An alloy material, a preparation method and application thereof

Abstract

This invention relates to an alloy material, its preparation method, and its applications. The alloy material comprises the following components: PC resin, silicone PC resin, ABS resin, halogen-free flame retardant, flame retardant synergist masterbatch, compatibilizer, anti-dripping agent, antioxidant, and lubricant; the halogen-free flame retardant includes phosphorus-based flame retardants; the raw materials for preparing the flame retardant synergist masterbatch include nano-magnesium hydroxide and silicon-based synergists. This invention, through the design of the alloy material's components, provides a PC / ABS alloy material with excellent needle flame resistance, mechanical properties, processing fluidity, and high-temperature and high-humidity resistance (double 85 test).

Description

Technical Field

[0001] This invention relates to the field of polymer materials technology, and in particular to an alloy material, its preparation method, and its application. Background Technology

[0002] PC / ABS alloy material is an engineering plastic made by melt blending polycarbonate (PC) and acrylonitrile-butadiene-styrene copolymer (ABS). It combines the advantages of PC material, such as high temperature resistance, impact resistance, and dimensional stability, with the advantages of ABS material, such as easy processing and low cost. It has been widely used in electronic and electrical housings, automotive interior parts, charging pile components and other fields.

[0003] With the rapid development of industries such as electronics, automobiles, etc., safety standards for related products are becoming increasingly stringent, especially the needle flame test requirements. The needle flame test mainly simulates the impact of tiny flames generated inside the product due to a malfunction on the material, evaluating the flame retardant performance and flame spread characteristics of the material under the action of tiny flames. It is one of the important indicators for measuring the fire safety of materials, and its testing standards are mainly based on specifications such as GBT 5169.5-2020 and IEC 60695-11-5. With the increasing demand for lightweight materials, product dimensions are becoming smaller and thinner, and the requirements for materials are becoming more stringent. At present, although conventional PC / ABS alloy materials can pass ordinary flame retardant tests (such as UL94 1.0mm and 1.5mm V-0 rating), and can even achieve 0.8mm-V0 rating, in the needle flame test (especially for 1.0mm and 1.5mm thickness specifications), problems such as easy burn-through, excessively rapid flame spread, excessively long afterflame time, and dripping material igniting filter paper often occur, which cannot meet the requirements for use in high-end electronic appliances and key automotive components.

[0004] In existing technologies, brominated flame retardants are commonly used to improve the flame retardant properties of PC / ABS alloys. While this can enhance the flame retardant effect to some extent, brominated flame retardants release toxic and harmful gases and corrosive fumes during combustion, failing to meet environmental protection requirements and posing a threat to the environment and human health with long-term use. Although halogen-free flame retardant systems (such as phosphorus-based and silicon-based systems) are environmentally friendly, excessive addition of a single halogen-free flame retardant can severely affect the mechanical properties of PC / ABS alloys (such as reduced impact strength and tensile strength) and processing fluidity, making it difficult to consistently pass the needle flame resistance test. Furthermore, some halogen-free flame-retardant PC / ABS alloys also suffer from poor temperature resistance and hydrolysis resistance, and their flame retardant properties easily degrade in high-temperature and high-humidity environments, further limiting their application range.

[0005] Therefore, developing an environmentally friendly, halogen-free PC / ABS alloy material that can stably pass the needle flame test while also possessing excellent mechanical properties, processing performance, and high temperature and humidity resistance (double 85 test) and its preparation method has become a pressing technical challenge in this field. Summary of the Invention

[0006] To address the aforementioned technical problems, the present invention aims to provide an alloy material, its preparation method, and its applications. By designing the composition of the alloy material, a PC / ABS alloy material with excellent resistance to needle flame testing, mechanical properties, processing fluidity, and high-temperature and high-humidity resistance (dual 85 test) is provided. The preparation method of the alloy material is simple, convenient to operate, and highly efficient, facilitating large-scale industrial production. It effectively ensures the stability and consistency of product performance, and the preparation process releases no toxic or harmful gases, meeting environmental protection requirements.

[0007] To achieve this objective, the present invention adopts the following technical solution: In a first aspect, the present invention provides an alloy material comprising the following components: PC resin, silicone PC resin, ABS resin, halogen-free flame retardant, flame retardant synergist masterbatch, compatibilizer, anti-dripping agent, antioxidant, and lubricant; wherein the halogen-free flame retardant includes phosphorus-based flame retardant; and the raw materials for preparing the flame retardant synergist masterbatch include nano-magnesium hydroxide and silicon-based synergist.

[0008] In this invention, the phosphorus-based halogen-free flame retardant is environmentally friendly and non-toxic, does not release toxic halogen gases during combustion, and can form a dense char layer on the material surface, isolating oxygen and heat transfer, effectively preventing flame spread, and reducing dripping. It is one of the core components for passing the needle flame resistance test. Nano-magnesium hydroxide has the functions of flame retardancy, smoke suppression, and reducing combustion temperature, while the silicon-based synergist can promote char layer formation and improve the density and stability of the char layer. The two, together with the phosphorus-based halogen-free flame retardant, can significantly improve the needle flame resistance and smoke suppression effect of the alloy material, while improving the compatibility between the flame retardant and the resin matrix, solving the performance degradation problem caused by excessive addition of a single flame retardant. Compared with a single synergist, the flame retardant synergistic effect of the compound synergist is more significant, which can effectively improve the burn-through time of the needle flame test.

