WO2021238146A1

WO2021238146A1 - Flame-retardant high-impact polystyrene composite material and preparation method therefor

Info

Publication number: WO2021238146A1
Application number: PCT/CN2020/135106
Authority: WO
Inventors: 潘勇; 贾志猛; 石祥辉; 冯鑫; 蒋军成
Original assignee: 南京工业大学
Priority date: 2020-05-26
Filing date: 2020-12-10
Publication date: 2021-12-02
Also published as: CN111518355B; LU500268B1; CN111518355A

Abstract

A flame-retardant high-impact polystyrene composite material and a preparation method therefor, the following components thereof and the parts by mass of each component being: 85 parts of high-impact polystyrene, 3-15 parts of a modified phosphorus-based flame retardant and 3-15 parts of a nano flame retardant, wherein the modified phosphorus-based flame retardant is a silane coupling agent modified phosphorus-based flame retardant, and the mass ratio of the silane coupling agent to the phosphorus-based flame retardant is (2-7):100. The phosphorus-containing flame retardant and the nano flame retardant have a synergistic effect in terms of flame retardant effect, so that the flame retardant property of the composite flame retardant may be improved, and the flame retardant property of the high-impact polystyrene composite material is enhanced. The present invention has a simple process flow, has extensive raw material sources, is non-toxic and harmless, is environment-friendly, and has good application prospects.

Description

[Name of invention formulated by ISA according to Rule 37.2] 　Flame-retardant high-impact polystyrene composite material and its preparation method

Technical field

The invention relates to the technical field of polymer flame-retardant materials, in particular to a flame-retardant high-impact polystyrene composite material and a preparation method thereof.

Background technique

High-impact polystyrene is a typical rubber-toughened resin material. It has the advantages of rigidity, good processability, easy coloring, and dimensional stability. It is widely used in industry, agriculture, national defense, science and technology and other fields. However, the flammability of high-impact polystyrene limits its scope of application. Therefore, increasing commercial demand has prompted people to develop effective and environmentally friendly flame retardants to enhance the fire-retardant properties of high-impact polystyrene.

At present, a variety of flame-retardant methods such as fire-retardant coating technology, flame-retardant filler technology, flame-retardant solution immersion and chemical graft flame-retardant technology are applied to polymer composites to improve their flame-retardant properties. Among them, flame-retardant filler technology With its low cost and excellent performance, it has become one of the most commonly used technologies. In the research process of flame-retardant polymer composites, two or more fillers are added to the polymer matrix together, and the study of their synergistic effect has paid more and more attention to the flame-retardant properties of polymer composites, which is important for finding suitable Flame retardants, optimizing the formulation of flame retardants to improve the performance and scope of application of polymer composites are very meaningful.

Summary of the invention

The purpose of the present invention is to overcome the performance defects of existing products, and to provide a flame-retardant high-impact polystyrene composite material. Another object of the present invention is to provide the above-mentioned flame-retardant high-impact polystyrene Composite material preparation method.

To achieve this objective, the specific technical scheme of the present invention is as follows: a flame-retardant high-impact polystyrene composite material, which is characterized in that its components and the mass parts of each component are respectively: high-impact polystyrene 85 Parts, modified phosphorus flame retardant 3-15 parts, nano flame retardant 3-15 parts; wherein the modified phosphorus flame retardant is a phosphorus flame retardant modified by a silane coupling agent, silane coupling The mass ratio of agent to phosphorus flame retardant is (2-7):100.

Preferably, the phosphorus flame retardant is any one of ammonium polyphosphate, red phosphorus or ammonium dihydrogen phosphate; the nano flame retardant is any one of carbon nanotubes, graphene or graphene oxide ; The coupling agent is any one of Si-171, KH-550 or KH-560.

The present invention also provides a method for preparing the above-mentioned flame-retardant high-impact polystyrene composite material, and the specific steps are as follows:

(1) After adding the silane coupling agent to the organic solvent and stirring uniformly, continue to heat under stirring to obtain solution A;

(2) Add the phosphorus-based flame retardant to the organic solvent and stir evenly to obtain solution B;

(3) Add solution B to solution A and heat under stirring to obtain solution C;

(4) Filtering, drying, and grinding solution C to obtain modified phosphorus flame retardant D;

(5) Add high-impact polystyrene, modified phosphorus flame retardant D and nano flame retardant to the torque rheometer for blending, and then put them in a flat vulcanizer for processing.

