Modified titanate catalyst as well as preparation process and application thereof

Abstract

The invention relates to the technical field of high polymer materials, and discloses a modified titanate catalyst as well as a preparation process and application thereof. The preparation process of the modified titanate catalyst comprises the following steps: under a protective atmosphere, adding tetrabutyl titanate into a reaction container, controlling the temperature of a solution in the reaction container to be 60-80 DEG C, stirring, adding acetylacetone, and reacting to obtain a titanic acid-acetylacetone complex; the temperature of the solution in the reaction container is controlled to be 80-90 DEG C, stirring is kept, glycolic acid is added, and after a reaction, a modified titanate catalyst solution is prepared; and cooling the modified titanate catalyst solution to room temperature, and removing volatile components through reduced pressure distillation to prepare the powdery modified titanate catalyst. The modified titanate catalyst prepared by the invention is beneficial to improving the reaction rate and the reaction selectivity in a polyphenylene sulfide preparation process, so that the purity and the yield of the prepared PPS are improved.

Description

Technical Field

[0001] The present application relates to the field of polymer materials, and in particular to a modified titanate catalyst and a preparation process and application thereof. Background Art

[0002] Polyphenylene sulfide (PPS) is a high-performance polymer that is widely used in the electronics, electrical and automotive industries due to its excellent thermal stability, chemical resistance and mechanical strength. Currently, the main method for synthesizing PPS is the sodium sulfide method.

[0003] The sodium sulfide method is the most commonly used PPS synthesis method in the industry. PPS is prepared by condensation reaction of dichlorobenzene and anhydrous sodium sulfide in a polar solvent. The advantages of this method are that the raw materials are easily available and the product quality is good, but the disadvantages are that a large amount of sodium chloride by-product is produced, the waste liquid treatment is complicated and costly, the product purity is not high, and the yield is low.

[0004] Although the use of phenyl disulfide and cyclopentane sulfone to prepare PPS can reduce the generation of waste liquid, it also has problems such as low reaction rate, many side reactions, and low product purity. Summary of the invention

[0005] The main purpose of the present application is to provide a modified titanate catalyst and its preparation process and application, aiming to solve the problems of low reaction rate, many side reactions and low product purity in the existing PPS preparation process.

[0006] To achieve the above object, the present application proposes a preparation process of a modified titanate catalyst, comprising the following steps:

[0007] S10, under a protective atmosphere, adding tetrabutyl titanate into a reaction container, controlling the temperature of the solution in the reaction container to 60-80° C., stirring, adding acetylacetone, and obtaining a titanate acetylacetone complex after reaction;

[0008] S20, controlling the temperature of the solution in the reaction container to 80-90° C., maintaining stirring, adding glycolic acid, and obtaining a modified titanate catalyst solution after reaction;

[0009] S30, cooling the modified titanate catalyst solution obtained in step S20 to room temperature, removing volatile components by reduced pressure distillation, and obtaining a powdered modified titanate catalyst.

[0010] Optionally, the mass ratio of tetrabutyl titanate and acetylacetone in step S10 and the hydroxyacetic acid in step S20 is (80-90): (46-55): (17-20).

[0011] Optionally, the mass ratio of the tetrabutyl titanate, the acetylacetone, and the glycolic acid is 85:50:19.

[0012] Optionally, in step S20, glycolic acid is added to the titanate acetylacetonate complex at a feeding rate of 3 to 5 g / min.

[0013] Preferably, in step S20, glycolic acid is added to the titanate acetylacetonate complex at a feeding rate of 3.8 g / min.

[0014] Optionally, in step S10, the protective atmosphere is nitrogen.

[0015] Optionally, in step S10, stirring is performed at a stirring rate of 50 to 200 rpm for 1 to 2 hours.

[0016] Optionally, in step S20, stirring is performed at a stirring rate of 50 to 200 rpm for 2 to 3 hours.

[0017] The present application also proposes a modified titanate catalyst, which is prepared by using any of the above-mentioned preparation processes for the modified titanate catalyst.

[0018] The present application also proposes the use of a modified titanate catalyst in the preparation of polyphenylene sulfide.

[0019] Optionally, the raw materials for preparing the polyphenylene sulfide include phenol, hydrogen sulfide, sulfolane, and the modified titanate catalyst.

[0020] In the technical solution of the present application, the titanium center in tetrabutyl titanate is an electron-deficient center, which is easy to combine with the carbonyl oxygen atom of acetylacetone to form a titanate acetylacetone complex. The chemical formula of tetrabutyl titanate is Ti(OBu)4, the chemical formula of acetylacetone is AcAcH, and the chemical formula of the titanate acetylacetone complex is Ti(OAcAc).

