Dripless flame-retardant foamed polystyrene material and method for producing the same

Abstract

The application provides a non-dripping flame-retardant foamed polystyrene material and a preparation method thereof, and belongs to the field of flame-retardant foamed polystyrene. The non-dripping flame-retardant foamed polystyrene material comprises the following raw materials: polystyrene, a bromide flame retardant, a multi-effect anti-dripping agent and a heat stabilizer. The preparation method of the non-dripping flame-retardant foamed polystyrene material comprises the following steps: a composite flame retardant containing a bromide flame retardant, a multi-effect anti-dripping agent and a heat stabilizer is prepared in an internal mixer through a melting-cooling-crushing method; and a non-dripping flame-retardant foamed polystyrene material is prepared by a double-screw extruder through the composite flame retardant, polystyrene and a foaming agent. The non-dripping flame-retardant foamed polystyrene material and the preparation method thereof can effectively improve the dripping problem of the foamed polystyrene material during combustion without affecting the foaming performance, heat preservation performance and physical performance of the foamed polystyrene material, and endow the foamed polystyrene material with excellent anti-dripping and flame-retardant performance.

Description

Technical Field

[0001] This invention relates to the field of polystyrene materials, and in particular to a non-drip flame-retardant expanded polystyrene material and its preparation method. Background Technology

[0002] Polystyrene (PS) is one of the five major general-purpose plastics. Extruded expanded polystyrene (XPS), scientifically known as extruded polystyrene foam for thermal insulation, is a rigid foam board made from polystyrene as raw material, with a foaming agent added during processing, and manufactured through extrusion and molding. XPS has a completely closed honeycomb structure with a closed-cell rate of over 99%. Its unique and uniform closed-cell structure gives expanded polystyrene extremely low thermal conductivity and apparent density, extremely low water absorption, good sound insulation performance, high mechanical strength and dimensional accuracy, etc., enabling expanded polystyrene boards to have excellent thermal insulation properties, excellent high-strength compressive strength and shock absorption, and excellent corrosion resistance and aging resistance. As a result, it can be widely used in building insulation, cold chain transportation, shipbuilding, logistics packaging and other fields, especially occupying a large proportion of commercial and civil building exterior wall insulation materials.

[0003] However, due to its low pore density, thin pore walls, and numerous carbon chains in its molecules, expanded polystyrene (EPS) is highly flammable. Furthermore, during a fire, the combustion of EPS produces large amounts of smoke and toxic gases, and it readily generates molten droplets, further spreading the fire and causing casualties. Therefore, flame retardant treatment of EPS to prepare droplet-free flame-retardant EPS, ensuring that external wall insulation materials do not burn or self-extinguish rapidly upon removal from the fire source, and preventing the spread of fire due to molten droplets, is a necessary means to improve building fire safety and is currently a key research focus for extruded EPS.

[0004] Currently, existing research on flame retardancy for expanded polystyrene (EPS) mainly focuses on the following areas: improving the flame retardant effect of methyl octabromoether (MED) on EPS; improving the flame retardant effect of brominated SBS on EPS; and research on the flame retardant effect of a composite flame retardant system of MED and brominated SBS on EPS. It can be seen that current research on flame retardancy for EPS primarily focuses on improving its flame retardant properties, without addressing the issue of dripping during melting.

[0005] The inventors discovered through research that, under normal circumstances, flame retardants such as methyl octabromoether and brominated SBS can improve the dripping phenomenon of resin materials to a certain extent. However, the unique structure of expanded polystyrene (low cell density, thin pore walls, high carbon chain content, etc.) determines that the existing flame retardant treatment methods have limited effect on improving the dripping phenomenon of expanded polystyrene during combustion.

[0006] Meanwhile, the inventors also discovered that while adding anti-dripping agents and flame retardants to expanded polystyrene (EPS) materials can improve the dripping problem to some extent, the excessive addition of anti-dripping agents significantly impacts the foaming, insulation, and physical properties of EPS materials. Specifically, this manifests as defects such as pores on the surface of EPS sheets, increased thermal conductivity, increased apparent density, and reduced material strength, severely affecting the subsequent application performance of EPS materials. Therefore, specifically addressing the severe dripping phenomenon of EPS materials during combustion to meet the increasingly stringent fire safety requirements of existing technologies is of great significance. Summary of the Invention

[0007] To address the technical problems existing in the prior art, this invention provides a non-dripping flame-retardant expanded polystyrene material and its preparation method. This method can effectively improve the dripping problem of expanded polystyrene material during combustion without affecting its foaming performance, thermal insulation performance, and physical properties, thus endowing the expanded polystyrene material with excellent anti-dripping and flame-retardant properties.