Preferably, the organic solvents in steps (1) and (2) are absolute ethanol.

Preferably, the stirring speed in steps (1)-(4) is 300-500 r/min.

Preferably, in step (1), the silane coupling agent is added to the organic solvent and the stirring time is 8-13 min; the heating temperature in the stirring state is 80-90° C., and the heating time is 50-70 min.

Preferably, the stirring time described in step (2) is 25-35 min.

Preferably, the heating temperature in step (3) is 45-55°C, and the heating time is 110-130 min.

Preferably, the drying temperature in step (4) is 80-100° C., and the time is 3.5-5 h, and it is passed through a 300-mesh sieve after grinding.

Preferably, the parameters of the torque rheometer described in step (5) are: the temperature is 175-190°C, the mixing time is 15-25min, and the rotation speed is 40-60r/min; the parameters of the plate vulcanizer are: warm-up time The temperature of the upper and lower plates of the hot pressing is 175-190℃, the pressure is 9-11Mpa, and the hot pressing time is 4-6min; the temperature of the upper and lower plates of the cold pressing is 20-30℃, and the pressure is 9-11Mpa, cold The pressing time is 4-6min.

Beneficial effects:

The modified phosphorus-based flame retardant provided by the present invention solves the problem of poor compatibility between the phosphorus-based flame retardant and the high-impact polystyrene to a certain extent, and improves the thermal stability. After the modified phosphorus flame retardant is compounded with the nano flame retardant, the nano flame retardant makes up for the disadvantage that the modified phosphorus flame retardant does not contain carbon elements and cannot form a carbon layer during the combustion process. In addition, the modified phosphorus flame retardant provided by the present invention has a synergistic effect with the nano flame retardant, so that the flame retardant high impact polystyrene composite material provided by the present invention reduces the peak heat release rate and increases the residual rate. The amount of carbon, the flame retardant performance is better.

Description of the drawings

Figure 1 shows the high-impact polystyrene, high-impact polystyrene/modified ammonium polyphosphate, and high-impact polystyrene provided by Comparative Examples 1, 2, 3 and Examples 1, 2, 3, 4, and 5 of the present invention. Comparison chart of heat release rate of styrene/graphene and high-impact polystyrene/modified ammonium polyphosphate/graphene composite materials.

Figure 2 shows the high-impact polystyrene, high-impact polystyrene/modified ammonium polyphosphate, and high-impact polystyrene provided by Comparative Examples 1, 2, 3 and Examples 1, 2, 3, 4, and 5 of the present invention. Comparison chart of total heat release curves of styrene/graphene and high-impact polystyrene/modified ammonium polyphosphate/graphene composite materials.

Figure 3 is the thermogravimetric (TG and DTG) curves of modified ammonium polyphosphate and pure ammonium polyphosphate provided in Comparative Example 2 under nitrogen atmosphere.

4 is a scanning electron microscope (SEM) image of ammonium polyphosphate and modified ammonium polyphosphate particles provided in Comparative Example 2.

Detailed ways

In order to facilitate the understanding of the present invention, the present invention will be described in detail below in conjunction with the accompanying drawings and embodiments of the specification, but the protection scope of the present invention is not limited to the following specific embodiments.

Unless otherwise defined, all professional terms used in the following have the same meaning as commonly understood by those skilled in the art. The terminology used herein is only for the purpose of describing specific embodiments, and is not intended to limit the protection scope of the present invention.

Unless otherwise specified, the various reagents and raw materials used in the present invention are all commercially available products or products that can be prepared by known methods.

The technical scheme adopted by the invention will be further explained below in conjunction with the drawings and embodiments.