[0009] Preferably, the PC resin is prepared by the phosgene method.

[0010] Preferably, the PC resin comprises bisphenol A type polycarbonate.

[0011] Preferably, under test conditions of 300°C and 1.2 kg, the melt index of the PC resin is 8-15 g / 10 min, for example, it can be 9 g / 10 min, 10 g / 10 min, 11 g / 10 min, 12 g / 10 min, 13 g / 10 min or 14 g / 10 min, etc.

[0012] Preferably, the molecular weight of the PC resin is 20,000-30,000 g / mol, for example, it can be 22,000 g / mol, 24,000 g / mol, 25,000 g / mol, 26,000 g / mol or 28,000 g / mol.

[0013] In this invention, PC resin with melt flow index and molecular weight that meet the above requirements is used, which can ensure the high temperature resistance and mechanical strength of the alloy material, while also taking into account the processing fluidity. It has better compatibility with ABS resin, and phosgene PC can lay the foundation for improving the double 85 test and reduce the hydrolysis rate of the material.

[0014] Preferably, the raw materials for preparing the silicone PC resin include a combination of organosilicon monomers and PC resin monomers or PC resin prepolymers.

[0015] Preferably, the organosilicon monomer includes any one or a combination of at least two of methyltrichlorosilane, dimethyldichlorosilane, phenyltrichlorosilane, diphenyldichlorosilane, or methylphenyldichlorosilane.

[0016] Preferably, the PC resin monomer includes bisphenol A and diphenyl carbonate.

[0017] In this invention, organosilicon segments are introduced into the PC molecular structure to obtain silicone PC resin, thereby modifying the properties of PC resin. Silicone PC resin has good flexibility, hydrolysis resistance, corrosion resistance, oxidation resistance, and yellowing resistance.

[0018] Preferably, under test conditions of 300°C and 1.2 kg, the melt index of the silicone PC resin is 1-10 g / 10min, for example, it can be 2 g / 10min, 3 g / 10min, 4 g / 10min, 5 g / 10min, 6 g / 10min, 7 g / 10min, 8 g / 10min or 9 g / 10min, etc.

[0019] Preferably, the molecular weight of the silicone PC resin is 30,000-40,000 g / mol, for example, it can be 32,000 g / mol, 34,000 g / mol, 35,000 g / mol, 36,000 g / mol or 38,000 g / mol, etc.

[0020] Preferably, the silicon content in the silicone PC resin is 10%-20%, for example, it can be 12%, 14%, 15%, 16% or 18%, etc.

[0021] In this invention, a silicone PC resin with a melt index and molecular weight that meet the above requirements is used, which can ensure the alloy material's resistance to double 85 and mechanical strength, while also taking into account processing fluidity, and at the same time greatly improve the ability to perform double 85 testing.

[0022] Preferably, the ABS resin is prepared by a bulk method.

[0023] Preferably, after the alloy material is aged for 1000 hours at 85°C and 85% relative humidity, the notched impact strength retention rate is greater than 50%, for example, it can be 60%, 70%, 75%, 80% or 85%.

[0024] Preferably, the test standard for the notched impact strength is ASTM D256.

[0025] In this invention, blending ABS resin with PC resin significantly improves the processability and toughness of PC resin while avoiding the decline in flame retardant properties caused by excessive butadiene content, thus achieving a balance between mechanical and flame retardant properties. Compared to ABS synthesized by the emulsion method, bulk ABS exhibits better hydrolysis resistance, and the resulting alloy material shows better performance in the double 85 test and weather resistance test.

[0026] Preferably, under test conditions of 220°C and 10 kg, the melt index of the ABS resin is 5-15 g / 10min, for example, it can be 6 g / 10min, 7 g / 10min, 8 g / 10min, 9 g / 10min, 10 g / 10min, 11 g / 10min, 12 g / 10min, 13 g / 10min, or 14 g / 10min, etc.

[0027] Preferably, the phosphorus-based flame retardant includes any one or a combination of at least two of resorcinol bis(diphenyl phosphate) (RDP), bisphenol A bis(diphenyl phosphate) (BDP), hexaphenoxycyclotriphosphazene (HPTCP), or triphenyl phosphate (TPP), and more preferably a combination of bisphenol A bis(diphenyl phosphate), resorcinol bis(diphenyl phosphate), and hexaphenoxycyclotriphosphazene.

[0028] Preferably, the mass ratio of bisphenol A bis(diphenyl phosphate), resorcinol bis(diphenyl phosphate), and hexaphenoxycyclotriphosphazene is (4-6):(4-6):(1-3). Wherein, (4-6) in (4-6):(4-6):(1-3) can be, for example, 4.5, 4.8, 5, 5.3, or 5.5; and (1-3) in (4-6):(4-6):(1-3) can be, for example, 1.5, 1.8, 2, 2.3, or 2.5.

[0029] Preferably, the particle size of the nano-magnesium hydroxide is 50-100 nm, for example, it can be 60 nm, 70 nm, 75 nm, 80 nm or 90 nm.

[0030] Preferably, the silicon-based synergist includes methyl silicone oil and / or a silane coupling agent, and more preferably methyl silicone oil and a silane coupling agent.

