A ablative-resistant ceramicized polypropylene material and a method for preparing the same

Abstract

This application discloses an ablation-resistant ceramicized polypropylene material and its preparation method. The polypropylene material comprises: 40-60 parts of polypropylene ceramic masterbatch, 30-40 parts of polypropylene glass fiber masterbatch, 20-30 parts of polyphenylene sulfide, and 0.5-1.0 parts of antioxidant. The polypropylene ceramic masterbatch comprises: 10 parts of polypropylene, 10-15 parts of ceramic powder, 5-12 parts of glass powder, and 0.5-2 parts of other additives. The polypropylene glass fiber masterbatch comprises: 10 parts of polypropylene, 5-10 parts of glass fiber, 2-5 parts of flame retardant, and 0.5-2 parts of other additives. The melt index of the polypropylene at 230℃ / 2.16Kg is 20-30 g / 10min, and the melt index of the polyphenylene sulfide at 315℃ / 5Kg is 150-300 g / 10min. This application can effectively overcome the problem of easy burn-through in polypropylene-based ceramicized materials before the formation of the ceramic layer.

Description

Technical Field

[0001] This application relates to the field of polypropylene materials, and in particular to an ablation-resistant ceramicized polypropylene material and its preparation method. Background Technology

[0002] Ceramicized polypropylene is a type of functional polymer composite material that can rapidly transform into a self-supporting ceramic barrier under high-temperature flame conditions. Due to its unique ceramic-forming behavior, this material can effectively prevent flame spread, heat transfer, and oxygen permeation during combustion, and is therefore widely used in products with extremely high fire safety requirements, such as battery pack casings, covers, and electronic components.

[0003] In existing technologies, polypropylene is typically used as the base resin. By adding large amounts of glass powder, ceramic fillers, and flame retardants, the glass powder melts into a liquid phase when exposed to open flame, then sintersects with the ceramic fillers and bonds the residual char layer, ultimately constructing a ceramicized protective layer with a certain strength. However, polypropylene itself has inherent defects such as poor heat resistance and a low decomposition temperature. Its thermal decomposition initiation temperature is lower than the temperature at which the glass powder and ceramic fillers begin to soften or participate in the ceramicization reaction. This mismatch in temperature windows leads to the polypropylene matrix decomposing, melting, or even collapsing before the glass powder has fully melted and the ceramic layer has formed a complete structure under actual fire conditions. This results in localized ablation points or complete burn-through on the material surface. Once ablation points form, the flame will directly penetrate the material, and high-temperature smoke will rapidly spread into the battery pack, easily triggering a thermal runaway chain reaction in adjacent battery cells, seriously threatening the overall safety of the battery pack. Therefore, how to significantly improve the ablation resistance of polypropylene-based composites before the formation of the ceramic layer, while ensuring good processability and mechanical properties, and avoid burn-through failure caused by premature decomposition of the matrix, has become a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0004] This application provides an ablation-resistant ceramicized polypropylene material and its preparation method, aiming to solve the problem that polypropylene-based ceramicized materials are prone to burn-through before the ceramic layer is formed.

[0005] In a first aspect, this application provides an ablation-resistant ceramicized polypropylene material, comprising the following raw materials in parts by weight: The composition comprises: 40-60 parts polypropylene ceramic masterbatch, 30-40 parts polypropylene glass fiber masterbatch, 20-30 parts polyphenylene sulfide, and 0.5-1.0 parts antioxidant; the polypropylene ceramic masterbatch includes the following components in parts by weight: 10 parts polypropylene, 10-15 parts ceramic powder, 5-12 parts glass powder, and 0.5-2 parts other additives; the polypropylene glass fiber masterbatch includes the following raw materials in parts by weight: 10 parts polypropylene, 5-10 parts glass fiber, 2-5 parts flame retardant, and 0.5-2 parts other additives; the polypropylene has a melt index of 20-30 g / 10 min at 230℃ / 2.16 kg, and the polyphenylene sulfide has a melt index of 150-300 g / 10 min at 315℃ / 5 kg.

[0006] This application uses polypropylene ceramic masterbatch and polypropylene glass fiber masterbatch as base materials, firstly ensuring that the materials possess good mechanical and processing properties under normal conditions, and secondly providing the necessary foundation for the rapid formation of the ceramic layer during subsequent combustion. Furthermore, this application introduces a small amount of polyphenylene sulfide (PPS), which has excellent heat resistance, and utilizes the phase enrichment behavior of polypropylene and PPS due to viscosity differences during melt processing to achieve the preparation of a high-heat-resistant core-skin structure.

[0007] Specifically, this application first selects polypropylene with a specific melt index range, suitable for the preparation of battery pack shells, covers, and electronic and electrical accessories; then, it selects polyphenylene sulfide with a high melt index, resulting in a significant difference in melt index (viscosity) between the two. In the strong shear field of screw extrusion, the lower viscosity and better flowability of the polyphenylene sulfide melt tends to migrate towards the die wall (surface layer) region with a higher shear rate, while the higher viscosity and poorer flowability of the polypropylene (PP) melt tends to migrate towards the center (core layer) region with a lower shear rate, in order to minimize viscous dissipation. Therefore, polyphenylene sulfide is more likely to accumulate on the surface layer of the material, thus forming a skin layer with PP as the continuous phase and a large amount of PPS as the dispersed phase, and a core layer with PP as the continuous phase and a small amount of PPS as the dispersed phase. This core-skin structure allows the material to maintain high heat resistance on the surface when subjected to flame attack, effectively preventing flame penetration and allowing time for the glass powder to fully melt and the ceramic layer to be fully constructed. This ensures that the material is not burned through before forming a dense ceramic protective body, significantly improving the material's ablation resistance and the overall safety of the battery pack.

[0008] It should be noted that if the melt index of polyphenylene sulfide is too low, it will be difficult for it to migrate and enrich to the surface during melt processing, and the skin-core layered structure cannot be fully formed; if the melt index is too high, macroscopic phase separation will occur between the two phases, which will lead to serious deterioration of the material's mechanical properties.

[0009] In any of the above technical solutions, the polyphenylene sulfide is a modified polyphenylene sulfide grafted with a nano-nucleating agent.

[0010] In any of the above technical solutions, the preparation method of the modified polyphenylene sulfide includes: By grafting an alkenylsilane coupling agent onto the surface of a nanonucleating agent, an alkenylated nanonucleating agent is obtained. Modified polyphenylene sulfide was prepared by melt grafting of alkenylated nanonucleating agents with polyphenylene sulfide under the action of an initiator.

