Method for improving quality of bromo-triazine product based on high-shear homogenization technology

Abstract

The invention relates to the technical field of flame retardant preparation, in particular to a method for improving the quality of a bromo-triazine product based on a high-shear homogenization technology. According to the method, after a synthetic reaction of tribromophenol and a bromo-triazine product is completed, high-shear homogenization treatment is carried out on an organic solution of the tribromophenol and the bromo-triazine product, and the treatment can effectively crush coarse crystals and aggregates, so that wrapped impurities are exposed and further efficiently removed in the subsequent washing process. According to the method provided by the invention, the particle size of the product can be obviously optimized, the purity of the product is improved, and the dispersing performance of the product in a high polymer material is improved, so that a flame-retardant product with excellent performance is obtained. The method provided by the invention is simple and convenient in process, can fundamentally solve the problem of the quality pain point of the bromo-triazine product by introducing a simple and efficient high-shear homogenization treatment process, is convenient for industrial production, and has remarkable industrial application value and economic benefit.

Description

Technical Field

[0001] This invention relates to the field of flame retardant preparation technology, and in particular to a method for improving the quality of bromotriazine products based on high shear homogenization technology. Background Technology

[0002] Bromotriazine, a brominated flame retardant with high efficiency and excellent thermal stability, is widely used in the field of polymer materials. It not only has high flame retardant efficiency but also good compatibility with the substrate.

[0003] Traditional production processes for brominated triazine generally include steps such as bromination, condensation, crystallization, filtration, washing, and drying. However, in the post-processing stages of bromination and condensation, due to the complexity of the reaction system and the high viscosity of the materials, the following problems may arise: 1. Uneven material distribution: Mechanical stirring makes it difficult to precisely control the uniform dispersion of materials during the reaction process. In the subsequent crystallization stage, this can easily lead to a large number of excessively large particles in the product. Especially after the bromination reaction, tribromophenol in the oil phase is very easy to crystallize under certain conditions, and the distribution is uneven. This leads to incomplete reaction in the subsequent condensation step, resulting in excessively large particles and agglomeration in the product bromotriazine.

[0004] 2. Low product purity: Reaction byproducts, catalyst residues, or unreacted raw materials are easily encapsulated inside large particles, which has an adverse effect on product purity.

[0005] Therefore, it is of great significance to develop an efficient, simple post-processing technology that can fundamentally improve the physical properties and chemical purity of bromotriazine products. Summary of the Invention

[0006] This invention aims to at least solve one of the technical problems existing in related technologies. Therefore, the object of this invention is to provide a method for improving the quality of brominated triazine products based on high-shear homogenization technology.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A method for improving the quality of bromotriazine products based on high-shear homogenization technology, wherein the structural formula of the bromotriazine product is shown below: ; The synthesis of the bromotriazine product includes the following steps: S100. By reacting phenol with bromine in an organic solvent, an organic solution I containing tribromophenol is obtained. S200. After adding a reducing agent to organic solution I containing tribromophenol, high-shear homogenization is performed to obtain organic solution II containing tribromophenol. S300. Add cyanuric chloride and a phase transfer catalyst to organic solution II containing tribromophenol to react tribromophenol with cyanuric chloride to obtain organic solution I containing the bromotriazine product; S400. After adding an alkaline solution to organic solution I containing the bromotriazine product, high-shear homogenization treatment is performed to obtain organic solution II containing the bromotriazine product.

[0008] The strong shear force generated by high-shear homogenization effectively breaks down large agglomerates in the organic solution (oil phase), forming smaller, more uniformly distributed microcrystalline particles. The intense shearing also exposes impurities (such as byproducts and catalysts) encased within the crystals to the crystal surface, significantly increasing the solid-liquid contact area. This greatly improves the efficiency of subsequent washing processes, removes impurities more thoroughly, and significantly enhances product purity.

[0009] The brominated triazine product, after high-shear homogenization, is expected to achieve more uniform dispersion in downstream applications due to its high purity and uniform particle size, thereby producing high-quality flame-retardant products with stable flame retardant properties and excellent mechanical properties.

[0010] Preferably, the equipment used for high-shear homogenization is a high-shear homogenizer.

[0011] Preferably, the high-shear homogenizer operates at a speed of 5000–15000 rpm and a processing time of 15–25 min. By precisely controlling the shear rate and processing time, the final particle size distribution of the product can be actively adjusted to obtain highly uniform powder, which is beneficial for improving the dispersibility and compatibility of the product in subsequent flame-retardant plastic processing.

