Weatherable flame-retardant polycarbonate / pbt composite and method of making same

Abstract

The application discloses weather-resistant flame-retardant polycarbonate / PBT composite material and a preparation method thereof, and belongs to the technical field of polycarbonate / PBT composite material preparation. The weather-resistant flame-retardant polycarbonate / PBT composite material is composed of the following components in parts by weight: 40-60 parts of polycarbonate, 48-62 parts of polybutylene terephthalate, 0.3-0.8 parts of a composite weather-resistant agent, 5-10 parts of a composite flame retardant, 0.8-1.2 parts of polytetrafluoroethylene, 0.4-0.9 parts of an antioxidant, 6-12 parts of a toughening agent, 0.1-0.4 parts of a lubricant and 0.2-0.5 parts of a dispersing agent. The polycarbonate / PBT composite material prepared according to the above material has excellent weather resistance and flame retardance.

Description

Technical Field

[0001] This invention belongs to the field of composite material preparation technology, specifically relating to weather-resistant and flame-retardant polycarbonate / PBT composite materials and their preparation methods. Background Technology

[0002] Polycarbonate (PC) and polybutylene terephthalate (PBT) composites are prepared through physical or chemical blending, combining the high toughness and heat resistance of PC with the chemical stability and processing performance of PBT. They are widely used in electronics, automotive, and other industries. However, pure PC / PBT composites suffer from insufficient weather resistance and flame retardancy. PC is susceptible to UV aging, leading to a decline in mechanical properties, while the crystalline characteristics of PBT make it prone to microcrack propagation in long-term humid and hot environments. Furthermore, PBT itself only achieves a UL94 HB flame retardancy rating, and although PC has some flame retardancy, it is prone to dripping during combustion. Blending the two further weakens the flame retardancy, making it difficult to meet the needs of outdoor equipment or high-safety-requirement scenarios.

[0003] Patent CN 121379095A discloses a polycarbonate / PBT / APT composite material and its preparation method. This composite material is prepared by mixing polycarbonate, PBT, a polysiloxane-polycarbonate random copolymer, attapulgite treated with PCA filler dispersant, and KT-22. The addition of polysiloxane-polycarbonate, KT-22, and APT effectively improves the interfacial compatibility and mechanical properties of the material, resulting in a higher cost-performance ratio. It also enhances the mechanical properties and processing fluidity of the composite material, meeting the needs of high-end applications and showing broader application prospects. Although the composite material prepared by the above method exhibits excellent performance in terms of interfacial compatibility and mechanical properties, there is still room for improvement in flame retardancy and weather resistance. Currently, this composite material does not emphasize the addition of highly efficient flame-retardant components, making it difficult to effectively prevent flame spread and heat transfer when exposed to a fire source, resulting in poor flame retardant performance. Regarding weather resistance, since some components of the material are sensitive to environmental factors such as ultraviolet radiation, prolonged exposure to outdoor environments can cause the breakage of chemical bonds and changes in molecular structure within the material. This can lead to phenomena such as powdering and discoloration on the surface, as well as a gradual deterioration of internal properties, affecting its service life and performance stability. Therefore, by adding appropriate flame retardants and weather-resistant additives, the formulation of composite materials can be further optimized to improve their flame retardancy and weather resistance, meeting the requirements of more demanding scenarios. Summary of the Invention

[0004] The purpose of this invention is to provide a weather-resistant and flame-retardant polycarbonate / PBT composite material and its preparation method, in order to solve the technical problem of poor weather resistance and flame retardancy of composite materials in the prior art.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] This invention provides a weather-resistant and flame-retardant polycarbonate / PBT composite material, which is composed of the following components in parts by weight: 40-60 parts polycarbonate, 48-62 parts polybutylene terephthalate, 0.3-0.8 parts composite weathering agent, 5-10 parts composite flame retardant, 0.8-1.2 parts polytetrafluoroethylene, 0.4-0.9 parts antioxidant, 6-12 parts toughening agent, 0.1-0.4 parts lubricant, and 0.2-0.5 parts dispersant.

[0007] Preferably, the preparation method of the composite weather-resistant agent includes the following steps:

[0008] Q1: Under nitrogen atmosphere, di(trichloromethyl) carbonate was added to a container containing dichloromethane. After stirring and mixing, the mixture was cooled. Then, dichloromethane containing pentafluoride (4-aminophenyl)sulfur and triethylamine was added dropwise. After heating and reacting, the mixture was cooled again. Subsequently, dichloromethane containing 1-tert-butoxycarbonyl-4-aminomethylpiperidine and triethylamine was added. After heating and reacting, the mixture was concentrated under reduced pressure and purified to obtain organic compound 1.