[0011] In any of the above technical solutions, the mass ratio of the nanonucleating agent to the alkenylsilane coupling agent is 100:1 to 3.

[0012] In any of the above technical solutions, the mass ratio of the polyphenylene sulfide, the alkenylated nanonucleating agent and the initiator is 100:0.5~1.5:0.1~1.

[0013] In any of the above technical solutions, the alkenylsilane coupling agent is selected from at least one of vinyltrimethoxysilane, vinyltriethoxysilane, acryloyloxytrimethoxysilane, and acryloyloxytriethoxysilane.

[0014] In any of the above technical solutions, the nanonucleating agent is selected from one or more of nano calcium carbonate, nano silica, nano montmorillonite, and nano talc, and its particle size is 20-100 nm.

[0015] In any of the above technical solutions, the initiator is selected from one or more of benzoyl peroxide, dicumyl peroxide, and azobisisobutyronitrile.

[0016] The interfacial bonding between the polyphenylene sulfide (PP) and polypropylene phases used in this application is poor, which is detrimental to improving the mechanical properties of PP materials, especially impact toughness and flexural strength. To solve this problem, this application uses modified PP grafted with nano-nucleating agents. Nano-nucleating agents are grafted onto the PP molecular chains using alkenyl silane coupling agents. These grafted nano-nucleating agents on the PP surface act as heterogeneous nucleation sites, inducing the polypropylene molecular chains to align orderly on the surface and form polypropylene crystals during the cooling and crystallization process after melt processing. This results in the in-situ formation of a polypropylene crystalline shell layer on the surface of the PP dispersed phase. The PP can then achieve molecular chain entanglement and diffusion with the polypropylene matrix through this shell layer, thus forming a strong interfacial bond. Without the use of additional compatibilizers, the interfacial bonding strength between the PP phase and the polypropylene matrix is ​​significantly improved, enabling the material to maintain excellent ablation resistance while possessing good mechanical properties, achieving a synergistic improvement in both ablation resistance and mechanical properties.

[0017] In any of the above technical solutions, the glass powder includes low melting point glass powder with a melting point of 330-450℃ and high melting point glass powder with a melting point of 500-800℃, and the mass ratio of the low melting point glass powder to the high melting point glass powder is 2-3:1-2.

[0018] In any of the above technical solutions, the surface of the low-melting-point glass powder is grafted with an aminosilane coupling agent, and the surface of the high-melting-point glass powder is grafted with a long-chain alkylsilane coupling agent.

[0019] In any of the above technical solutions, the low melting point glass powder is borosilicate glass powder.

[0020] In any of the above technical solutions, the high melting point glass powder is silicate glass powder and / or aluminosilicate glass powder.

[0021] This application employs a blend of low-melting-point and high-melting-point glass powders. The low-melting-point glass powder softens and melts early in the decomposition of polypropylene, rapidly forming a liquid phase that fills the pores and cracks created by matrix decomposition. Simultaneously, it binds the surrounding ceramic filler and residual carbon layer, quickly forming a preliminary ceramic barrier on the material surface. This effectively prevents direct flame penetration and further oxygen diffusion, allowing time for subsequent high-temperature ceramic structural strengthening. As the temperature rises further, the high-melting-point glass powder begins to function. With its higher softening temperature, it gradually melts within the well-spread low-melting-point component framework and undergoes a eutectic reaction with the ceramic filler, forming a dense, high-strength rigid ceramic framework. This dual-melting-point blend ensures that the ceramic layer remains dense and possesses a certain level of mechanical strength from low to high temperatures.

[0022] More importantly, this application also actively controls the spatial distribution of glass powders with different melting points in the material by differentially modifying their surface chemicals. Specifically, aminosilane coupling agents are grafted onto the surface of low-melting-point glass powder. Amino groups and polypropylene molecular chains have similar nonpolar structures, and the grafted low-melting-point glass powder easily accumulates in the surface region along with polyphenylene sulfide, placing it precisely where early ceramic formation is required. When the flame first attacks the surface layer, the surface-enriched low-melting-point glass powder can respond immediately, rapidly melting to form a liquid phase, maximally filling the voids created by polypropylene decomposition, thereby significantly reducing the ceramic formation temperature and improving the density and continuity of the primary ceramic layer. On the other hand, long-chain alkylsilane coupling agents are grafted onto the surface of high-melting-point glass powder, which has better compatibility with the lower polarity of the core layer, so the high-melting-point glass powder is also mainly distributed in the core region. Once the ceramic layer formed by the low-melting-point glass powder on the surface has initially blocked the flame, the core layer temperature gradually increases. At this point, the high-melting-point glass powder distributed in the core layer begins to melt, further filling and reinforcing the entire ceramic layer. This gradient ceramic formation mechanism results in a ceramic layer that is not only dense and smooth but also possesses excellent resistance to high-temperature creep and impact. Even under continuous burning conditions at 1200℃, the ceramic layer can still maintain an intact rigid framework without softening, dripping, or burning through, thus providing a reliable safety barrier for the battery pack.

[0023] In any of the above technical solutions, the ceramic filler is selected from one or more of kaolin, talc, mica, wollastonite, silica, and brucite.

[0024] In any of the above technical solutions, the flame retardant is selected from one or more of red phosphorus, BDP, RDP, TPP, ADP, ammonium polyphosphate, and melamine polyphosphate.

[0025] In any of the above technical solutions, the other additives include, but are not limited to, one or more of antioxidants, lubricants, and compatibilizers.

[0026] For example, the antioxidant is selected from hindered phenolic antioxidants and / or phosphite antioxidants.

[0027] For example, the lubricant is selected from one or more of calcium stearate, zinc stearate, polyethylene wax, or ultra-high molecular weight silicone masterbatch.

[0028] For example, the compatibilizer is selected from maleic anhydride-grafted polypropylene.

[0029] Secondly, this application provides a method for preparing an ablation-resistant ceramicized polypropylene material, characterized by comprising: Weigh out polypropylene, ceramic powder, glass powder and other additives according to the formula, mix them evenly and then melt-extrude and granulate them through a twin-screw extruder to obtain polypropylene ceramic masterbatch; Weigh out polypropylene, flame retardant, glass fiber and other additives according to the formula, mix them evenly and then melt-extrude and granulate them through a twin-screw extruder to obtain polypropylene glass fiber masterbatch. Weigh out polypropylene ceramic masterbatch, polypropylene glass fiber masterbatch, antioxidant and polyphenylene sulfide according to the formula, mix them evenly and melt extrude and granulate them through a twin-screw extruder to obtain ablation-resistant ceramicized polypropylene material.