[0012] Preferably, the temperature control range of the high shear homogenization treatment is 70–90°C.

[0013] Preferably, in step S100, the organic solvent is selected from chlorobenzene.

[0014] Preferably, in step S200, the reducing agent is selected from sodium sulfite.

[0015] Preferably, in step S300, the phase transfer catalyst is selected from tetrabutylammonium halide.

[0016] Preferably, in step S400, the alkaline solution is selected from an aqueous sodium hydroxide solution with a concentration of 8wt% to 12wt%.

[0017] Preferably, step S400 further includes a post-treatment step of organic solution I containing the bromotriazine product and organic solution II containing the bromotriazine product: The post-treatment steps for organic solution I containing the bromotriazine product are as follows: S410. Add ethanol and deionized water to the organic solution I containing the bromotriazine product, wash, perform high-shear homogenization treatment, separate the upper aqueous phase, and obtain the organic solution II containing the bromotriazine product. The post-treatment steps for organic solution II containing the bromotriazine product are as follows: Under conditions of S420 and 15-25°C, organic solution II containing the bromotriazine product was filtered to obtain a filter cake. S430. After washing the filter cake with ethanol and deionized water, it is dried under vacuum to obtain the bromotriazine product.

[0018] Preferably, the particle size distribution range of the bromotriazine product is 4.2 μm to 4.9 μm.

[0019] The above-described one or more technical solutions in the embodiments of the present invention have at least one of the following technical effects: This invention provides a method for improving the quality of brominated triazine products based on high-shear homogenization technology. This method involves subjecting the organic solution (oil phase) to high-shear homogenization treatment after the synthesis reaction of tribromophenol and brominated triazine products. This treatment effectively breaks down coarse crystals and aggregates, exposing encapsulated impurities for efficient removal during subsequent washing.

[0020] The method provided by this invention can significantly optimize the particle size of the product, improve the product purity, and improve its dispersion performance in polymer materials, thereby obtaining flame-retardant products with excellent performance.

[0021] In summary, the method provided by this invention is simple in process. By introducing a simple and efficient high-shear homogenization process, it can fundamentally solve the pain points of bromotriazine product quality. The process flow is easy to integrate into the production line and has significant industrial application value and economic benefits.

[0022] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below in conjunction with specific embodiments. Obviously, the described embodiments are only some embodiments of this invention, not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention. The following embodiments are used to illustrate this invention, but cannot be used to limit the scope of this invention.

[0024] In the following embodiments, unless otherwise specified, the experimental methods used are conventional methods, and the materials and reagents used are commercially available, unless otherwise specified, and are carried out in accordance with the techniques or conditions described in the literature in this field or in accordance with the product instructions.

[0025] Example 1 Chlorobenzene (73.3 g) was added to a four-necked flask equipped with a stirrer, thermometer, and condenser. Then, phenol (9.6 g) and sulfuric acid (5.1 g) were added. Bromine (25.7 g) and hydrogen peroxide (20.2 g) were slowly added dropwise. The mixture was reacted at 80 °C for 2 h. After the reaction was completed, the upper aqueous phase was separated. A 5 wt% sodium sulfite aqueous solution (25 g) was added to the oil phase containing tribromophenol. The mixture was then transferred to a container equipped with a high-shear homogenizer. The oil phase was subjected to high-shear treatment at 5000 rpm for 20 min. The upper aqueous phase was separated again to obtain the treated tribromophenol-containing oil phase.

[0026] Add cyanuric chloride (6.1 g) and tetrabutylammonium bromide (0.3 g) to the treated tribromophenol-containing oil phase and mix thoroughly. Add 10 wt% sodium hydroxide aqueous solution at 15 °C until the material is weakly alkaline and then stop adding. Heat the material to reflux and keep it at that temperature for 2 h. After the reaction is complete, separate the upper aqueous phase and transfer the oil phase to a container equipped with a high-shear homogenizer. Add an appropriate amount of ethanol and deionized water and shear the oil phase at 5000 rpm for 20 min. Separate the upper aqueous phase to obtain the oil phase containing the bromotriazine product.

[0027] The oil phase containing the brominated triazine product was cooled to room temperature and filtered. The filter cake was washed multiple times with appropriate amounts of ethanol and deionized water. Finally, the filter cake was vacuum dried at 100°C for 12 hours to obtain a white powdered brominated triazine product with a melting point of 229–231°C, a yield of 96.6%, a purity of 99.4% (determined by high performance liquid chromatography), and a D50 of 4.9 μm (determined by Malvern laser particle size analyzer).