[0021] Hydroxyacetic acid is added to the titanate acetylacetonate complex system. Hydroxyacetic acid has two active groups, namely carboxylic acid and hydroxyl groups. These two active groups can react with the titanate acetylacetonate complex to form a new organic titanium compound, namely a modified titanate catalyst. Among them, the chemical formula of hydroxyacetic acid is HOCH2COOH, and the chemical formula of the modified titanate catalyst is Ti(OAcAc)(OCH2COOH).

[0022] The volatile components in the reaction system, such as butanol and water, are removed by distillation under reduced pressure to obtain a relatively pure powdered modified titanate catalyst.

[0023] In the technical solution of the present application, tetrabutyl titanate and acetylacetone are used to form a titanate acetylacetone complex by coordination reaction, and hydroxyacetic acid is added. The hydroxyacetic acid is used as a modifier to further react with the titanate acetylacetone complex to form a new organic titanium compound, i.e., a modified titanate catalyst. The above preparation process not only increases the stability of the modified titanate catalyst, but also improves its catalytic performance, and the prepared modified titanate catalyst helps to improve the reaction rate and reaction selectivity in the preparation process of polyphenylene sulfide (PPS), so as to improve the purity and yield of the prepared PPS. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0025] It should be noted that if there are descriptions involving "first", "second", etc. in the embodiments of the present application, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing in the full text includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or a scheme that satisfies both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in the field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0026] Although the use of phenyl disulfide and cyclopentane sulfone to prepare PPS can reduce the generation of waste liquid, there are also problems such as low reaction rate, many side reactions, and low product purity. In view of this, the present application proposes a modified titanate catalyst and its preparation process and application, aiming to solve the problems of low reaction rate, many side reactions, and low product purity in the existing PPS preparation process.

[0027] In the present application, a process for preparing a modified titanate catalyst comprises the following steps:

[0028] S10, under a protective atmosphere, adding tetrabutyl titanate into a reaction container, controlling the temperature of the solution in the reaction container to 60-80° C., stirring, adding acetylacetone, and obtaining a titanate acetylacetone complex after reaction;

[0029] S20, controlling the temperature of the solution in the reaction container to 80-90° C., maintaining stirring, adding glycolic acid, and obtaining a modified titanate catalyst solution after reaction;

[0030] S30, cooling the modified titanate catalyst solution obtained in step S20 to room temperature, removing volatile components by reduced pressure distillation, and obtaining a powdered modified titanate catalyst.

[0031] By adopting the above technical solution, the titanium center in tetrabutyl titanate is an electron-deficient center, which is easy to combine with the carbonyl oxygen atom of acetylacetone to form a titanate acetylacetone complex. Among them, the chemical formula of tetrabutyl titanate is Ti(OBu)4, the chemical formula of acetylacetone is AcAcH, and the chemical formula of the titanate acetylacetone complex is Ti(OAcAc).

[0032] Hydroxyacetic acid is added to the titanate acetylacetonate complex system. Hydroxyacetic acid has two active groups, namely carboxylic acid and hydroxyl groups. These two active groups can react with the titanate acetylacetonate complex to form a new organic titanium compound, namely a modified titanate catalyst. Among them, the chemical formula of hydroxyacetic acid is HOCH2COOH, and the chemical formula of the modified titanate catalyst is Ti(OAcAc)(OCH2COOH).

[0033] The volatile components in the reaction system, such as butanol and water, are removed by distillation under reduced pressure to obtain a relatively pure powdered modified titanate catalyst.

[0034] In the technical solution of the present application, tetrabutyl titanate is used to react with acetylacetone to form a titanate acetylacetone complex, and hydroxyacetic acid is added. The hydroxyacetic acid is used as a modifier to further react with the titanate acetylacetone complex to form a new organic titanium compound, i.e., a modified titanate catalyst. The above preparation process not only increases the stability of the modified titanate catalyst, but also improves its catalytic performance, and the prepared modified titanate catalyst helps to improve the reaction rate and reaction selectivity in the preparation process of polyphenylene sulfide (PPS), so as to improve the purity and yield of the prepared PPS.

[0035] Furthermore, the mass ratio of tetrabutyl titanate and acetylacetone in step S10 and the glycolic acid in step S20 is (80-90):(46-55):(17-20).

[0036] By adopting the above technical scheme and controlling the dosage ratio of tetrabutyl titanate, acetylacetone and glycolic acid, a modified titanate catalyst with good stability and catalytic performance can be prepared, and the yield of the prepared modified titanate catalyst is high.

[0037] Furthermore, the mass ratio of the tetrabutyl titanate, the acetylacetone, and the glycolic acid is 85:50:19.