[0030] In any of the above technical solutions, the temperature range of the twin-screw extruder is set to 190–230°C during the preparation of the polypropylene ceramic masterbatch. In any of the above technical solutions, the temperature range of the twin-screw extruder is set to 185–225°C during the preparation of the polypropylene glass fiber masterbatch.

[0031] In any of the above technical solutions, the temperature range of the twin-screw extruder in the preparation of the ablation-resistant ceramicized polypropylene material is set as follows: feeding section 190~220℃, melting section 250~280℃, homogenization section 280~295℃, and die head temperature 275~290℃.

[0032] By optimizing the processing temperature window, PPS can be fully melted. Combined with the antioxidant system, the degree of thermal degradation of PP during the melt processing can be effectively controlled, so that the material can obtain excellent ablation resistance while maintaining high mechanical properties.

[0033] In summary, this application has the following beneficial effects: This application first utilizes the viscosity difference between polypropylene and polyphenylene sulfide (PPS) to spontaneously form a core-skin structure with a polypropylene-enriched core layer and a PPS-enriched surface layer during melt processing. This allows the highly heat-resistant surface layer to provide support for the formation of the ceramic layer during flame attack, effectively preventing burn-through. Secondly, by grafting a nano-nucleating agent onto the PPS surface, polypropylene is induced to crystallize at its interface. This significantly improves the poor interfacial bonding caused by compatibility differences without the use of compatibilizers, achieving a balance between mechanical properties and ablation resistance. Furthermore, by differentially modifying the surface of glass powders with different melting points, a zoned distribution of a low-melting-point glass powder-enriched surface layer and a high-melting-point glass powder-enriched core layer is achieved, forming a gradient ceramic formation mechanism of low-temperature surface ceramic formation and high-temperature core layer reinforcement. These methods enable the material to rapidly form a dense, high-strength ceramic protective layer during combustion, while maintaining good processability and mechanical strength. Detailed Implementation

[0034] Preparation Example Preparation Example 1-1, modified polyphenylene sulfide, the preparation method is as follows: 100 g of nano-calcium carbonate with an average particle size of 50 nm was weighed and placed in a three-necked flask. 400 mL of anhydrous ethanol was added, and the mixture was ultrasonically dispersed for 30 min to ensure complete dispersion of the nanoparticles. 2.0 g of vinyltrimethoxysilane was weighed and dissolved in 20 mL of an ethanol-water solution (5 wt% water). Glacial acetic acid was added to adjust the pH to 3.5–4.0, and the solution was hydrolyzed at room temperature for 10 min. The hydrolyzed silane coupling agent solution was added dropwise to the three-necked flask while stirring. After the addition was complete, the temperature was raised to 60 °C, and the reaction was continued with stirring for 4 h. After the reaction was complete, the product was filtered and washed three times each with anhydrous ethanol and deionized water. The solid product was collected and placed in a vacuum drying oven, dried at 80 °C for 12 h, and then ground through a 200-mesh sieve to obtain the alkenylated nanonucleating agent.

[0035] Weigh 10.0 g of the above-mentioned alkenylated nanonucleating agent and premix it with 1000 g of polyphenylene sulfide (Chongqing Jushi GL03, melt index approximately 200 g / 10 min) in a high-speed mixer at room temperature and 500 rpm for 2 min. Then add 4.0 g of benzoyl peroxide and continue mixing for 2 min to obtain a premixed material. The premixed material is melt-extruded and granulated using a twin-screw extruder. The extruder temperatures are set as follows: feeding section 260℃, melting section 285℃, homogenization section 295℃, die head temperature 290℃, screw speed 250 rpm, and vacuum exhaust port opening with a vacuum degree of -0.06 MPa. After cooling in a water bath, the extruded strip is granulated. The resulting granules are placed in a vacuum drying oven and dried at 130℃ for 6 h to obtain modified polyphenylene sulfide.

[0036] Preparation Examples 1-2: Modified polyphenylene sulfide, prepared by the following method: 100g of nano-silica with an average particle size of 30nm was weighed and placed in a three-necked flask. 500mL of anhydrous ethanol was added, and the mixture was ultrasonically dispersed for 40min to ensure thorough dispersion of the nanoparticles. 1.0g of vinyltriethoxysilane was weighed and dissolved in 20mL of an ethanol-water solution (5wt% water). Glacial acetic acid was added to adjust the pH to 3.5–4.0, and the solution was hydrolyzed at room temperature for 15min. The hydrolyzed silane coupling agent solution was added dropwise to the three-necked flask while stirring. After the addition was complete, the temperature was raised to 65℃, and the reaction was continued with stirring for 5h. After the reaction was completed, the product was filtered and washed three times each with anhydrous ethanol and deionized water. The solid product was collected and placed in a vacuum drying oven, dried at 80℃ for 12h, and then ground through a 200-mesh sieve to obtain the alkenylated nano-nucleating agent.

[0037] Weigh 6.0 g of the above-mentioned alkenylated nanonucleating agent and premix it with 1000 g of polyphenylene sulfide (Chongqing Jushi GL02, melt index approximately 165 g / 10 min) in a high-speed mixer at room temperature and 500 rpm for 2 min. Then add 3.0 g of dicumyl peroxide and continue mixing for 2 min to obtain a premixed material. The premixed material is melt-extruded and granulated using a twin-screw extruder. The extruder temperatures are set as follows: feeding section 255℃, melting section 280℃, homogenization section 290℃, die head temperature 285℃, screw speed 220 rpm, and vacuum exhaust port opening with a vacuum degree of -0.06 MPa. After cooling in a water bath, the extruded strip is granulated. The resulting granules are placed in a vacuum drying oven and dried at 130℃ for 6 h to obtain modified polyphenylene sulfide.