[0028] Example 2 Chlorobenzene (73.3 g) was added to a four-necked flask equipped with a stirrer, thermometer, and condenser. Then, phenol (9.6 g) and sulfuric acid (5.1 g) were added. Bromine (25.7 g) and hydrogen peroxide (20.2 g) were slowly added dropwise. The mixture was reacted at 80 °C for 2 h. After the reaction was completed, the upper aqueous phase was separated. A 5 wt% sodium sulfite aqueous solution (25 g) was added to the oil phase containing tribromophenol. The mixture was then transferred to a container equipped with a high-shear homogenizer. The oil phase was subjected to high-shear treatment at 10,000 rpm for 20 min. The upper aqueous phase was separated again to obtain the treated tribromophenol-containing oil phase.

[0029] Add cyanuric chloride (6.1 g) and tetrabutylammonium bromide (0.3 g) to the treated tribromophenol-containing oil phase and mix thoroughly. Add 10 wt% sodium hydroxide aqueous solution at 15 °C until the material becomes weakly alkaline and then stop adding. Heat the material to reflux and keep it at that temperature for 2 h. After the reaction is complete, separate the upper aqueous phase and transfer the oil phase to a container equipped with a high-shear homogenizer. Add an appropriate amount of ethanol and deionized water and shear the oil phase at 10,000 rpm for 20 min. Separate the upper aqueous phase to obtain the oil phase containing the bromotriazine product.

[0030] The oil phase containing the bromotriazine product was cooled to room temperature and filtered. The filter cake was washed multiple times with appropriate amounts of ethanol and deionized water. Finally, the filter cake was vacuum dried at 100°C for 12 hours to obtain a white powdery bromotriazine product with a melting point of 229–230°C, a yield of 97.1%, a purity of 99.3% (determined by high performance liquid chromatography), and a D50 of 4.2 μm (determined by Malvern laser particle size analyzer).

[0031] Example 3 Chlorobenzene (73.3 g) was added to a four-necked flask equipped with a stirrer, thermometer, and condenser. Then, phenol (9.6 g) and sulfuric acid (5.1 g) were added. Bromine (25.7 g) and hydrogen peroxide (20.2 g) were slowly added dropwise. The mixture was reacted at 80 °C for 2 h. After the reaction was completed, the upper aqueous phase was separated. A 5 wt% sodium sulfite aqueous solution (25 g) was added to the oil phase containing tribromophenol. The mixture was then transferred to a container equipped with a high-shear homogenizer. The oil phase was subjected to high-shear treatment at 15,000 rpm for 20 min. The upper aqueous phase was separated again to obtain the treated tribromophenol-containing oil phase.

[0032] Add cyanuric chloride (6.1 g) and tetrabutylammonium bromide (0.3 g) to the treated tribromophenol-containing oil phase and mix thoroughly. Add 10 wt% sodium hydroxide aqueous solution at 15 °C until the material is weakly alkaline and then stop adding. Heat the material to reflux and keep it at that temperature for 2 h. After the reaction is complete, separate the upper aqueous phase and transfer the oil phase to a container equipped with a high-shear homogenizer. Add an appropriate amount of ethanol and deionized water and shear the oil phase at 15000 rpm for 20 min. Separate the upper aqueous phase to obtain the oil phase containing the bromotriazine product.

[0033] The oil phase containing the brominated triazine product was cooled to room temperature and filtered. The filter cake was washed multiple times with appropriate amounts of ethanol and deionized water. Finally, the filter cake was vacuum dried at 100°C for 12 hours to obtain a white powdered brominated triazine product with a melting point of 228–231°C, a yield of 96.5%, a purity of 99.6% (determined by high performance liquid chromatography), and a D50 of 4.5 μm (determined by Malvern laser particle size analyzer).