[0009] Q2: Organic compound 1 is added to a container containing a mixed solution of hydrochloric acid and methanol, hydrogenated at room temperature, and then concentrated under reduced pressure to obtain organic compound 2.

[0010] Q3: Add organic compound 2 to a container containing acetonitrile, stir, then add potassium carbonate and 1,1,1-trifluoro-3-iodopropane, heat and stir to react, then add distilled water, extract, dry, concentrate under reduced pressure, purify, and dry to obtain a composite weathering agent.

[0011] In the above process, the synthesis reaction formula of the composite weather-resistant agent is as follows:

[0012]

[0013] The mass spectrometry analysis results of organic compound 1 were: m / z: 459.16 (100.0%), 460.16 (21.4%), 461.16 (4.9%), 461.17 (2.5%); the mass spectrometry analysis results of organic compound 2 were: m / z: 359.11 (100.0%), 360.11 (16.0%), 361.10 (4.5%); the mass spectrometry analysis results of the composite weathering agent were: m / z: 455.13 (100.0%), 456.13 (18.4%), 457.12 (4.5%), 457.13 (1.9%), 456.12 (1.1%).

[0014] Preferably, in Q1, the ratio of di(trichloromethyl) carbonate, pentafluorinated (4-aminophenyl) sulfide, and 1-tert-butoxycarbonyl-4-aminomethylpiperidine is (0.85-0.97) g : (1.22-1.78) g : (1.96-2.14) g. The mixture is cooled to -78 to -80°C, then heated to 0-1°C and reacted for 1-2 hours. The mixture is then cooled to -78 to -80°C, then heated to 28-30°C and reacted for 30-45 minutes. The mixture is then concentrated under reduced pressure at 40-45°C, and purified using a mixture of petroleum ether and ethyl acetate with a volume ratio of 1-10:1 as the eluent.

[0015] Preferably, in Q2, the ratio of organic compound 1, hydrochloric acid and methanol is (0.72-0.83) g: (5-8) mL: (2-4) mL, the concentration of hydrochloric acid is 2 mol / L, and the hydrogenation reaction time is 10-12 h.

[0016] Preferably, in Q3, the ratio of organic compound 2, acetonitrile, potassium carbonate, and 1,1,1-trifluoro-3-iodopropane is (0.28-0.34) g : (8-12) mL : (0.31-0.38) g : (0.33-0.42) g. The mixture is heated to 58-64℃ and stirred for 14-16 h. It is then extracted with ethyl acetate, dried with anhydrous sodium sulfate, concentrated under reduced pressure at 40-42℃, and purified using a mixed solution of petroleum ether and ethyl acetate at a volume ratio of 5-10:1 as the eluent.

[0017] Preferably, the preparation method of the composite flame retardant includes the following steps:

[0018] S1: Cesium carbonate, cuprous chloride, and 5-bromo-2-pyridinecarboxaldehyde were added to a container containing N,N-dimethylformamide. After stirring at room temperature, N,N-dimethylformamide containing pyridine-2-methanethiol was added, and the mixture was heated to reflux. After the reaction was completed, the mixture was cooled, rotary evaporated, dissolved, washed, dried, and purified to obtain product a.

[0019] S2: Add product a and aminotriazinone hydrochloride to a container containing methanol, heat under reflux, cool, rotary evaporate, dissolve, and purify to obtain a composite flame retardant.

[0020] In the above process, the synthesis reaction formula of the composite flame retardant is as follows:

[0021]

[0022] The mass spectrometry analysis results of product a were: m / z: 230.05 (100.0%), 231.05 (14.5%), 232.05 (4.7%), 232.06 (1.0%); the mass spectrometry analysis results of the composite flame retardant were: m / z: 340.11 (100.0%), 341.11 (20.4%), 342.11 (5.3%), 342.12 (1.4%).

[0023] Preferably, in step S1, the ratio of cesium carbonate, cuprous chloride, 5-bromo-2-pyridinecarboxaldehyde, and pyridine-2-methanethiol is (0.588-0.625) g : (0.344-0.362) g : (0.532-0.571) g : (0.342-0.386) g. The mixture is stirred at room temperature for 10-15 min, heated to reflux at 60-70°C for 10-12 h, cooled to 28-30°C, dissolved in dichloromethane, washed with saturated sodium chloride, dried with anhydrous sodium sulfate, and purified using a mixture of petroleum ether and ethyl acetate in a volume ratio of 3-5:1 as the eluent.