[0038] Preparation Examples 1-3, modified polyphenylene sulfide, are prepared by the following methods: 100g of nano-calcium carbonate with an average particle size of 50nm was weighed and placed in a three-necked flask. 400mL of anhydrous ethanol was added, and the mixture was ultrasonically dispersed for 30min to ensure thorough dispersion of the nanoparticles. 3.0g of vinyltrimethoxysilane was weighed and dissolved in 20mL of an ethanol-water solution (5wt% water). 0.25g of glacial acetic acid was added to adjust the pH to 3.5–4.0, and the solution was hydrolyzed at room temperature for 10min. The hydrolyzed silane coupling agent solution was added dropwise to the three-necked flask while stirring. After the addition was complete, the temperature was raised to 60℃, and the reaction was continued with stirring for 4h. After the reaction was completed, the product was filtered and washed three times each with anhydrous ethanol and deionized water. The solid product was collected and placed in a vacuum drying oven, dried at 80℃ for 12h, and ground through a 200-mesh sieve to obtain an alkenylated nanonucleating agent (white powder, grafting rate approximately 2.2%).

[0039] Weigh 15g of the above-mentioned alkenylated nanonucleating agent and 1000g of polyphenylene sulfide (Chongqing Jushi GL05, melt index approximately 280g / 10min) with a melt index of approximately 280g / 10min. Premix the mixture in a high-speed mixer at 500rpm for 2min at room temperature. Then add 6.0g of benzoyl peroxide and continue mixing for 2min to obtain a premixed material. Melt-extrude the premixed material using a twin-screw extruder. The extruder temperatures are set as follows: feeding section 265℃, melting section 290℃, homogenization section 300℃, die head temperature 295℃, screw speed 280rpm, and vacuum exhaust port open at -0.06MPa. After cooling in a water bath, the extruded strip is granulated. The resulting granules are placed in a vacuum drying oven and dried at 130℃ for 6h to obtain modified polyphenylene sulfide.

[0040] Preparation Examples 1-4, modified polyphenylene sulfide, differed from Preparation Example 1-1 in that an equal amount of polyphenylene sulfide (Chongqing Jushi GL01, melt index about 135 g / 10 min) was used to replace polyphenylene sulfide (Chongqing Jushi GL03, melt index about 200 g / 10 min).

[0041] Preparation Examples 1-5, modified polyphenylene sulfide, differed from Preparation Example 1-1 in that an equal amount of polyphenylene sulfide (Chongqing Jushi GL06, melt index about 325 g / 10 min) was used to replace polyphenylene sulfide (Chongqing Jushi GL03, melt index about 200 g / 10 min).

[0042] Preparation Example 2-1, modified low-melting-point glass powder, was carried out according to the following procedure: Weigh 500g of low-melting-point borosilicate glass powder (Guizhou Baibo BYBP400, composition B2O3-ZnO, softening point 335±5℃, D90=7.6μm), place it in a glass reactor, add 1000mL of anhydrous ethanol, and ultrasonically disperse for 30min to ensure the glass powder is fully dispersed in the ethanol to form a uniform suspension. Weigh 10.0g of γ-aminopropyltrimethoxysilane, dissolve it in 100mL of ethanol-water solution (water content 5wt%), and hydrolyze it at room temperature for 15min. Add the hydrolyzed silane coupling agent solution dropwise to the reactor while maintaining mechanical stirring during the addition. After the addition is complete, raise the temperature to 65℃ and maintain the reaction temperature for 4h. After the reaction is complete, filter the suspension under vacuum. Wash the filter cake three times each with anhydrous ethanol and deionized water to remove unreacted silane coupling agent and byproducts. The solid product was collected and placed in a vacuum drying oven and dried at 80°C for 12 hours. After drying, it was passed through a 300-mesh sieve to obtain modified low-melting-point glass powder.

[0043] Preparation Example 2-2, modified low-melting-point glass powder, was carried out according to the following procedure: Weigh 500g of low-melting-point borosilicate glass powder (Guizhou Baibo BYBP400, composition B2O3-ZnO, softening point 335±5℃, D90=7.6μm), place it in a glass reactor, add 1000mL of anhydrous ethanol, and ultrasonically disperse for 30min to ensure the glass powder is fully dispersed in the ethanol to form a uniform suspension. Weigh 5g of γ-aminopropyltrimethoxysilane, dissolve it in 50mL of anhydrous ethanol, and hydrolyze it at room temperature for 15min. Add the hydrolyzed silane coupling agent solution dropwise to the reactor while maintaining mechanical stirring during the addition. After the addition is complete, raise the temperature to 65℃ and maintain the reaction temperature for 4h. After the reaction is complete, filter the suspension under vacuum. Wash the filter cake three times each with anhydrous ethanol and deionized water to remove unreacted silane coupling agent and byproducts. The solid product was collected and placed in a vacuum drying oven and dried at 80°C for 12 hours. After drying, it was passed through a 300-mesh sieve to obtain modified low-melting-point glass powder.

[0044] Preparation Example 2-3, modified low-melting-point glass powder, was carried out according to the following operation: Weigh 500g of low-melting-point borosilicate glass powder (Guizhou Baibo BYB0725, composition Bi2O3-B2O3-ZnO, softening point 390±5℃, D90=5.1μm), place it in a glass reactor, add 1000mL of anhydrous ethanol, and ultrasonically disperse for 30min to ensure the glass powder is fully dispersed in the ethanol to form a uniform suspension. Weigh 15.0g of γ-aminopropyltrimethoxysilane, dissolve it in 150mL of ethanol-water solution (water content 5wt%), and hydrolyze it at room temperature for 15min. Add the hydrolyzed silane coupling agent solution dropwise to the reactor while maintaining mechanical stirring during the addition. After the addition is complete, raise the temperature to 65℃ and maintain the reaction temperature for 4h. After the reaction is complete, filter the suspension under vacuum. Wash the filter cake three times each with anhydrous ethanol and deionized water to remove unreacted silane coupling agent and byproducts. The solid product was collected and placed in a vacuum drying oven and dried at 80°C for 12 hours. After drying, it was passed through a 300-mesh sieve to obtain modified low-melting-point glass powder.

[0045] Preparation Example 2-4, modified low-melting-point glass powder, differs from Preparation Example 2-1 in that an equal amount of dodecyltrimethoxysilane is used to replace γ-aminopropyltrimethoxysilane.