Comparative example 1

1. Preparation of pure high impact polystyrene material

Add high-impact polystyrene resin to the torque rheometer, adjust the temperature to 180°C, control the speed to 50r/min, mix it in the torque rheometer for 20 minutes, make it evenly mixed, and put it in the coated PET In the metal mold of the film, preheat it on a plate vulcanizer (the temperature of the upper and lower plates are both set to 180°C) for 10 minutes, then hot press at 10MPa for 5 minutes, then cold press at 25°C and 10MPa for 5 minutes, and then demold. Pure high-impact polystyrene. The heat release rate and total heat release curves are shown in Figures 1 and 2 respectively; the specific data of the peak heat release rate, the total heat release and the amount of residual carbon are shown in Table 1.

Refer to Figures 1, 2 and Table 1 that the peak heat release rate of pure high-impact polystyrene is 1450.1kW/m ² , the total heat release is 158.3MJ/m ² , and the amount of carbon residue is 0%, indicating that the pure high-impact polystyrene The punched polystyrene burns completely in the cone calorimeter combustion test.

Table 1 Cone calorimetric test data of each comparative example and embodiment (50kW/m ² )

Comparative example 2

1. Preparation of high impact polystyrene/modified ammonium polyphosphate composite material

1.5 g of silane coupling agent Si-171 was added to 50 mL of absolute ethanol and stirred for 10 min. The stirred solution was heated to 85° C. and stirred for 60 min to obtain solution A.

Disperse 50 g of ammonium polyphosphate in 200 mL of absolute ethanol, and fully stir for 30 minutes to make it evenly dispersed to obtain solution B. Then, solution B was added to solution A, keeping the temperature of the reaction system at 50°C, and fully reacting for 120 minutes under stirring to obtain product C. Finally, the product C is suction filtered, dried in a vacuum drying oven at 80° C. for 4 hours, and then ground and crushed through a 300-mesh sieve to obtain a modified product D.

Add modified product D and high-impact polystyrene into the torque rheometer at a ratio of 15:85, adjust the roller temperature at 185°C, control the speed at 45r/min, and mix in the torque rheometer 22min, make it evenly mixed, put it into a metal mold covered with PET film, preheat it on a plate vulcanizer (both the upper and lower plates temperature are 190℃) for 11min, then heat press at 9MPa for 6min, and then at 20℃, 11MPa conditions It is cold pressed for 4 minutes, and then demolded to obtain a high-impact polystyrene/modified ammonium polyphosphate composite material. The heat release rate and total heat release curves are shown in Figures 1 and 2 respectively; the specific data of the peak heat release rate, the total heat release and the amount of residual carbon are shown in Table 1.

Referring to Figures 1, 2 and Table 1, it can be seen that the addition of modified ammonium polyphosphate significantly reduces the peak heat release rate of the high-impact polystyrene. Peak heat release rate of the Comparative Example 1 was obtained 1450.1kW / m ^2, the total heat release was 158.3MJ / m ^2, and the peak heat release rate of the Comparative Example 2 was obtained 840.7kW / m ^2, the total heat release 146.5 MJ/m ² . In addition, the peak heat release rate of this comparative example is relatively low and wide, and the amount of carbon residue also increased from 0% to 10.84%.

Figure 3 shows the TG and DTG curves of modified ammonium polyphosphate and pure ammonium polyphosphate in a nitrogen atmosphere provided by this comparative example. Compared with ammonium polyphosphate, the thermal stability of modified ammonium polyphosphate is greatly improved, mainly due to delaying its peak temperature, reducing peak size and increasing the final residue content (from 31.08% to 36.80%).

Fig. 4 is a comparison diagram of the micro morphology of modified ammonium polyphosphate and pure ammonium polyphosphate provided by the comparative example. The pure ammonium polyphosphate sample (Figure 4a) has rough surface, unevenness, and greater hygroscopicity. After the modification treatment (Figure 4b), the particle surface is smoother and rounder, and a film is formed at the same time, indicating that the ammonium polyphosphate The particles have been coated with a film-like substance formed by the coupling agent Si-171, and the surface has changed from water absorption to water repellency, and the hygroscopicity is significantly improved.

