Preparation method of optical PC flame-retardant weather-resistant antistatic material

Abstract

The invention belongs to the technical field of high polymer materials, and discloses a preparation method of an optical PC flame-retardant weather-resistant antistatic material, and the preparation method comprises the following specific steps: S1: selecting materials to synthesize a flame-retardant antistatic agent, S2: doping a flame retardant with PC for covalent connection, and S3: molding the mixture to prepare a target PC material. According to the invention, by integrating the core information of'raw material-process-performance-application 'of the high polymer material, the logic fracture caused by step dispersion is avoided; the full view of the rapid high polymer material grasp high polymer material technology for readers is as follows: the high polymer material S1 synthesizes 1-5 high polymer material parts of a flame-retardant antistatic agent containing double functional groups from a specific raw material, which is the basis of subsequent reaction; the high polymer material S2 and the high polymer material PC are doped according to 3-5 parts of the high polymer material, and the key effects of realizing uniform arrangement of groups and stabilizing carbonate groups are achieved through covalent bond connection.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of high polymer materials, and particularly relates to a preparation method of optical PC flame-retardant weather-resistant antistatic material. BACKGROUND

[0002] The preparation method of the optical PC flame-retardant weather-resistant antistatic material refers to a technical scheme for preparing a composite high polymer material PC high polymer material with four core performances of high polymer materials, i.e., optical transparency, flame retardation, weather resistance and antistaticity, by taking high-transparency optical-grade polycarbonate (PC) resin as a core base material and through precise compounding of functional modification components and optimization of a process. In the prior art, the first contradiction in preparing the material is the conflict between the functional components and the optical performance. In the halogen-free flame retardant, phosphorus needs a large amount to meet the standard, but the refractive index difference affects the light transmission; the silicon has poor compatibility with the PC matrix, which also leads to the decrease of the light transmission; the sulfonate has good transparency, but it is difficult to meet the flame-retardant requirement of thin-walled parts when used alone. In terms of the antistatic agent, the small molecule type has slow migration in the PC matrix, which makes the surface resistance unstable; the high molecule type needs a certain amount to form a stable conductive network, but the refractive index difference will reduce the light transmission. In the weather-resistant agent, the benzotriazole type is easy to decompose at high temperature, and the basic group of the hindered amine type light stabilizer will react with the acidic flame retardant, resulting in the failure of the weather resistance. There are also bottlenecks in the process, such as the difficulty in dispersing the nanoscale conductive filler in the melt blending, the separation of the flame retardant and the antistatic agent, and the influence on the strength of the material. High-temperature processing will lead to the degradation of PC, and some flame retardants may also decompose in advance, and the effect of the antioxidant will also decrease at high temperature. The poor interfacial compatibility is also prominent, the silicon flame retardant has weak combination with PC, and is easy to separate in the humid heat environment; the antistatic agent and the weather-resistant agent may also have chemical conflict, resulting in the decrease of the performance of both. SUMMARY

[0003] The application aims to provide a preparation method of optical PC flame-retardant weather-resistant antistatic material to solve the problems in the background.

[0004] In order to achieve the above-mentioned purpose, the application provides the following technical scheme: a preparation method of optical PC flame-retardant weather-resistant antistatic material, and the specific steps of the preparation method are as follows: S1: selecting materials to synthesize a flame-retardant antistatic agent: Halogen-free flame retardant perfluorobutyl sulfonate, polyvinyl alcohol and bisphenol A type compound are selected as auxiliary synergistic materials to prepare a flame-retardant antistatic agent containing halogen-free transparent elements through cross-linking synthesis reaction; the flame-retardant antistatic agent has double functional groups of sulfonic acid group and hydroxyl group, and the total amount of the flame-retardant antistatic agent is controlled to be 1-5 parts to avoid the opacity of the material caused by excessive flame-retardant antistatic agent; S2: flame-retardant agent is mixed with PC to be covalently connected: The flame-retardant antistatic agent prepared in S1 is added into the polycarbonate unit in a mass ratio of 3-5 parts, and the PC macromolecule is connected to the sulfonic acid group and the hydroxyl group in the flame-retardant antistatic agent through reaction to form a covalent bond, so that the sulfonic acid group and the hydroxyl group are uniformly arranged in the PC molecular chain, and the in-situ unchanged characteristic of the "carbonate" core group in the PC molecular chain is maintained during the connection process, and the scattering of the molecular chain to light is reduced; S3: molding the mixture to prepare the target PC material: The mixture obtained in S2 is subjected to molding processing to prepare an optical PC flame-retardant weather-resistant antistatic material; the material needs to meet the following requirements: the light transmittance is 88%-90%, the flame-retardant performance meets the UL94-V0 level, the surface resistance is 1.0 x 10 8 Ω-1.0 x 10 11 Ω, and there is no migration and precipitation of the flame-retardant antistatic agent on the surface of the material; at the same time, the benzene ring in the PC molecular chain and the hydroxyl structure of PVA form enhanced linkage to ensure that there is no cracking in the material, so that the material has excellent impact resistance, weather resistance and heat resistance, and meets the industrial application requirements.