[0031] Preferably, the mass ratio of the nano-magnesium hydroxide to the silane coupling agent is (3-6):1, for example, it can be 3.5:1, 4.0:1, 4.5:1, 5.0:1 or 5.5:1, etc.

[0032] Preferably, the mass ratio of the methyl silicone oil to the silane coupling agent is (0.8-1.2):1, for example, it can be 0.85:1, 0.9:1, 1:1, 1.1:1 or 1.15:1, etc.

[0033] Preferably, the silane coupling agent includes KH-550.

[0034] Preferably, the raw materials for preparing the flame retardant synergistic masterbatch also include polycarbonate (PC) powder.

[0035] Preferably, the mass ratio of PC powder to nano magnesium hydroxide is (2-9):1, for example, it can be 3:1, 4:1, 5:1, 6:1, 7:1 or 8:1, etc.

[0036] Preferably, the PC powder is prepared by the phosgene method.

[0037] Preferably, the preparation method of the flame-retardant synergistic masterbatch includes the following steps: Nano-magnesium hydroxide is placed in a pulverizer, which is operated at 25-35℃ (e.g., 26℃, 28℃, 30℃, 32℃, or 34℃) and 2500-3500 r / min (e.g., 2600 r / min, 2800 r / min, 3000 r / min, 3200 r / min, or 3400 r / min). Silane coupling agent KH-550 is added via a liquid spray device at 115-125 g / min (e.g., 116 g / min, 118 g / min, 120 g / min, 122 g / min, or 124 g / min). The powder is sprayed at a rate of g / min, etc. After spraying, methyl silicone oil is added through a spraying device. After all the powder is sprayed, the machine is run for 2-4 minutes (e.g., 2.5 minutes, 2.8 minutes, 3 minutes, 3.3 minutes, or 3.5 minutes, etc.) to coat magnesium hydroxide. The coated nano magnesium hydroxide and PC powder are mixed evenly, extruded and granulated, and dried to obtain the flame retardant synergistic masterbatch.

[0038] In this invention, running the machine for 2-4 minutes after all the methyl silicone oil and silane coupling agent have been sprayed allows the methyl silicone oil and silane coupling agent to fully coat the nano-magnesium hydroxide.

[0039] Preferably, the compatibilizer comprises styrene-maleic anhydride copolymer (SMA).

[0040] In this invention, the compatibilizer can effectively improve the compatibility between PC resin and ABS resin, reduce phase separation, improve the mechanical properties and processing stability of the alloy material, and at the same time promote the uniform dispersion of flame retardant in the resin matrix, avoid uneven flame retardant effect caused by flame retardant agglomeration, and ensure the stability of needle flame resistance.

[0041] Preferably, the content of maleic anhydride in the styrene-maleic anhydride copolymer is 8%-12%, for example, it can be 9%, 9.5%, 10%, 10.5% or 11%, etc.

[0042] Preferably, the anti-dripping agent comprises polytetrafluoroethylene micropowder.

[0043] In this invention, PTFE micro powder can form a fibrous network structure when the material is burning, preventing the melt from dripping and avoiding the dripping material from igniting the filter paper, thereby ensuring that the needle flame resistance test is passed.

[0044] Preferably, the particle size of the polytetrafluoroethylene micro powder is 1-10 μm, for example, it can be 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm or 9 μm, etc.

[0045] Preferably, the alloy material comprises the following components in parts by weight: 30-50 parts PC resin, 30-50 parts silicone PC resin, 5-15 parts ABS resin, 8-15 parts halogen-free flame retardant, 5-15 parts flame retardant synergistic masterbatch, 1-3 parts compatibilizer, 0.1-0.3 parts anti-dripping agent, 0.1-0.3 parts antioxidant, and 0.1-0.3 parts lubricant.

[0046] The PC resin can be, for example, 32 parts, 35 parts, 40 parts, 45 parts, or 48 parts by weight; the silicone PC resin can be, for example, 32 parts, 35 parts, 40 parts, 45 parts, or 48 parts by weight; the ABS resin can be, for example, 6 parts, 8 parts, 10 parts, 12 parts, or 14 parts by weight; the halogen-free flame retardant can be, for example, 9 parts, 10 parts, 11 parts, 12 parts, 13 parts, or 14 parts by weight; and the flame retardant synergistic masterbatch can be, for example, 6 parts, 8 parts, 10 parts, 12 parts, or 14 parts by weight. The compatibilizer may be present in parts by weight of, for example, 1.5 parts, 1.8 parts, 2 parts, 2.3 parts, or 2.5 parts; the anti-drip agent may be present in parts by weight of, for example, 0.12 parts, 0.15 parts, 0.2 parts, 0.25 parts, or 0.28 parts; the antioxidant may be present in parts by weight of, for example, 0.1-0.3 parts, such as 0.15 parts, 0.18 parts, 0.2 parts, 0.23 parts, or 0.25 parts; and the lubricant may be present in parts by weight of, such as 0.1-0.3 parts, such as 0.15 parts, 0.18 parts, 0.2 parts, 0.23 parts, or 0.25 parts.

[0047] In this invention, the amount of halogen-free flame retardant added must be strictly controlled. Too little will not meet the requirements for needle flame resistance, while too much will affect the mechanical properties and processability of the alloy.