Comparative example 3

1. Preparation of high-impact polystyrene/graphene composite materials

1.5 g of silane coupling agent Si-171 was added to 50 mL of absolute ethanol and stirred for 9 min. The stirred solution was heated to 80° C. and stirred for 70 min to obtain solution A.

Disperse 50 g of ammonium polyphosphate in 200 mL of absolute ethanol, fully stir to make it uniformly dispersed, and the stirring time is 35 minutes to obtain solution B. Then solution B was added to solution A, keeping the temperature of the reaction system at 55°C, and fully reacting for 110 minutes under stirring to obtain product C. Finally, the product C is suction filtered, dried in a vacuum drying oven at 100° C. for 3.5 hours, ground and crushed, and then passed through a 300-mesh sieve to obtain a modified product D.

Add high-impact polystyrene and graphene to the torque rheometer at a ratio of 85:15, adjust the roller temperature at 175°C, control the speed at 60r/min, and mix in the torque rheometer for 20 minutes. Make it evenly mixed and put it into a metal mold covered with PET film, preheat it on a plate vulcanizer (the temperature of the upper and lower plates are both set to 175℃) for 9min, then hot press at 11Mpa for 6min, and then at 30℃, 11MPa Under the conditions of cold pressing for 5 minutes, and then demolding, a high-impact polystyrene/graphene composite material is obtained. The heat release rate and total heat release curves are shown in Figures 1 and 2 respectively; the specific data of the peak heat release rate, total heat release and carbon residue content are shown in Table 1.

Referring to Figures 1, 2 and Table 1, it can be seen that after only adding graphene, although the peak heat release rate of the composite material reaches the lowest, the total heat release is the highest, and the amount of carbon residue is also low, indicating that graphene is highly resistant to reduction. The peak heat release rate of impact polystyrene has a significant effect, but the reduction of the total heat release has a limited effect on the increase of the amount of carbon residue.

Example 1

1. Preparation of high impact polystyrene/modified ammonium polyphosphate/graphene composite material (12:85:3)

1.5 g of silane coupling agent Si-171 was added to 50 mL of absolute ethanol and stirred for 11 min. The stirred solution was heated to 90° C. and stirred for 55 min to obtain solution A.

Disperse 50 g of ammonium polyphosphate in 200 mL of absolute ethanol, fully stir to make it uniformly dispersed, and the stirring time is 33 minutes to obtain solution B. Then solution B was added to solution A, keeping the temperature of the reaction system at 45°C, and fully reacting for 130 minutes under stirring to obtain product C. Finally, the product C is suction filtered, dried in a vacuum drying oven at 90° C. for 4.5 hours, ground and crushed, and then passed through a 300-mesh sieve to obtain a modified product D (all the above stirring rates are 500 r/min).

Add modified product D, high-impact polystyrene and graphene into the torque rheometer at a ratio of 12:85:3, adjust the roller temperature at 190℃, and control the speed at 40r/min. Mix it in the instrument for 25 minutes, make it evenly mixed, and put it into a metal mold covered with PET film, preheat it on a plate vulcanizer (the temperature of the upper and lower plates are set to 185°C) for 10 minutes, and then heat press for 5 minutes at 10Mpa , And then cold pressed for 6 minutes at 23° C. and 9 MPa, and then demolded to obtain a high-impact polystyrene/modified ammonium polyphosphate/graphene composite material. The heat release rate and total heat release curves are shown in Figures 1 and 2 respectively; the specific data of the peak heat release rate, the total heat release and the amount of residual carbon are shown in Table 1.

Referring to Figures 1, 2 and Table 1, it can be seen that after the modified ammonium polyphosphate and graphene are added together, the total heat release of Example 1 is significantly lower than that of Comparative Example 1, Comparative Example 2 and Comparative Example 3, and the heat release rate is The peak value is lower than that of Comparative Example 1 and Comparative Example 2, and the amount of residual carbon is slightly lower than that of Comparative Example 2, indicating that the modified ammonium polyphosphate plays a major role in the process of promoting the carbon formation of the polymer.