[0024] Preferably, in step S2, the ratio of product a, aminotriazinone hydrochloride, and methanol is (0.914-0.995) g : (0.674-0.698) g : (25-35) mL. The reaction is heated to reflux at 60-64°C for 10-12 h, then cooled to 28-30°C, dissolved in dichloromethane, and purified using a mixture of petroleum ether and ethyl acetate at a volume ratio of 2-5:1 as the eluent.

[0025] Preferably, the method for preparing the weather-resistant and flame-retardant polycarbonate / PBT composite material includes the following steps:

[0026] Step 1: Add the dried polycarbonate and polybutylene terephthalate to the mixer, stir and mix, then add the composite weathering agent, antioxidant, lubricant and dispersant in sequence, continue stirring, then add the composite flame retardant and toughening agent, heat and stir to mix, and obtain the dry mixture.

[0027] Step 2: Add the dry mixture to the main feed hopper of the twin-screw extruder, then add polytetrafluoroethylene through the side feed hopper, heat and extrude, granulate, dry, screen, and package to obtain a weather-resistant and flame-retardant polycarbonate / PBT composite material.

[0028] Preferably, in step one, the mixture is heated to 60-80℃ and stirred for 3-5 minutes; in step two, the temperatures during the heating and extrusion process are set as follows: feeding section temperature 220-240℃, melting section temperature 240-260℃, mixing section temperature 250-270℃, metering section temperature 240-260℃, die head temperature 250-265℃, screw speed 300-600 rpm, drying temperature 100-110℃, and time 3-4 hours.

[0029] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0030] 1. The present invention applies the prepared composite weathering agent and composite flame retardant to composite materials, which can effectively improve the weather resistance, hydrophobic and oleophobic properties and flame retardant properties of composite materials.

[0031] 2. The composite weathering agent obtained in this invention can be applied to composite materials to effectively improve their weather resistance and hydrophobic and oleophobic properties. The sulfur pentafluoride groups contained in the composite weathering agent can efficiently absorb and quench ultraviolet rays, inhibiting the yellowing and molecular chain breakage of polycarbonate and PBT under photothermal aging conditions. The fluorinated propyl segments contained therein can reduce the surface energy of the material, giving the composite material excellent hydrophobic and oleophobic properties and self-cleaning ability, delaying the erosion and hydrolysis of the ester structure by water and corrosive media. In addition, the weathering agent forms a flexible connection through piperidine bridges, which is uniformly dispersed in the polymer matrix and has good compatibility, avoiding the migration and precipitation of additives. Thus, the composite material can still maintain excellent performance under long-term outdoor exposure and extend the service life of the product.

[0032] 3. The present invention applies the prepared composite flame retardant to composite materials, giving them the advantages of smoke suppression and synergistic flame retardancy. It can also significantly improve interfacial compatibility. The pyridine ring and triazine ketone structure contained in the composite flame retardant decompose at high temperature to release non-flammable gases, dilute the concentration of combustible volatiles, and promote the heat-carrying effect when the melt drips. In addition, the polar groups contained in the composite flame retardant form hydrogen bonds with polycarbonate / PBT composite materials, improving the compatibility between the two and preventing the migration of the composite flame retardant. Detailed Implementation

[0033] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] Example 1: This example discloses a method for preparing a composite weather-resistant agent, including the following steps:

[0035] Q1: Under nitrogen atmosphere, 0.91 g of di(trichloromethyl) carbonate was added to a container containing 15 mL of dichloromethane. After stirring and mixing, the mixture was cooled to -78 °C. Then, 15 mL of dichloromethane containing 1.45 g of pentafluoride (4-aminophenyl)sulfur and 1.04 g of triethylamine was added dropwise. The mixture was heated to 0 °C and reacted for 1 h. The mixture was then cooled to -78 °C. Subsequently, 15 mL of dichloromethane containing 2.02 g of 1-tert-butoxycarbonyl-4-aminomethylpiperidine and 1.04 g of triethylamine was added. The mixture was heated to 28 °C and reacted for 30 min. The mixture was then concentrated under reduced pressure at 40 °C. The mixture was purified using a 6:1 (v / v) mixture of petroleum ether and ethyl acetate as the eluent to obtain organic compound 1.