[0048] In this invention, the amount of anti-dripping agent is crucial to the needle flame resistance performance. Too much addition will make the material easy to burn through in the needle flame test, while too little will not achieve the anti-dripping effect and will prevent the flame retardancy from reaching the V0 level.

[0049] Preferably, the alloy material further includes a toughening agent.

[0050] Preferably, the toughening agent is present in 4.5-8 parts by weight, for example, 5 parts, 5.5 parts, 6 parts, 6.5 parts or 7 parts, etc.

[0051] Preferably, the toughening agent comprises any one or a combination of at least two of methyl methacrylate-butadiene-styrene copolymer (MBS), ethylene-methyl acrylate-glycidyl methacrylate terpolymer (EMA), or acrylonitrile-butadiene rubber (NBR), and more preferably methyl methacrylate-butadiene-styrene copolymer and ethylene-methyl acrylate-glycidyl methacrylate terpolymer.

[0052] Preferably, the core-shell ratio of the methyl methacrylate-butadiene-styrene copolymer is (2-5):2, for example, it can be 2.5:2, 3:2, 3.5:2, 4:2 or 4.5:2, etc.

[0053] Preferably, the mass ratio of the methyl methacrylate-butadiene-styrene copolymer to the ethylene-methyl acrylate-glycidyl methacrylate terpolymer is (4-6):(0.5-2). Wherein, (4-6) can be, for example, 4.3, 4.5, 5, 5.5, or 5.8; and (0.5-2) can be, for example, 0.8, 1, 1.2, 1.5, or 1.8.

[0054] Preferably, the methyl methacrylate-butadiene-styrene copolymer is 4-6 parts by weight, for example, 4.3 parts, 4.5 parts, 5 parts, 5.5 parts or 5.8 parts, etc.

[0055] Preferably, the ethylene-methyl acrylate-glycidyl methacrylate terpolymer is present in parts by weight of 0.5-2 parts, for example, 0.8 parts, 1 part, 1.2 parts, 1.5 parts or 1.8 parts, etc.

[0056] In this invention, the addition of toughening agents effectively improves the impact resistance of PC / ABS alloy materials, compensates for the damage to alloy toughness caused by the addition of halogen-free flame retardants, and does not affect the flame retardant properties and processing fluidity of the alloy, ensuring that the alloy material meets the mechanical requirements of practical applications while possessing excellent flame retardant properties. The ethylene-methyl acrylate-glycidyl methacrylate terpolymer can also form a film on the material surface, improving the material's hydrolysis resistance and enhancing its performance in the double 85 test.

[0057] Preferably, the antioxidant comprises a compound of hindered phenolic antioxidants and phosphite antioxidants.

[0058] Preferably, the hindered phenolic antioxidant includes antioxidant 1010 and / or antioxidant 1076.

[0059] Preferably, the phosphite antioxidant includes antioxidant 168.

[0060] Preferably, the mass ratio of the hindered phenolic antioxidant to the phosphite antioxidant is 1:(0.8-1.2), for example, it can be 1:0.9, 1:0.95, 1:1, 1:1.05 or 1:1.1, etc.

[0061] In this invention, antioxidants can effectively prevent PC / ABS alloys from undergoing thermal oxidative degradation during melting and use, improve the thermal stability and service life of the material, avoid the decline in mechanical properties and flame retardant properties caused by thermal degradation, and ensure that the alloy material can still stably pass the needle flame resistance test during long-term use.

[0062] Preferably, the lubricant comprises butyl stearate and / or ethylene bis-stearamide, more preferably ethylene bis-stearamide (EBS).

[0063] In this invention, the lubricant can improve the fluidity of the alloy material during the melting process, reduce the friction between the material and the equipment, prevent the material from adhering to the equipment, and improve the processing efficiency, while not affecting the mechanical properties and flame retardant properties of the alloy, ensuring the stability of the preparation process and the consistency of product quality.

[0064] In a second aspect, the present invention provides a method for preparing an alloy material as described in the first aspect, the method comprising the following steps: The alloy material is obtained by mixing the components of the alloy material, melting and extruding them into granules.

[0065] Preferably, the process further includes a pretreatment step before mixing the components of the alloy material. The pretreatment method includes drying the PC resin, silicone PC resin, and ABS resin at 80-120℃ (e.g., 90℃, 95℃, 100℃, 105℃, or 110℃, etc.) for 4-6 hours (e.g., 4.5 hours, 4.8 hours, 5 hours, 5.3 hours, or 5.5 hours, etc.); and drying and pulverizing the halogen-free flame retardant, flame retardant synergist masterbatch, toughening agent, compatibilizer, anti-dripping agent, antioxidant, and lubricant, respectively.

[0066] In this invention, the PC resin, silicone PC resin, and ABS resin are dried separately to remove moisture from the raw materials, preventing defects such as bubbles and cracks from occurring during the melt processing, which would affect the mechanical and flame-retardant properties of the alloy material. The halogen-free flame retardant, flame-retardant synergistic masterbatch, toughening agent, compatibilizer, anti-dripping agent, antioxidant, and lubricant are dried and pulverized separately to ensure uniform particle size of each component, facilitating subsequent uniform mixing.