[0046] Preparation Example 3-1: Modified high-melting-point glass powder was prepared according to the following operation: Weigh 500g of high-melting-point aluminosilicate glass powder (Kunming Norman Electronics GF-AL-2521, softening point 650℃, average particle size 1-2μm), place it in a 2L glass reactor, add 1000mL of anhydrous ethanol, and ultrasonically disperse for 30min to ensure the glass powder is fully dispersed in the alcohol-water mixture to form a uniform suspension. Weigh 12.5g of dodecyltrimethoxysilane, dissolve it in 100mL of ethanol-water solution (5wt% water), add glacial acetic acid to adjust the pH to 3.5-4.0, and hydrolyze at room temperature for 30min. Add the hydrolyzed silane coupling agent solution dropwise to the reactor while maintaining mechanical stirring during the addition. After the addition is complete, raise the temperature to 70℃ and maintain the reaction temperature for 5h. After the reaction is complete, filter the suspension under vacuum. Wash the filter cake three times each with anhydrous ethanol and deionized water to remove unreacted silane coupling agent and byproducts. The solid product was collected and placed in a vacuum drying oven and dried at 100°C for 8 hours. After drying, it was passed through a 300-mesh sieve to obtain modified high-melting-point glass powder.

[0047] Preparation Example 3-2, modified high melting point glass powder, differs from Preparation Example 3-1 only in that the amount of dodecyltrimethoxysilane used is 5g, and it is dissolved in 50mL of ethanol aqueous solution (water content 5wt%).

[0048] Preparation Example 3-3, modified high melting point glass powder, differs from Preparation Example 3-1 only in that the amount of dodecyltrimethoxysilane used is 15g, and it is dissolved in 150mL of ethanol aqueous solution (water content 5wt%).

[0049] Preparation Example 3-4, modified high melting point glass powder, differs from Preparation Example 3-1 in that an equal amount of γ-aminopropyltrimethoxysilane is used to replace dodecyltrimethoxysilane.

[0050] Example Information on some raw materials used in the following examples: Flame retardant is melamine polyphosphate (purchased from Bost Chemical); Lubricant is silicone masterbatch (purchased from Meichuang Donglai); Resin carrier is LLDPE; Glass fiber diameter is 13μm, linear density is 2400tex; Antioxidant is a compound of antioxidant 1010 and antioxidant 168 in a mass ratio of 1:1.

[0051] Example 1: An ablation-resistant ceramicized polypropylene material was prepared according to the following steps: Weigh out 1000g of polypropylene (Basel HP552R, melt index 25g / 10min), 1200g of kaolin, 600g of modified low-melting-point glass powder (prepared in Preparation Example 2-1), 300g of modified high-melting-point glass powder (prepared in Preparation Example 3-1), 30g of antioxidant, and 70g of lubricant. Mix them in a high-speed mixer at 500rpm for 5min at room temperature. Melt-extrude the uniformly mixed material using a twin-screw extruder. The extruder temperatures are set as follows: feeding section 190℃, melting section 210℃, homogenization section 220℃, die head temperature 215℃, screw speed 450rpm, and vacuum exhaust port opening at -0.06MPa. After cooling in a water bath, the extruded strip is granulated. The resulting granules are then dried in a vacuum drying oven at 80℃ for 4h to obtain polypropylene ceramic masterbatch.

[0052] Weigh 1000g of polypropylene (Basel HP552R, melt index 25g / 10min), 350g of melamine polyphosphate, 30g of antioxidant, and 50g of lubricant. Mix them in a high-speed mixer at 500rpm for 5min at room temperature. The uniformly mixed material is then melt-extruded through a twin-screw extruder. The extruder temperatures are set as follows: feeding section 185℃, melting section 205℃, homogenization section 215℃, die head temperature 210℃, and screw speed 280rpm. The melt-extruded material enters an impregnation tank at 260℃. Glass fibers are introduced into the impregnation tank via guide rollers according to the weight ratio, with a fiber dosage of 780g. After impregnation, the fibers are pulled out by traction rollers, cooled in a cooling water tank, pelletized by a pelletizer, and then dried in a vacuum drying oven at 80℃ for 4h to obtain polypropylene glass fiber masterbatch.

[0053] Weigh out 500g of the prepared polypropylene ceramic masterbatch, 350g of polypropylene glass fiber masterbatch, 230g of modified polyphenylene sulfide (prepared in Example 1-1), 8.5g of antioxidant, and 25g of lubricant. Mix them in a high-speed mixer at 500rpm for 5 minutes at room temperature. Melt-extrude the uniformly mixed material using a twin-screw extruder. The extruder temperatures are set as follows: feeding section 210℃, melting section 270℃, homogenizing section 290℃, die head temperature 285℃, screw speed 350rpm, and vacuum exhaust port opening at -0.06MPa. After cooling in a water bath, the extruded strip is granulated. The resulting granules are then dried in a vacuum drying oven at 80℃ for 4 hours to obtain ablation-resistant ceramicized polypropylene material.

[0054] Example 2: An ablation-resistant ceramicized polypropylene material was prepared according to the following steps: Weigh 1000g of polypropylene (Pro-fax SL645, melt index 20g / 10min), 1000g of kaolin, 360g of modified low-melting-point glass powder (prepared in Preparation Example 2-2), 180g of modified high-melting-point glass powder (prepared in Preparation Example 3-2), 30g of antioxidant, and 30g of lubricant. Mix them in a high-speed mixer at 500rpm for 5min at room temperature. The uniformly mixed material is then melt-extruded and granulated using a twin-screw extruder. The extruder temperatures are set as follows: feeding section 190℃, melting section 210℃, homogenization section 220℃, die head temperature 215℃, screw speed 450rpm, and vacuum exhaust port opening at -0.06MPa. After cooling in a water bath, the extruded strip is granulated. The resulting granules are then dried in a vacuum drying oven at 80℃ for 4h to obtain polypropylene ceramic masterbatch.

[0055] Weigh 1000g of polypropylene (Pro-fax SL645, melt index 20g / 10min), 200g of melamine polyphosphate, 30g of antioxidant, and 35g of lubricant. Mix them in a high-speed mixer at 500rpm for 5min at room temperature. The uniformly mixed material is then melt-extruded through a twin-screw extruder. The extruder temperatures are set as follows: feeding section 185℃, melting section 205℃, homogenization section 215℃, die head temperature 210℃, and screw speed 280rpm. The melt-extruded material enters an impregnation tank at 260℃. Glass fibers are introduced into the impregnation tank via guide rollers according to the weight ratio, with a fiber dosage of 500g. After impregnation, the fibers are pulled out by traction rollers, cooled in a cooling water tank, pelletized by a pelletizer, and then dried in a vacuum drying oven at 80℃ for 4h to obtain polypropylene glass fiber masterbatch.

