Preparation method for bisphenol a bis(2-hydroxyethyl) ether

Abstract

The present invention belongs to the technical field of organic synthesis. Disclosed is a preparation method for bisphenol A bis(2-hydroxyethyl) ether. The specific steps of the preparation method are as follows: adding bisphenol A, a mixed acetate catalyst and a solvent into a reactor; starting stirring and performing replacement by nitrogen, raising the temperature to a reaction temperature, and then starting to feed ethylene oxide; after the addition of ethylene oxide is completed, maintaining the temperature and continuing the reaction until the pressure no longer decreases; cooling same to a desolventization temperature, performing desolventization until no more solvent comes out, then cooling same and degassing same, and discharging same to obtain the bisphenol A bis(2-hydroxyethyl) ether. The mixed acetate catalyst consists of calcium acetate, magnesium acetate and barium acetate; and the solvent is methyl cyclohexane. The preparation method of the present invention uses specific mixed acetates as a catalyst and methyl cyclohexane as a solvent, so that an excellent catalytic effect is achieved and the prepared bisphenol A bis(2-hydroxyethyl) ether is endowed with high purity, a low hydroxyl value and light color, and the solvent has low toxicity and is easy to recycle.

Description

A method for preparing dihydroxyethyl bisphenol A ether Technical Field

[0001] This invention relates to the field of organic synthesis technology, and specifically to a method for preparing dihydroxyethyl bisphenol A ether. Background Technology

[0002] Dihydroxyethyl bisphenol A ether is an important dihydroxy compound. Its unique molecular structure, with its benzene ring backbone, enhances the rigidity of the molecular chain, giving the material excellent mechanical strength and wear resistance during use. Simultaneously, the high degree of internal rotational freedom and flexibility of the polyether segments endow the material with excellent plasticity and toughness. These superior physicochemical properties make dihydroxyethyl bisphenol A ether suitable as a monomer for the synthesis of organic materials such as resins, coatings, adhesives, and glass fiber impregnators, as well as a modifier and additive for polymer chains, leading to its wide application in many fields including automotive manufacturing, textiles, aerospace, petrochemicals, construction, and transportation.

[0003] Currently, existing dihydroxyethyl bisphenol A polyethers typically employ solvent dissolution and high-temperature melting methods. Solvent dissolution requires solvent removal, a cumbersome process that significantly increases production costs, and most solvents are toxic and environmentally harmful. While high-temperature melting effectively overcomes the cumbersome process and environmental impact of solvent dissolution, the melting point of bisphenol A is around 158°C. Without heating the solvent, the heating medium must reach at least 160°C to melt the bisphenol A. The melted bisphenol A readily undergoes isomerization and decomposition reactions under high temperature and strong alkaline catalysts, leading to increased byproducts, a high hydroxyl value in the resulting product, and a darker, more chromatic product obtained under strong alkaline catalysis at high temperatures, significantly impacting product quality. Some preparation processes use alkylamines as catalysts, but this still fails to address the issue of dark product color, making it difficult to meet the demands of high-quality, high-performance products. Furthermore, catalyst removal processes are complex, energy-intensive, and costly. Summary of the Invention

[0004] In order to overcome the shortcomings of the prior art, the present invention aims to provide a method for preparing dihydroxyethyl bisphenol A ether. This method uses a specific mixed acetate as a catalyst and methylcyclohexane as a solvent, which not only has excellent catalytic effect, but also produces dihydroxyethyl bisphenol A ether with high content, low hydroxyl value and light color. In addition, the solvent has low toxicity and is easy to recover.

[0005] To solve the above problems, the technical solution adopted by the present invention is as follows:

[0006] A method for preparing dihydroxyethyl bisphenol A ether is as follows: Bisphenol A, mixed acetate catalyst and solvent are added to a reaction vessel, stirring is started and nitrogen gas is purged, the temperature is raised to the reaction temperature and ethylene oxide is introduced. After the ethylene oxide is added, the temperature is maintained and the reaction continues until the pressure no longer drops. The temperature is lowered to the desolventizing temperature and desolventizing is performed until no solvent is released. After cooling and degassing, the material is discharged to obtain the dihydroxyethyl bisphenol A ether.

[0007] The mixed acetate catalyst is composed of calcium acetate, magnesium acetate, and barium acetate; the solvent is methylcyclohexane.

[0008] In a preferred embodiment of the present invention, the mass ratio of calcium acetate, magnesium acetate and barium acetate in the mixed acetate catalyst is 1:1:0.5 to 1.

[0009] In a preferred embodiment of the present invention, the amount of the mixed acetate catalyst is 0.1% to 1% of the sum of the masses of bisphenol A and ethylene oxide.

[0010] More preferably, the amount of the mixed acetate catalyst is 0.4% of the sum of the masses of bisphenol A and ethylene oxide.