[0038] By adopting the above technical solution, the present application can improve the yield of the prepared modified titanate catalyst by further optimizing the dosage ratio of tetrabutyl titanate, acetylacetone and glycolic acid.

[0039] Furthermore, in the step S20, glycolic acid is added to the titanate acetylacetonate complex at a feeding rate of 3 to 5 g / min.

[0040] By adopting the above technical solution and controlling the feeding rate of hydroxyacetic acid, hydroxyacetic acid and titanate acetylacetonate complex can be brought into more complete contact and react more fully, thereby improving the yield of the prepared modified titanate catalyst.

[0041] Furthermore, in the step S20, glycolic acid is added to the titanate acetylacetonate complex at a feeding rate of 3.8 g / min.

[0042] Furthermore, in step S10, the protective atmosphere is nitrogen, which can isolate oxygen and other active gases in the air and prevent unnecessary chemical reactions, thereby ensuring the smooth progress of the reaction and the purity of the target product.

[0043] Furthermore, in the step S10, the stirring time is 1 to 2 hours. Under the condition of stirring for 1 to 2 hours, acetylacetone and tetrabutyl titanate can react sufficiently to generate acetylacetone titanate complex.

[0044] Furthermore, in the step S20, the stirring time is 2 to 3 hours. Hydroxyacetic acid and the titanate acetylacetonate complex can react sufficiently under the condition of stirring for 2 to 3 hours to generate a modified titanate catalyst.

[0045] The present application also proposes a modified titanate catalyst, which is prepared by any of the above-mentioned preparation processes for the modified titanate catalyst. By adopting the above-mentioned technical scheme, the yield of the modified titanate catalyst prepared by the present application is greater than 90%.

[0046] The present application also proposes the use of the modified titanate catalyst in the preparation of polyphenylene sulfide.

[0047] Specifically, the raw materials for preparing the polyphenylene sulfide include phenol, hydrogen sulfide, cyclopentane, and the modified titanate catalyst. The modified titanate catalyst prepared by the present application can improve the reaction rate and selectivity in the preparation process of polyphenylene sulfide (PPS), so as to improve the purity and yield of the prepared PPS.

[0048] The technical solution of the present application is further described in detail below in conjunction with specific embodiments. It should be understood that the following embodiments are only used to explain the present application and are not used to limit the present application.

[0049] Example 1

[0050] A preparation process of a modified titanate catalyst comprises the following steps:

[0051] S10, under a nitrogen atmosphere, adding 85 g of tetrabutyl titanate (purity 99%) into a reaction vessel, controlling the temperature of the solution in the reaction vessel to 70° C., stirring at a stirring rate of 100 rpm, adding 50 g of acetylacetone (purity ≥ 99.6%) at a feeding rate of 10 g / min, stirring for 1 h, and obtaining a titanate acetylacetone complex after reaction;

[0052] S20, maintaining the nitrogen protective atmosphere, controlling the temperature of the solution in the reaction container to 80° C., maintaining the stirring rate at 100 rpm for stirring, adding 18 g of hydroxyacetic acid (purity of 99%) at a feeding rate of 5 g / min, stirring for 2 h, and obtaining a modified titanate catalyst solution after reaction;

[0053] S30, cooling the modified titanate catalyst solution obtained in step S20 to room temperature (25°C), removing volatile components by reduced pressure distillation, and obtaining a powdered modified titanate catalyst.

[0054] It was measured that the yield of the modified titanate catalyst prepared in this example was 90.97%.

[0055] Example 2

[0056] This embodiment is based on Embodiment 1, and the difference is that in step S20, the amount of glycolic acid added is 17 g.

[0057] It was measured that the yield of the modified titanate catalyst prepared in this example was 90.03%.

[0058] Example 3

[0059] This embodiment is based on Embodiment 1, and the difference is that in step S20, the amount of glycolic acid added is 19 g.

[0060] It was measured that the yield of the modified titanate catalyst prepared in this example was 91.46%.

[0061] Example 4

[0062] This embodiment is based on Embodiment 1, and the difference is that in step S20, the amount of glycolic acid added is 20 g.

[0063] It was measured that the yield of the modified titanate catalyst prepared in this example was 91.43%.

[0064] Example 5

[0065] This embodiment is based on the embodiment 3, and the difference is that in step S20, glycolic acid is added at a feeding rate of 3.8 g / min, and the rest is the same as the embodiment 3.

[0066] It was measured that the yield of the modified titanate catalyst prepared in this example was 92.82%.

[0067] Comparative Example 1

[0068] In this comparative example, tetrabutyl titanate in step S10 is used as a catalyst.