[0005] Preferably, the bisphenol A type compound in S1 is specifically a bisphenol A type polycarbonate oligomer, and the number average molecular weight is strictly controlled in the range of 500-1000; and the mass ratio of the oligomer in the auxiliary synergistic material composed of the halogen-free flame retardant perfluorobutyl sulfonate, polyvinyl alcohol and itself is maintained at 15%-25%. This parameter setting can adapt to the requirements of the cross-linking reaction, help generate the flame-retardant antistatic agent containing sulfonic acid group and hydroxyl group, and provide protection for the subsequent compatible combination with the PC unit and the maintenance of the high transparency core performance of the material.

[0006] Preferably, the cross-linking reaction in S1 uses deionized water as the reaction medium, and the key conditions are strictly controlled: the reaction temperature is controlled at 70-90℃, the stirring rate is set at 200-300 r / min, and the reaction is continuously carried out for 3-5 h to ensure sufficient reaction. After the reaction is completed, the product is treated by a spray drying process, in which the inlet air temperature is controlled at 180-200℃ and the outlet air temperature is 80-90℃. Finally, the flame-retardant antistatic agent powder with uniform particle size in the range of 5-10 μm is prepared, which lays a foundation for the subsequent compatible combination with the PC unit.

[0007] Preferably, the PC unit used in S2 is an optical grade transparent PC resin, which needs to meet the following key indicators: the light transmittance is greater than or equal to 92% when the thickness is 3 mm, and the water content in the resin is less than or equal to 0.02%, so as to avoid the influence of water on the subsequent reaction and the optical performance of the material. In order to further ensure the compatibility and product quality, the optical grade transparent PC resin needs to be subjected to vacuum drying treatment at 120-130℃ before being mixed with the flame-retardant antistatic agent prepared in S1, and the drying time is controlled at 4-6 h.

[0008] Preferably, the reaction of the PC macromolecule in S2 with the flame-retardant antistatic agent is completed by using a double-screw extruder, and the equipment parameters need to be strictly set: the temperature of the feeding section is controlled at 220-240 DEG C, the temperature of the melting section is set at 260-280 DEG C, the temperature of the homogenizing section is kept at 250-270 DEG C, the temperature of the head is adjusted to 240-260 DEG C, and the screw speed is controlled at 250-350 r / min; the combination of the parameters can ensure that the PC and the flame-retardant antistatic agent are fully mixed and melted, promote the formation of stable covalent bonds between the functional groups, and provide process protection for the subsequent standard light transmittance and flame-retardant properties of the material.

[0009] Preferably, the weather resistance of the optical PC flame-retardant weather-resistant antistatic material needs to be verified by specific tests: QUV aging test is used, UVB-313 lamp is used as the irradiation source, the irradiation time is set to 2000h, the condensation time is set to 168h, and after the test, the material needs to meet two core indicators: the yellowing index is less than or equal to 2.0, and the optical transparency is not significantly affected; and the surface resistance change amplitude is less than or equal to 2 orders of magnitude, and the stable antistatic performance is maintained.

[0010] Preferably, the heat resistance of the material needs to meet double requirements: one is that the heat distortion temperature is greater than or equal to 150 DEG C under the condition of 0.45 MPa pressure, so that the material is not easy to deform in a medium-high temperature environment; and the other is that after 1000h of hot air aging at 150 DEG C, the impact strength retention rate of the material is greater than or equal to 90%, and the light transmittance retention rate is greater than or equal to 95%, which can effectively resist the damage of long-term high temperature to the mechanical properties and optical properties; the heat resistance performance can adapt to various high-temperature application scenarios, and further supports the industrialization practical value of the material.

[0011] Preferably, in addition to the halogen-free flame retardant perfluorobutyl sulfonate, polyvinyl alcohol and bisphenol A compound, the auxiliary synergistic material in S1 also needs to add 0.5-1 parts of silane coupling agent, which needs to be put into the reaction system together with the perfluorobutyl sulfonate and PVA at the initial stage of the crosslinking reaction, and the core function is to optimize the interfacial bonding state of the flame-retardant antistatic agent and the PC unit prepared subsequently.

[0012] Preferably, the impact resistance of the material needs to strictly meet specific test standards: according to GB / T1843-2021 standard detection, the Izod notched impact strength is greater than or equal to 8kJ / m² at 23 DEG C normal temperature environment; after the low temperature test at-30 DEG C, the impact strength still needs to be greater than or equal to 6kJ / m², and the material has no obvious cracking phenomenon, and the impact resistance is benefited from the enhanced link formed by the benzene ring in the PC molecular chain and the hydroxyl group in PVA.

[0013] The beneficial effects of the present application are as follows: 1、The present application integrates the core information of high polymer material "raw material-process-performance-application", avoids the logical break caused by dispersed steps, and enables the reader to quickly grasp the overall picture of high polymer material technology: S1 is clear that the specific raw material is used to synthesize high polymer material 1-5, and the high polymer material contains a double functional flame-retardant antistatic agent, which is the basis for subsequent reaction; S2 is clear that the high polymer material is mixed with high polymer material 3-5, and the key role of the group is achieved by covalent bond connection to realize the stable carbonate group; S3 can also present the light transmittance, flame-retardant grade, surface resistance index, and impact resistance, weather resistance and other performance advantages of the high polymer material after molding. This integrated presentation can reduce information search cost, strengthen the technical correlation between steps, facilitate technical exchange, document archiving or industrialization guidance, enable the audience to efficiently understand the preparation logic and material value, and help technology landing and popularization.