[0008] To solve the above technical problems, the technical solution adopted by the present invention is as follows: A non-dripping flame-retardant expanded polystyrene foam material, comprising the following raw materials: polystyrene, bromide flame retardant, multi-effect anti-dripping agent, and heat stabilizer; The multi-effect anti-dripping agent is at least one of the following: polytetrafluoroethylene microspheres, styrene-acrylonitrile-coated polytetrafluoroethylene, octaphenyl cage-like polysilsesquioxane, octavinyl cage-like polysilsesquioxane, nano-montmorillonite, talc, and nano-layered double hydroxide.

[0009] Furthermore, the heat stabilizer is at least one of the following: calcium stearate, zinc stearate, barium stearate, melamine, piperazine, piperazine diphosphate, or piperazine monobutyramic acid calcium / zinc.

[0010] Furthermore, the bromide flame retardant is at least one of the following: methyl octabromoether, brominated styrene-butadiene-styrene block copolymer.

[0011] Preferably, when the bromide flame retardant is methyl octabromoether and brominated styrene-butadiene-styrene block copolymer, the weight ratio of methyl octabromoether and brominated styrene-butadiene-styrene block copolymer is 0.5-1:0.5-1.

[0012] Preferably, the total weight of the bromide flame retardant, multi-effect anti-dripping agent, and heat stabilizer is 3-3.5% of the weight of polystyrene; more preferably, it is 3-3.3%.

[0013] Preferably, the weight ratio of the bromide flame retardant, multi-effect anti-dripping agent, and heat stabilizer is 100:20-30:4-5.

[0014] A method for preparing the aforementioned non-drip flame-retardant expanded polystyrene material includes the following steps: preparing a composite flame retardant and molding; The method for preparing the composite flame retardant is to mix bromide flame retardant, multi-effect anti-dripping agent and heat stabilizer and put them into an internal mixer, and then melt and mix, cool and crush them to obtain the composite flame retardant. The molding method involves melting and blending a composite flame retardant with polystyrene in a twin-screw extruder, adding a foaming agent to foam the mixture, and then extruding it to obtain a non-dripping flame-retardant foamed polystyrene material.

[0015] Preferably, in the preparation of the composite flame retardant, the melt mixing temperature is 80-140℃; more preferably, it is 80-100℃.

[0016] Preferably, the extrusion temperature during the molding process is 80-180℃; more preferably, it is 160-180℃.

[0017] Preferably, in the molding process, the foaming agent is at least one of the following: Freon, ethanol, water, and carbon dioxide.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The non-dripping flame-retardant expanded polystyrene material and its preparation method of the present invention, by selecting a variety of multi-effect anti-dripping agents and using them in combination with bromide flame retardants and heat stabilizers in the flame-retardant treatment of expanded polystyrene, can effectively improve the dripping problem of expanded polystyrene material during combustion without affecting the foaming performance, thermal insulation performance and physical properties of expanded polystyrene material, and at the same time play a certain degree of synergistic flame-retardant effect. Under the condition of low addition amount of composite flame retardant (3-3.4wt%), it can give expanded polystyrene material excellent anti-dripping performance and flame-retardant performance.

[0019] (2) According to the test, the non-drip flame-retardant expanded polystyrene material of the present invention has no defects such as bubbles, bright bands, and black bands on the surface of the board, and has a good foaming effect. Under the condition that the amount of composite flame retardant added is 3.0-3.3wt%, the limiting oxygen index (LOI) can reach 30.2-33.9%. In the vertical burning test, the flame-retardant expanded polystyrene material with a thickness of 3.2mm and 1.6mm did not have dripping phenomenon and both reached UL 94 V-0 level.

[0020] (3) Through testing, the non-drip flame-retardant expanded polystyrene material of the present invention, with a composite flame retardant addition amount of 3.0-3.3 wt%, has an apparent density of 29.2-29.3 kg / m³. 3It has a thermal conductivity of 0.034-0.035 W / m·K and a compressive strength of 312-320 kPa. Detailed Implementation

[0021] To provide a clearer understanding of the technical features, objectives, and effects of the present invention, specific embodiments of the present invention are now described.