[0069] Comparative Example 2

[0070] This comparative example is based on Example 1, with the difference that step S20 is not included, that is, in step S30, the titanate acetylacetonate complex prepared in step S10 is cooled to room temperature (25°C), and the volatile components are removed by reduced pressure distillation to prepare a catalyst, and the rest is the same as Example 1.

[0071] Application Examples 1 to 5 and Comparative Application Examples 1 to 2

[0072] The catalysts prepared in Examples 1 to 5 and Comparative Examples 1 to 2 were used to prepare polyphenylene sulfide, corresponding to Application Examples 1 to 5 and Application Comparative Examples 1 to 2.

[0073] Specifically, the preparation process of polyphenylene sulfide includes the following steps:

[0074] (1) providing a 10L reactor, adding 1kg of phenol (C6H5OH, purity 99.5%), 30g of phosphoric acid (H3PO4, purity 99%) and 10g of a catalyst to the reactor under a nitrogen atmosphere, controlling the temperature of the mixed solution in the reactor to be 160°C, stirring at a stirring rate of 100rpm, introducing hydrogen sulfide from the bottom of the reactor at a flow rate of 2L / min, so that the hydrogen sulfide contacts the mixed solution in the reactor, stirring and reacting for 4h, and obtaining phenyl disulfide, wherein the water generated during the reaction is gasified into water vapor, and the water vapor is discharged together with the overflowing hydrogen sulfide gas from the exhaust pipe at the top of the reactor (the temperature in the exhaust pipe is controlled at 100-120°C) to ensure the progress of the reaction;

[0075] (2) maintaining a nitrogen protective atmosphere, controlling the temperature of the mixed solution in the reactor to 240° C., maintaining a stirring rate of 100 rpm, adding 1.5 kg of cyclopentane sulfone (C4H8O2S, purity 99%) and 50 g of a catalyst, stirring and reacting for 6 h to obtain a polyphenylene sulfide solution;

[0076] (3) The polyphenylene sulfide solution obtained in step (2) is filtered to separate the solid from the liquid to obtain a solid, and the solid is washed with methanol for three times, crushed and dried to obtain polyphenylene sulfide with an average particle size of 2 mm.

[0077] The catalysts in step (1) and step (2) correspond to the catalysts prepared in Examples 1 to 5 and Comparative Examples 1 to 2.

[0078] It was measured that the yield of polyphenylene sulfide prepared in Application Examples 1 to 5 was greater than 90%, and the purity was greater than 99.9%, while the yield of polyphenylene sulfide prepared in Comparative Examples 1 to 2 was less than 82%, and the purity was less than 90%.

[0079] The above are only preferred embodiments of the present application, and do not limit the scope of the present application. For those skilled in the art, the present application may have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the scope of the patent protection of the present application.

Claims

1. A process for preparing a modified titanate catalyst, characterized in that: The following steps are involved: S10, under a protective atmosphere, adding tetrabutyl titanate into a reaction container, controlling the temperature of the solution in the reaction container to 60-80° C., stirring, adding acetylacetone, and obtaining a titanate acetylacetone complex after reaction; S20, controlling the temperature of the solution in the reaction container to 80-90° C., maintaining stirring, adding glycolic acid, and obtaining a modified titanate catalyst solution after reaction; S30, cooling the modified titanate catalyst solution obtained in step S20 to room temperature, removing volatile components by reduced pressure distillation, and obtaining a powdered modified titanate catalyst.

2. The preparation process of the modified titanate catalyst according to claim 1, characterized in that: The mass ratio of tetrabutyl titanate and acetylacetone in step S10 and the hydroxyacetic acid in step S20 is (80-90):(46-55):(17-20).

3. The preparation process of the modified titanate catalyst according to claim 2, characterized in that: The mass ratio of the tetrabutyl titanate, the acetylacetone, and the glycolic acid is 85:50:

19.

4. The preparation process of the modified titanate catalyst according to claim 1, characterized in that: In the step S20, glycolic acid is added to the titanate acetylacetonate complex at a feeding rate of 3 to 5 g / min.

5. The process for preparing the modified titanate catalyst according to claim 4, characterized in that: In the step S20, glycolic acid is added to the titanate acetylacetonate complex at a feeding rate of 3.8 g / min.

6. The process for preparing the modified titanate catalyst according to claim 1, characterized in that: In the step S10, the protective atmosphere is nitrogen; and / or, In the step S10, the stirring time is 1 to 2 hours; and / or, In the step S20, the stirring time is 2 to 3 hours.

7. A modified titanate catalyst, characterized in that: The modified titanate catalyst is prepared by the preparation process of any one of claims 1 to 6.

8. Use of the modified titanate catalyst as claimed in claim 7 in the preparation of polyphenylene sulfide.