppm;

adding 200 g of isooctanol polyoxyethylene ether and 56.76 g of isooctanol into a flask, adding 0.51 g of catalyst KOH under stirring, slowly heating, separating water under the condition of nitrogen flow, keeping the temperature for 5 hours under the reaction condition of 160-170 ℃, cooling to below 80 ℃ to obtain the isooctanol polyoxyethylene ether isooctanol ester, and measuring the content of the dioxane to be 6.2 ppm.

Comparative example 3

As with the other conditions of example 3, no nitrogen bubbling was used and only vacuum degassing was used. The content of free ethylene oxide in isooctanol polyoxyethylene ether is 22ppm, and the content of dioxane in the isooctanol polyoxyethylene ether isooctoate is 80 ppm.

Example 4

Adding 130g of isooctanol and 2.85g of KOH solid into a high-pressure reaction kettle, heating to 80 ℃, carrying out vacuum dehydration for 1 hour, slowly dropwise adding 440g of ethylene oxide, reacting for 3 hours at 150-160 ℃, carrying out basically complete reaction, cooling to 100 ℃, carrying out bubbling degassing for 1 hour, carrying out nitrogen flow of 10ml/min, controlling the vacuum to be below-0.090 MPa, cooling to below 80 ℃, discharging to obtain isooctanol polyoxyethylene ether, and measuring the content of free ethylene oxide to be 0.45 ppm;

adding 200 g of isooctanol polyoxyethylene ether and 45.47 g of isooctanol into a flask, adding 0.25 g of catalyst KOH under stirring, slowly heating, separating water under the condition of nitrogen flow, keeping the temperature for 5 hours under the reaction condition of 160-170 ℃, cooling to below 80 ℃ to obtain the isooctanol polyoxyethylene ether isooctanol ester, and measuring the content of the dioxane to be 6.0 ppm.

Comparative example 4

As with the other conditions of example 3, without nitrogen bubbling, only vacuum degassing was used, and the esterification catalyst was p-toluenesulfonic acid, an acidic catalyst. The content of free ethylene oxide in isooctanol polyoxyethylene ether was 35ppm, and the dioxane content of isooctanol polyoxyethylene ether isooctanoate as a product was found to be 1621 ppm.

In conclusion, the invention adopts alkali as the catalyst to carry out polymerization reaction, and carries out esterification reaction under the action of the solid alkali catalyst, thereby having simple process, less side reaction and effectively reduced cost. Degassing under nitrogen bubbling to obtain residual free ethylene oxide content less than or equal to 5 ppm.

The invention has mild reaction condition and simple adopted equipment, thereby saving equipment investment and energy consumption. The isooctanol polyoxyethylene ether isooctoate prepared by the method has the dioxane content of less than or equal to 10ppm, and has excellent spreadability, absorbability, nonirritant and the like.

The preparation process of the invention hardly pollutes the environment, meets the current environmental protection requirement and is worthy of popularization.

The above-mentioned embodiments are only used for explaining the inventive concept of the present invention, and do not limit the protection of the claims of the present invention, and any insubstantial modifications of the present invention using this concept shall fall within the protection scope of the present invention.