[0014] 2、The optical PC flame-retardant weather-resistant antistatic material preparation method and the material itself have multiple benefits: from the preparation logic, the three-step process S1 synthesizes flame-retardant antistatic agent, S2 covalently connects, and S3 is clear and controllable, such as S1 specifies the molecular weight of bisphenol A oligomer, reaction temperature, speed and time, S2 accurately sets the double screw extrusion parameters, which can ensure full reaction and uniform mixing, reduce production fluctuations, and adapt to industrial batch production; from the material performance, through raw material selection and process optimization, multifunctional integration can be achieved, not only the light transmittance reaches 88%-90%, the flame-retardant performance meets UL94-V0 level, the surface resistance is 1.0x10 8 ~1.0x10 11 Ohm without agent migration and precipitation, but also has excellent weather resistance, heat resistance and impact resistance, effectively solving the problem of single function or performance conflict of traditional materials; from the application value, the material can adapt to multiple scenes of electronics, optics and outdoor building materials, can avoid performance failure caused by environment or external force, reduce use loss and prolong service life, fully meet the high demand of industrialization for material comprehensive performance and durability. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 The present application is a whole process schematic diagram of the preparation method. DETAILED DESCRIPTION

[0016] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor belong to the scope of protection of the present application.

[0017] As Figure 1As shown, the embodiment of the present application provides a preparation method of optical PC flame-retardant weather-resistant antistatic material, and the specific steps of the preparation method are as follows: S1: Selecting materials to synthesize flame-retardant antistatic agent: Halogen-free flame retardant perfluorobutyl sulfonate, polyvinyl alcohol (PVA) and bisphenol A compound are selected as auxiliary synergistic materials, and a halogen-free transparent element-containing flame-retardant antistatic agent is prepared through cross-linking synthesis reaction; the flame-retardant antistatic agent has double functional groups of sulfonic acid group (-SO3H) and hydroxyl group (-OH), and the total amount of the flame-retardant antistatic agent is controlled to be 1-5 parts to avoid opacity of the material due to excessive flame-retardant antistatic agent; S2: Flame-retardant agent is mixed with PC to form covalent bond: According to the mass fraction of 3-5 parts, the flame-retardant antistatic agent prepared in S1 is mixed into the polycarbonate (PC) unit, and the sulfonic acid group and the hydroxyl group in the flame-retardant antistatic agent are connected to the PC macromolecule through reaction to form a covalent bond, so that the sulfonic acid group and the hydroxyl group are uniformly arranged in the PC molecular chain, and the in-situ unchanged characteristic of the "carbonate" core group (-O-(C=O)-O-) in the PC molecular chain is maintained during the connection process, thereby reducing the scattering of the molecular chain to light; S3: Forming the target PC material by mixing the mixture: The mixture obtained in S2 is subjected to forming processing to obtain the optical PC flame-retardant weather-resistant antistatic material; the material needs to meet the following requirements: the light transmittance is 88%-90%, the flame-retardant performance meets the UL94-V0 level, the surface resistance is 1.0×10 8 Ω-1.0×10¹¹Ω, and there is no migration and precipitation of the flame-retardant antistatic agent on the surface of the material; at the same time, the benzene ring in the PC molecular chain and the hydroxyl structure of PVA form enhanced linkage to ensure that there is no cracking in the material, so that the material has excellent impact resistance, weather resistance and heat resistance, and meets the industrial application requirements.

[0018] In S1, the bisphenol A compound is specifically bisphenol A polycarbonate oligomer, the number average molecular weight of which is strictly controlled in the range of 500-1000, and the mass fraction of the oligomer in the auxiliary synergistic material composed of halogen-free flame retardant perfluorobutyl sulfonate, polyvinyl alcohol (PVA) and itself is maintained at 15%-25%, which can meet the requirements of cross-linking synthesis reaction and help to generate the flame-retardant antistatic agent containing sulfonic acid group and hydroxyl group, and at the same time, provide protection for the subsequent compatible combination with the PC unit and the maintenance of the high transparency core performance of the material.

[0019] The bisphenol compound less than or equal to A less than or equal to type is set as a polycarbonate oligomer with a number average molecular weight of less than or equal to 500-1000 less than or equal to, and accounts for less than or equal to 15%-25% of the auxiliary synergistic material. This setting can accurately adapt to the needs of the copolymerization reaction, help generate a flame-retardant antistatic agent containing sulfonic acid groups and hydroxyl groups, and provide key functional groups for subsequent reactions. At the same time, this parameter can improve the compatibility of the flame-retardant antistatic agent with less than or equal to PC less than or equal to units, avoid uneven dispersion due to poor compatibility, and also maintain the high transparency core performance of the material, ensuring that the final product meets the light transmittance standard, laying the foundation for the core performance of the optical less than or equal to PC less than or equal to flame-retardant weather-resistant antistatic material to be qualified, and supporting industrial application.