[0011] In a preferred embodiment of the present invention, the amount of methylcyclohexane added is 30% to 100% of the mass of bisphenol A, preferably 50%.

[0012] In a preferred embodiment of the present invention, the reaction temperature is 100-150°C and the reaction pressure is less than 0.50 MPa.

[0013] More preferably, the reaction temperature is 123±2℃ and the reaction pressure is less than 0.35Mpa.

[0014] In a preferred embodiment of the present invention, the desolventizing temperature is 90-110°C, preferably 100-105°C.

[0015] In a preferred embodiment of the present invention, the cooling is performed by cooling to 85°C and then degassing.

[0016] The dihydroxyethyl bisphenol A ether prepared by the method described in this invention has a content of ≥97%, a hydroxyl value of 325-385 mgKOH / g, and a color (Pt-Co) ≤35.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0018] 1. This invention employs a mixed acetate catalyst composed of calcium acetate, magnesium acetate, and barium acetate. The longer acetate chain gives it excellent catalytic properties. Simultaneously, calcium acetate, magnesium acetate, and barium acetate are all alkaline earth metal compound catalysts with divalent metal ions, capable of forming complexes with oxygen atoms in two polyether molecules simultaneously. Due to the large steric hindrance, the interaction between the metal and the polyether oxygen atoms is weakened, thereby slowing down the reaction rate between the epoxy monomer and the phenoxy anion. The product produced using this catalyst has a narrower relative molecular mass distribution and a lower content of small-molecule free alcohols, resulting in a dihydroxyethyl bisphenol A ether content ≥97%, a hydroxyl value of 325–385 mgKOH / g, and a color (Pt-Co) ≤35, indicating a lighter color. Compared to other conventional single-component alkaline earth metal catalysts, the product produced under the action of this catalyst has a superior color and a higher content of dihydroxyethyl bisphenol A ether.

[0019] 2. The preparation method of the present invention uses methylcyclohexane as a solvent, which is not only highly stable and has a low melting point, but also has low toxicity and is easy to recycle compared with other conventional solvents.

[0020] In summary, the preparation method of the present invention not only has excellent catalytic effect, resulting in high content, low hydroxyl value, and light color of the prepared dihydroxyethyl bisphenol A ether, but also has a simple process, is easy to implement industrially, and produces a product with high quality and stable performance. Attached Figure Description

[0021] Figure 1 is a physical image of the dihydroxyethyl bisphenol A ether obtained in Example 2 of the present invention;

[0022] Figure 2 is a physical image of the dihydroxyethyl bisphenol A ether prepared in Comparative Example 1 of the present invention;

[0023] Figure 3 is a physical image of the dihydroxyethyl bisphenol A ether prepared in Comparative Example 2 of the present invention;

[0024] Figure 4 is a physical image of the dihydroxyethyl bisphenol A ether prepared in Comparative Example 3 of the present invention.

[0025] Figure 5 is a physical image of the dihydroxyethyl bisphenol A ether prepared in Comparative Example 4 of the present invention.

[0026] Figure 6 is a physical image of the dihydroxyethyl bisphenol A ether prepared in Comparative Example 5 of the present invention.

[0027] Figure 7 is a physical image of the dihydroxyethyl bisphenol A ether prepared in Comparative Example 6 of the present invention;

[0028] Figure 8 is a physical image of the dihydroxyethyl bisphenol A ether prepared in Comparative Example 7 of the present invention.

[0029] Figure 9 is a physical image of the dihydroxyethyl bisphenol A ether prepared in Comparative Example 8 of this invention. Detailed Implementation

[0030] The preparation method of bis(hydroxyethyl) bisphenol A ether provided by the present invention is as follows: Bisphenol A, a mixed acetate catalyst composed of calcium acetate, magnesium acetate, and barium acetate, and solvent methylcyclohexane are added to a reaction vessel. After stirring is started, nitrogen gas is purged. The temperature is raised to a reaction temperature of 100-150°C, and then ethylene oxide is introduced. The reaction pressure during the reaction process is controlled to be below 0.50 MPa. After the ethylene oxide is added, the temperature is maintained and the reaction continues until the pressure no longer decreases. The temperature is lowered to a desolventizing temperature of 90-110°C, and desolventizing is carried out until no solvent is released. The temperature is then lowered to 85°C, degassing is performed for 30 minutes, and the material is discharged to obtain bis(hydroxyethyl) bisphenol A ether.