Table 2 shows the calculated value of the heat release rate peak synergistic effect index of each example. It can be found that the synergy index of the peak heat release rate of Examples 1-5 is greater than 1, indicating that the modified ammonium polyphosphate/graphene system has a synergistic effect in the high-impact polystyrene matrix, and the flame retardant added by the two The effect is better than the effect of adding each component separately.

Example 2

1. Preparation of high impact polystyrene/modified ammonium polyphosphate/graphene composite material (9:85:6)

1.5 g of silane coupling agent Si-171 was added to 50 mL of absolute ethanol and stirred for 13 min. The stirred solution was heated to 90° C. and stirred for 50 min to obtain solution A.

Disperse 50 g of ammonium polyphosphate in 200 mL of absolute ethanol, fully stir to make it uniformly dispersed, and the stirring time is 28 minutes to obtain solution B. Then solution B was added to solution A, keeping the temperature of the reaction system at 50°C, and fully reacting for 115 minutes under stirring to obtain product C. Finally, the product C is suction filtered, dried in a vacuum drying oven at 85° C. for 5 hours, ground and crushed, and then passed through a 300-mesh sieve to obtain a modified product D (the above stirring rates are all 400 r/min).

Add modified product D, high-impact polystyrene and graphene into the torque rheometer at a ratio of 9:85:6, adjust the roller temperature at 180℃, and control the speed at 60r/min. Mix in the instrument for 15 minutes, make it evenly mixed, and put it into a metal mold covered with PET film, preheat it on a plate vulcanizer (the temperature of the upper and lower plates are set to 190℃) for 13 minutes, and then heat press at 11Mpa for 4 minutes , And then cold pressed for 4 minutes at 24°C and 10MPa, and then demolded to obtain a high-impact polystyrene/modified ammonium polyphosphate/graphene composite material. The heat release rate and total heat release curves are shown in Figures 1 and 2 respectively; the specific data of the peak heat release rate, the total heat release and the amount of residual carbon are shown in Table 1.

Referring to Figures 1, 2 and Table 1, it can be seen that after the modified ammonium polyphosphate and graphene are added together, as the graphene content increases, the peak heat release rate of Example 2 will be further reduced compared to Example 1. The width of the composite material is further increased, the total amount of heat release is also further reduced compared to Example 1, and the flame retardant performance of the composite material is further improved.

In addition, referring to Table 1 and Table 2, it can be seen that the peak heat release rate synergistic effect index of Example 2 is the largest, indicating that the synergistic flame retardant effect of modified ammonium polyphosphate and graphene is the best under this ratio. The total amount of heat release is the smallest, so Example 2 is a high-impact polystyrene/modified ammonium polyphosphate/graphene composite material with the best flame-retardant performance in the patent.

Example 3

1. Preparation of high impact polystyrene/modified ammonium polyphosphate/graphene composite material (7.5:85:7.5)

1.5 g of silane coupling agent Si-171 was added to 50 mL of absolute ethanol and stirred for 8 min. The stirred solution was heated to 85° C. and stirred for 65 min to obtain solution A.

Disperse 50 g of ammonium polyphosphate in 200 mL of anhydrous ethanol, fully stir to make it uniformly dispersed, and the stirring time is 34 minutes to obtain solution B. Then solution B was added to solution A, keeping the temperature of the reaction system at 55°C, and fully reacting for 125 minutes under stirring to obtain product C. Finally, the product C is suction filtered, dried in a vacuum drying cabinet at 95° C. for 4 hours, ground and crushed, and then passed through a 300-mesh sieve to obtain a modified product D (all the above stirring rates are 300 r/min).

Add modified product D, high impact polystyrene and graphene into the torque rheometer at a ratio of 7.5:85:7.5, adjust the roller temperature at 185℃, and control the speed at 40r/min. Mix it in the instrument for 23min, make it evenly mixed, put it into a metal mold covered with PET film, preheat it on a plate vulcanizer (the temperature of the upper and lower plates are set to 179℃) for 12min, and then heat press at 11Mpa for 5min , And then cold pressed for 5 minutes at 28° C. and 9 MPa, and then demolded to obtain a high-impact polystyrene/modified ammonium polyphosphate/graphene composite material. The heat release rate and total heat release curves are shown in Figures 1 and 2 respectively; the specific data of the peak heat release rate, the total heat release and the amount of residual carbon are shown in Table 1.