[0020] In the S1, the copolymerization reaction is carried out in deionized water as the reaction medium, and the key conditions are strictly controlled: the reaction temperature is controlled at 70-90°C, the stirring rate is set at 200-300 r / min, and the reaction is continued for 3-5 h to ensure sufficient reaction. After the reaction is completed, the product is treated by spray drying process, wherein the inlet air temperature is controlled at 180-200°C and the outlet air temperature is 80-90°C, and finally the flame-retardant antistatic agent powder with uniform particle size in the range of 5-10 μm is obtained, laying the foundation for subsequent compatible combination with PC units.

[0021] Deionized water as the medium can avoid impurity interference in the reaction and ensure product purity; 70-90°C temperature, 200-300 r / min less than or equal to stirring and less than or equal to 3-5 h less than or equal to reaction time can ensure that the raw materials are fully reacted to generate a flame-retardant antistatic agent with complete functional groups. Subsequent spray drying with an inlet air temperature of less than or equal to 180-200°C and an outlet air temperature of less than or equal to 80-90°C can make the product dry uniformly and not damage the structure, and finally obtain a powder with a uniform particle size of less than or equal to 5-10 μm. This lays the foundation for subsequent uniform mixing and stable compatible combination with less than or equal to PC less than or equal to units, and helps to achieve covalent bond connection and material core performance standards.

[0022] In the S2, the PC unit used is an optical grade transparent PC resin, which needs to meet the key indicators: light transmittance greater than or equal to 92% at a thickness of 3 mm, and water content in the resin less than or equal to 0.02%, to avoid the influence of water on subsequent reactions and material optical properties. To further ensure compatibility and product quality, before mixing with the flame-retardant antistatic agent prepared in S1, the optical grade transparent PC resin needs to be vacuum dried at 120-130°C for 4-6 h. This can effectively remove the residual water in the resin, laying the foundation for subsequent covalent bond connection and stable material performance.

[0023] Optical grade PC resin with transmittance ≥ 92%, moisture ≤ 0.02%, pre-processed by vacuum drying at 120-130°C for 4-6h, can guarantee the final material to have a transmittance of ≤ 88-90% through high initial transmittance, and can avoid moisture interference in subsequent covalent bond connection reaction by controlling moisture and removing residues to prevent the material from having haze and transmittance decrease due to moisture. At the same time, it can also improve the compatibility of resin and flame-retardant antistatic agent, reduce performance defects, lay a foundation for stable core performance such as optical and mechanical performance, and help produce qualified optical PC flame-retardant weather-resistant antistatic materials.

[0024] In S2, the reaction of PC macromolecules and flame-retardant antistatic agent is completed by a twin-screw extruder, and the equipment parameters need to be strictly set: the feeding section temperature is controlled at 220-240°C, the melting section temperature is set at 260-280°C, the homogenization section temperature is maintained at 250-270°C, the die temperature is adjusted to 240-260°C, and the screw speed is controlled at 250-350r / min; this parameter combination can ensure that PC and flame-retardant antistatic agent are fully melted and mixed, promote the formation of stable covalent bonds between the functional groups of the two, and provide process protection for the subsequent standard transmittance and flame-retardant performance of the material.

[0025] In S2, the twin-screw extruder parameters are set as follows: the feeding section temperature is ≤ 220-240°C, the melting section temperature is ≤ 260-280°C, the homogenization section temperature is ≤ 250-270°C, the die temperature is ≤ 240-260°C, and the screw speed is ≤ 250-350r / min; this can ensure that PC and flame-retardant antistatic agent are fully melted and mixed, promote the formation of stable covalent bonds between the functional groups of the two, which can avoid performance defects caused by uneven mixing or insufficient reaction, provide key process protection for the subsequent ≤ 88-90% transmittance and UL94-V0 grade flame retardancy of the material, and at the same time, ensure production stability, and help efficient industrialization of qualified optical PC flame-retardant weather-resistant antistatic materials.

[0026] In the optical PC flame-retardant weather-resistant antistatic material, the weather resistance needs to be verified by specific tests: QUV aging test is used with UVB-313 lamp as the irradiation source, the irradiation time is set at 2000h, the condensation time is set at 168h, and after the test, the material needs to meet two core indicators: yellow index (YI) ≤ 2.0 to ensure that the optical transparency is not significantly affected; at the same time, the surface resistance change amplitude is ≤ 2 orders of magnitude to maintain stable antistatic performance. This weather resistance standard can ensure that the core performance of the material does not degrade when used in long-term outdoor or complex environments, and meets the needs of industrialization for durability.

[0027] The weather resistance is verified by less than or equal to QUV less than or equal to aging test (UVB-313 less than or equal to lamp tube, irradiation less than or equal to 2000h, condensation less than or equal to 168h), that is, the optical transparency is ensured not to decrease significantly by less than or equal to yellowing index of 2.0, and the optical performance of the material core is maintained; and the anti-static performance is ensured to be stable by less than or equal to change of surface resistance of 2 orders of magnitude. This can prevent the core performance of the material from degrading when used in long-term outdoor or complex environments, avoid losing the light transmission and anti-static functions due to environmental impact, meet the demand of the electronic and building material fields for material durability, and provide key environmental adaptability support for industrial application thereof.