[0022] Example 1 A method for preparing a non-drip flame-retardant expanded polystyrene foam material, specifically comprising: 250g of methyl octabromoether, 60g of polytetrafluoroethylene microspheres, 15g of talc, 3g of calcium stearate, 3g of magnesium stearate, and 6g of melamine were mixed and added into a mixer. The melt mixing temperature was controlled at 85℃. After melt mixing, cooling, and crushing, a composite flame retardant was obtained. The composite flame retardant was added to 9.7kg of general-purpose polystyrene resin in a twin-screw extruder for melt blending. At the same time, during the melt blending process, a foaming agent Freon / CO2 was added to foam the resin. The extrusion temperature was controlled at 180℃, and the resin was extruded to obtain a non-dripping flame-retardant foamed polystyrene board containing 3.4wt% composite flame retardant.

[0023] Testing revealed that the surface of the non-drip flame-retardant expanded polystyrene board of this embodiment was free of defects such as bubbles, bright bands, and black bands, exhibiting good foaming effect and an apparent density of 29.4 kg / m³. 3 The thermal conductivity is 0.035 W / m·K, the compressive strength is 305 kPa, and the limiting oxygen index is 29.7%. In the vertical burning test, the 3.2 mm flame-retardant expanded polystyrene foam board had no molten droplets, reaching the UL 94 V-0 level; the 1.6 mm flame-retardant expanded polystyrene foam board still had a few molten droplets, reaching the UL 94 V-2 level.

[0024] Example 2 A method for preparing a non-drip flame-retardant expanded polystyrene foam material, specifically comprising: 250g of brominated SBS, 50g of styrene-acrylonitrile coated polytetrafluoroethylene, 20g of nano-montmorillonite, 3g of calcium stearate, 3g of barium stearate, and 6g of piperazine were mixed and added into a mixer. The melt mixing temperature was controlled at 85℃. After melt mixing, cooling, and crushing, a composite flame retardant was obtained. The composite flame retardant was added to 9.7kg of general-purpose polystyrene resin in a twin-screw extruder for melt blending. At the same time, during the melt blending process, a foaming agent Freon / ethanol / water was added for foaming. The extrusion temperature was controlled at 180℃, and the product was extruded to obtain a non-dripping flame-retardant foamed polystyrene board containing 3.3wt% composite flame retardant.

[0025] The preparation method of styrene-acrylonitrile coated polytetrafluoroethylene is as follows: Sodium dodecylbenzenesulfonate was added to deionized water and stirred until dissolved. Then, acrylonitrile monomer, styrene monomer, and dodecyl mercaptan were added and mixed thoroughly to obtain a monomer emulsion. The weight ratio of sodium dodecylbenzenesulfonate, acrylonitrile monomer, styrene monomer, dodecyl mercaptan, and deionized water was 1.2:85:60:0.8:200.

[0026] The polytetrafluoroethylene emulsion (solid content of 60%) was adjusted to 15% with deionized water to obtain a reaction emulsion. Then, dodecyl mercaptan (0.7% of the weight of the reaction emulsion) and monomer emulsion (10% of the weight of the reaction emulsion) were added. After stirring for 30 min, the temperature was raised to 90℃, and ammonium persulfate was added while maintaining the temperature. Then, under the condition of maintaining the temperature and stirring, 0.7 times the volume of the reaction emulsion monomer emulsion was added dropwise. After the monomer emulsion was added, the reaction was continued to be maintained at the temperature for 2.5 h. Then, after coagulation, washing with water and drying, styrene-acrylonitrile coated polytetrafluoroethylene was obtained.

[0027] Testing revealed that the surface of the non-drip flame-retardant expanded polystyrene board in this embodiment was free of defects such as bubbles, bright bands, and black bands, indicating good foaming performance. The apparent density of this sample was 29.3 kg / m³. 3 The thermal conductivity is 0.034 W / m·K, the compressive strength is 312 kPa, and the limiting oxygen index is 30.2%. In the vertical burning test, the flame-retardant expanded polystyrene foam boards with thicknesses of 3.2 mm and 1.6 mm showed no dripping phenomenon and both reached the UL 94 V-0 rating.

[0028] Example 3 A method for preparing a non-drip flame-retardant expanded polystyrene foam material, specifically comprising: 150g of methyl octabromoether, 90g of brominated SBS, 20g of polytetrafluoroethylene microspheres, 30g of octaphenyl cage-like polysilsesquioxane, 4g of calcium stearate, and 6g of piperazine diphosphate were mixed and added into a mixer. The melt mixing temperature was controlled at 85℃. After melt mixing, cooling, and crushing, a composite flame retardant was obtained. The composite flame retardant was added to 9.7kg of general-purpose polystyrene resin in a twin-screw extruder for melt blending. At the same time, during the melt blending process, a foaming agent Freon / CO2 / water was added for foaming. The extrusion temperature was controlled at 180℃, and the product was extruded to obtain a non-dripping flame-retardant foamed polystyrene board containing 3.0wt% composite flame retardant.

