Synthesis method of bisphenol A polyether

Abstract

The invention discloses a synthesis method of bisphenol A polyether, and belongs to the technical field of fine chemical synthesis. According to the synthesis method, bisphenol A is taken as an initiator, and a composite catalyst composed of carbonate, an amine compound and organic phosphine is adopted to catalyze ring-opening polymerization reaction of alkylene oxide, so that bisphenol A polyether with low hydroxyl value and light color is prepared. The problems that in the prior art, a product is prone to isomerization and decomposition under the action of a strong base catalyst, and the color and luster of the product are darkened are effectively solved.

Description

Technical Field

[0001] The invention relates to the technical field of fine chemical synthesis, and in particular to a method for synthesizing bisphenol A polyether. Background Art

[0002] Bisphenol A polyether is prepared by the addition polymerization of initiator bisphenol A and alkylene oxide in the presence of a catalyst. It is a non-ionic surfactant. Bisphenol A polyether products can be used as synthetic monomers for organic materials such as coatings, resins, adhesives, and glass fiber sizing agents. They are widely used in many fields such as automobile manufacturing, fabrics, aviation, petrochemicals, construction, and transportation.

[0003] At present, the existing bisphenol A polyethers usually have solvent dissolution method and high temperature melting method. Among them, the solvent dissolution method needs to remove the solvent, and the process is complicated and the production cost is greatly increased. In addition, most of the solvents are toxic and have a great impact on the environment. The high temperature melting method usually adds bisphenol A to the reactor, and under the protection of inert gas, heats the raw material to the melting point with steam or oil bath to melt the raw material, and then introduces epoxide to react under strong base catalysis. For example, the preparation process of bisphenol A polyethylene ether reported in patents CN101367714B and CN107216453A all uses KOH as a catalyst; the document "Synthesis of Narrow Distribution Bisphenol A Polyoxypropylene Ether" (Journal of Jiangnan University, Vol. 11, No. 2, pp. 212-215, 2012) uses bisphenol A and NaOH to react in cyclohexane to prepare bisphenol A polyoxypropylene ether. The high temperature melting method well overcomes the problems of complicated process and great impact on the environment in the solvent dissolution method. However, since the melting point of bisphenol A is about 158°C, without heating the solvent, the temperature of the heating medium must reach at least 160°C to melt bisphenol A. The melted bisphenol A is very likely to undergo isomerization and decomposition reactions under high temperature and strong alkali, which increases the number of by-products and the hydroxyl value of the resulting product. At the same time, the product obtained by strong alkali catalysis at high temperature becomes darker and has a higher chroma, which greatly affects the product quality.

[0004] Based on this, it is very necessary to develop a synthesis method of bisphenol A polyether to solve the problem that molten bisphenol A is prone to isomerization and decomposition reactions and the product color becomes darker. Summary of the invention

[0005] In order to overcome the shortcomings of the prior art, the purpose of the present invention is to provide a method for synthesizing bisphenol A polyether. The method uses bisphenol A as an initiator and a composite catalyst to catalyze the ring-opening polymerization of alkylene oxide to obtain bisphenol A polyether with low hydroxyl value and light color, thereby greatly improving the product quality.

[0006] To solve the above problems, the technical solution adopted by the present invention is as follows:

[0007] A method for synthesizing bisphenol A polyether comprises the following steps:

[0008] S1, adding bisphenol A and a composite catalyst into a reactor in sequence, heating the reactor until the bisphenol A is melted after replacing nitrogen, and starting stirring after the bisphenol A is completely melted; wherein the composite catalyst is composed of carbonate, amine compound and organic phosphine;

[0009] S2, adding alkylene oxide to the reactor to react, and keeping the temperature until the pressure in the reactor stops decreasing;

[0010] S3. After the reaction is completed, the reactor is cooled and degassed to obtain bisphenol A polyether.

[0011] As a preferred embodiment of the present invention, the mass percentages of carbonate, amine compound and organic phosphine in the composite catalyst are 3-20%: 4-45%: 35-93%.

[0012] Further preferably, the carbonate is potassium carbonate and / or sodium carbonate.

