An antimony-based flame retardant and its preparation method

Abstract

The present invention relates to the field of flame retardants, and specifically to an antimony-based flame retardant and a preparation method thereof, which consists of antimony oxychloride and a triazine-based derivative; the preparation method of the antimony oxychloride is as follows: stibnite is ground, washed with deionized water and dried to obtain a powder. The powder is added to deionized water, stirred and mixed evenly, then chlorine gas is introduced and sealed and heated to 120-140 °C, and the mixture is kept warm and stirred for reaction for 10-20 h. After the reaction is completed, the crude product is collected, washed with deionized water, dried, and then purified in carbon disulfide to obtain antimony oxychloride. The antimony-based flame retardant provided by the present invention can greatly improve the flame retardant performance of plastic products.

Description

Technical Field

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

[0002] Synthetic polymer materials such as synthetic fibers, plastics, and rubbers are increasingly widely used in various fields such as transportation, furniture, interior decoration, building materials, and electronic appliances, playing an important role in production and life. However, polymer materials are generally flammable or combustible, prone to causing fire accidents, and have become a common social concern.

[0003] To solve the flammability problem of synthetic materials and ensure the safety of their use, the most effective method is to add flame retardants. Antimony oxychloride is widely used as a flame retardant with good performance. Currently, antimony oxychloride is mostly prepared by hydrolyzing antimony trichloride. Although this method is simple and easy to operate, 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 performance has become an urgent problem to be solved. Summary of the Invention

[0004] Object of the Invention: Aiming at the above technical problems, the present invention proposes an antimony-based flame retardant and a preparation method thereof.

[0005] The technical solution adopted is as follows:

[0006] An antimony-based flame retardant is composed of antimony oxychloride and a triazine-based derivative;

[0007] The preparation method of the antimony oxychloride is as follows:

[0008] Stibnite is ground, washed with deionized water and dried to obtain a powder. The powder is added to deionized water, stirred and mixed evenly, then chlorine gas is introduced and sealed, and the temperature is raised to 120 - 140 °C, and the reaction is stirred and maintained for 10 - 20 h. After the reaction is completed, the crude product is collected, washed with deionized water, dried, and then purified in carbon disulfide to obtain antimony oxychloride.

[0009] Further, the mass ratio of the antimony oxychloride to the triazine-based derivative is 1:0.1 - 0.2.

[0010] Further, the particle size of the powder ≤ 50 μm.

[0011] Further, the pressure of the introduced chlorine gas is 1 - 5 MPa.

[0012] Further, the structural formula of the triazine-based derivative is as follows:

[0013] .

[0014] Furthermore, the preparation method of the triazine-based derivative is as follows:

[0015] ;

[0016] Under the condition of nitrogen protection, add 2,4,6-trihydroxy-1,3,5-triazine, tris(3,5-dibromophenyl)phosphine oxide and dimethyl sulfoxide into a flask, stir and heat to 110 - 130 °C, add sodium hydroxide, continue to keep the temperature for reaction for 1 - 5 h, concentrate the reaction solution under reduced pressure and then cool to room temperature, add dichloromethane and deionized water, separate the dichloromethane phase after sufficient stirring, and concentrate under reduced pressure after drying with anhydrous sodium sulfate.

[0017] Furthermore, the molar ratio of 2,4,6-trihydroxy-1,3,5-triazine to tris(3,5-dibromophenyl)phosphine oxide is 1:3 - 3.05.

[0018] Furthermore, the antimony-based flame retardant can be used as a flame retardant component in plastic products.

[0019] Furthermore, the dosage of the antimony-based flame retardant is 1 - 5% of the mass of the plastic product.

[0020] The present invention also provides a preparation method of the above-mentioned antimony-based flame retardant:

[0021] Dissolve the triazine-based derivative in an organic solvent to obtain a solution, add antimony oxychloride to the solution and stir well, and then distill off the organic solvent under reduced pressure.