[0029] Among them, the purity of octaphenyl cage-like polysilsesquioxane is ≥99wt%.

[0030] Testing revealed that the surface of the non-drip flame-retardant expanded polystyrene board of this embodiment was free of defects such as bubbles, bright bands, and black bands, exhibiting good foaming effect and an apparent density of 29.2 kg / m³. 3The thermal conductivity is 0.034 W / m·K, the compressive strength is 318 kPa, and the limiting oxygen index is 32.4%. In the vertical burning test, the flame-retardant expanded polystyrene foam boards with thicknesses of 3.2 mm and 1.6 mm showed no dripping phenomenon and both reached the UL 94 V-0 rating.

[0031] Example 4 A method for preparing a non-drip flame-retardant expanded polystyrene foam material, specifically comprising: 120g of methyl octabromoether, 120g of SBS bromide, 25g of octaphenyl cage-like polysilsesquioxane, 25g of octavinyl cage-like polysilsesquioxane, 2g of magnesium stearate, 4g of melamine, and 4g of piperazine diphosphate were mixed and added into a mixer. The melt mixing temperature was controlled at 85℃. After melt mixing, cooling, and crushing, a composite flame retardant was obtained. The composite flame retardant was added to 9.7kg of general-purpose polystyrene resin in a twin-screw extruder for melt blending. At the same time, during the melt blending process, a foaming agent Freon / ethanol / CO2 was added for foaming. The extrusion temperature was controlled at 180℃, and the product was extruded to obtain a non-dripping flame-retardant foamed polystyrene board containing 3.0wt% composite flame retardant.

[0032] Among them, the purity of octaphenyl cage-like polysilsesquioxane is ≥99wt%; the purity of octavinyl cage-like polysilsesquioxane is ≥90wt%.

[0033] Testing revealed that the surface of the non-drip flame-retardant expanded polystyrene board of this embodiment was free of defects such as bubbles, bright bands, and black bands, exhibiting good foaming effect and an apparent density of 29.2 kg / m³. 3 The thermal conductivity is 0.034 W / m·k, the compressive strength is 320 kPa, and the limiting oxygen index is 33.9%. In the vertical burning test, the flame-retardant expanded polystyrene foam boards with thicknesses of 3.2 mm and 1.6 mm showed no dripping phenomenon and both reached the UL 94 V-0 rating.

[0034] Example 5 A method for preparing a non-drip flame-retardant expanded polystyrene foam material, specifically comprising: 90g of methyl octabromoether, 150g of brominated SBS, 20g of styrene-acrylonitrile coated polytetrafluoroethylene, 30g of octavinyl cage-like polysilsesquioxane, 4g of barium stearate, 4g of melamine, and 4g of piperazine were mixed and added into a mixer. The melt mixing temperature was controlled at 85℃. After melt mixing, cooling, and crushing, a composite flame retardant was obtained. The composite flame retardant was added to 9.7kg of general-purpose polystyrene resin in a twin-screw extruder for melt blending. At the same time, during the melt blending process, a foaming agent Freon / CO2 was added to foam the resin. The extrusion temperature was controlled at 180℃, and the resin was extruded to obtain a non-dripping flame-retardant foamed polystyrene board containing 3.0wt% composite flame retardant.

[0035] Testing revealed that the surface of the non-drip flame-retardant expanded polystyrene board of this embodiment was free of defects such as bubbles, bright bands, and black bands, exhibiting good foaming effect and an apparent density of 29.2 kg / m³. 3 The thermal conductivity is 0.034 W / m·K, the compressive strength is 317 kPa, and the limiting oxygen index is 32.2%. In the vertical burning test, the flame-retardant expanded polystyrene foam boards with thicknesses of 3.2 mm and 1.6 mm showed no dripping phenomenon and both reached the UL 94 V-0 rating.