Referring to Figures 1, 2 and Table 1, it can be found that as the content of graphene increases, the peak heat release rate will further decrease, the width of the peak will further increase, and the amount of residual carbon will increase compared to Examples 1 and 2. This is because in the modified ammonium polyphosphate/graphene system, graphene is the main component of carbon residue. As the content of graphene increases, the amount of carbon residue gradually increases. In addition, the total heat release compared to Example 3. Example 2 increased the 10.6MJ / m ^2, this is because, as the ethylene content of the graphite, an increase in viscosity aggregated phase, hindering the intumescent flame retardant polylactic acid The expansion of ammonium, on the contrary, increases the total amount of heat released.

Example 4

1. Preparation of high impact polystyrene/modified ammonium polyphosphate/graphene composite material (6:85:9)

1.5 g of silane coupling agent Si-171 was added to 50 mL of absolute ethanol and stirred for 12 min. The stirred solution was heated to 88° C. and stirred for 62 min to obtain solution A.

Disperse 50 g of ammonium polyphosphate in 200 mL of absolute ethanol, stir thoroughly to make it uniformly dispersed, and stir for 30 minutes to obtain solution B. Then solution B was added to solution A, keeping the temperature of the reaction system at 47°C, and fully reacting for 123 minutes under stirring to obtain product C. Finally, the product C is suction filtered, dried in a vacuum drying oven at 84° C. for 3.7 hours, ground and crushed, and then passed through a 300-mesh sieve to obtain a modified product D (all the above stirring rates are 500 r/min).

Add modified product D, high impact polystyrene and graphene into the torque rheometer at a ratio of 6:85:9, adjust the roller temperature at 181℃, and control the speed at 49r/min. Mix in the instrument for 16min, make it evenly mixed, put it into a metal mold covered with PET film, preheat on a plate vulcanizer (the temperature of the upper and lower plates are set to 177℃) for 8min, and then heat press for 6min at 9Mpa , And then cold pressed at 26°C and 9MPa for 6 minutes, and then demolded to obtain a high-impact polystyrene/modified ammonium polyphosphate/graphene composite material. The heat release rate and total heat release curves are shown in Figures 1 and 2 respectively; the specific data of the peak heat release rate, the total heat release and the amount of residual carbon are shown in Table 1.

Referring to Figures 1 and 2 and Table 1, it can be seen that with the increase of the graphene content, compared with Examples 1-3, the peak heat release rate is further reduced, the width of the peak is further increased, and the amount of carbon residue is further increased. However, the increase of the graphene content increases the viscosity of the condensed phase, so that the total heat release is further increased compared to Example 4.

Example 5

1. Preparation of high impact polystyrene/modified ammonium polyphosphate/graphene composite material (3:85:12)

3.5 g of silane coupling agent Si-171 was added to 50 mL of absolute ethanol and stirred for 10 min. The stirred solution was heated to 85° C. and stirred for 58 min to obtain solution A.

Disperse 50 g of ammonium polyphosphate in 200 mL of absolute ethanol, fully stir to make it uniformly dispersed, and the stirring time is 32 minutes to obtain solution B. Then solution B was added to solution A, keeping the temperature of the reaction system at 51°C, and fully reacting for 117 minutes under stirring to obtain product C. Finally, the product C is suction filtered, dried in a vacuum drying cabinet at 93° C. for 4.2 hours, ground and crushed, and then passed through a 300-mesh sieve to obtain a modified product D (the above stirring rates are all 400 r/min).

Add modified product D, high-impact polystyrene and graphene into the torque rheometer at a ratio of 3:85:12, adjust the roller temperature at 180℃, and control the speed at 55r/min. Mix in the instrument for 18 minutes, make it evenly mixed, put it into a metal mold covered with PET film, preheat it on a plate vulcanizer (the temperature of the upper and lower plates are set to 188℃) for 10 minutes, and then heat press for 4 minutes at 9Mpa , And then cold pressed for 6 minutes at 27°C and 10MPa, and then demolded to obtain a high-impact polystyrene/modified ammonium polyphosphate/graphene composite material. The heat release rate and total heat release curves are shown in Figures 1 and 2 respectively; the specific data of the peak heat release rate, the total heat release and the amount of residual carbon are shown in Table 1.