[0022] Advantages of the present invention:

[0023] The present invention provides an antimony-based flame retardant composed of antimony oxychloride and a triazine-based derivative. The preparation process of antimony oxychloride is: Sb2S3 + 3Cl2 + 2H2O → 2SbOCl + 3S + 4HCl. In this process, a mixture of antimony oxychloride and elemental sulfur is generated, and then the elemental sulfur is removed by purification with carbon disulfide beating to obtain antimony oxychloride. Compared with the antimony trichloride hydrolysis method, the method for preparing antimony oxychloride in the present invention is simple and easy to control, and directly uses stibnite as the raw material, reducing the production cost. The triazine-based derivative has good high-temperature char-forming property, which can isolate the transfer of oxygen and heat. The nitrogen and phosphorus elements contained can release nitrogen oxides and phosphorus oxides during combustion, playing a role in suppressing the flame. The hydrogen bromide generated by thermal decomposition can react with antimony oxychloride to generate antimony tribromide. As a non-combustible gas with a relatively large specific gravity, antimony tribromide can form a dense smoke coating on the surface of the plastic product to play the role of a "wall", so as to isolate the air to achieve the effect of extinguishing fire. Therefore, there is a good synergistic flame retardant effect between the triazine-based derivative and antimony oxychloride, which can greatly improve the flame retardant performance of plastic products. Specific embodiments

[0024] 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.

[0025] Embodiment 1:

[0026] 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.

[0027] The preparation method of antimony oxychloride is as follows:

[0028] 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.

[0029] The structural formula of the triazine derivative is as follows:

[0030] ;

[0031] The preparation method of triazine derivatives is as follows:

[0032] ;

[0033] 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.

[0034] Example 2:

[0035] An antimony-based flame retardant is composed of antimony oxychloride and a triazine-based derivative with a mass ratio of 1:0.15. During preparation, the triazine-based derivative is dissolved in an appropriate amount of dichloromethane to obtain a solution, then antimony oxychloride is added to the solution and stirred thoroughly, and finally dichloromethane is removed by vacuum distillation;

[0036] The preparation method of antimony oxychloride is as follows:

[0037] After grinding stibnite through a 400-mesh sieve, it is washed with deionized water and dried in an oven to obtain a powder. Take 100 g of the powder and add it to 5000 ml of deionized water. After stirring and mixing evenly, chlorine gas is introduced until the pressure reaches 2 MPa, sealed and heated to 130 °C, and kept stirring and reacting for 15 h. After the reaction is completed, the temperature is restored to room temperature, the chlorine gas is discharged and received with an absorption bottle. The reaction solution is filtered, and the crude product is collected. The crude product is washed thoroughly with deionized water and then dried, and then added to 500 ml of carbon disulfide for pulping and purification for 30 min, and then filtered and dried again to obtain antimony oxychloride.

[0038] The structural formula of the triazine-based derivative is as follows:

[0039] ;

[0040] The preparation method of the triazine-based derivative is as follows:

[0041] ;

[0042] Under the condition of nitrogen protection, 500 ml of dimethyl sulfoxide is added to a 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 are added and mixed evenly. Stir and heat to 110 °C, add 2 g of sodium hydroxide, and continue to keep the reaction at this temperature for 5 h. The reaction solution is concentrated under reduced pressure to about 80 ml and then cooled to room temperature. Add 1000 ml of dichloromethane and 1000 ml of deionized water. After stirring thoroughly, the dichloromethane phase is separated, dried with anhydrous sodium sulfate, and then concentrated under reduced pressure to obtain the triazine-based derivative, with a yield of 54.7%, ESI-MS(m / z)(M + ): Theoretical value 2141.34, measured value 2141.22.

[0043] Example 3:

[0044] An antimony-based flame retardant is composed of antimony oxychloride and a triazine-based derivative with a mass ratio of 1:0.2. During preparation, the triazine-based derivative is dissolved in an appropriate amount of dichloromethane to obtain a solution, then antimony oxychloride is added to the solution and stirred thoroughly, and finally dichloromethane is removed by vacuum distillation;

[0045] The preparation method of antimony oxychloride is as follows:

[0046] 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.