[0031] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0032] Example 1

[0033] The specific method for preparing a dihydroxyethyl bisphenol A ether is as follows:

[0034] In a reactor, 1000g of bisphenol A, 4.26g of mixed acetate catalyst (0.3% of the sum of the masses of bisphenol A and ethylene oxide, with the mass ratio of calcium acetate, magnesium acetate, and barium acetate in the mixed acetate catalyst being 1:1:0.7), and 500g of methylcyclohexane were added sequentially. After stirring, nitrogen gas was purged three times. Under vacuum conditions ≥-0.098 MPa, the temperature was raised to 110℃, and then 420g of ethylene oxide was continuously introduced, controlling the reaction temperature at 123±2℃ and the pressure inside the reactor ≤0.35 MPa. After the addition was complete, the temperature was maintained and the reaction continued until the pressure inside the reactor no longer decreased. The temperature was then lowered to 105℃ for solvent removal, controlling the solvent removal temperature at 100~105℃ until no solvent was released. The temperature was then lowered to 85℃ for degassing for 30 minutes, and the finished product was obtained after discharge.

[0035] The obtained product was analyzed by liquid chromatography and gas chromatography. The results are as follows: the content of dihydroxyethyl bisphenol A ether was 97.0%, the residual amount of methylcyclohexane was 283 ppm, the product color (Pt-Co) was 15.3, and the hydroxyl value determined by chemical method was 381.5 mg KOH / g.

[0036] Example 2

[0037] The specific method for preparing a dihydroxyethyl bisphenol A ether is as follows:

[0038] In a reactor, 1000g of bisphenol A, 5.68g of mixed acetate catalyst (0.4% of the sum of the masses of bisphenol A and ethylene oxide, with the mass ratio of calcium acetate, magnesium acetate, and barium acetate in the mixed acetate catalyst being 1:1:0.7), and 500g of methylcyclohexane were added sequentially. After stirring, nitrogen gas was purged three times. Under vacuum conditions ≥-0.098 MPa, the temperature was raised to 100℃, and then 420g of ethylene oxide was continuously introduced, controlling the reaction temperature at 123±2℃ and the pressure inside the reactor ≤0.35 MPa. After the addition was complete, the temperature was maintained and the reaction continued until the pressure inside the reactor no longer decreased. The temperature was then lowered to 105℃ for solvent removal, controlling the solvent removal temperature at 100~105℃ until no solvent was released. The temperature was then lowered to 85℃ for degassing for 30 minutes, and the finished product was obtained after discharge.

[0039] The obtained product was analyzed by liquid chromatography and gas chromatography. The results are as follows: the content of dihydroxyethyl bisphenol A ether was 99.2%, the residual amount of methylcyclohexane was 303 ppm, the product color (Pt-Co) was 14.5 (Figure 1), and the hydroxyl value determined by chemical method was 356.8 mg KOH / g.

[0040] Example 3

[0041] The specific method for preparing a dihydroxyethyl bisphenol A ether is as follows:

[0042] In a reactor, 1000g of bisphenol A, 7.10g of mixed acetate catalyst (0.5% of the sum of the masses of bisphenol A and ethylene oxide, with the mass ratio of calcium acetate, magnesium acetate, and barium acetate in the mixed acetate catalyst being 1:1:0.7), and 500g of methylcyclohexane were added sequentially. After stirring, nitrogen gas was purged three times. Under vacuum conditions ≥-0.098 MPa, the temperature was raised to 121℃, and then 420g of ethylene oxide was continuously introduced, controlling the reaction temperature at 123±2℃ and the pressure inside the reactor ≤0.35 MPa. After the addition was complete, the temperature was maintained and the reaction continued until the pressure inside the reactor no longer decreased. The temperature was then lowered to 105℃ for solvent removal, controlling the solvent removal temperature at 100~105℃ until no solvent was released. The temperature was then lowered to 85℃ for degassing for 30 minutes, and the finished product was obtained after discharge.

[0043] The obtained product was analyzed by liquid chromatography and gas chromatography. The results are as follows: the content of dihydroxyethyl bisphenol A ether was 99.3%, the residual amount of methylcyclohexane was 287 ppm, the product color (Pt-Co) was 29.7, and the hydroxyl value determined by chemical method was 355.1 mgKOH / g.

[0044] Example 4

[0045] The specific method for preparing a dihydroxyethyl bisphenol A ether is as follows:

[0046] In a reactor, 1000g of bisphenol A, 5.68g of mixed acetate catalyst (0.4% of the sum of the masses of bisphenol A and ethylene oxide, with the mass ratio of calcium acetate, magnesium acetate, and barium acetate in the mixed acetate catalyst being 1:1:0.7), and 500g of methylcyclohexane were added sequentially. After stirring, nitrogen gas was purged three times. Under vacuum conditions ≥-0.098 MPa, the temperature was raised to 110℃, and then 420g of ethylene oxide was continuously introduced, controlling the reaction temperature at 110±2℃ and the pressure inside the reactor ≤0.35 MPa. After the addition was complete, the temperature was maintained and the reaction continued until the pressure inside the reactor no longer decreased. The temperature was then lowered to 105℃ for solvent removal, controlling the solvent removal temperature at 100~105℃ until no solvent was released. The temperature was then lowered to 85℃ for degassing for 30 minutes, and the finished product was obtained after discharge.