[0036] Comparative Example 1 Corresponding to Example 1, the preparation method of the flame-retardant expanded polystyrene material in this comparative example is as follows: 300g of methyl octabromoether, 100g of talc, and 30g of calcium stearate were mixed and added into a mixer. The melt mixing temperature was controlled at 85℃. After melt mixing, cooling, and crushing, a composite flame retardant was obtained. The composite flame retardant was then added to 9.6kg of general-purpose polystyrene resin in a twin-screw extruder for melt blending. Simultaneously, during the melt blending process, a foaming agent, Freon / ethanol, was added for foaming. The extrusion temperature was controlled at 180℃, and the mixture was extruded to obtain a flame-retardant foamed polystyrene board containing 4.3wt% composite flame retardant.

[0037] Testing revealed that the flame-retardant expanded polystyrene board in Comparative Example 1 had visible bubbles on its surface, indicating a mediocre foaming effect, with an apparent density of 29.6 kg / m³. 3 The thermal conductivity is 0.037 W / m·K, the compressive strength is 298 kPa, and the limiting oxygen index is 28.3%. In the vertical burning test, the 3.2 mm flame-retardant expanded polystyrene foam board showed no dripping and reached the UL 94 V-0 level, but the 1.6 mm flame-retardant expanded polystyrene foam board showed severe dripping and reached the V-2 level.

[0038] Comparative Example 2 Corresponding to Example 2, the preparation method of the flame-retardant expanded polystyrene material in this comparative example is as follows: 300g of brominated SBS, 50g of talc, 50g of nano-montmorillonite, 20g of calcium stearate, and 10g of barium stearate were mixed and added into a mixer. The melt mixing temperature was controlled at 85℃. After melt mixing, cooling, and crushing, a composite flame retardant was obtained. The composite flame retardant was added to 9.6kg of general-purpose polystyrene resin in a twin-screw extruder for melt blending. At the same time, during the melt blending process, a foaming agent, Freon / CO2, was added to foam the resin. The extrusion temperature was controlled at 180℃, and the resin was extruded to obtain a flame-retardant foamed polystyrene board containing 4.3wt% composite flame retardant.

[0039] Testing revealed that the surface of the drip-retardant expanded polystyrene board in Comparative Example 2 showed bubbles and grayish-white bands, indicating unsatisfactory foaming performance. Its apparent density was 29.7 kg / m³. 3 The thermal conductivity is 0.038 W / m·K, the compressive strength is 300 kPa, and the limiting oxygen index is 28.2%. In the vertical burning test, the 3.2 mm flame-retardant expanded polystyrene foam board showed no dripping and reached the UL 94 V-0 level, but the 1.6 mm flame-retardant expanded polystyrene foam board showed severe dripping and was rated V-2.

[0040] Comparative Example 3 Corresponding to Examples 3-5, the preparation method of the flame-retardant expanded polystyrene material in this comparative example is as follows: 150g of methyl octabromoether, 150g of brominated SBS, 70g of talc, 30g of nano-montmorillonite, and 30g of calcium stearate were mixed and added into a mixer. The melt mixing temperature was controlled at 85℃. After melt mixing, cooling, and crushing, a composite flame retardant was obtained. The composite flame retardant was added to 9.6kg of general-purpose polystyrene resin in a twin-screw extruder for melt blending. At the same time, during the melt blending process, a foaming agent Freon / ethanol / CO2 was added for foaming. The extrusion temperature was controlled at 180℃, and the product was extruded to obtain a flame-retardant foamed polystyrene board containing 4.3wt% composite flame retardant.

[0041] Testing revealed that the flame-retardant expanded polystyrene board in Comparative Example 3 had a small number of bubbles on its surface, indicating a mediocre foaming effect, with an apparent density of 29.6 kg / m³. 3 The thermal conductivity is 0.036 W / m·K, the compressive strength is 301 kPa, and the limiting oxygen index is 28.8%. In the vertical burning test, the 3.2 mm flame-retardant expanded polystyrene foam board showed no dripping and reached the UL 94 V-0 level, but the 1.6 mm flame-retardant expanded polystyrene foam board showed more severe dripping and was rated V-2.

