CN110560159B

CN110560159B - Catalyst for preparing tertiary carbonic acid glycidyl ester and preparation method thereof

Info

Publication number: CN110560159B
Application number: CN201910743844.8A
Authority: CN
Inventors: 骆广生; 闫自飞; 王凯
Original assignee: Tsinghua University
Current assignee: Tsinghua University
Priority date: 2019-08-13
Filing date: 2019-08-13
Publication date: 2020-10-20
Anticipated expiration: 2039-08-13
Also published as: CN110560159A

Abstract

The invention relates to a catalyst for preparing tert-carbonic acid glycidyl ester, a preparation method and a method for preparing tert-carbonic acid glycidyl ester by adopting the catalyst. Wherein the catalyst is tetramethylammonium neodecanoate, and can catalyze the reaction of tertiary carbonic acid and epoxy chloropropane under homogeneous phase conditions. In the reaction process, the catalyst has the advantages of high catalytic selectivity, high reaction rate, homogeneous operation and the like, and when the catalyst is applied to the preparation of E10P, the utilization rate of tertiary carboxylic acid and epoxy chloropropane can be effectively improved, and the concentration of byproducts and the energy consumption in the process are reduced.

Description

Catalyst for preparing tertiary carbonic acid glycidyl ester and preparation method thereof

Technical Field

The invention belongs to the technical field of chemical catalysis, and particularly relates to a novel catalyst for preparing tertiary carbonic acid glycidyl ester and a preparation method thereof.

Background

The structural formula of the tertiary carbonic acid glycidyl ester (E10P) is shown as a formula I, wherein R1 and R2 are both saturated alkyl groups, the sum of carbon numbers of the saturated alkyl groups is 7, and the tertiary carbonic acid glycidyl ester is a mixture of isomers.

Tertiary carboxylic acid glycidyl ester (E10P)

The structure of the tertiary carboxylic acid glycidyl ester is composed of two parts: the tertiary carbon group on the left side is connected with the epoxy group on the right side through an ester bond. The epoxy group as active group can react with various matters with active hydrogen (such as carboxyl, amido and hydroxyl), which ensures that E10P can be introduced into various resins to play a role. The tertiary carbon group is used as a functional group of E10P, and can effectively reduce the interaction between chains after being embedded in a polymer chain, thereby reducing the viscosity of the polymer and greatly reducing the solvent consumption of the solvent-based coating. In addition, the tertiary carbon structure can also effectively absorb the energy of ultraviolet rays and improve the ultraviolet resistance of the coating. From the physical and chemical properties, the E10P has the characteristics of high boiling point and low viscosity, and the low viscosity ensures that the E10P can be used as a kettle bottom solvent to participate in resin polymerization reaction in a reactive diluent mode, so that organic solvents are reduced or even not suitable; the high boiling point allows the polymerization to be carried out at higher temperatures and without the need for pressurization to produce low viscosity, high solids resins.

Based on the above characteristics, E10P has been widely used in products such as acrylic paint, polyester and alkyd paint, polyurethane paint, cathodic electrophoretic paint, water-soluble paint, room temperature solid paint, etc. The current global market E10P demand is 4-6 million tons/year, and it is believed that the market demand of E10P will increase year by year with further restrictions on VOC emissions from strict environmental protection policies.

There are two main processes for the production of E10P. One is a one-step synthesis process, which comprises mixing tertiary carbonic acid with strong inorganic base such as sodium hydroxide to generate sodium tertiary carbonate, and then dropping it into refluxing ECH (epichlorohydrin) to react to obtain E10P in one step. However, the viscosity of the process system is extremely high, the emulsification is easy, and the amount of ECH required is large. The other is a two-step synthesis process, firstly, under the action of an alkaline catalyst, the tertiary carbonic acid firstly reacts with Epoxy Chloropropane (ECH) to generate an intermediate halogenated alcohol ester of the tertiary carbonic acid, and then dehydrochlorination is carried out under the action of strong alkali to obtain E10P. The process is easy to generate side reaction in the first step reaction, and the reaction temperature, the using amount of the catalyst and the excess degree of ECH need to be strictly controlled. Moreover, because quaternary ammonium salt catalysts are commonly used at present, a large amount of byproducts are generated at the initial stage of the reaction, so that the selectivity of the product is reduced, and the difficulty of the subsequent separation and purification process is increased. Therefore, it is very necessary to develop a novel catalyst for preparing glycidyl versatate.

