Antimony flame retardant and preparation method thereof

Abstract

The invention relates to the field of flame retardants, in particular to an antimony flame retardant and a preparation method thereof, and the antimony flame retardant is composed of antimony oxychloride and a triazinyl derivative; the preparation method of antimony oxychloride comprises the following steps: grinding stibnite, washing with deionized water, drying to obtain powder, adding the powder into the deionized water, uniformly stirring and mixing, introducing chlorine, sealing, heating to 120-140 DEG C, keeping the temperature, stirring and reacting for 10-20 hours, collecting a crude product after the reaction is finished, washing the crude product with the deionized water, and drying to obtain the antimony oxychloride. And purifying in carbon disulfide to obtain antimony oxychloride. The antimony flame retardant provided by the invention can greatly improve the flame retardant property of a plastic product.

Description

Technical Field

[0001] The invention relates to the field of flame retardants, in particular to an antimony-based flame retardant and a preparation method thereof. Background Art

[0002] Synthetic polymer materials such as synthetic fibers, plastics, and rubber are increasingly widely used in transportation, furniture, interior decoration, building materials, electronic appliances, and other fields, playing an important role in production and life. However, polymer materials are generally flammable or combustible, and are prone to fire accidents, which has become a social issue of general concern.

[0003] In order to solve the flammability problem of synthetic materials and ensure the safety of synthetic materials, the most effective method is to add flame retardants. Antimony oxychloride is widely used as a flame retardant with good performance. At present, antimony oxychloride is mostly prepared by hydrolyzing antimony trichloride. Although this method is simple and easy, the raw material antimony trichloride is expensive and the hydrolysis process is difficult to control. How to reduce the production cost of antimony oxychloride, reduce the process difficulty, and improve its flame retardant properties has become an urgent problem to be solved. Summary of the invention

[0004] Purpose of the invention: In view of the above technical problems, the present invention proposes an antimony-based flame retardant and a preparation method thereof.

[0005] The technical solutions adopted are as follows: An antimony-based flame retardant, composed of antimony oxychloride and a triazine derivative; The preparation method of the antimony oxychloride is as follows: The stibnite is ground, washed with deionized water and dried to obtain a powder, the powder is added to deionized water, stirred and mixed, chlorine is introduced, the temperature is raised to 120-140°C in a sealed state, and the reaction is carried out by stirring and heat preservation for 10-20 hours. After the reaction is completed, the crude product is collected, washed with deionized water, dried, and purified in carbon disulfide to obtain antimony oxychloride.

[0006] Furthermore, the mass ratio of the antimony oxychloride to the triazine derivative is 1:0.1-0.2.

[0007] Furthermore, the particle size of the powder is ≤50 μm.

[0008] Furthermore, the pressure of the introduced chlorine gas is 1-5 MPa.

[0009] Furthermore, the structural formula of the triazine derivative is as follows: .

[0010] Furthermore, the preparation method of the triazine derivative is as follows: ; Under nitrogen protection, add 2,4,6-trihydroxy-1,3,5-triazine, tri(3,5-dibromophenyl)phosphine oxide and dimethyl sulfoxide into a flask, stir and heat to 110-130°C, add sodium hydroxide, continue to react for 1-5 hours, reduce pressure and concentrate the reaction solution, cool to room temperature, add dichloromethane and deionized water, stir well, separate the dichloromethane phase, dry with anhydrous sodium sulfate and concentrate under reduced pressure.

[0011] Furthermore, the molar ratio of the 2,4,6-trihydroxy-1,3,5-triazine to tris(3,5-dibromophenyl)phosphine oxide is 1:3-3.05.

[0012] Furthermore, the antimony-based flame retardant can be used as a flame retardant component in plastic products.

[0013] Furthermore, the amount of the antimony-based flame retardant is 1-5% of the mass of the plastic product.

[0014] The present invention also provides a method for preparing the antimony-based flame retardant: The triazine derivative is dissolved in an organic solvent to obtain a solution, antimony oxychloride is added to the solution and stirred sufficiently, and then the organic solvent is removed by distillation under reduced pressure.