[0042] The flame retardant properties of flame-retardant expanded polystyrene boards from Examples 1-5 and Comparative Examples 1-3 are summarized in the table below:

[0043] The physical properties of the flame-retardant expanded polystyrene boards of Examples 1-5 and Comparative Examples 1-3 are summarized in the table below:

[0044] As can be seen, compared with Comparative Examples 1-3, the non-drip flame-retardant expanded polystyrene material and its preparation method of the present invention, by selecting a variety of multi-effect anti-drip agents and combining them with bromide flame retardants and heat stabilizers in the flame-retardant treatment of expanded polystyrene, can effectively improve the dripping problem of expanded polystyrene material during combustion without affecting its foaming performance, thermal insulation performance, and physical properties. It also plays a certain degree of synergistic flame-retardant role, and can impart excellent anti-drip and flame-retardant properties to expanded polystyrene material at a relatively low composite flame retardant addition amount (3-3.4wt%). Specifically, the non-drip flame-retardant expanded polystyrene board has no defects such as bubbles, bright bands, or black bands on its surface, and the foaming effect is good. With a composite flame retardant addition amount of 3.0-3.3wt%, the limiting oxygen index (LOI) can reach 30.2-33.9%. In vertical burning tests, flame-retardant expanded polystyrene materials with thicknesses of 3.2mm and 1.6mm showed no dripping phenomenon and both met UL 94 standards. V-0 rating, with good anti-dripping and flame-retardant properties; meanwhile, the apparent density of the non-dripping flame-retardant expanded polystyrene foam is 29.2-29.3 kg / m³. 3 It has a thermal conductivity of 0.034-0.035 W / m·K, a compressive strength of 312-320 kPa, and good thermal insulation and physical properties.

[0045] Unless otherwise stated, all percentages used in this invention are mass percentages.

[0046] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A non-drip flame-retardant expanded polystyrene foam material, characterized in that, It includes the following raw materials: polystyrene, bromide flame retardant, multi-effect anti-dripping agent, and heat stabilizer; The total weight of the bromide flame retardant, multi-effect anti-dripping agent, and heat stabilizer is 3-3.5% of the weight of polystyrene. The weight ratio of the bromide flame retardant, multi-effect anti-dripping agent, and heat stabilizer is 100:20-30:4-5; The multi-effect anti-dripping agent and the heat stabilizer are one of the following combinations: When the multi-effect anti-dripping agent is a combination of polytetrafluoroethylene microspheres and talc, the heat stabilizer is a combination of calcium stearate, magnesium stearate and melamine. When the multi-effect anti-dripping agent is a combination of styrene-acrylonitrile coated polytetrafluoroethylene and nano-montmorillonite, the heat stabilizer is a combination of calcium stearate, barium stearate and piperazine; When the multi-effect anti-dripping agent is a combination of polytetrafluoroethylene microspheres and octaphenyl cage-like polysilsesquioxane, the heat stabilizer is a combination of calcium stearate and piperazine diphosphate. When the multi-effect anti-dripping agent is a combination of octaphenyl cage polysilsesquioxane and octavinyl cage polysilsesquioxane, the heat stabilizer is a combination of magnesium stearate, melamine and piperazine diphosphate. When the multi-effect anti-dripping agent is a combination of styrene-acrylonitrile-coated polytetrafluoroethylene and octavinyl cage-like polysilsesquioxane, the heat stabilizer is a combination of barium stearate, melamine and piperazine.

2. The non-drip flame-retardant expanded polystyrene material according to claim 1, characterized in that, The bromide flame retardant is at least one of the following: methyl octabromoether, brominated styrene-butadiene-styrene block copolymer.

3. The non-drip flame-retardant expanded polystyrene material according to claim 2, characterized in that, When the bromide flame retardant is methyl octabromoether and brominated styrene-butadiene-styrene block copolymer, the weight ratio of methyl octabromoether and brominated styrene-butadiene-styrene block copolymer is 0.5-1:0.5-1.

4. A method for preparing a non-drip flame-retardant expanded polystyrene material according to any one of claims 1-3, characterized in that, The preparation method includes the following steps: preparing a composite flame retardant and molding; The method for preparing the composite flame retardant is to mix bromide flame retardant, multi-effect anti-dripping agent and heat stabilizer and put them into an internal mixer, and then melt and mix, cool and crush them to obtain the composite flame retardant. The molding method involves melting and blending a composite flame retardant with polystyrene in a twin-screw extruder, adding a foaming agent to foam the mixture, and then extruding it to obtain a non-dripping flame-retardant foamed polystyrene material.

5. The method for preparing the non-drip flame-retardant expanded polystyrene material according to claim 4, characterized in that, In the preparation of the composite flame retardant, the melt mixing temperature is 80-140℃.

6. The method for preparing the non-drip flame-retardant expanded polystyrene material according to claim 4, characterized in that, During the molding process, the extrusion temperature is 80-180℃.

7. The method for preparing the non-drip flame-retardant expanded polystyrene material according to claim 4, characterized in that, In the molding process, the foaming agent is at least one of the following: Freon, ethanol, water, and carbon dioxide.

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