[0028] The heat resistance of the material needs to meet double requirements: one is that the heat distortion temperature is greater than or equal to 150℃ under the condition of 0.45MPa pressure, so as to ensure that the material is not easy to deform in a medium-high temperature environment; and the other is that the impact strength retention rate of the material is greater than or equal to 90% and the light transmittance retention rate is greater than or equal to 95% after 1000h of hot air aging at 150℃, so as to effectively resist the damage of long-term high temperature to the mechanical and optical performances; and the heat resistance performance can be adapted to various high-temperature application scenarios, and further supports the industrial practical value of the material.

[0029] In addition to the halogen-free flame retardant perfluorobutyl sulfonate, polyvinyl alcohol (PVA) and bisphenol A compound, the auxiliary synergistic material in S1 also needs to add 0.5-1 parts of a silane coupling agent (such as model KH-560) in mass fraction. The silane coupling agent needs to be put into the reaction system together with the perfluorobutyl sulfonate and PVA at the initial stage of the cross-linking reaction, and its core role is to optimize the interfacial bonding state of the flame-retardant anti-static agent and the PC unit prepared subsequently, significantly improve the compatibility of the two, and provide support for the stable connection of the covalent bond and the high light transmittance and low outgassing performance of the material.

[0030] The addition of less than or equal to 0.5-1 parts of a silane coupling agent (such as less than or equal to KH-560) in the auxiliary synergistic material in S1 and the simultaneous addition of the perfluorobutyl sulfonate and PVA at the initial stage of the cross-linking reaction can optimize the interfacial bonding state of the flame-retardant anti-static agent and the PC unit, and significantly improve the compatibility of the two. This not only lays a foundation for the stable formation of a covalent bond between the two, but also helps the material to maintain high light transmittance (up to less than or equal to 88-90%) and low outgassing (no migration and outgassing on the surface) performance, avoids the decrease of light transmittance or outgassing problems caused by poor compatibility, further ensures that the core performance of the material meets the standards, and provides key support for the industrial application thereof.

[0031] The impact resistance of the material needs to strictly meet a specific test standard: according to GB / T1843-2021 standard detection, the Izod notched impact strength is greater than or equal to 8kJ / m² at 23°C normal temperature environment; after-30°C low temperature test (using notched type A), the impact strength still needs to be greater than or equal to 6kJ / m², and the material has no obvious cracking phenomenon. The anti-impact performance benefits from the enhanced linkage formed by the benzene ring in the PC molecular chain and the hydroxyl group in PVA, which can ensure that the material has stable mechanical performance in normal and low temperature scenes, and meets the application requirements of multi-environment industrialization.

[0032] According to the impact resistance requirement of less than or equal to GB / T1843-2021 standard, the Izod notched impact strength is greater than or equal to 8kJ / m² at 23°C normal temperature, and greater than or equal to 6kJ / m² at-30°C low temperature (notched less than or equal to A), and less than or equal to without cracking, which can accurately verify the mechanical stability of the material; and relying on the enhanced linkage of less than or equal to PC less than or equal to benzene ring and less than or equal to PVA less than or equal to hydroxyl group, it can ensure that the material has stable performance in normal and low temperature scenes, and avoid mechanical failure caused by temperature fluctuation. This not only adapts to the multi-environment industrialization application of electronic, building materials and other industries, but also ensures the anti-impact ability of the material in use, reduces the cracking loss, prolongs the service life, and further strengthens its industrialization practical value.