[0047] The obtained product was analyzed by liquid chromatography and gas chromatography. The results are as follows: the content of dihydroxyethyl bisphenol A ether was 97.2%, the residual amount of methylcyclohexane was 293 ppm, the product color (Pt-Co) was 16.1, and the hydroxyl value determined by chemical method was 383.1 mgKOH / g.

[0048] Example 5

[0049] The specific method for preparing a dihydroxyethyl bisphenol A ether is as follows:

[0050] In a reactor, 1000g of bisphenol A, 5.68g of a mixed acetate catalyst (0.4% of the sum of the masses of bisphenol A and ethylene oxide, with the mass ratio of calcium acetate, magnesium acetate, and barium acetate in the mixed acetate catalyst being 1:1:0.7), and 500g of methylcyclohexane were added sequentially. After stirring, nitrogen was purged three times. Under a vacuum of ≥-0.098 MPa, the temperature was raised to 110℃, and then 420g of ethylene oxide was continuously introduced, controlling the reaction temperature at 140±2℃ and the pressure inside the reactor ≤0.35 MPa. After the addition was complete, the temperature was maintained and the reaction continued until the pressure inside the reactor no longer decreased. The temperature was then lowered to 120℃ for solvent removal, controlling the solvent removal temperature at 100~105℃ until no solvent was released. The temperature was then lowered to 85℃ for degassing for 30 minutes, and the finished product was obtained after discharge.

[0051] The obtained product was analyzed by liquid chromatography and gas chromatography. The results are as follows: the content of dihydroxyethyl bisphenol A ether was 98.6%, the residual amount of methylcyclohexane was 311 ppm, the product color (Pt-Co) was 34.1, and the hydroxyl value determined by chemical method was 357.2 mgKOH / g.

[0052] Example 6

[0053] The specific method for preparing a dihydroxyethyl bisphenol A ether is as follows:

[0054] In a reactor, 1000g of bisphenol A, 5.68g of a mixed acetate catalyst (0.4% of the sum of the masses of bisphenol A and ethylene oxide, with the mass ratio of calcium acetate, magnesium acetate, and barium acetate in the mixed acetate catalyst being 1:1:0.5), and 500g of methylcyclohexane were added sequentially. After stirring, nitrogen was purged three times. Under a vacuum of ≥-0.098 MPa, the temperature was raised to 100℃, and then 420g of ethylene oxide was continuously introduced, controlling the reaction temperature at 123±2℃ and the pressure inside the reactor ≤0.35 MPa. After the addition was complete, the temperature was maintained and the reaction continued until the pressure inside the reactor no longer decreased. The temperature was then lowered to 105℃ for solvent removal, controlling the solvent removal temperature at 100~105℃ until no solvent was released. The temperature was then lowered to 85℃ for degassing for 30 minutes, and the finished product was obtained after discharge.

[0055] The obtained product was analyzed by liquid chromatography and gas chromatography. The results are as follows: the content of dihydroxyethyl bisphenol A ether was 99.0%, the residual amount of methylcyclohexane was 308 ppm, the product color (Pt-Co) was 31.2, and the hydroxyl value determined by chemical method was 357.8 mgKOH / g.

[0056] Example 7

[0057] The specific method for preparing a dihydroxyethyl bisphenol A ether is as follows:

[0058] In a reactor, 1000g of bisphenol A, 5.68g of mixed acetate catalyst (0.4% of the sum of the masses of bisphenol A and ethylene oxide, with the mass ratio of calcium acetate, magnesium acetate, and barium acetate in the mixed acetate catalyst being 1:1:1), and 500g of methylcyclohexane were added sequentially. After stirring, nitrogen gas was purged three times. Under vacuum conditions ≥-0.098 MPa, the temperature was raised to 100℃, and then 420g of ethylene oxide was continuously introduced, controlling the reaction temperature at 123±2℃ and the pressure inside the reactor ≤0.35 MPa. After the addition was complete, the temperature was maintained and the reaction continued until the pressure inside the reactor no longer decreased. The temperature was then lowered to 105℃ for solvent removal, controlling the solvent removal temperature at 100~105℃ until no solvent was released. The temperature was then lowered to 85℃ for degassing for 30 minutes, and the finished product was obtained after discharge.

[0059] The obtained product was analyzed by liquid chromatography and gas chromatography. The results are as follows: the content of dihydroxyethyl bisphenol A ether was 98.2%, the residual amount of methylcyclohexane was 300 ppm, the product color (Pt-Co) was 16.5, and the hydroxyl value determined by chemical method was 376.8 mg KOH / g.