[0015] Beneficial effects of the present invention: The invention provides an antimony flame retardant composed of antimony oxychloride and a triazine derivative, wherein the preparation process of antimony oxychloride is: Sb2S3+3Cl2+2H2O→2SbOCl+3S+4HCl, in which a mixture of antimony oxychloride and elemental sulfur is generated, and then the elemental sulfur is removed by beating and purifying with carbon disulfide to obtain antimony oxychloride. Compared with the antimony trichloride hydrolysis method, the method for preparing antimony oxychloride in the invention is simple and easy to control, and stibnite is directly used as a raw material, thereby reducing the production cost. The triazine derivative has good high temperature synthesis performance. Carbon properties can isolate the transfer of oxygen and heat. The nitrogen and phosphorus elements contained in it can release nitrogen oxides and phosphorus oxides when burned, which can suppress flames. The hydrogen bromide generated by thermal decomposition can react with antimony oxychloride to form antimony tribromide. Antimony tribromide, as a non-combustible gas with a relatively large specific gravity, can form dense smoke that covers the surface of plastic products and acts as a "wall", isolating the air to achieve the effect of extinguishing fire. Therefore, triazine derivatives and antimony oxychloride have a good synergistic flame retardant effect, which can greatly improve the flame retardant properties of plastic products. DETAILED DESCRIPTION

[0016] If the specific conditions are not specified in the examples, the experiments were carried out under conventional conditions or the conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments is not specified, they are all conventional products that can be purchased commercially. The techniques not mentioned in the present invention are all referenced to the prior art. Unless otherwise specified, the following examples and comparative examples are parallel experiments, using the same processing steps and parameters.

[0017] Embodiment 1: An antimony-based flame retardant, comprising antimony oxychloride and a triazine derivative in a mass ratio of 1:0.1. During preparation, the triazine derivative is dissolved in an appropriate amount of dichloromethane to obtain a solution, antimony oxychloride is added to the solution, the solution is stirred sufficiently, and then the dichloromethane is removed by distillation under reduced pressure. The preparation method of antimony oxychloride is as follows: After grinding the stibnite through a 400-mesh sieve, the powder was washed with deionized water and dried in an oven to obtain a powder. 100 g of the powder was added to 5000 ml of deionized water, stirred and mixed, and chlorine was introduced to a pressure of 2 MPa. The mixture was sealed and heated to 130°C. The mixture was stirred and reacted for 15 hours. After the reaction, the room temperature was restored, the chlorine was discharged and collected in an absorption bottle, the reaction solution was filtered, and the crude product was collected. The crude product was fully washed with deionized water and dried, and then added to 500 ml of carbon disulfide for pulping and purification for 30 minutes. Antimony oxychloride was obtained by filtering and drying again.

[0018] The structural formula of the triazine derivative is as follows: ; The preparation method of triazine derivatives is as follows: ; Under nitrogen protection, 500 ml of dimethyl sulfoxide was added to the flask, and then 1.29 g (10 mmol) of 2,4,6-trihydroxy-1,3,5-triazine and 22.55 g (30 mmol) of tris(3,5-dibromophenyl)phosphine oxide were added and mixed, and heated to 120 ° C with stirring, and 2 g of sodium hydroxide was added. The reaction was continued for 5 hours. The reaction solution was concentrated to about 80 ml under reduced pressure and then cooled to room temperature. 1000 ml of dichloromethane and 1000 ml of deionized water were added. After sufficient stirring, the dichloromethane phase was separated, and the phase was dried over anhydrous sodium sulfate and concentrated under reduced pressure to obtain the triazine derivative with a yield of 56.3%. ESI-MS (m / z) (M + ): Theoretical value 2141.34, measured value 2141.09.

[0019] Embodiment 2: An antimony-based flame retardant, comprising antimony oxychloride and a triazine derivative in a mass ratio of 1:0.15. During preparation, the triazine derivative is dissolved in an appropriate amount of dichloromethane to obtain a solution, antimony oxychloride is added to the solution, the solution is stirred sufficiently, and then the dichloromethane is removed by distillation under reduced pressure. The preparation method of antimony oxychloride is as follows: After grinding the stibnite through a 400-mesh sieve, the powder was washed with deionized water and dried in an oven to obtain a powder. 100 g of the powder was added to 5000 ml of deionized water, stirred and mixed, and chlorine was introduced to a pressure of 2 MPa. The mixture was sealed and heated to 130°C. The mixture was stirred and reacted for 15 hours. After the reaction, the room temperature was restored, the chlorine was discharged and collected in an absorption bottle, the reaction solution was filtered, and the crude product was collected. The crude product was fully washed with deionized water and dried, and then added to 500 ml of carbon disulfide for pulping and purification for 30 minutes. Antimony oxychloride was obtained by filtering and drying again.