[0067] Preferably, the mixing is carried out in a high-speed mixer.

[0068] Preferably, the mixing speed is 1000-1500 r / min, for example, it can be 1100 r / min, 1200 r / min, 1250 r / min, 1300 r / min or 1400 r / min, etc.

[0069] Preferably, the mixing temperature is 25-35°C, for example, it can be 26°C, 28°C, 30°C, 32°C or 34°C.

[0070] In this invention, by controlling the rotation speed and temperature during the mixing process, it is avoided that excessive rotation speed will cause the material to heat up and degrade, while excessively low rotation speed will lead to uneven mixing.

[0071] Preferably, the mixing time is 1-3 min, for example, it can be 1.5 min, 1.8 min, 2 min, 2.3 min or 2.5 min, etc.

[0072] Preferably, the melt extrusion granulation is carried out in a twin-screw extruder.

[0073] Preferably, the screw speed of the twin-screw extruder is 400-500 r / min, for example, it can be 420 r / min, 440 r / min, 450 r / min, 460 r / min or 480 r / min, etc.

[0074] Preferably, the melt extrusion granulation includes the following steps: The mixed materials are added to a twin-screw extruder for melt blending, extrusion granulation, and segmented temperature control: feeding section 180-200℃ (e.g., 185℃, 188℃, 190℃, 193℃, or 195℃), melting section 240-260℃ (e.g., 245℃, 247℃, 250℃, 253℃, or 255℃), homogenization section 230-250℃ (e.g., 233℃, 235℃, 240℃, 243℃, or 245℃), and die head temperature 220-240℃ (e.g., 225℃, 228℃, 230℃, 233℃, or 235℃). After extrusion through the die head, the material is cooled to 20-30℃ in a water bath (e.g., 22℃, 24℃, 25℃, 26℃, or 28℃) before being pelletized by a pelletizer.

[0075] In this invention, during the melt blending process, each component reacts and disperses fully to form a PC / ABS alloy melt with a uniform structure.

[0076] In this invention, the extrusion temperature needs to be controlled within a specific range. Too high a temperature will lead to resin degradation, while too low a temperature will lead to insufficient melting and uneven mixing, affecting the alloy properties.

[0077] Preferably, the melt extrusion granulation process further includes a post-processing step, the post-processing method comprising: The granules after melt extrusion granulation are dried at 90-100℃ (e.g., 92℃, 94℃, 95℃, 96℃ or 98℃, etc.) for 2-4 hours (e.g., 2.5 hours, 2.8 hours, 3 hours, 3.2 hours or 3.5 hours, etc.) and then sieved by a screening machine.

[0078] In this invention, the dried granules can be directly used for injection molding, extrusion and other molding processes to prepare various products.

[0079] Thirdly, the present invention provides the application of the alloy material as described in the first aspect in electronic and electrical housings, automotive interior parts, or charging pile components.

[0080] Compared with the prior art, the present invention has at least the following beneficial effects: (1) The PC / ABS alloy material of the present invention adopts an environmentally friendly halogen-free flame retardant system composed of phosphorus-based halogen-free flame retardant and nano-magnesium hydroxide-silicon synergist. It does not release toxic and harmful gases and meets environmental protection requirements. At the same time, through the synergistic effect of each component, it can stably pass the needle flame resistance test (1.5mm thickness) specified in GBT 5169.5-2020 and IEC 60695-11-5 standards. After the flame is applied, there is no obvious spread, the afterflame time is ≤3 s, there is no phenomenon of dripping material igniting filter paper, and the product does not burn through. It has excellent flame retardant performance and solves the technical problem that conventional PC / ABS alloys are difficult to pass the needle flame resistance test. At the same time, it also takes into account the high temperature and high humidity resistance. After 85℃ / 85%RH×1000 h of damp heat aging, it can still maintain good flame retardant performance and mechanical properties, thus expanding its application range.

[0081] (2) By rationally matching the ratio of PC resin and ABS resin, and combining the synergistic effect of toughening agent and compatibilizer, this invention effectively compensates for the damage to the mechanical properties of the alloy caused by the addition of halogen-free flame retardant, so that the alloy material has excellent impact resistance (notched impact strength ≥600 J / m), tensile strength (≥55 MPa) and processing fluidity, and is convenient for molding and processing, which can meet the molding requirements of products of different specifications. It solves the problem that the mechanical properties and flame retardant properties of existing halogen-free flame retardant PC / ABS alloys are difficult to balance, and at the same time avoids the problems of processing difficulties and unstable performance caused by excessive addition of a single flame retardant.

[0082] (3) The preparation method of the present invention is simple, convenient to operate, and has high production efficiency. The parameters of each step are reasonably controlled, which makes it easy to carry out large-scale industrial production. It can effectively ensure the stability and consistency of product performance and has a low production cost. Compared with the high-end flame-retardant PC / ABS alloy in the prior art, it has a higher cost performance and is suitable for large-scale promotion and application.

[0083] (4) The alloy material of the present invention can be widely used in fields with high requirements for needle flame resistance, flame retardancy and mechanical properties, such as electronic and electrical appliance housings, automotive parts, communication equipment, and charging pile components. It has broad market application prospects, conforms to the current development trend of environmental protection, high efficiency and high performance of polymer materials, can meet the industry's demand for safe and environmentally friendly materials, and has significant economic and social benefits. Detailed Implementation

[0084] To facilitate understanding of the present invention, the following embodiments are provided. Those skilled in the art should understand that these embodiments are merely illustrative and should not be construed as limiting the scope of the invention.