[0013] More preferably, the amine compound is one of trimethylamine, triethylamine, and N,N-dimethylethylamine, or a combination of any two or more thereof.

[0014] More preferably, the organic phosphine is one of triisopropylphosphine, diphenylphosphine oxide, tributylphosphine, triphenylphosphine, tri-tert-butylphosphine, or a combination of any two or more thereof.

[0015] In the above-mentioned synthesis method, a composite catalyst catalyzed by a mixture of carbonate, amine compounds and organic phosphine is used to catalyze the ring-opening polymerization reaction, which can effectively solve the problem that the product in the prior art is prone to isomerization and decomposition under the action of a strong base catalyst, and can effectively improve the product color. The applicant has found that carbonates such as potassium carbonate or sodium carbonate can form ethylene carbonate with ethylene oxide, and ethylene carbonate can greatly increase the solubility of bisphenol A, and can reduce the reaction temperature and promote the reaction to a certain extent, but the catalytic activity of potassium carbonate or sodium carbonate alone is relatively weak. Because amine compounds such as trimethylamine, triethylamine, N, N-dimethylethylamine have a lower boiling point, they are easy to volatilize and take off, effectively reducing the residual amount of the catalyst in the product, and amine catalysts are more active when synthesizing low molecular weight bisphenol A polyethers, but the use of too much amine catalyst has the risk of increasing the product color during the reaction process. Organic phosphines such as triisopropylphosphine, diphenylphosphine oxide, tributylphosphine, triphenylphosphine, and tri-tert-butylphosphine are organic weak bases, and the reaction process follows the mechanism of anionic ring-opening polymerization, but there is a large steric hindrance in its structure, which has a limiting effect on the distribution of the product. In addition, since the acidity of the phenolic hydroxyl group is stronger than that of the alcoholic hydroxyl group, the phenolic hydroxyl group in bisphenol A preferentially combines with the above-mentioned weakly basic catalyst, so that the self-polymerization side reaction of the epoxy monomer is suppressed. Among them, organic phosphine has high catalytic activity and selectivity as a catalyst. The present invention is to compound carbonate, amine compound and organic phosphine into a composite catalyst according to a specific ratio, and the above three components work together to form a composite active center that is conducive to the reaction, so as to achieve an unexpected catalytic effect.

[0016] In the above synthesis method, the sum of the mass percentages of the bisphenol A, the composite catalyst and the alkylene oxide is 100%, wherein the alkylene oxide is one or more of ethylene oxide, propylene oxide and 1,2-butylene oxide.

[0017] As a preferred embodiment of the present invention, the mass ratio of bisphenol A to the composite catalyst in step S1 is 1:0.0001-0.1.

[0018] As a preferred embodiment of the present invention, the mass ratio of bisphenol A to alkylene oxide in step S2 is 1:0.35-10.

[0019] As a preferred embodiment of the present invention, the heating temperature of step S1 is 160-220° C. The heating here refers to heating the reactor to heat the material in the reactor to 160-220° C., preferably 180° C.

[0020] As a preferred embodiment of the present invention, the specific operation of step S2 is as follows: start to slowly add a small amount of alkylene oxide to the reactor, and when the reaction temperature reaches 170°C, start to stably introduce alkylene oxide for reaction, and control the pressure of the reactor within 0.4MPa. After adding the alkylene oxide, keep the temperature and continue the reaction (referred to as continuous reaction) until the pressure of the reactor stops decreasing.

[0021] As a preferred embodiment of the present invention, the reaction temperature in step S2 is 150-180° C., preferably 170° C.; and the pressure of the reactor is controlled within 0.4 MPa.