[0020] The structural formula of the triazine derivative is as follows: ; The preparation method of triazine derivatives is as follows: ; Under nitrogen protection, 500 ml of dimethyl sulfoxide was added to the flask, and then 1.29 g (10 mmol) of 2,4,6-trihydroxy-1,3,5-triazine and 22.55 g (30 mmol) of tris(3,5-dibromophenyl)phosphine oxide were added and mixed, and heated to 110°C with stirring, and 2 g of sodium hydroxide was added. The reaction was continued for 5 hours. The reaction solution was concentrated to about 80 ml under reduced pressure and then cooled to room temperature. 1000 ml of dichloromethane and 1000 ml of deionized water were added. After sufficient stirring, the dichloromethane phase was separated, and the phase was dried over anhydrous sodium sulfate and concentrated under reduced pressure to obtain the triazine derivative with a yield of 54.7%. ESI-MS (m / z) (M + ): Theoretical value 2141.34, measured value 2141.22.

[0021] Embodiment 3: An antimony-based flame retardant, comprising antimony oxychloride and a triazine derivative in a mass ratio of 1:0.2. During preparation, the triazine derivative is dissolved in an appropriate amount of dichloromethane to obtain a solution, antimony oxychloride is added to the solution, the solution is stirred sufficiently, and then the dichloromethane is removed by distillation under reduced pressure. The preparation method of antimony oxychloride is as follows: After grinding the stibnite through a 400-mesh sieve, the powder was washed with deionized water and dried in an oven to obtain a powder. 100 g of the powder was added to 5000 ml of deionized water, stirred and mixed, and chlorine was introduced to a pressure of 2 MPa. The mixture was sealed and heated to 130°C. The mixture was stirred and reacted for 15 hours. After the reaction, the room temperature was restored, the chlorine was discharged and collected in an absorption bottle, the reaction solution was filtered, and the crude product was collected. The crude product was fully washed with deionized water and dried, and then added to 500 ml of carbon disulfide for pulping and purification for 30 minutes. Antimony oxychloride was obtained by filtering and drying again.

[0022] The structural formula of the triazine derivative is as follows: ; The preparation method of triazine derivatives is as follows: ; Under nitrogen protection, 500 ml of dimethyl sulfoxide was added to the flask, and then 1.29 g (10 mmol) of 2,4,6-trihydroxy-1,3,5-triazine and 22.55 g (30 mmol) of tris(3,5-dibromophenyl)phosphine oxide were added and mixed, and heated to 130 ° C with stirring, and 2 g of sodium hydroxide was added. The reaction was continued for 5 hours. The reaction solution was concentrated to about 80 ml under reduced pressure and then cooled to room temperature. 1000 ml of dichloromethane and 1000 ml of deionized water were added. After sufficient stirring, the dichloromethane phase was separated, and the phase was dried over anhydrous sodium sulfate and concentrated under reduced pressure to obtain the triazine derivative with a yield of 55.4%. ESI-MS (m / z) (M + ): Theoretical value 2141.34, measured value 2141.50.

[0023] Comparative Example 1: It is basically the same as Example 1, except that it does not contain a triazine derivative.

[0024] Comparative Example 2: The process is basically the same as Example 1, except that tris(tribromophenoxy)triazine (CAS No.: 25713-60-4) is used instead of the triazine derivative.

[0025] Comparative Example 3: The process is basically the same as Example 1, except that Trif-DOPO is used instead of the triazine derivative.

[0026] The preparation method of Trif-DOPO is as follows: ; Weigh tris-(4-formylphenoxy)-triazine (11.0 g, 25 mmol) and DOPO (21.6 g, 100 mmol), first add 100 ml of 1,2-dichloroethane into a 500 ml three-necked flask, stir and heat to 60 °C, then add the previously weighed DOPO, after DOPO is completely dissolved in 1,2-dichloroethane, slowly add tris-(4-formylphenoxy)-triazine, after adding, heat to reflux for 4 hours, after the reaction is completed, filter under reduced pressure while hot, and then use 100 ml of 1,2-dichloroethane to stir and wash the filtrate (85 °C, 30 min) twice to remove excess DOPO, and dry after washing. The yield is 69.8%.