[0060] Comparative Example 1

[0061] The specific method for preparing a dihydroxyethyl bisphenol A ether is as follows:

[0062] 1000g of bisphenol A, 5.68g of KOH (0.4% of the sum of the masses of bisphenol A and ethylene oxide), and 500g of methylcyclohexane were sequentially added to a reactor. After stirring, nitrogen gas was purged three times. Under vacuum conditions ≥-0.098 MPa, the temperature was raised to 110℃, and then 420g of ethylene oxide was continuously introduced. The reaction temperature was controlled at 123±2℃, and the pressure inside the reactor was ≤0.35 MPa. After the addition was complete, the temperature was maintained and the reaction continued until the pressure inside the reactor no longer decreased. The temperature was then lowered to 105℃ for solvent removal. The solvent removal temperature was controlled at 100~105℃ until no solvent was released. The temperature was then lowered to 85℃ for degassing for 30 minutes. After discharge, the finished product was obtained.

[0063] The obtained product was analyzed by liquid chromatography and gas chromatography. The results are as follows: the content of dihydroxyethyl bisphenol A ether was 97.2%, the residual amount of methylcyclohexane was 331 ppm, the product color (Pt-Co) was 61.4 (Figure 2), and the hydroxyl value determined by chemical method was 360.1 mg KOH / g.

[0064] Comparative Example 2

[0065] The specific method for preparing a dihydroxyethyl bisphenol A ether is as follows:

[0066] 1000g of bisphenol A, 5.68g of triethylamine (0.4% of the sum of the masses of bisphenol A and ethylene oxide), and 500g of methylcyclohexane were sequentially added to a reactor. After stirring, nitrogen gas was purged three times. Under vacuum conditions ≥-0.098 MPa, the temperature was raised to 110℃, and then 420g of ethylene oxide was continuously introduced. The reaction temperature was controlled at 123±2℃, and the pressure inside the reactor was ≤0.35 MPa. After the addition was complete, the temperature was maintained and the reaction continued until the pressure inside the reactor no longer decreased. The temperature was then lowered to 105℃ for solvent removal. The solvent removal temperature was controlled at 100~105℃ until no solvent was released. The temperature was then lowered to 85℃ for degassing for 30 minutes. After discharge, the finished product was obtained.

[0067] The obtained product was analyzed by liquid chromatography and gas chromatography. The results are as follows: the content of dihydroxyethyl bisphenol A ether was 99.0%, the residual amount of methylcyclohexane was 299 ppm, the product color (Pt-Co) was 41.6 (Figure 3), and the hydroxyl value determined by chemical method was 355.1 mgKOH / g.

[0068] Comparative Example 3

[0069] The specific method for preparing a dihydroxyethyl bisphenol A ether is as follows:

[0070] 1000g of bisphenol A, 5.68g of calcium acetate (0.4% of the sum of the masses of bisphenol A and ethylene oxide), and 500g of methylcyclohexane were sequentially added to a reactor. After stirring, nitrogen gas was purged three times. Under vacuum conditions ≥-0.098 MPa, the temperature was raised to 110℃, and then 420g of ethylene oxide was continuously introduced. The reaction temperature was controlled at 123±2℃, and the pressure inside the reactor was ≤0.35 MPa. After the addition was complete, the temperature was maintained and the reaction continued until the pressure inside the reactor no longer decreased. The temperature was then lowered to 105℃ for solvent removal. The solvent removal temperature was controlled at 100~105℃ until no solvent was released. The temperature was then lowered to 85℃ for degassing for 30 minutes. After discharge, the finished product was obtained.

[0071] The obtained product was analyzed by liquid chromatography and gas chromatography. The results are as follows: the content of dihydroxyethyl bisphenol A ether was 98.9%, the residual amount of methylcyclohexane was 325 ppm, the product color (Pt-Co) was 43.6 (Figure 4), and the hydroxyl value determined by chemical method was 356.1 mgKOH / g.

[0072] Comparative Example 4

[0073] The specific method for preparing a dihydroxyethyl bisphenol A ether is as follows:

[0074] 1000g of bisphenol A, 5.68g of magnesium acetate (0.4% of the sum of the masses of bisphenol A and ethylene oxide), and 500g of methylcyclohexane were sequentially added to a reactor. After stirring, nitrogen gas was purged three times. Under vacuum conditions ≥-0.098Mpa, the temperature was raised to 110℃, and then 420g of ethylene oxide was continuously introduced. The reaction temperature was controlled at 123±2℃, and the pressure inside the reactor was ≤0.35Mpa. After the addition was completed, the temperature was maintained and the reaction continued until the pressure inside the reactor no longer decreased. The temperature was then lowered to 105℃ for solvent removal. The solvent removal temperature was controlled at 100~105℃ until no solvent was released. The temperature was then lowered to 85℃ for degassing for 30min. After discharge, the finished product was obtained.