[0056] Weigh out 400g of the prepared polypropylene ceramic masterbatch, 300g of polypropylene glass fiber masterbatch, 200g of modified polyphenylene sulfide (prepared in Examples 1-2), 5g of antioxidant, and 20g of lubricant. Mix them in a high-speed mixer at 500 rpm for 5 minutes at room temperature. Melt-extrude the uniformly mixed material using a twin-screw extruder. The extruder temperatures are set as follows: feeding section 210℃, melting section 270℃, homogenizing section 290℃, die head temperature 285℃, screw speed 350 rpm, and vacuum exhaust port opening at -0.06 MPa. After cooling in a water bath, the extruded strip is granulated. The resulting granules are then dried in a vacuum drying oven at 80℃ for 4 hours to obtain ablation-resistant ceramicized polypropylene material.

[0057] Example 3: An ablation-resistant ceramicized polypropylene material was prepared according to the following steps: Weigh out 1000g of polypropylene (Basel EP300R, melt index 30g / 10min), 1500g of kaolin, 720g of modified low-melting-point glass powder (prepared in Preparation Example 2-3), 480g of modified high-melting-point glass powder (prepared in Preparation Example 3-3), 50g of antioxidant, and 100g of lubricant. Mix them in a high-speed mixer at 500rpm for 5min at room temperature. The uniformly mixed material is then melt-extruded and granulated using a twin-screw extruder. The extruder temperatures are set as follows: feeding section 190℃, melting section 210℃, homogenization section 220℃, die head temperature 215℃, screw speed 450rpm, and vacuum exhaust port opening at -0.06MPa. After cooling in a water bath, the extruded strip is granulated. The resulting granules are then dried in a vacuum drying oven at 80℃ for 4h to obtain polypropylene ceramic masterbatch.

[0058] Weigh 1000g of polypropylene (Basel EP300R, melt index 30g / 10min), 500g of melamine polyphosphate, 50g of antioxidant, and 100g of lubricant. Mix them in a high-speed mixer at 500rpm for 5min at room temperature. The uniformly mixed material is then melt-extruded through a twin-screw extruder. The extruder temperatures are set as follows: feeding section 185℃, melting section 205℃, homogenization section 215℃, die head temperature 210℃, and screw speed 280rpm. The melt-extruded material enters an impregnation tank at 260℃. Glass fibers are introduced into the impregnation tank via guide rollers according to the weight ratio, with a fiber dosage of 1000g. After impregnation, the fibers are pulled out by traction rollers, cooled in a cooling water tank, pelletized by a pelletizer, and then dried in a vacuum drying oven at 80℃ for 4h to obtain polypropylene glass fiber masterbatch.

[0059] Weigh out 600g of the prepared polypropylene ceramic masterbatch, 400g of polypropylene glass fiber masterbatch, 300g of modified polyphenylene sulfide (prepared in Examples 1-3), 9g of antioxidant, and 30g of lubricant. Mix them in a high-speed mixer at 500 rpm for 5 minutes at room temperature. Melt-extrude the uniformly mixed material using a twin-screw extruder. The extruder temperatures are set as follows: feeding section 215℃, melting section 275℃, homogenizing section 295℃, die head temperature 290℃, screw speed 250 rpm, and vacuum exhaust port opening at -0.06 MPa. After cooling in a water bath, the extruded strip is granulated. The resulting granules are then dried in a vacuum drying oven at 80℃ for 4 hours to obtain ablation-resistant ceramicized polypropylene material.

[0060] Example 4, an ablation-resistant ceramicized polypropylene material, differs from Example 1 in that an equal amount of modified low-melting-point glass powder from Preparation Examples 2-4 is used to replace the modified low-melting-point glass powder from Preparation Example 2-1.

[0061] Example 5, an ablation-resistant ceramicized polypropylene material, differs from Example 1 in that an equal amount of modified high-melting-point glass powder from Preparation Examples 3-4 is used to replace the modified high-melting-point glass powder from Preparation Example 3-1.

[0062] Example 6, an ablation-resistant ceramicized polypropylene material, differs from Example 1 in that an equal amount of unmodified polyphenylene sulfide (Chongqing Jushi GL03, melt index approximately 200 g / 10 min) is used to replace the modified polyphenylene sulfide prepared in Preparation Example 1-1.

[0063] Comparative Example Comparative Example 1 is an ablation-resistant ceramicized polypropylene material, which differs from Example 1 in that an equal amount of modified polyphenylene sulfide prepared in Preparation Examples 1-4 is used instead of the modified polyphenylene sulfide prepared in Preparation Example 1-1.

[0064] Comparative Example 2, an ablation-resistant ceramicized polypropylene material, differs from Example 1 in that an equal amount of modified polyphenylene sulfide prepared in Preparation Examples 1-5 is used instead of the modified polyphenylene sulfide prepared in Preparation Example 1-1.

[0065] Comparative Example 3 is an ablation-resistant ceramicized polypropylene material, which differs from Example 1 in that an equal amount of polypropylene (Pinnacle PP 1635, melt index 35 g / 10 min) is used to replace polypropylene (Basel HP552R, melt index 25 g / 10 min).

[0066] Performance testing Experiment 1: Ablation Resistance Test Sample preparation: The polypropylene materials obtained in the examples and comparative examples were injection molded into rectangular plate-shaped samples with dimensions of 150mm × 100mm × 2mm at an injection temperature of 270–280℃ and a mold temperature of approximately 140℃. Three samples were prepared for each material group, and each sample was marked and then tested.

[0067] Test method: (1) Before the test, the sample was placed under standard environmental conditions (23±2℃, 50±5% relative humidity) for 48h to adjust its state.

[0068] (2) Fix the high-speed butane flame gun vertically on the sample holder, adjust the position of the flame gun so that the nozzle is at an appropriate distance from the sample surface, and ensure that the outer flame temperature is stable at 1200℃. Use a thermocouple thermometer to calibrate the flame temperature, with the measurement point located at the position where the flame tip is aligned with the center of the sample, and control the temperature fluctuation within ±50℃.

[0069] (3) Fix the sample vertically on the support, ensuring that the sample surface is perpendicular to the flame gun axis and the center of the flame gun nozzle is directly opposite the center of the sample. Attach a φ30mm patch thermocouple sensor to the center of the unexposed side of the sample, ensuring that the sensor is in close contact with the unexposed side of the sample. Connect the other end to a temperature recorder to record the temperature change of the unexposed side in real time.