[0022] As a preferred embodiment of the present invention, in step S3, the material temperature is cooled to below 115° C. and then degassed.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] The synthesis method of the present invention prepares bisphenol A polyether by compounding carbonate, amine compound and organic phosphine into a composite catalyst in a specific ratio, and applying the composite catalyst to an alkylene oxide ring-opening polymerization reaction with bisphenol A as an initiator. The three components in the composite catalyst work together to form a composite active center that is beneficial to the reaction, which can achieve higher catalytic efficiency and selectivity and greatly improve the catalytic effect. At the same time, because the composite catalyst has weak alkalinity, the problem that the product in the prior art is prone to isomerization and decomposition under the action of a strong base catalyst is well avoided. At the same time, there are few side reactions, the hydroxyl value of the product can be effectively reduced, and the color of the product can be improved, thereby greatly improving the product quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The present invention is a schematic diagram of the synthesis process of the bisphenol A polyether. DETAILED DESCRIPTION

[0026] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0027] like Figure 1 As shown, the synthesis method of bisphenol A polyether provided by the present invention comprises the following steps:

[0028] S1. Add bisphenol A and a composite catalyst to a reactor in sequence, replace the air in the reactor with nitrogen and heat the reactor, heat the material temperature to 160-220° C. to melt bisphenol A, and start stirring after all bisphenol A is melted; wherein the mass ratio of bisphenol A to the composite catalyst is 1:0.0001-0.1; and the composite catalyst is formed by mixing carbonate, amine compound and organic phosphine in mass percentages of 3-20%:4-45%:35-93%;

[0029] S2, slowly add a small amount of alkylene oxide to the reactor, and when the reaction temperature reaches 150-180° C., start to stably introduce alkylene oxide for reaction, and control the pressure of the reactor within 0.4 MPa. After adding the alkylene oxide, continue the reaction while keeping warm until the pressure of the reactor stops decreasing; wherein the mass ratio of bisphenol A to alkylene oxide is 1:0.35-10;

[0030] S3. After the reaction is completed, the temperature of the materials in the reactor is cooled to below 115° C. and then degassed to obtain a bisphenol A polyether product.

[0031] The synthesis method of the bisphenol A polyether of the present invention is further described below through specific examples.

[0032] In the following examples, the bisphenol A residue in the product was detected by high performance liquid chromatography, and the specific method was referred to Q / HMK 235-2017; the hydroxyl value was detected by GB / T 7383-2007, and the color was obtained by comparison with a standard colorimetric tube.

[0033] Example 1

[0034] A method for synthesizing bisphenol A polyether comprises the following steps:

[0035] S1. 1000 g of bisphenol A and 3.0 g of a composite catalyst (composed of a mixture of 0.5 g of potassium carbonate, 0.5 g of trimethylamine and 2.0 g of triisopropylphosphine) are added to a reactor in sequence, and the air in the reactor is replaced with nitrogen. The materials in the reactor are then heated to 180° C. and stirring is started after all the bisphenol A is melted.

[0036] S2. Start to slowly add a small amount of ethylene oxide to the reactor. When the reaction temperature reaches 150°C, it begins to stabilize. Ethylene oxide was introduced (the total amount of ethylene oxide added was 351 g), and the pressure of the reactor was controlled within 0.4 MPa. After the addition of ethylene oxide, the reaction was continued by keeping the temperature constant until the pressure stopped decreasing.

[0037] S3. After the reaction is completed, the temperature of the materials in the reactor is cooled to below 115° C. and then degassed for 30 minutes to obtain the bisphenol A polyether product.

[0038] The product obtained in this example was analyzed by high performance liquid chromatography, and the results were as follows: the residual amount of bisphenol A was 0 ppm; the color was No. 20 (Pt-Co unit); and the hydroxyl value determined by chemical method was 345 mgKOH / g.

[0039] Example 2

[0040] A method for synthesizing bisphenol A polyether comprises the following steps:

[0041] S1. Add 1000g of bisphenol A and 6.5g of a composite catalyst (composed of a mixture of 0.2g of sodium carbonate, 0.3g of potassium carbonate, 2.0g of N,N-dimethylethylamine and 4.0g of triphenylphosphine) into a reactor in sequence, replace the air in the reactor with nitrogen, and then heat the materials in the reactor to 180°C. Start stirring after all the bisphenol A is melted.

[0042] S2. Start to slowly add a small amount of propylene oxide to the reactor. When the reaction temperature reaches 160°C, start to steadily introduce propylene oxide (a total of 789 g of propylene oxide is added). Control the pressure of the reactor within 0.4 MPa. After adding propylene oxide, keep the temperature and continue the reaction until the pressure stops decreasing.

[0043] S3. After the reaction is completed, the temperature of the materials in the reactor is cooled to below 115° C. and then degassed for 30 minutes to obtain the bisphenol A polyether product.