[0075] The obtained product was analyzed by liquid chromatography and gas chromatography. The results are as follows: the content of dihydroxyethyl bisphenol A ether was 90.3%, the residual amount of methylcyclohexane was 300 ppm, the product color (Pt-Co) was 21.3 (Figure 5), and the hydroxyl value determined by chemical method was 400.3 mg KOH / g.

[0076] Comparative Example 5

[0077] The specific method for preparing a dihydroxyethyl bisphenol A ether is as follows:

[0078] 1000g of bisphenol A, 5.68g of barium acetate (0.4% of the sum of the masses of bisphenol A and ethylene oxide), and 500g of methylcyclohexane were sequentially added to a reactor. After stirring, nitrogen gas was purged three times. Under vacuum conditions ≥-0.098 MPa, the temperature was raised to 110℃, and then 420g of ethylene oxide was continuously introduced. The reaction temperature was controlled at 123±2℃, and the pressure inside the reactor was ≤0.35 MPa. After the addition was complete, the temperature was maintained and the reaction continued until the pressure inside the reactor no longer decreased. The temperature was then lowered to 105℃ for solvent removal. The solvent removal temperature was controlled at 100~105℃ until no solvent was released. The temperature was then lowered to 85℃ for degassing for 30 minutes. After discharge, the finished product was obtained.

[0079] The obtained product was analyzed by liquid chromatography and gas chromatography. The results are as follows: the content of dihydroxyethyl bisphenol A ether was 97.3%, the residual amount of methylcyclohexane was 302 ppm, the product color (Pt-Co) was 29.1 (Figure 6), and the hydroxyl value determined by chemical method was 360.5 mg KOH / g.

[0080] Comparative Example 6

[0081] The specific method for preparing a dihydroxyethyl bisphenol A ether is as follows:

[0082] 1000g of bisphenol A, 5.68g of calcium carbonate (0.4% of the sum of the masses of bisphenol A and ethylene oxide), and 500g of methylcyclohexane were sequentially added to a reactor. After stirring, nitrogen gas was purged three times. Under vacuum conditions ≥-0.098Mpa, the temperature was raised to 110℃, and then 420g of ethylene oxide was continuously introduced. The reaction temperature was controlled at 123±2℃, and the pressure inside the reactor was ≤0.35Mpa. After the addition was completed, the temperature was maintained and the reaction continued until the pressure inside the reactor no longer decreased. The temperature was then lowered to 105℃ for solvent removal. The solvent removal temperature was controlled at 100~105℃ until no solvent was released. The temperature was then lowered to 85℃ for degassing for 30min. After discharge, the finished product was obtained.

[0083] The obtained product was analyzed by liquid chromatography and gas chromatography. The results are as follows: the content of dihydroxyethyl bisphenol A ether was 97.5%, the residual amount of methylcyclohexane was 299 ppm, the product color (Pt-Co) was 45.3 (Figure 7), and the hydroxyl value determined by chemical method was 358.9 mgKOH / g.

[0084] Comparative Example 7

[0085] The specific method for preparing a dihydroxyethyl bisphenol A ether is as follows:

[0086] 1000g of bisphenol A, 5.68g of mixed acetate catalyst (0.4% of the sum of the masses of bisphenol A and ethylene oxide, with the mass ratio of calcium acetate, magnesium acetate, and barium acetate in the mixed acetate catalyst being 1:1:0.7) and 500g of methylcyclohexane were sequentially added to the reactor. After stirring, nitrogen gas was purged three times. Under vacuum conditions ≥-0.098 MPa, the temperature was raised to 110℃, and then 420g of ethylene oxide was continuously introduced. The reaction temperature was controlled at 123±2℃, and the pressure inside the reactor was ≤0.35 MPa. After the addition was complete, the temperature was maintained and the reaction continued until the pressure inside the reactor no longer decreased. The temperature was then lowered to 85℃ for solvent removal, and the solvent removal temperature was controlled at 75~85℃ until no solvent was released. The temperature was then lowered to 85℃ for degassing for 30 minutes. After discharge, the finished product was obtained.

[0087] The obtained product was analyzed by liquid chromatography and gas chromatography. The results are as follows: the content of dihydroxyethyl bisphenol A ether was 97.9%, the residual amount of methylcyclohexane was 925 ppm, the product color (Pt-Co) was 16.7 (Figure 8), and the hydroxyl value determined by chemical method was 354.8 mg KOH / g.