[0036] Q2: Add 0.78g of organic compound 1 to a container containing 6.5mL of a mixed solution of 2mol / L hydrochloric acid and 3mL of methanol. After hydrogenation at room temperature for 12h, concentrate under reduced pressure to obtain organic compound 2.

[0037] Q3: Add 0.31g of organic compound 2 to a container containing 10mL of acetonitrile, stir, then add 0.35g of potassium carbonate and 0.36g of 1,1,1-trifluoro-3-iodopropane. Heat to 60℃ and stir for 16h. Add distilled water, extract with ethyl acetate, dry with anhydrous sodium sulfate, concentrate under reduced pressure at 40℃, purify with a 7:1 (v / v) mixture of petroleum ether and ethyl acetate as the eluent, and dry to obtain the composite weathering agent.

[0038] This embodiment discloses a method for preparing a composite flame retardant, including the following steps:

[0039] S1: 0.601 g of cesium carbonate, 0.353 g of cuprous chloride, and 0.552 g of 5-bromo-2-pyridinecarboxaldehyde were added to a container containing 30 mL of N,N-dimethylformamide. After stirring at room temperature for 15 min, 10 mL of N,N-dimethylformamide containing 0.363 g of pyridine-2-methanethiol was added. The mixture was heated to reflux at 65 °C for 12 h. After the reaction was completed, the temperature was lowered to 28 °C, and the mixture was rotary evaporated. The product was dissolved in dichloromethane, washed with saturated sodium chloride, dried with anhydrous sodium sulfate, and purified using a mixture of petroleum ether and ethyl acetate in a volume ratio of 4:1 as the eluent to obtain product a.

[0040] S2: Add 0.955g of product a and 0.682g of aminotriazinone hydrochloride to a container containing 30mL of methanol, heat and reflux at 62℃ for 12h, then cool to 28℃, rotary evaporate, dissolve in dichloromethane, and purify using a mixed solution of petroleum ether and ethyl acetate in a volume ratio of 3:1 as the eluent to obtain the composite flame retardant.

[0041] This embodiment discloses a weather-resistant and flame-retardant polycarbonate / PBT composite material, which is composed of the following components by weight: 50 parts polycarbonate, 55 parts polybutylene terephthalate, 0.5 parts composite weathering agent, 7.5 parts composite flame retardant, 1 part polytetrafluoroethylene, 0.6 parts antioxidant 1010, 9 parts ethylene-butyl acrylate-glycidyl methacrylate copolymer, 0.25 parts pentaerythritol stearate and 0.35 parts dispersant QC100.

[0042] This embodiment discloses a method for preparing a weather-resistant and flame-retardant polycarbonate / PBT composite material, including the following steps:

[0043] Step 1: Add the dried polycarbonate and polybutylene terephthalate to a mixer and stir to mix. Then, add the composite weathering agent, antioxidant 1010, pentaerythritol stearate and dispersant QC100 in sequence and continue stirring. Then, add the composite flame retardant and ethylene-butyl acrylate-glycidyl methacrylate copolymer. Heat to 70°C and stir to mix for 5 minutes to obtain a dry mixture.

[0044] Step 2: Add the dry mixture to the main feed hopper of the twin-screw extruder, then add polytetrafluoroethylene through the side feed hopper. Heat and extrude the mixture. The temperature settings during the process are as follows: feeding section temperature 230℃, melting section temperature 250℃, mixing section temperature 260℃, metering section temperature 250℃, die head temperature 255℃, screw speed 500rpm, granulation, drying at 100℃ for 4 hours, screening, and packaging to obtain weather-resistant and flame-retardant polycarbonate / PBT composite material.

[0045] Example 2: This example discloses a method for preparing a composite weather-resistant agent, including the following steps:

[0046] Q1: Under nitrogen atmosphere, 0.85 g of di(trichloromethyl) carbonate was added to a container containing 15 mL of dichloromethane. After stirring and mixing, the mixture was cooled to -78 °C. Then, 15 mL of dichloromethane containing 1.22 g of pentafluoride (4-aminophenyl)sulfur and 1.04 g of triethylamine was added dropwise. The mixture was heated to 0 °C and reacted for 1 h. The mixture was then cooled to -78 °C. Subsequently, 15 mL of dichloromethane containing 1.96 g of 1-tert-butoxycarbonyl-4-aminomethylpiperidine and 1.04 g of triethylamine was added. The mixture was heated to 28 °C and reacted for 30 min. The mixture was then concentrated under reduced pressure at 40 °C. The mixture was purified using a 6:1 (v / v) mixture of petroleum ether and ethyl acetate as the eluent to obtain organic compound 1.