Referring to Figures 1, 2 and Table 1, it can be seen that as the graphene content increases, the peak heat release rate will decrease to 516.2kW/m ² . The total amount of heat release of Example 5 is lower than that of Examples 3 and 4, indicating that graphene plays a major role in improving the flame retardant performance of the composite material. The dense carbon layer formed by multi-layer graphene hinders the heat transfer and the transmission of gaseous pyrolysis products. The carbon layer hinders the further progress of pyrolysis and ultimately reduces the total amount of heat released.

Equation (1) is used to calculate the synergistic effect index (SE) of the two flame retardants to evaluate whether the two components have a synergistic effect on a certain characteristic parameter of the composite material. Where x and y are the mass ratios of the two additives respectively. When the SE is greater than 1, the two flame retardants show a synergistic effect; when the SE is equal to 1, the two flame retardants show a superimposed effect; when the SE is less than 1, the two flame retardants show an antagonistic effect.

Table 2 Peak heat release rate synergy index of each embodiment

Claims

A flame-retardant high-impact polystyrene composite material, which is characterized in that its components and the mass parts of each component are respectively: 85 parts of high-impact polystyrene, and 3-15 of modified phosphorus-based flame retardants. Parts, 3-15 parts of nano flame retardant; wherein the modified phosphorus flame retardant is a phosphorus flame retardant modified by a silane coupling agent, and the mass ratio of the silane coupling agent to the phosphorus flame retardant is (2 -7):100.
The flame-retardant high-impact polystyrene composite material according to claim 1, wherein the phosphorus-based flame retardant is any one of ammonium polyphosphate, red phosphorus or ammonium dihydrogen phosphate; The nano flame retardant is any one of carbon nanotubes, graphene or graphene oxide; the coupling agent is any one of Si-171, KH-550 or KH-560.
A method for preparing the flame-retardant high-impact polystyrene composite material according to claim 1, and its specific steps are as follows:

(1) After adding the silane coupling agent to the organic solvent and stirring uniformly, continue to heat under stirring to obtain solution A;

(2) Add the phosphorus-based flame retardant to the organic solvent and stir evenly to obtain solution B;

(3) Add solution B to solution A and heat under stirring to obtain solution C;

(4) Filtering, drying, and grinding solution C to obtain modified phosphorus flame retardant D;

(5) Add high-impact polystyrene, modified phosphorus flame retardant D and nano flame retardant to the torque rheometer for blending, and then put them in a flat vulcanizer for processing.
The method according to claim 3, characterized in that the organic solvents in steps (1) and (2) are both absolute ethanol.
The method according to claim 3, wherein the stirring speed in steps (1)-(4) is 300-500 r/min.
The method according to claim 3, characterized in that in step (1), the silane coupling agent is added to the organic solvent and the stirring time is 8-13min; the heating temperature under stirring is 80-90°C, and the heating time is 50-70min.
The method according to claim 3, characterized in that the stirring time in step (2) is 25-35 min.
The method according to claim 3, wherein the heating temperature in step (3) is 45-55°C, and the heating time is 110-130 min.
The method according to claim 3, characterized in that the drying temperature in step (4) is 80-100° C., and the time is 3.5-5 h. After grinding, it is passed through a 300-mesh sieve.
The method according to claim 3, characterized in that the parameters of the torque rheometer in step (5) are: the temperature is 175-190°C, the mixing time is 15-25min, and the speed is 40-60r/min ; The parameters of the plate vulcanizing machine are: preheating time is 8-15min; the temperature of the upper and lower plates of the hot pressing is 175-190℃, the pressure is 9-11Mpa, the hot pressing time is 4-6min; the temperature of the upper and lower plates of the cold pressing is 20 -30℃, pressure is 9-11Mpa, cold pressing time is 4-6min.