[0088] Comparative Example 8

[0089] The specific method for preparing a dihydroxyethyl bisphenol A ether is as follows:

[0090] In a reactor, 1000g of bisphenol A, 5.68g of mixed acetate catalyst (0.4% of the sum of the masses of bisphenol A and ethylene oxide, with the mass ratio of calcium acetate, magnesium acetate, and barium acetate in the mixed acetate catalyst being 1:1:0.7), and 500g of methylcyclohexane were added sequentially. After stirring, nitrogen gas was purged three times. Under vacuum conditions ≥-0.098 MPa, the temperature was raised to 110℃, and then 420g of ethylene oxide was continuously introduced. The reaction temperature was controlled at 123±2℃, and the pressure inside the reactor was ≤0.35 MPa. After the addition was complete, the temperature was maintained and the reaction continued until the pressure inside the reactor no longer decreased. Solvent removal was then performed, with the solvent removal temperature controlled at 120~125℃ until no solvent was released. The temperature was then lowered to 85℃ for degassing for 30 minutes. After discharge, the finished product was obtained.

[0091] The obtained product was analyzed by liquid chromatography and gas chromatography. The results are as follows: the content of dihydroxyethyl bisphenol A ether was 98.3%, the residual amount of methylcyclohexane was 291 ppm, the product color (Pt-Co) was 32.2 (Figure 9), and the hydroxyl value determined by chemical method was 359.3 mgKOH / g.

[0092] The reaction conditions and product performance data of Examples 1-7 and Comparative Examples 1-8 are summarized, and the results are shown in Table 1.

[0093] Table 1. Statistical data of product performance indicators obtained under different implementation conditions.

[0094] Note: In the table above, A represents a mixed acetate catalyst, B represents KOH catalyst, C represents triethylamine catalyst, D represents calcium acetate catalyst, E represents magnesium acetate catalyst, F represents barium acetate catalyst, and G represents calcium carbonate catalyst.

[0095] As shown in Table 1, comparing Examples 1-3, it can be concluded that, under the condition that other conditions remain unchanged and only considering the amount of catalyst, if the amount of catalyst is less than 0.4%, the reaction will be incomplete due to insufficient catalyst, resulting in a higher hydroxyl value and a lower content of dihydroxyethyl bisphenol A ether, which is close to the index limit. If the amount of catalyst is higher than 0.4%, the color of dihydroxyethyl bisphenol A ether in the product will be darker.

[0096] Comparing Examples 2, 4, and 5, it can be concluded that, with other conditions remaining constant and only considering the reaction temperature, a reaction temperature of 123±2℃ (Example 2) is optimal. If the reaction temperature is lower than 123℃ (Example 4), the reaction is incomplete, resulting in a higher hydroxyl value and a lower content of dihydroxyethyl bisphenol A ether in the product. If the reaction temperature is higher than 123℃ (Example 5), although both the hydroxyl value and the content of dihydroxyethyl bisphenol A ether are better, the product color is darker.

[0097] Comparing Examples 2, 6, and 7, it can be concluded that, with other conditions remaining unchanged and only considering the component ratio in the catalyst, the optimal mass ratio of calcium acetate, magnesium acetate, and barium acetate is 1:1:0.7. Although the indicators of Examples 6 and 7 meet the standards, they are not as good as the product indicators of Example 2.

[0098] Comparing Examples 2, 7, and 8, it can be concluded that, with other conditions remaining constant and only considering the desolventizing temperature, a desolventizing temperature of 100–105°C (Example 2) is optimal. If the desolventizing temperature is lower than 100–105°C (Example 6), desolventizing is incomplete, resulting in a higher residual methylcyclohexane in the product. If the desolventizing temperature is higher than 100–105°C (Example 7), although the residual methylcyclohexane is lower, the product color is darker.

[0099] In summary, the optimal reaction conditions for the preparation method of the present invention are as follows: the mass of the solvent methylcyclohexane is 50% of the mass of bisphenol A; the mass ratio of calcium acetate, magnesium acetate, and barium acetate in the mixed acetate catalyst is 1:1:0.7; the amount of the mixed acetate catalyst is 0.4% of the sum of the mass of bisphenol A and ethylene oxide; the reaction temperature is 123±2℃, the reaction pressure is below 0.35MPa; and the desolventizing temperature is 100~105℃.

[0100] Comparing Comparative Examples 1 and 2 with Example 2, it can be seen that under optimal reaction conditions, considering only the type of catalyst, although commonly used catalysts can meet the hydroxyl value requirements, the resulting product has a darker color. This demonstrates that the mixed acetate catalyst used in this invention has the advantage of improving product color. Comparing Comparative Examples 3, 4, 5, and 6 with Example 2, it can be seen that under optimal reaction conditions, the mixed acetate catalyst used in this invention produces products with superior performance indicators compared to conventional single-component alkaline earth metal catalysts. This proves that the catalyst of this invention can achieve high content, low hydroxyl value, and light color of dihydroxyethyl bisphenol A ether.