[0085] In the following examples, all raw materials used in the preparation were commercially available conventional products: PC resin: Bisphenol A type, melt index (300℃, 1.2 kg) 10 g / 10min, molecular weight 25000 g / mol, purchased from Wanhua Chemical, grade 1105.

[0086] Silicone PC resin: purchased from Wanhua Chemical, grade S2060.

[0087] ABS resin: melt index (220℃, 10 kg) 10 g / 10min, purchased from Shanghai Gaoqiao, grade 3513.

[0088] Halogen-free flame retardants: RDP, BDP, HPTCP, commercially available.

[0089] Flame retardant synergistic masterbatch: self-made, the preparation method of the flame retardant synergistic masterbatch includes the following steps: 500 g of nano-magnesium hydroxide was placed in a pulverizer, which was run at 3000 r / min at 30°C. 100 g of silane coupling agent KH-550 was added through a liquid spraying device at a speed of 120 g / min. After spraying, 100 g of methyl silicone oil was added through the spraying device. After all the spraying was completed, the machine was run for another 3 minutes to coat the magnesium hydroxide. The coated nano-magnesium hydroxide and 2500 g of PC powder were mixed evenly, extruded and granulated, and dried to obtain the flame retardant synergistic masterbatch.

[0090] Nano magnesium hydroxide (80 nm particle size) and methyl silicone oil were purchased from Dow Corning silicone oil, brand name PMX200; silane coupling agent KH-550 was commercially available; PC powder was purchased from Wanhua Chemical, brand name 2220.

[0091] Toughening agent: MBS, commercially available, purchased from Rohm and Haas, brand name EXL-2690.

[0092] Toughening agent: EMA, commercially available, purchased from Arkema, brand name 29MA03T.

[0093] Compatibilizer: SMA, commercially available, purchased from Shanghai Huawen, brand name SMA-725.

[0094] Anti-dripping agent: PTFE micro powder, commercially available.

[0095] Antioxidants: Antioxidant 1010 and Antioxidant 168, commercially available; purchased from BASF.

[0096] Lubricant: EBS, commercially available, Kao EB-FF.

[0097] Example 1 An alloy material and its preparation method are disclosed. The alloy material comprises the following components: phosgene-based PC resin, silicone PC resin, bulk-processed ABS resin, halogen-free flame retardant (RDP:BDP:HPTCP=5:5:3), flame retardant synergist masterbatch, toughening agent (MBS), toughening agent (EMA), compatibilizer (SMA), anti-dripping agent (PTFE), antioxidant (1010:168=1:1), and lubricant (EBS). The amounts of each component are shown in Table 1.

[0098] The preparation method includes the following steps: (1) Raw material pretreatment: PC resin is dried at 120℃ for 4 h and ABS resin is dried at 85℃ for 4 h; halogen-free flame retardant, flame retardant synergist masterbatch, toughening agent, compatibilizer, anti-dripping agent, antioxidant and lubricant are dried and pulverized respectively to ensure uniform particle size.

[0099] (2) Mixing and batching: Add the pretreated components to a high-speed mixer and mix for 2 minutes at a speed of 1200 r / min and a temperature of 30℃ to obtain a mixture.

[0100] (3) Melt extrusion granulation: The mixture is added to a twin-screw extruder with a screw speed of 450 r / min. The extrusion temperature is controlled in stages: 190℃ for the feeding section, 250℃ for the melting section, 240℃ for the homogenization section, and 230℃ for the die head. After extrusion, the mixture is cooled to 25℃ in a water tank and then granulated to obtain alloy particles.

[0101] (4) Drying and sieving: The alloy particles are dried at 95°C for 3 h, and impurities and unqualified particles are removed by sieving to obtain the alloy material.

[0102] Example 2 An alloy material and its preparation method are disclosed. The composition of the alloy material differs from that of Example 1 only in the amount of each component in Table 1.

[0103] The difference between the preparation method and Example 1 is only that: the rotation speed in step (2) is 1000 r / min, the mixing time in step (2) is 1 min, the screw speed of the twin-screw extruder in step (3) is 500 r / min, and the extrusion temperature in step (3) is 180℃ for the feeding section, 240℃ for the melting section, 230℃ for the homogenization section, and 220℃ for the die head.

[0104] Example 3 An alloy material and its preparation method are disclosed. The composition of the alloy material differs from that of Example 1 only in the amount of each component in Table 1.

[0105] The difference between the preparation method and Example 1 is only that: the rotation speed in step (2) is 1500 r / min, the mixing time in step (2) is 3 min, the screw speed of the twin-screw extruder in step (3) is 400 r / min, and the extrusion temperature in step (3) is 200℃ for the feeding section, 260℃ for the melting section, 250℃ for the homogenization section, and 240℃ for the die head.

[0106] Example 4 An alloy material and its preparation method are disclosed, which differ from Example 1 only in that no anti-dripping agent is added to the alloy material components, and the specific dosage is shown in Table 1.