[0044] The product obtained in this example was analyzed by high performance liquid chromatography, and the results were as follows: the residual amount of bisphenol A was 0 ppm; the color was No. 20 (Pt-Co unit); and the hydroxyl value determined by chemical method was 279 mgKOH / g.

[0045] Example 3

[0046] A method for synthesizing bisphenol A polyether comprises the following steps:

[0047] S1. 1000 g of bisphenol A and 3.9 g of a composite catalyst (composed of a mixture of 0.4 g of potassium carbonate, 1.0 g of triethylamine and 2.5 g of tributylphosphine) are added to a reactor in sequence, and the air in the reactor is replaced with nitrogen. The materials in the reactor are then heated to 180° C. and stirring is started after all the bisphenol A is melted.

[0048] S2. Start to slowly add a small amount of 1,2-butylene oxide to the reactor. When the reaction temperature reaches 170°C, start to steadily introduce 1,2-butylene oxide (a total of 1,2-butylene oxide added is 1263g). Control the pressure of the reactor within 0.4MPa. After adding propylene oxide, keep the temperature and continue the reaction until the pressure stops decreasing.

[0049] S3. After the reaction is completed, the temperature of the materials in the reactor is cooled to below 115° C. and then degassed for 30 minutes to obtain the bisphenol A polyether product.

[0050] The product obtained in this example was analyzed by high performance liquid chromatography, and the results were as follows: the residual amount of bisphenol A was 0 ppm; the color was No. 25 (Pt-Co unit); and the hydroxyl value determined by chemical method was 217 mgKOH / g.

[0051] Comparative Example 1

[0052] A method for synthesizing bisphenol A polyether comprises the following steps:

[0053] S1. Add 1000 g of bisphenol A and 4.2 g of KOH into a reactor in sequence, replace the air in the reactor with nitrogen, and then heat the materials in the reactor to 180° C. and start stirring after all the bisphenol A is melted.

[0054] S2. Start to slowly add a small amount of ethylene oxide to the reactor. When the reaction temperature reaches 150°C, start to steadily introduce ethylene oxide (a total of 351 g of ethylene oxide is added). Control the pressure of the reactor within 0.4 MPa. After adding ethylene oxide, keep the temperature and continue the reaction until the pressure stops decreasing.

[0055] S3. After the reaction is completed, the temperature of the materials in the reactor is cooled to below 115° C. and then degassed for 30 minutes to obtain the bisphenol A polyether product.

[0056] The product obtained in this example was analyzed by high performance liquid chromatography, and the results were as follows: the residual amount of bisphenol A was 16730 ppm; the color was 65 (Pt-Co unit); and the hydroxyl value determined by chemical method was 348 mgKOH / g.

[0057] By comparing Example 1 and Comparative Example 1, it can be seen that compared with a strong base catalyst, the bisphenol A polyether prepared by the ring-opening polymerization reaction of alkylene oxide catalyzed by the composite catalyst of the present invention has no bisphenol A residue, better color, and lower hydroxyl value, which shows that the synthesis method of the present invention greatly improves the product quality of bisphenol A polyether.

[0058] Comparative Examples 2-4

[0059] The difference between Comparative Examples 2-4 and Example 1 is that potassium carbonate, trimethylamine and triisopropylphosphine are used as catalysts respectively, and other reaction conditions are exactly the same. Specifically, the amount of catalyst used in Comparative Examples 2-4 and the bisphenol A residual amount, color and hydroxyl value of the bisphenol A polyether obtained are shown in Table 1.

[0060] Table 1 Catalyst dosage of comparative examples 2 to 4 and the bisphenol A residue, color and hydroxyl value of the obtained products

[0061] project Catalyst and its dosage Bisphenol A Residue (ppm) Color(No.) Hydroxyl value (mg KOH / g) Comparative Example 2 3.0g potassium carbonate catalyst 50 10 368 Comparative Example 3 3.0g trimethylamine 1280 80 343 Comparative Example 4 3.0g triisopropylphosphine 0 40 348

[0062] By comparing Comparative Example 2 and Example 1, it can be seen that the bisphenol A polyether obtained by using potassium carbonate catalyst alone has better color, but the residual amount of bisphenol A is high and the hydroxyl value is high. According to the analysis and detection standard of the hydroxyl value, the larger the hydroxyl value, the smaller the molecular weight. This shows that although the product obtained by using potassium carbonate catalyst alone has better color, the product quality is not as good as the composite catalyst used in Example 1.