[0101] Example 8

[0102] This embodiment aims to examine the reproducibility of the solvent. The specific steps of a method for preparing dihydroxyethyl bisphenol A ether are as follows:

[0103] 1000g of bisphenol A, 5.68g of mixed acetate catalyst (0.4% of the sum of bisphenol A and ethylene oxide, with a mass ratio of calcium acetate, magnesium acetate, and barium acetate of 1:1:0.7 in the mixed acetate catalyst), and 500g of methylcyclohexane were sequentially added to a reactor. After stirring, nitrogen was purged three times. Under a vacuum of ≥-0.098 MPa, the temperature was raised to 110℃, and then 420g of ethylene oxide was continuously introduced, controlling the reaction temperature at 123±2℃ and the pressure inside the reactor ≤0.35 MPa. After the addition was complete, the temperature was maintained and the reaction continued until the pressure inside the reactor no longer decreased. The temperature was then lowered to 105℃ for solvent removal, controlling the solvent removal temperature at 100~105℃ until no solvent was released. The temperature was then lowered to 85℃ for degassing for 30 minutes, and the product was obtained after discharge. Subsequently, the catalyst recovered by filtration was used for repeated experiments. If the recovered solvent mass was ≤300g, additional solvent was added to bring the mass to 500g.

[0104] The dihydroxyethyl bisphenol A ethers prepared in Example 8 were subjected to liquid chromatography and gas chromatography analysis, and the results are shown in Table 2.

[0105] Table 2. Product performance data obtained from repeated tests in Example 8.

[0106] The data shown in Table 2 indicate that even after the methylcyclohexane solvent used in this invention is recovered and reused 40 times, a dihydroxyethyl bisphenol A ether product with a content ≥98%, a color ≤30, and a hydroxyl value of approximately 345–365 mgKOH / g can still be obtained. This demonstrates that the preparation method of this invention not only has excellent catalytic effects, resulting in a high content, low hydroxyl value, and light color of the prepared dihydroxyethyl bisphenol A ether, but also features a simple process that is easy to implement industrially, and the resulting product has high quality and stable performance.

[0107] The above embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A process for the preparation of bis-hydroxyethyl bisphenol A ether, characterized in that: Bisphenol A, mixed acetate catalyst and solvent are added to the reactor. After stirring is started, nitrogen gas is purged. After the temperature is raised to the reaction temperature, ethylene oxide is introduced. After the ethylene oxide is added, the temperature is maintained and the reaction continues until the pressure no longer drops. After cooling to the desolventizing temperature, desolventizing is performed until no solvent comes out. After cooling and degassing, the material is discharged to obtain the dihydroxyethyl bisphenol A ether. The mixed acetate catalyst is composed of calcium acetate, magnesium acetate, and barium acetate; the solvent is methylcyclohexane.

2. The process for the preparation of bis-hydroxyethyl bisphenol A ether according to claim 1, characterized in that: The mass ratio of calcium acetate, magnesium acetate, and barium acetate in the mixed acetate catalyst is 1:1:0.5-1.

3. Process for the preparation of bis-hydroxyethyl bisphenol A ether according to claim 1 or 2, characterized in that: The amount of the mixed acetate catalyst is 0.1% to 1% of the sum of the mass of bisphenol A and ethylene oxide.

4. The process for the preparation of bis-hydroxyethyl bisphenol A ether according to claim 3, characterized in that: The amount of the mixed acetate catalyst is 0.4% of the sum of the masses of bisphenol A and ethylene oxide.

5. The process for the preparation of bis-hydroxyethyl bisphenol A ether according to claim 1 or 2, characterized in that: The amount of methylcyclohexane added is 30% to 100% of the mass of bisphenol A, preferably 50%.

6. The process for the preparation of bis-hydroxyethyl bisphenol A ether according to claim 1 or 2, characterized in that: The reaction temperature is 100–150°C and the reaction pressure is less than 0.50 MPa.

7. The process for the preparation of bis-hydroxyethyl bisphenol A ether according to claim 6, characterized in that: The reaction temperature is 123±2℃ and the reaction pressure is less than 0.35Mpa.

8. The process for the preparation of bis-hydroxyethyl bisphenol A ether according to claim 1 or 2, characterized in that: The desolventizing temperature is 90–110°C, preferably 100–105°C.

9. The method for preparing dihydroxyethyl bisphenol A ether according to claim 5, characterized in that: The cooling process involves cooling the temperature to 85°C and then degassing.

10. The process for the preparation of bis-hydroxyethyl bisphenol A ether according to claim 1 or 2, characterized in that: The content of the dihydroxyethyl bisphenol A ether is ≥97%, the hydroxyl value is 325~385mgKOH / g, and the color (Pt-Co) is ≤35.

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