[0033] Preparation example one of optical less than or equal to PC less than or equal to flame-retardant weather-resistant anti-static material I. Raw material preparation S1: Auxiliary synergistic material: halogen-free flame retardant perfluorobutyl sulfonate less than or equal to 40g, polyvinyl alcohol (PVA, degree of polymerization less than or equal to 1700) 35g, bisphenol less than or equal to A less than or equal to type polycarbonate oligomer (number average molecular weight less than or equal to 750) 20g, silane coupling agent less than or equal to KH-560 5g; the total mass of auxiliary synergistic material is less than or equal to 100g, and the content of bisphenol less than or equal to A less than or equal to type polycarbonate oligomer is less than or equal to 20% (complying with the requirement of less than or equal to 15%-25%), and the total amount of flame-retardant anti-static agent is less than or equal to 3 parts (controlled in the range of less than or equal to 1-5 parts) finally. S2: PC unit: optical grade transparent PC resin (transmittance less than or equal to 93% when the thickness is less than or equal to 3mm, moisture content less than or equal to 0.015%) 1000g, which is vacuum dried at less than or equal to 125°C for less than or equal to 5h (drying temperature less than or equal to 120-130°C, time less than or equal to 4-6h) before use. II. Preparation steps S1: Synthesis of flame-retardant anti-static agent; Into less than or equal to 500 mL less than or equal to reactor, add less than or equal to 200 mL less than or equal to deionized water (reaction medium), and sequentially add perfluorobutyl sulfonate, PVA, silane coupling agent less than or equal to KH-560, and after stirring and dissolving, add bisphenol less than or equal to A less than or equal to polycarbonate oligomer; Set the reaction temperature to less than or equal to 80°C (70-90°C), the stirring rate to less than or equal to 250 r / min (200-300 r / min), and protect by nitrogen gas for less than or equal to 4 h (3-5 h); After the reaction is completed, the product is sent to a spray dryer, the inlet air temperature is set to less than or equal to 190°C (180-200°C), the outlet air temperature is set to less than or equal to 85°C (80-90°C), and after drying, white flame-retardant antistatic agent powder with a particle size of less than or equal to 7 μm (5-10 μm) is collected. S2: Covalently link the flame-retardant antistatic agent to less than or equal to PC; According to a mass ratio of less than or equal to 4 less than or equal to parts (3-5 less than or equal to parts) of the flame-retardant antistatic agent: 100 less than or equal to parts of the PC resin, the dried PC resin and the flame-retardant antistatic agent are put into a hopper of a twin-screw extruder. Set the extruder parameters: the feeding section to less than or equal to 230°C (220-240°C), the melting section to less than or equal to 270°C (260-280°C), the homogenizing section to less than or equal to 260°C (250-270°C), and the die head to less than or equal to 250°C (240-260°C), the screw rotation speed to less than or equal to 300 r / min (250-350 r / min), and extrude and granulate to obtain mixed particles. S3: Form the target material; Put the mixed particles obtained in S2 into an injection molding machine, set the injection molding temperature to less than or equal to 250-260°C, and the mold temperature to less than or equal to 80°C, injection mold into a standard sample with a thickness of less than or equal to 3 mm, and obtain the optical PC flame-retardant weather-resistant antistatic material.

[0034] III. Performance test results Optical performance: the sample transmittance is less than or equal to 89% (complying with less than or equal to 88% to 90% requirements); Flame-retardant performance: according to the UL94 standard test, V0 level is achieved; Antistatic performance: the surface resistance is less than or equal to 6.2×10 9 Ω (1.0×10 8 Ω ~ 1.0×10¹¹ Ω), after being placed at a constant temperature of less than or equal to 60°C for less than or equal to 30 d, the surface is free of migration and precipitation of the flame-retardant antistatic agent; Weather resistance: less than or equal to QUV less than or equal to aging test (UVB-313 less than or equal to lamp, irradiation less than or equal to 2000h, condensation less than or equal to 168h), yellowing index (YI) 1.8 (less than or equal to 2.0), surface resistance change less than or equal to 1.2 (less than or equal to 2 orders of magnitude); Heat resistance: heat distortion temperature less than or equal to 155℃ (≥150℃) under a pressure of 0.45MPa; after less than or equal to 1000h of hot air aging at less than or equal to 150℃, impact strength retention rate less than or equal to 92% (≥90%), light transmittance retention rate less than or equal to 96% (≥95%); Impact resistance: according to less than or equal to GB / T less than or equal to 1843-2021 test, 23℃ Izod notched impact strength less than or equal to 8.5kJ / m² (≥8kJ / m²); low temperature impact strength less than or equal to 6.5kJ / m² (≥6kJ / m²) at -30℃, and the sample has no obvious cracking.