[0107] Example 5 An alloy material and its preparation method are disclosed, which differ from Example 1 only in that the weight of the anti-dripping agent in the alloy material is increased from 0.2 parts to 0.5 parts, and the specific dosage is shown in Table 1.

[0108] Example 6 An alloy material and its preparation method are disclosed, which differ from Example 1 only in that the alloy material does not contain added silicone PC resin, and the weight of the PC resin is 80 parts, as shown in Table 1.

[0109] Example 7 An alloy material and its preparation method differ from Example 1 only in that the bulk ABS resin in the alloy material components is replaced with the same weight fraction of emulsion ABS resin, and the specific amounts are shown in Table 1.

[0110] Comparative Example 1 An alloy material and its preparation method are disclosed, which differ from Example 1 only in that the alloy material components do not contain flame-retardant synergistic masterbatch, and the specific dosage is shown in Table 1.

[0111] Comparative Example 2 An alloy material and its preparation method differ from Example 1 only in that the type and amount of halogen-free flame retardant in the alloy material components are different, and the specific amounts are shown in Table 1.

[0112] In Table 1, the amount of each component is expressed in parts by weight.

[0113] Table 1 Test methods (1) Needle flame resistance test: conducted in accordance with GBT 5169.5-2020 standard, with a sample thickness of 1.5 mm.

[0114] (2) Flame retardant performance: conducted in accordance with UL94 standard, with a test sample thickness of 1.0 mm.

[0115] (3) Mechanical properties: tensile strength is tested according to American standard ASTM D638, and notched impact strength is tested according to American standard ASTM D256.

[0116] (4) Processing fluidity: Melt index was determined according to the American standard ASTM D1238 (PC resin test conditions 300℃, 1.2 kg; ABS resin test conditions 220℃, 10 kg; alloy material test conditions 250℃, 2.16 kg).

[0117] (5) High temperature and high humidity (double 85) performance test: After aging the sample in an 85℃ / 85%RH constant temperature and humidity chamber for 1000h, test its flame retardant performance and mechanical property retention rate.

[0118] The test results are shown in Table 2.

[0119] Table 2 Note: In Table 2, the needle flame test standard is based on the product's burn-through time. Burn-through within 60 seconds is considered unqualified, while burn-through exceeding 60 seconds is considered qualified. The flame retardant level is 1.0-V0, which is considered qualified. The notch impact strength retention rate after the double 85 test (1000H) must be greater than 50%.

[0120] The test results show that: (1) As can be seen from Examples 1-3, the present invention provides a PC / ABS alloy material with excellent needle flame resistance, mechanical properties, processing fluidity, and high temperature and humidity resistance (double 85 test) by designing the composition of the alloy material. The alloy material can stably pass the 1.0 mm flame retardant test to reach the V-0 level, and the 1.5 mm thickness can meet the requirements of the needle flame resistance test. At the same time, it has excellent mechanical properties and processing fluidity, and high performance retention rate after double 85 aging.

[0121] (2) A comparison of Examples 1 and Examples 4-7 shows that the present invention improves the performance of the alloy material by further limiting the amount of each component in the alloy material and the preparation method. Specifically, Example 4 did not add an anti-dripping agent, resulting in a decrease in flame retardant performance; Example 5 used too much anti-dripping agent, leading to a deterioration in needle flame resistance; Example 6 used too much PC resin, resulting in a decrease in all properties; and Example 7 did not use ABS resin prepared by the bulk method, resulting in a significant decrease in notched impact strength after the double 85 test.

[0122] (3) As can be seen from the comparison between Example 1 and Comparative Examples 1-2, the absence of either the flame retardant synergistic masterbatch or the compound halogen-free flame retardant of the present invention will cause a decrease in the performance of the alloy material. Specifically, Comparative Example 1 did not add the flame retardant synergistic masterbatch, and its needle flame resistance decreased; Comparative Example 2 did not add the compound halogen-free flame retardant, and its notched impact strength decreased after the double 85 test.

[0123] In summary, this invention effectively improves the needle flame resistance, mechanical properties, and high temperature and humidity resistance of PC / ABS alloys through the rational combination and synergistic effect of the components in the alloy material, achieving a balance of multiple properties.

[0124] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. An alloy material, characterized in that, The alloy material comprises the following components: PC resin, silicone PC resin, ABS resin, halogen-free flame retardant, flame retardant synergist masterbatch, compatibilizer, anti-dripping agent, antioxidant, and lubricant; the halogen-free flame retardant includes phosphorus-based flame retardant; the raw materials for preparing the flame retardant synergist masterbatch include nano-magnesium hydroxide and silicon-based synergist.

2. The alloy material according to claim 1, characterized in that, The PC resin was prepared by the phosgene method; Preferably, the PC resin comprises bisphenol A type polycarbonate; Preferably, under test conditions of 300°C and 1.2 kg, the melt index of the PC resin is 8-15 g / 10 min; Preferably, the molecular weight of the PC resin is 20,000-30,000 g / mol; Preferably, the raw materials for preparing the silicone PC resin include a combination of organosilicon monomers and PC resin monomers or PC resin prepolymers; Preferably, the organosilicon monomer includes any one or a combination of at least two of methyltrichlorosilane, dimethyldichlorosilane, phenyltrichlorosilane, diphenyldichlorosilane, or methylphenyldichlorosilane; Preferably, the PC resin monomer includes bisphenol A and diphenyl carbonate; Preferably, under test conditions of 300°C and 1.2 kg, the melt index of the silicone PC resin is 1-10 g / 10 min; Preferably, the molecular weight of the silicone PC resin is 30,000-40,000 g / mol; Preferably, the silicon content in the silicone PC resin is 10%-20%; Preferably, the ABS resin is prepared by a bulk method; Preferably, under test conditions of 220°C and 10 kg, the melt index of the ABS resin is 5-15 g / 10 min.