[0027] Performance Testing: The antimony flame retardants in Examples 1-3 of the present invention and Comparative Examples 1-3 were respectively mixed uniformly with ABS resin particles, the amount of the antimony flame retardant was 1% of the total mass, and added to a twin-screw extruder for extrusion and granulation at 190-200° C. The dried particles were placed in a mold and molded by a tablet press at a molding temperature of 190-200° C. and a pressure of 5 MPa. After cooling, the samples were cut into standard sizes for testing. The blank example was a control group without adding antimony flame retardant.

[0028] The limiting oxygen index (LOI) was determined according to GB / T 2046.2-2009, and the sample size was 100 mm × 6.5 mm × 3.2 mm; The vertical combustion test was carried out with reference to GB / T 2408-2021, and the sample size was 100mm×13mm×3.2mm; Cone calorimetry (CCT) test was performed according to ISO 5660-1:2015 with a radiant power of 50 kW / m 2 , the sample size is 100mm×100mm×3.2mm.

[0029] The results of the above tests are shown in Table 1 below:

[0030] It can be seen from Table 1 above that the antimony-based flame retardant provided by the present invention can significantly improve the flame retardancy of ABS resin; From the comparison of Examples 1-3, it can be seen that the mass ratio of antimony oxychloride and triazine derivatives will affect the flame retardant performance as a flame retardant. When the mass ratio of antimony oxychloride and triazine derivatives is 1:0.15, it has the best flame retardant performance. From the comparison between Example 1 and Comparative Example 1, it can be seen that the addition of triazine derivatives can significantly improve the flame retardant properties of ABS resin; From the comparison between Example 1 and Comparative Examples 2-3, it can be seen that the synergistic flame retardant effect of antimony oxychloride and triazine derivatives is better than that of tris(tribromophenoxy)triazine and Trif-DOPO.

[0031] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An antimony-based flame retardant, characterized in that: It is composed of antimony oxychloride and triazine derivatives; The preparation method of the antimony oxychloride is as follows: The stibnite is ground, washed with deionized water and dried to obtain a powder, the powder is added to deionized water, stirred and mixed, chlorine is introduced, the temperature is raised to 120-140°C in a sealed state, and the reaction is carried out by stirring and heat preservation for 10-20 hours. After the reaction is completed, the crude product is collected, washed with deionized water, dried, and purified in carbon disulfide to obtain antimony oxychloride.

2. The antimony-based flame retardant according to claim 1, characterized in that The mass ratio of the antimony oxychloride to the triazine derivative is 1:0.1-0.

2.

3. The antimony-based flame retardant according to claim 1, characterized in that The particle size of the powder is ≤50 μm.

4. The antimony-based flame retardant according to claim 1, characterized in that The pressure of the chlorine gas introduced is 1-5MPa.

5. The antimony-based flame retardant according to claim 1, characterized in that: The structural formula of the triazine derivative is as follows: 。 6. The antimony-based flame retardant according to claim 5, characterized in that The preparation method of the triazine derivative is as follows: ； Under nitrogen protection, add 2,4,6-trihydroxy-1,3,5-triazine, tri(3,5-dibromophenyl)phosphine oxide and dimethyl sulfoxide into a flask, stir and heat to 110-130°C, add sodium hydroxide, continue to react for 1-5 hours, reduce pressure and concentrate the reaction solution, cool to room temperature, add dichloromethane and deionized water, stir well, separate the dichloromethane phase, dry with anhydrous sodium sulfate and concentrate under reduced pressure.

7. The antimony-based flame retardant according to claim 6, characterized in that The molar ratio of the 2,4,6-trihydroxy-1,3,5-triazine to tris(3,5-dibromophenyl)phosphine oxide is 1:3-3.

05.

8. The antimony-based flame retardant according to any one of claims 1 to 7, characterized in that The antimony-based flame retardant can be used as a flame retardant component in plastic products.

9. The antimony-based flame retardant according to claim 8, characterized in that The amount of the antimony flame retardant is 1-5% of the mass of the plastic product.

10. A method for preparing an antimony-based flame retardant as claimed in any one of claims 1 to 7, characterized in that: The triazine derivative is dissolved in an organic solvent to obtain a solution, antimony oxychloride is added to the solution and stirred sufficiently, and then the organic solvent is removed by distillation under reduced pressure.

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