[0035] Preparation example two of optical less than or equal to PC less than or equal to flame-retardant weather-resistant antistatic material I. Raw material preparation S1: auxiliary synergistic material: halogen-free flame retardant perfluorobutyl sulfonate less than or equal to 35g, polyvinyl alcohol (PVA, degree of polymerization less than or equal to 2000) 40g, bisphenol less than or equal to A less than or equal to type polycarbonate oligomer (number average molecular weight less than or equal to 600) 18g, silane coupling agent less than or equal to KH-550 less than or equal to 7g; the total mass of the auxiliary synergistic material is less than or equal to 100g, wherein the bisphenol less than or equal to A less than or equal to type polycarbonate oligomer accounts for less than or equal to 18% (in line with the requirements of less than or equal to 15%-25%), and the total amount of the flame-retardant antistatic agent is less than or equal to 4 parts (controlled within the range of less than or equal to 1-5 parts) finally obtained. S2: PC unit: optical grade transparent less than or equal to PC less than or equal to resin (light transmittance less than or equal to 94% when the thickness is less than or equal to 3mm, moisture content less than or equal to 0.018%) 1000g, which is vacuum dried less than or equal to 6h at less than or equal to 120℃ before use (drying temperature less than or equal to 120-130℃, time less than or equal to 4-6h). II. Preparation steps S1: synthesis of flame-retardant antistatic agent; Into a less than or equal to 1000mL less than or equal to reaction kettle, add less than or equal to 300mL less than or equal to deionized water (reaction medium), first put in perfluorobutyl sulfonate and less than or equal to PVA, stir until completely dissolved, then add silane coupling agent less than or equal to KH-550 less than or equal to and bisphenol less than or equal to A less than or equal to type polycarbonate oligomer; The reaction temperature is set to be less than or equal to 75°C (70-90°C), the stirring rate is less than or equal to 220 r / min (200-300 r / min), the whole process is protected by inert gas (argon), and the reaction lasts for less than or equal to 5 h (3-5 h); After the reaction is completed, the product is introduced into a spray dryer, the inlet air temperature is set to be less than or equal to 185°C (180-200°C), the outlet air temperature is set to be less than or equal to 82°C (80-90°C), and after drying, a light yellow flame-retardant antistatic agent powder with a particle size of less than or equal to 9 μm (5-10 μm) is collected. S2: the flame-retardant antistatic agent is covalently connected to PC; The flame-retardant antistatic agent and PC resin are mixed in a mass ratio of less than or equal to 5 parts (3-5 parts) to 100 parts, and the dried PC resin is mixed with the flame-retardant antistatic agent uniformly, and then put into the hopper of a double-screw extruder; The extruder parameters are set as follows: the feeding section is less than or equal to 225°C (220-240°C), the melting section is less than or equal to 265°C (260-280°C), the homogenizing section is less than or equal to 255°C (250-270°C), the die head is less than or equal to 245°C (240-260°C), the screw rotation speed is less than or equal to 280 r / min (250-350 r / min), and the uniformly mixed particles are obtained by extrusion granulation. S3: the target material is prepared by molding; The mixed particles obtained in S2 are used in an extrusion molding process, the temperature of the extruder body is set to be less than or equal to 255-265°C, the temperature of the die head is set to be less than or equal to 250°C, the pulling rate is less than or equal to 2 m / min, and a plate sample with a thickness of less than or equal to 5 mm is prepared, thereby obtaining an optical PC flame-retardant weather-resistant antistatic material. III. Performance test results Optical performance: the light transmittance of a 5 mm thick sample is less than or equal to 88% (complying with the requirement of less than or equal to 88%-90%); Flame-retardant performance: according to the UL94 standard test, the vertical burning reaches a V0 level (extinguishing time ≤10 s); Antistatic performance: the surface resistance is less than or equal to 8.5×10 8 Ω (1.0×10 8 Ω ~ 1.0×10¹¹ Ω), after being placed at a constant temperature of less than or equal to 70°C for less than or equal to 45 d, no precipitates are observed on the surface, and no migration traces are observed under electron microscopy; Weather resistance: less than or equal to QUV less than or equal to weathering test (UVB-313 less than or equal to lamp, irradiation less than or equal to 2000h, condensation less than or equal to 168h), yellow index (YI) 1.5 (≤2.0), surface resistance change less than or equal to 0.8 (≤2) orders of magnitude; heat resistance: heat distortion temperature less than or equal to 152℃ (≥150℃) under 0.45MPa pressure; after less than or equal to 1000h less than or equal to hot air aging at 150℃, impact strength retention rate less than or equal to 91% (≥90%), light transmittance retention rate less than or equal to 95.5% (≥95%); impact resistance: according to less than or equal to GB / T less than or equal to 1843-2021 less than or equal to test, 23℃ Izod notched impact strength less than or equal to 8.2kJ / m² (≥8kJ / m²); low temperature impact strength at -30℃ less than or equal to 6.3kJ / m² (≥6kJ / m²), the sample fracture surface is smooth without cracking.

[0036] It should be noted that the relational terms herein such as first and second and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any such actual relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus.

[0037] Although embodiments of the present application have been shown and described, it is to be understood that various modifications, substitutions, replacements and changes can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A method for preparing an optical PC flame-retardant, weather-resistant and antistatic material, characterized by: The specific steps of this preparation method are as follows: S1: Select materials to synthesize flame retardant and antistatic agent: A flame retardant antistatic agent containing a halogen-free transparent element is prepared by selecting a halogen-free flame retardant perfluorobutyl sulfonate, polyvinyl alcohol, and a bisphenol A compound as auxiliary synergists through a cross-linking synthesis reaction; the flame retardant antistatic agent has dual functional groups of sulfonic acid and hydroxyl groups, and the total amount of the flame retardant antistatic agent prepared is controlled to be 1-5 parts; S2: Flame retardant doped PC covalently linked: The flame retardant and antistatic agent prepared in S1 is added to the polycarbonate unit at a mass ratio of 3-5 parts. Through the reaction, the PC macromolecules are connected by covalent bonds with the sulfonic acid groups and hydroxyl groups in the flame retardant and antistatic agent, achieving compatible and uniform arrangement of the sulfonic acid groups and hydroxyl groups in the PC molecular chain. During the connection process, the in-situ unchanged characteristics of the "carbonate" core group in the PC molecular chain are stabilized, reducing the light scattering of the molecular chain; S3: Mixture molding target PC material: The mixture obtained in S2 is molded to produce an optical PC flame retardant, weather resistant and antistatic material. The material must meet the following requirements: a light transmittance of 88% to 90%, a flame retardant performance that meets UL94-V0 level, and a surface resistance of 1.0×10 8 Ω∼1.0×10¹¹Ω, and there is no migration and precipitation of flame retardant and antistatic agents on the surface of the material; at the same time, the benzene ring in the PC molecular chain and the hydroxyl structure of PVA form a reinforced link to ensure that there is no cracking inside the material, giving the material excellent impact resistance, weather resistance and heat resistance, meeting the needs of industrial applications.