Disclosure of Invention

In order to solve the problems that in the prior art for producing the halogenated alcohol ester of versatic acid as the intermediate in the first step of E10P, a quaternary ammonium salt catalyst has low selectivity and byproducts of more dichloropropanol and heavy byproducts, the invention firstly provides a catalyst for preparing glycidyl versatate (E10P), wherein the structure of the catalyst is shown as a formula II,

in the formula II, R1 and R2 are both saturated alkyl groups, and the sum of the carbon numbers of the saturated alkyl groups is 7.

Further wherein the catalyst is tetramethylammonium neodecanoate (TMAN).

The invention also provides a preparation method of the catalyst, which comprises the following specific steps:

mixing a tetramethylammonium hydroxide pentahydrate (TMAH) and neodecanoic acid (versatic acid) in a molar ratio of 1:1, and carrying out acid-base neutralization reaction at normal temperature to obtain a catalyst which contains a small amount of water and can directly catalyze the reaction without refining; or

Adding tetramethylammonium chloride (TMAC) and sodium hydroxide or potassium hydroxide into absolute ethyl alcohol or methanol, wherein the mass ratio of alcohol to TMAC is 0.5-10: 1, the molar ratio of TMAC to alkali is 1:1, obtaining tetramethylammonium hydroxide (TMAH) alcohol solution after salt is sufficiently separated out and centrifugally separated, adding tertiary carbonic acid to react to obtain TMAN alcohol solution, and the TMAN alcohol solution can directly catalyze the reaction of tertiary carbonic acid and Epoxy Chloropropane (ECH), remove alcohol in the subsequent refining process, or evaporate alcohol to obtain TMAN solid and then catalyze the TMAN solid.

Finally, the invention provides a preparation method of the tertiary carbonic acid glycidyl ester (E10P) by using the catalyst, wherein the preparation method comprises the specific steps of dissolving TMAN in tertiary carbonic acid, heating to a preset temperature, adding Epoxy Chloropropane (ECH) under the stirring condition, and controlling the temperature to react;

in the preparation process, when the acid value is lower than 1.5mg KOH/g, stopping heating to obtain E10P-M (halogenated alcohol versatate), and performing subsequent saponification and refining operations to obtain an E10P product;

preferably, the molar ratio of the catalyst TMAN to the tertiary carbonic acid is 0.01-0.5: 1.

Preferably, the molar ratio of the Epoxy Chloropropane (ECH) to the tertiary carbonic acid is 1-1.5: 1.

Preferably, the reaction temperature is controlled to be 40-120 ℃.

The invention has the beneficial effects that:

(1) the preparation method of the catalyst is homogeneous operation, and the reaction system is simple;

(2) by applying the catalyst disclosed by the invention, the selectivity of the reaction can be improved, the effective utilization rate of tertiary carboxylic acid and Epoxy Chloropropane (ECH) is increased, and the excess degree of ECH is reduced;

(3) the catalyst provided by the invention can reduce the concentration of heavy byproducts and the process energy consumption, greatly improves the production efficiency of the tertiary carbonic acid glycidyl ester, and has a wide market prospect.

Drawings

FIG. 1 shows a gas chromatogram of the product glycidyl versatate of example 11;

FIG. 2 shows a gas chromatogram of the product glycidyl versatate of example 12.

Detailed Description

The following detailed description of the embodiments is made with reference to the accompanying drawings, but the invention is not limited thereto.