[0034] Comparative Example The same reaction materials and synthesis conditions as in Example 1 were used, except that high-shear homogenization was not performed, as detailed below: Chlorobenzene (73.3 g) was added to a four-necked flask equipped with a stirrer, thermometer, and condenser. Then, phenol (9.6 g) and sulfuric acid (5.1 g) were added. Bromine (25.7 g) and hydrogen peroxide (20.2 g) were slowly added dropwise. The reaction was carried out at 80 °C for 2 h. After the reaction was completed, the upper aqueous phase was separated. 5 wt% sodium sulfite aqueous solution (25 g) was added to the oil phase containing tribromophenol. Then, cyanuric chloride (6.1 g) and tetrabutylammonium bromide (0.3 g) were added to the oil phase and mixed thoroughly. 10 wt% sodium hydroxide aqueous solution was added at 15 °C until the material was weakly alkaline. The addition was stopped. The material was heated to reflux and kept at this temperature for 2 h. The upper aqueous phase was separated. The mixture was washed with an appropriate amount of ethanol and deionized water. The upper aqueous phase was separated again. The oil phase was cooled to room temperature and filtered. The filter cake was washed multiple times with an appropriate amount of ethanol and deionized water. Finally, the filter cake was vacuum dried at 100℃ for 12h to obtain a white powder product, bromotriazine, with a melting range of 228-230℃, a yield of 95.9%, a purity of 97.8% (determined by high performance liquid chromatography), and a D50 of 5.5μm (determined by Malvern laser particle size analyzer).

[0035] As can be seen from the data provided in the above embodiments and comparative examples, the present invention significantly optimizes the particle size distribution, particle morphology and chemical purity of bromotriazine products by means of high shear homogenization treatment, which can greatly improve their application performance. The process is simple, feasible and effective.

[0036] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for improving the quality of bromotriazine products based on high-shear homogenization technology, characterized in that, The structural formula of the bromotriazine product is shown below: ； The synthesis of the bromotriazine product includes the following steps: S100. By reacting phenol with bromine in an organic solvent, an organic solution I containing tribromophenol is obtained. S200. After adding a reducing agent to organic solution I containing tribromophenol, high-shear homogenization is performed to obtain organic solution II containing tribromophenol. S300. Add cyanuric chloride and a phase transfer catalyst to organic solution II containing tribromophenol to react tribromophenol with cyanuric chloride to obtain organic solution I containing the bromotriazine product; S400. After adding an alkaline solution to organic solution I containing the bromotriazine product, high-shear homogenization treatment is performed to obtain organic solution II containing the bromotriazine product.

2. The method for improving the quality of bromotriazine products based on high-shear homogenization technology as described in claim 1, characterized in that, The equipment used for high-shear homogenization is a high-shear homogenizer.

3. The method for improving the quality of bromotriazine products based on high-shear homogenization technology as described in claim 2, characterized in that, The high-shear homogenizer operates at a speed of 5000–15000 rpm and has a processing time of 15–25 min.

4. The method for improving the quality of bromotriazine products based on high-shear homogenization technology as described in claim 1, characterized in that, The temperature control range for the high-shear homogenization treatment is 70–90°C.

5. The method for improving the quality of bromotriazine products based on high-shear homogenization technology as described in claim 1, characterized in that, In step S100, the organic solvent is selected from chlorobenzene.

6. The method for improving the quality of bromotriazine products based on high-shear homogenization technology as described in claim 1, characterized in that, In step S200, the reducing agent is selected from sodium sulfite.

7. The method for improving the quality of bromotriazine products based on high-shear homogenization technology as described in claim 1, characterized in that, In step S300, the phase transfer catalyst is selected from tetrabutylammonium halide.

8. The method for improving the quality of bromotriazine products based on high-shear homogenization technology as described in claim 1, characterized in that, In step S400, the alkaline solution is selected from an aqueous sodium hydroxide solution with a concentration of 8wt% to 12wt%.

9. The method for improving the quality of bromotriazine products based on high-shear homogenization technology as described in claim 1, characterized in that, Step S400 further includes a post-treatment step of organic solution I containing the bromotriazine product and organic solution II containing the bromotriazine product: The post-treatment steps for organic solution I containing the bromotriazine product are as follows: S410. Add ethanol and deionized water to the organic solution I containing the bromotriazine product, wash, perform high-shear homogenization treatment, separate the upper aqueous phase, and obtain the organic solution II containing the bromotriazine product. The post-treatment steps for organic solution II containing the bromotriazine product are as follows: Under conditions of S420 and 15-25°C, organic solution II containing the bromotriazine product was filtered to obtain a filter cake. S430. After washing the filter cake with ethanol and deionized water, it is dried under vacuum to obtain the bromotriazine product.

10. The method for improving the quality of bromotriazine products based on high-shear homogenization technology as described in claim 9, characterized in that, The particle size distribution range of the bromotriazine product is 4.2 μm to 4.9 μm.

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