3. The alloy material according to claim 1 or 2, characterized in that, The phosphorus-based flame retardant includes any one or a combination of at least two of resorcinol bis(diphenyl phosphate), bisphenol A bis(diphenyl phosphate), hexaphenoxycyclotriphosphazene, or triphenyl phosphate, and is more preferably a combination of bisphenol A bis(diphenyl phosphate), resorcinol bis(diphenyl phosphate), and hexaphenoxycyclotriphosphazene. Preferably, the mass ratio of bisphenol A bis(diphenyl phosphate), resorcinol bis(diphenyl phosphate), and hexaphenoxycyclotriphosphazene is (4-6):(4-6):(1-3); Preferably, the particle size of the nano-magnesium hydroxide is 50-100 nm; preferably, the silicon-based synergist includes methyl silicone oil and / or a silane coupling agent, more preferably methyl silicone oil and a silane coupling agent; Preferably, the mass ratio of the nano-magnesium hydroxide to the silane coupling agent is (3-6):1; Preferably, the mass ratio of the methyl silicone oil to the silane coupling agent is (0.8-1.2):1; Preferably, the silane coupling agent includes KH-550.

4. The alloy material according to any one of claims 1-3, characterized in that, The compatibilizer includes a styrene-maleic anhydride copolymer; Preferably, the content of maleic anhydride in the styrene-maleic anhydride copolymer is 8%-12%; Preferably, the anti-dripping agent comprises polytetrafluoroethylene micropowder; Preferably, the particle size of the polytetrafluoroethylene micro powder is 1-10 μm.

5. The alloy material according to any one of claims 1-4, characterized in that, The alloy material comprises the following components in parts by weight: 30-50 parts PC resin, 30-50 parts silicone PC resin, 5-15 parts ABS resin, 8-15 parts halogen-free flame retardant, 5-15 parts flame retardant synergistic masterbatch, 1-3 parts compatibilizer, 0.1-0.3 parts anti-dripping agent, 0.1-0.3 parts antioxidant, and 0.1-0.3 parts lubricant.

6. The alloy material according to any one of claims 1-5, characterized in that, The alloy material also includes toughening agents; Preferably, the toughening agent is present in 4.5-8 parts by weight; Preferably, the toughening agent comprises any one or a combination of at least two of methyl methacrylate-butadiene-styrene copolymer, ethylene-methyl acrylate-glycidyl methacrylate terpolymer, or acrylonitrile-butadiene rubber, and more preferably methyl methacrylate-butadiene-styrene copolymer and ethylene-methyl acrylate-glycidyl methacrylate terpolymer. Preferably, the core-shell ratio of the methyl methacrylate-butadiene-styrene copolymer is (2-5):2; Preferably, the mass ratio of the methyl methacrylate-butadiene-styrene copolymer to the ethylene-methyl acrylate-glycidyl methacrylate terpolymer is (4-6):(0.5-2); Preferably, the methyl methacrylate-butadiene-styrene copolymer is present in 4-6 parts by weight; Preferably, the ethylene-methyl acrylate-glycidyl methacrylate terpolymer is 0.5-2 parts by weight; Preferably, the antioxidant comprises a compound of hindered phenolic antioxidants and phosphite antioxidants; Preferably, the hindered phenolic antioxidant includes antioxidant 1010 and / or antioxidant 1076; Preferably, the phosphite antioxidant includes antioxidant 168; Preferably, the mass ratio of the hindered phenolic antioxidant to the phosphite antioxidant is 1:(0.8-1.2); Preferably, the lubricant comprises butyl stearate and / or ethylene bis-stearamide, more preferably ethylene bis-stearamide.

7. A method for preparing an alloy material as described in any one of claims 1-6, characterized in that, The preparation method includes the following steps: The alloy material is obtained by mixing the components of the alloy material, melting and extruding them into granules.

8. The preparation method according to claim 7, characterized in that, The process of mixing the components of the alloy material includes a pretreatment step, which includes drying the PC resin, silicone PC resin and ABS resin at 80-120℃ for 4-6 hours; and drying and pulverizing the halogen-free flame retardant, flame retardant synergist masterbatch, toughening agent, compatibilizer, anti-dripping agent, antioxidant and lubricant respectively.

9. The preparation method according to claim 7 or 8, characterized in that, The mixing is carried out in a high-speed mixer; Preferably, the mixing speed is 1000-1500 r / min; Preferably, the mixing temperature is 25-35°C; Preferably, the mixing time is 1-3 minutes; Preferably, the melt extrusion granulation is carried out in a twin-screw extruder; Preferably, the screw speed of the twin-screw extruder is 400-500 r / min.

10. The application of an alloy material as described in any one of claims 1-6 in electronic and electrical housings, automotive interior parts, or charging pile components.

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