The implementation steps of the invention are as follows: adding a certain amount of catalyst and tertiary carbonic acid into a three-neck flask, controlling the temperature by using an oil bath, stirring by using magnetic force, adding or dripping epoxy chloropropane at one time for reaction, continuously sampling to determine the acid value, and finishing the reaction in the first step when the acid value is lower than 3-1.5 mg KOH/g. Since the present invention focuses on the reaction of tertiary carboxylic acid and epichlorohydrin in the first step, the saponification in the second step and the subsequent purification are not discussed in detail. The specific reaction system is shown in table 1, and the specific meanings represented by the abbreviations of the materials in table 1 are as follows: tetramethylammonium neodecanoate-TMAN; versatic acid-C10; epichlorohydrin-ECH; dichloropropanol-DCH; halogenated alcohol ester of versatic acid-E10P-M; glycidyl versatate (E10P).

Table 1:

the experimental results are shown in fig. 1 and fig. 2, wherein a peak of solvent dichloromethane is shown at 1.79min, a peak of internal standard substance methyl benzoate is shown at 6.95min, a peak of product glycidyl versatate (E10P) is shown at 8-12.5 min, and a peak of intermediate halogenated alcohol versatate (E10P-M) is shown at 14.5-16.5 min in fig. 1 and fig. 2.

The influence of the catalyst concentration on the reaction process is examined in 1-3 groups of examples. In 4-7 groups of examples, the concentration of the catalyst is fixed, and the influence of temperature on the reaction process is examined. 8-10 groups of examples, and the influence of the addition amount of the ECH on the reaction process is examined. 11. Two sets of examples, are complete experiments conducted under optimal operating conditions.

The present invention is not limited to the above embodiments, and any changes or substitutions that can be easily made by those skilled in the art within the technical scope of the present invention are also within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A preparation method of tert-carbonic acid glycidyl ester E10P is characterized in that the structure of a catalyst used in the method is shown as a formula II,

in the formula II R₁，R₂Are saturated alkyl groups having a total carbon number of 7.

2. The method of claim 1, wherein the catalyst is TMAN.

3. The preparation method according to any one of claims 1-2, wherein the catalyst is prepared by mixing TMAH (tetramethylammonium hydroxide pentahydrate) and t-carbonic acid in a molar ratio of 1:1, and performing acid-base neutralization reaction at normal temperature to obtain a catalyst containing a trace amount of water and performing direct catalytic reaction without refining; or adding tetramethylammonium chloride TMAC and sodium hydroxide or potassium hydroxide into absolute ethyl alcohol or methanol, wherein the mass ratio of alcohol to TMAC is 0.5-10: 1, the molar ratio of TMAC to alkali is 1:1, obtaining tetramethylammonium hydroxide TMAH alcohol solution after salt is sufficiently separated out and centrifugally separated, adding tertiary carbonic acid to react to obtain TMAN alcohol solution, directly catalyzing the tertiary carbonic acid and epoxy chloropropane ECH to react, removing alcohol in the subsequent refining process, or evaporating alcohol to obtain TMAN solid and then catalyzing.

4. The preparation method according to claim 3, comprising the specific steps of dissolving TMAN in versatic acid, heating to a predetermined temperature, adding epichlorohydrin ECH under stirring, and controlling the temperature to perform the reaction.

5. The process according to claim 4, wherein the heating is stopped when the acid value is less than 1.5mgKOH/g during the preparation process to obtain the halogenated alcohol ester of E10P-M versatic acid, and the product E10P is obtained after subsequent saponification and refining operations.

6. The method according to any one of claims 4 to 5, wherein the molar ratio of the catalyst TMAN to the tertiary carboxylic acid is 0.01 to 0.5: 1.

7. The method according to any one of claims 4 to 5, wherein the molar ratio of epichlorohydrin ECH to versatic acid is 1 to 1.5: 1.

8. The method according to any one of claims 4 to 5, wherein the reaction temperature is controlled to 40 to 120 ℃.