[0070] (4) Turn on the butane gas source, adjust the pressure to 0.5 MPa, and ignite the flame. After the flame temperature stabilizes at 1200℃, aim the flame at the center point of the sample front and start igniting.

[0071] (5) Continue the flame exposure for 15 minutes, and record the temperature of the unexposed surface in real time. If the temperature of the unexposed surface exceeds 1000℃ during the flame exposure, it indicates that the sample has burned through. Stop the test immediately and record the time and temperature at this time.

[0072] (6) After the flame is applied, turn off the gas source and observe and record the burn-through condition of the sample after the sample has cooled naturally (whether it burns through, whether it collapses, etc.).

[0073] The average and maximum temperatures of the unexposed surface of each sample were recorded at 2 min and 15 min after flame exposure. The morphology of the samples after 15 min of flame exposure was also observed and recorded, including whether there was burn-through, collapse, and the density of the char layer. Three samples were tested in each group, and the arithmetic mean was taken.

[0074] Experiment 2: Flame retardant performance test Test method: The flame retardancy rating of the material was determined according to the Vertical Burning Test in UL 94, "Tests for the Flammability of Plastic Materials for Equipment and Appliance Components". The sample size was 125mm × 13mm × 1.6mm. The UL-94 flame retardancy rating (V-0, V-1, V-2, or HB) of the material was recorded, with 5 samples tested per group.

[0075] Experiment 3: Bending Strength Test Sample preparation: The polypropylene materials obtained in the examples and comparative examples were injection molded at an injection temperature of 270–280°C and a mold temperature of approximately 140°C. Rectangular strip samples with dimensions of 80 mm × 10 mm × 4 mm were prepared by injection molding according to GB / T 9341-2008. Five samples were prepared for each material group.

[0076] Test Method: Following the specifications in GB / T 9341-2008 "Determination of Bending Properties of Plastics", a universal testing machine was used to test the bending properties. A three-point loading test method was employed (free support at both ends, central loading). The testing machine should be equipped with a suitable three-point bending fixture. The radius of curvature of the indenter and supports is 5 mm, and the span is set to 64 mm (span-to-thickness ratio of 16:1, specimen thickness 4 mm). The test speed was set to 2 mm / min. The specimen was removed from the constant temperature and humidity environment and placed horizontally on the two supports, with the specimen length direction perpendicular to the supports. The indenter was positioned at the center of the specimen span, ensuring that the longitudinal axis of the specimen was perpendicular to the centerline of the indenter to avoid eccentric loading. The testing machine was started, and the indenter applied a bending load vertically downwards at a constant speed of 2 mm / min, while simultaneously recording the load-deflection curve. The test was stopped when the specimen broke or the maximum deflection reached 5% of the span. For specimens that broke before reaching the specified deflection, the maximum bending load at breakage was recorded; for specimens that did not break, the bending load corresponding to the specified deflection was recorded. The bending strength was calculated, and five parallel specimens were tested in each group. The results were taken as the arithmetic mean.

[0077] Test 4: Impact Resistance (Toughness) Test Sample Preparation: The polypropylene materials obtained in the examples and comparative examples were injection molded at an injection temperature of 270–280°C and a mold temperature of approximately 140°C. Rectangular strip specimens with dimensions of 80 mm × 10 mm × 4 mm were prepared according to the specifications for Type 1 specimens in GB / T 1843-2008. A notch (45° ± 1°, bottom radius R0.25 ± 0.05 mm) was machined in the middle of the specimen, leaving a thickness of 2.8 ± 0.2 mm below the notch. Five notched specimens were prepared for each material group.

[0078] Test Method: Following the specifications in GB / T 1843-2008 "Determination of Impact Strength of Plastic Cantilever Beams", a cantilever beam impact testing machine was used. The impact velocity was 3.5 m / s, and the pendulum pre-lift angle was 150°. The specimen was vertically clamped in the fixture, with the notch facing the pendulum impact blade (pendulum blade radius 0.8 mm), and the upper surface of the specimen flush with the upper surface of the fixture. The width of the specimen and the remaining thickness below the notch were recorded, accurate to 0.02 mm. The pendulum (5.5 J) was released to impact the specimen, and the impact energy absorbed when the specimen fractured was recorded. Complete fracture of the specimen was considered a valid test. If incomplete fracture or delamination occurred, the specimen should be discarded and the test repeated. The cantilever beam impact strength was calculated. Five parallel specimens were tested in each group, and the arithmetic mean of the results was taken.

[0079] Table 1 Performance test results Analysis of experimental results: The difference between Example 4 and Example 1 is that, during the surface treatment of the modified low-melting-point glass powder, dodecyltrimethoxysilane was used instead of γ-aminopropyltrimethoxysilane. The experimental results show that the ablation resistance of Example 4 is significantly deteriorated, specifically manifested in an increase in the average and maximum temperatures on the unexposed surface at 2 min and 15 min. This may be because the grafting of long-chain alkyl groups onto the surface of the low-melting-point glass powder reduces its compatibility with the surface polyphenylene sulfide, preventing effective enrichment on the surface. When the flame attacks the surface, the insufficient quantity of low-melting-point glass powder prevents it from melting immediately to form a dense liquid phase that fills the decomposition pores, resulting in reduced early ceramic formation efficiency and increased unexposed surface temperature.

[0080] The difference between Example 5 and Example 1 is that γ-aminopropyltrimethoxysilane was used instead of dodecyltrimethoxysilane in the surface treatment of the modified high-melting-point glass powder. The experimental results show that the ablation resistance of Example 4 is significantly deteriorated, specifically in the increase of the average and maximum temperatures on the unexposed surface after 15 minutes. This may be because after grafting amino groups onto the surface of the high-melting-point glass powder, its compatibility with the core layer decreases, preventing effective enrichment in the core layer. The high-melting-point glass powder is more distributed on the surface or at the two-phase interface. When the low-melting-point glass powder on the surface initially forms a ceramic layer, as the core layer temperature rises, the amount of high-melting-point glass powder distributed in the core layer is insufficient to effectively replace the low-melting-point components for secondary ceramic formation and structural reinforcement, resulting in insufficient density of the ceramic layer at high temperatures.