2. The method for preparing an optical PC flame-retardant, weather-resistant and antistatic material according to claim 1, characterized in that: The bisphenol A compound in S1 is specifically a bisphenol A polycarbonate oligomer, the number average molecular weight of which is strictly controlled within the range of 500-1000, and the mass proportion of the oligomer in the auxiliary synergistic material composed of the halogen-free flame retardant perfluorobutyl sulfonate, polyvinyl alcohol and itself is maintained at 15%-25%. This parameter setting can adapt to the needs of the cross-linking synthesis reaction, help generate a flame retardant antistatic agent containing sulfonic acid groups and hydroxyl groups, and at the same time provide a guarantee for the subsequent compatible combination with the PC unit and maintain the high transparency core performance of the material.

3. The method for preparing an optical PC flame-retardant, weather-resistant and antistatic material according to claim 1, characterized in that: The cross-linking synthesis reaction in S1 uses deionized water as the reaction medium, and the key conditions are strictly controlled: the reaction temperature is controlled at 70-90°C, the stirring rate is set to 200-300r / min, and the reaction is continued for 3-5 hours to ensure sufficient reaction. After the reaction is completed, the product is treated by a spray drying process, wherein the inlet air temperature is controlled at 180-200°C and the outlet air temperature is 80-90°C. Finally, a flame retardant antistatic agent powder with a uniform particle size in the range of 5-10μm is obtained, laying the foundation for subsequent compatible combination with PC units.

4. The method for preparing an optical PC flame-retardant, weather-resistant and antistatic material according to claim 1, characterized in that: The PC unit used in S2 is an optical-grade transparent PC resin, which must meet key indicators: a light transmittance greater than or equal to 92% at a thickness of 3 mm, and a moisture content less than or equal to 0.02% in the resin to prevent moisture from affecting subsequent reactions and the optical properties of the material. To further ensure compatibility and product quality, the optical-grade transparent PC resin must first be vacuum-dried at 120-130°C before being mixed with the flame retardant and antistatic agent prepared in S1, and the drying time must be controlled at 4-6 hours.

5. The method for preparing an optical PC flame-retardant, weather-resistant and antistatic material according to claim 1, characterized in that: The reaction between the PC macromolecules and the flame retardant and antistatic agent in S2 is completed using a twin-screw extruder, and the equipment parameters must be strictly set: the feeding section temperature is controlled at 220-240°C, the melting section temperature is set at 260-280°C, the homogenization section temperature is maintained at 250-270°C, the head temperature is adjusted to 240-260°C, and the screw speed is controlled at 250-350r / min. This parameter combination can ensure that the PC and the flame retardant and antistatic agent are fully melt-mixed, promote the formation of stable covalent bonds between the functional groups of the two, and provide process guarantees for the subsequent compliance of the material with the standard light transmittance and flame retardancy properties.

6. The method for preparing an optical PC flame-retardant, weather-resistant and antistatic material according to claim 1, characterized in that: The weather resistance of the optical PC flame-retardant, weather-resistant and antistatic material must be verified through specific tests: using the QUV aging test, with UVB-313 lamps as the irradiation source, and setting the irradiation time to 2000 hours and the condensation time to 168 hours. After the test, the material must meet two core indicators: the yellowing index is less than or equal to 2.0 to ensure that the optical transparency is not significantly affected; at the same time, the surface resistance change range is less than or equal to 2 orders of magnitude to maintain stable antistatic performance.

7. The method for preparing an optical PC flame-retardant, weather-resistant and antistatic material according to claim 1, characterized in that: The heat resistance of the material must meet dual requirements: first, under a pressure of 0.45MPa, the thermal deformation temperature is greater than or equal to 150°C, ensuring that the material is not easily deformed in medium and high temperature environments; second, after aging in hot air at 150°C for 1000 hours, the material's impact strength retention rate is greater than or equal to 90%, and the transmittance retention rate is greater than or equal to 95%, which can effectively resist the damage of long-term high temperature to mechanical and optical properties; this heat resistance performance can adapt to a variety of high-temperature application scenarios, further supporting the industrial practical value of the material.

8. The method for preparing an optical PC flame-retardant, weather-resistant and antistatic material according to claim 1, characterized in that: In addition to the halogen-free flame retardant perfluorobutane sulfonate, polyvinyl alcohol and bisphenol A compound, the auxiliary synergistic material in S1 also needs to add a silane coupling agent with a mass fraction of 0.5-1 parts. The silane coupling agent needs to be added to the reaction system together with perfluorobutane sulfonate and PVA at the initial stage of the cross-linking synthesis reaction. Its core function is to optimize the interfacial bonding state between the subsequently obtained flame retardant and antistatic agent and the PC unit.

9. The method for preparing an optical PC flame-retardant, weather-resistant and antistatic material according to claim 1, characterized in that: The impact resistance of the material must strictly comply with specific test standards: tested according to GB / T1843-2021 standard, at a normal temperature of 23°C, its cantilever beam notched impact strength is greater than or equal to 8kJ / m²; after testing at a low temperature of -30°C, the impact strength must still be greater than or equal to 6kJ / m², and the material must not show obvious cracking. This impact resistance is due to the enhanced link formed by the benzene ring in the PC molecular chain and the PVA hydroxyl group.

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