[0063] By comparing Comparative Example 3 and Example 1, it can be seen that the hydroxyl value index of the bisphenol A polyether prepared by using trimethylamine catalyst alone is lower. The lower the hydroxyl value, the smaller the hydroxyl value, which indicates that the molecular weight is larger according to the analysis and detection standard of the hydroxyl value, indicating that trimethylamine as a catalyst makes the alkylene oxide reaction more thorough. However, the residual amount of bisphenol A is high and the color is relatively poor, indicating that the product prepared by using trimethylamine catalyst alone has better color, but the product quality is not as good as the composite catalyst used in Example 1.

[0064] By comparing Comparative Example 4 and Example 1, it can be seen that the bisphenol A polyether prepared by using only triisopropylphosphine catalyst has no bisphenol A residue, but the color is relatively poor and the hydroxyl value is high. According to the analysis and detection standard of the hydroxyl value, it is known that the larger the hydroxyl value, the smaller the molecular weight. This shows that although the product prepared by using only triisopropylphosphine catalysis has no bisphenol A residue, the product quality is not as good as the effect of the composite catalyst used in Example 1.

[0065] From the above analysis, it can be found that the composite catalyst of the present invention shows excellent effect in the preparation of bisphenol A polyether. The three components form a composite active center that is conducive to the reaction, thereby achieving a synergistic effect of 1+1+1>3 and realizing an unexpected catalytic effect.

[0066] The above-mentioned embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and substitutions made by technicians in this field on the basis of the present invention shall fall within the scope of protection required by the present invention.

Claims

1. A method for synthesizing bisphenol A polyether, characterized in that: The following steps are involved: S1, adding bisphenol A and a composite catalyst into a reactor in sequence, heating the reactor until the bisphenol A melts after replacing nitrogen, and starting stirring after the bisphenol A is completely melted; wherein the composite catalyst is composed of carbonate, amine compound and organic phosphine; S2, adding alkylene oxide to the reactor to react, and keeping the temperature until the pressure in the reactor stops decreasing; S3. After the reaction is completed, the reactor is cooled and degassed to obtain bisphenol A polyether.

2. The method for synthesizing bisphenol A polyether according to claim 1, wherein: The mass percentages of carbonate, amine compound and organic phosphine in the composite catalyst are 3-20%: 4-45%: 35-93%.

3. The method for synthesizing bisphenol A polyether according to claim 1 or 2, characterized in that: The carbonate is potassium carbonate and / or sodium carbonate.

4. The method for synthesizing bisphenol A polyether according to claim 1 or 2, characterized in that: The amine compound is one of trimethylamine, triethylamine and N,N-dimethylethylamine or a combination of any two or more thereof.

5. The method for synthesizing bisphenol A polyether according to claim 1 or 2, characterized in that: The organic phosphine is one of triisopropyl phosphine, diphenyl phosphine oxide, tributyl phosphine, triphenyl phosphine, tri-tert-butyl phosphine, or a combination of any two or more thereof.

6. The method for synthesizing bisphenol A polyether according to claim 1 or 2, characterized in that: The mass ratio of bisphenol A to the composite catalyst in step S1 is 1:0.0001-0.

1.

7. The method for synthesizing bisphenol A polyether according to claim 1 or 2, characterized in that: The mass ratio of bisphenol A to alkylene oxide in step S2 is 1:0.35-10.

8. The method for synthesizing bisphenol A polyether according to claim 1 or 2, characterized in that: The heating temperature in step S1 is 160-220°C.

9. The method for synthesizing bisphenol A polyether according to claim 1 or 2, characterized in that: The reaction temperature in step S2 is 150-180°C.

10. The method for synthesizing bisphenol A polyether according to claim 1 or 2, characterized in that: In step S3, the material temperature is cooled to below 115° C. and then degassed.

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