[0081] The difference between Example 6 and Example 1 is that unmodified polyphenylene sulfide (PPS) was used. The test results show that the flexural strength and impact strength of Example 6 decreased significantly, and the ablation resistance also decreased markedly, although it did not burn through. This may be because the interfacial bonding between the unmodified PPS and PP is poor, and the lack of a PP crystalline shell induced by a nano-nucleating agent at the interface prevents the mutual entanglement and diffusion of molecular chains. This results in stress not being effectively transferred from the PP matrix to the PPS dispersed phase, leading to severe deterioration of the material's mechanical properties. Furthermore, the reduced dispersibility and bonding strength of the PPS dispersed phase in PP further decreases its ablation resistance compared to Example 1.

[0082] The difference between Comparative Example 1 and Example 1 is that a modified polyphenylene sulfide (PPS) was prepared using a low melt flow index PPS. The experimental results show that the ablation resistance of Comparative Example 1 is severely deteriorated, exhibiting burn-through at approximately 11 minutes in a 15-minute torch combustion test. This may be because when the PPS melt flow index is too low (135 g / 10 min), the viscosity difference between it and PP (25 g / 10 min) is insufficient. Under the shear force field of the screw, the driving force for PPS migration and enrichment to the surface is weak, and the core-skin structure cannot be fully formed. Insufficient PPS content in the surface layer results in insufficient surface heat resistance when the material is subjected to flame attack, failing to effectively prevent flame penetration and significantly reducing ablation resistance.

[0083] The difference between Comparative Example 2 and Example 1 is that a modified polyphenylene sulfide (PPS) was prepared using a high melt flow index PPS. The experimental results show that Comparative Example 2 exhibited the most severe degradation in mechanical properties, failing to meet product performance requirements. This may be because, while a high PPS melt flow index results in strong migration and enrichment towards the surface, the PPS does not form a microphase enrichment within the surface PP layer; instead, macroscopic separation occurs, leading to severe degradation of mechanical properties. Furthermore, the lack of a dispersed phase on the surface makes the PPS prone to localized burn-through, significantly degrading the overall flame retardant performance.

[0084] The difference between Comparative Example 3 and Example 1 is that high melt flow index polypropylene was used. The experimental results show that the mechanical properties of Comparative Example 3 decreased, and its ablation resistance deteriorated significantly, resulting in burn-through. This may be because when the melt flow index of PP is too high, the molecular weight of PP is low, leading to a decrease in its thermal stability and mechanical properties. Simultaneously, the ability of PP with an excessively high melt flow index to migrate and accumulate to the surface decreases, making it difficult to fully form a core-skin structure.

[0085] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A ablative ceramic polypropylene material, characterized in that, The raw materials include the following parts by weight: The composition comprises: 40-60 parts polypropylene ceramic masterbatch, 30-40 parts polypropylene glass fiber masterbatch, 20-30 parts polyphenylene sulfide, and 0.5-1.0 parts antioxidant; the polypropylene ceramic masterbatch includes the following components in parts by weight: 10 parts polypropylene, 10-15 parts ceramic powder, 5-12 parts glass powder, and 0.5-2 parts other additives; the polypropylene glass fiber masterbatch includes the following raw materials in parts by weight: 10 parts polypropylene, 5-10 parts glass fiber, 2-5 parts flame retardant, and 0.5-2 parts other additives; the polypropylene has a melt index of 20-30 g / 10 min at 230℃ / 2.16 kg, and the polyphenylene sulfide has a melt index of 150-300 g / 10 min at 315℃ / 5 kg.

2. The ablative ceramicized polypropylene material according to claim 1, characterized in that, The polyphenylene sulfide is a modified polyphenylene sulfide grafted with a nano-nucleating agent.

3. The ablative ceramicized polypropylene material of claim 1, wherein, The preparation method of the modified polyphenylene sulfide includes: By grafting an alkenylsilane coupling agent onto the surface of a nanonucleating agent, an alkenylated nanonucleating agent is obtained. Modified polyphenylene sulfide was prepared by melt grafting of alkenylated nanonucleating agents with polyphenylene sulfide under the action of an initiator.

4. The ablation-resistant ceramicized polypropylene material according to claim 1, characterized in that, The mass ratio of the nanonucleating agent to the alkenylsilane coupling agent is 100:1 to 3.

5. The ablation-resistant ceramicized polypropylene material according to claim 1, characterized in that, The mass ratio of the polyphenylene sulfide, the alkenylated nanonucleating agent, and the initiator is 100:0.5-1.5:0.1-1.

6. The ablation-resistant ceramicized polypropylene material according to claim 1, characterized in that, The alkenylsilane coupling agent is selected from at least one of vinyltrimethoxysilane, vinyltriethoxysilane, acryloyloxytrimethoxysilane, and acryloyloxytriethoxysilane.

7. The ablation-resistant ceramicized polypropylene material according to claim 1, characterized in that, The glass powder includes low-melting-point glass powder with a melting point of 330-450℃ and high-melting-point glass powder with a melting point of 500-800℃, and the mass ratio of the low-melting-point glass powder to the high-melting-point glass powder is 2-3:1-2.

8. The ablation-resistant ceramicized polypropylene material according to claim 7, characterized in that, The surface of the low-melting-point glass powder is grafted with an aminosilane coupling agent, and the surface of the high-melting-point glass powder is grafted with a long-chain alkylsilane coupling agent.

9. The ablation-resistant ceramicized polypropylene material according to claim 7, characterized in that, The low-melting-point glass powder is borosilicate glass powder; the high-melting-point glass powder is silicate glass powder and / or aluminosilicate glass powder.

10. The method for preparing the ablation-resistant ceramicized polypropylene material according to any one of claims 1 to 9, characterized in that, include: Preparation of polypropylene ceramic masterbatch: Weigh polypropylene, ceramic powder, glass powder and other additives according to the formula, mix them evenly and then melt-extrude and granulate them through a twin-screw extruder to obtain polypropylene ceramic masterbatch. Preparation of polypropylene glass fiber masterbatch: Weigh polypropylene, flame retardant, glass fiber and other additives according to the formula, mix them evenly and then melt extrude and granulate them through a twin-screw extruder to obtain polypropylene glass fiber masterbatch. Weigh out polypropylene ceramic masterbatch, polypropylene glass fiber masterbatch, antioxidant and polyphenylene sulfide according to the formula, mix them evenly and melt extrude and granulate them through a twin-screw extruder to obtain ablation-resistant ceramicized polypropylene material.

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