[0047] The structural formula of the triazine derivative is as follows:

[0048] ;

[0049] The preparation method of triazine derivatives is as follows:

[0050] ;

[0051] 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.

[0052] Comparative Example 1:

[0053] It is basically the same as Example 1, except that it does not contain a triazine derivative.

[0054] Comparative Example 2:

[0055] 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.

[0056] Comparative Example 3:

[0057] The process is basically the same as Example 1, except that Trif-DOPO is used instead of the triazine derivative.

[0058] The preparation method of Trif-DOPO is as follows:

[0059] ;

[0060] 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 to a 500-ml three-necked flask, stir and heat up to 60 °C, then add the pre-weighed DOPO. After DOPO is completely dissolved in 1,2-dichloroethane, slowly add tris-(4-formylphenoxy)-triazine. After adding, heat up to reflux and react for 4 h. After the reaction is completed, perform vacuum filtration while it is hot, and then wash the filtrate with 100 ml of 1,2-dichloroethane (85 °C, 30 min) twice to remove the excess DOPO. After the washing is completed, dry it to obtain the product, and the yield is 69.8%.

[0061] Performance test:

[0062] Mix the antimony-based flame retardants in Examples 1-3 and Comparative Examples 1-3 of the present invention with ABS resin particles evenly. The dosage of the antimony-based flame retardant is 1% of the total mass. Add them to a twin-screw extruder and extrude and pelletize at 190-200 °C. Place the dried pellets in a mold and press them into shape through a tablet press. The molding temperature is 190-200 °C, and the pressure is 5 MPa. After cooling, cut them into samples of standard size for testing. The blank example is a control group without adding the antimony-based flame retardant.

[0063] The limiting oxygen index (LOI) is measured according to GB / T 2046.2-2009, and the sample size is 100 mm × 6.5 mm × 3.2 mm;

[0064] The vertical burning test is carried out according to GB / T 2408-2021, and the sample size is 100 mm × 13 mm × 3.2 mm;

[0065] The cone calorimeter test (CCT) is carried out according to ISO 5660-1:2015, and the radiation power is 50 kW / m 2 , and the sample size is 100 mm × 100 mm × 3.2 mm.

[0066] The results of the above tests are shown in Table 1 below:

[0067]

[0068] As can be seen from Table 1 above, the antimony-based flame retardant provided by the present invention can greatly improve the flame retardant performance of ABS resin;

[0069] From the comparison of Examples 1 - 3, it can be seen that the mass ratio of antimony oxychloride and triazine - based derivatives affects their flame - retardant performance as flame retardants. When the mass ratio of antimony oxychloride and triazine - based derivatives is 1:0.15, it has the best flame - retardant performance;

[0070] From the comparison of Example 1 and Comparative Example 1, it can be seen that the addition of triazine - based derivatives can significantly improve the flame - retardant performance of ABS resin;

[0071] From the comparison of Example 1 and Comparative Examples 2 - 3, it can be seen that the synergistic flame - retardant effect of antimony oxychloride and triazine - based derivatives is better than that of tris(tribromophenoxy)triazine and Trif - DOPO.

[0072] The above examples are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing examples, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing examples, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A 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 and the mixture is kept heated and stirred 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; The structural formula of the triazine derivative is as follows: 。 2. The antimony-based flame retardant according to claim 1, wherein 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 preparation method of the triazine derivative is as follows: ； Under nitrogen protection, add m1, m2 and DMSO to the 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, then 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.

6. The antimony-based flame retardant according to claim 5, wherein The molar ratio of m1 to m2 is 1:3-3.

05.

7. The antimony-based flame retardant according to any one of claims 1-6, characterized in that, The antimony-based flame retardant can be used as a flame retardant component in plastic products.

8. The antimony-based flame retardant according to claim 7, characterized in that, The amount of the antimony flame retardant is 1-5% of the mass of the plastic product.

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