[0047] Q2: Add 0.72g of organic compound 1 to a container containing 5mL of a mixed solution of 2mol / L hydrochloric acid and 2mL of methanol. After hydrogenation at room temperature for 12h, concentrate under reduced pressure to obtain organic compound 2.

[0048] Q3: Add 0.28g of organic compound 2 to a container containing 12mL of acetonitrile, stir, then add 0.31g of potassium carbonate and 0.33g of 1,1,1-trifluoro-3-iodopropane. Heat to 60℃ and stir for 16h. Add distilled water, extract with ethyl acetate, dry with anhydrous sodium sulfate, concentrate under reduced pressure at 40℃, purify with a 7:1 (v / v) mixture of petroleum ether and ethyl acetate as the eluent, and dry to obtain the composite weathering agent.

[0049] This embodiment discloses a method for preparing a composite flame retardant, including the following steps:

[0050] S1: 0.588 g of cesium carbonate, 0.344 g of cuprous chloride, and 0.532 g of 5-bromo-2-pyridinecarboxaldehyde were added to a container containing 30 mL of N,N-dimethylformamide. After stirring at room temperature for 15 min, 10 mL of N,N-dimethylformamide containing 0.342 g of pyridine-2-methanethiol was added. The mixture was heated to reflux at 65 °C for 12 h. After the reaction was completed, the temperature was lowered to 28 °C, and the mixture was rotary evaporated. The product was dissolved in dichloromethane, washed with saturated sodium chloride, dried with anhydrous sodium sulfate, and purified using a mixture of petroleum ether and ethyl acetate in a volume ratio of 4:1 as the eluent to obtain product a.

[0051] S2: Add 0.914 g of product a and 0.674 g of aminotriazinone hydrochloride to a container containing 25 mL of methanol, heat and reflux at 62 °C for 12 h, then cool to 28 °C, rotary evaporate, dissolve in dichloromethane, and purify using a mixed solution of petroleum ether and ethyl acetate in a volume ratio of 3:1 as the eluent to obtain the composite flame retardant.

[0052] This embodiment discloses a weather-resistant and flame-retardant polycarbonate / PBT composite material, which is composed of the following components by weight: 40 parts polycarbonate, 48 parts polybutylene terephthalate, 0.8 parts composite weathering agent, 10 parts composite flame retardant, 0.8 parts polytetrafluoroethylene, 0.4 parts antioxidant 168, 12 parts methyl methacrylate-butadiene-styrene copolymer, 0.4 parts silicone oil, and 0.5 parts dispersant AS-220.

[0053] This embodiment discloses a method for preparing a weather-resistant and flame-retardant polycarbonate / PBT composite material, including the following steps:

[0054] Step 1: Add the dried polycarbonate and polybutylene terephthalate to the mixer and stir to mix. Then add the composite weathering agent, antioxidant 168, silicone oil and dispersant AS-220 in sequence and continue stirring. Then add the composite flame retardant and methyl methacrylate-butadiene-styrene copolymer. Heat to 70°C and stir to mix for 5 minutes to obtain the dry mixture.

[0055] Step 2: Add the dry mixture to the main feed hopper of the twin-screw extruder, then add polytetrafluoroethylene through the side feed hopper. Heat and extrude the mixture. The temperature settings during the process are as follows: feeding section temperature 230℃, melting section temperature 250℃, mixing section temperature 260℃, metering section temperature 250℃, die head temperature 255℃, screw speed 500rpm, granulation, drying at 100℃ for 4 hours, screening, and packaging to obtain weather-resistant and flame-retardant polycarbonate / PBT composite material.

[0056] Example 3: This example discloses a method for preparing a composite weather-resistant agent, including the following steps:

[0057] Q1: Under nitrogen atmosphere, 0.97 g of di(trichloromethyl) carbonate was added to a container containing 15 mL of dichloromethane. After stirring and mixing, the mixture was cooled to -78 °C. Then, 15 mL of dichloromethane containing 1.78 g of pentafluoride (4-aminophenyl) sulfide and 1.04 g of triethylamine was added dropwise. The mixture was heated to 0 °C and reacted for 1 h. The mixture was then cooled to -78 °C. Subsequently, 15 mL of dichloromethane containing 2.14 g of 1-tert-butoxycarbonyl-4-aminomethylpiperidine and 1.04 g of triethylamine was added. The mixture was heated to 28 °C and reacted for 30 min. The mixture was then concentrated under reduced pressure at 40 °C. The mixture was purified using a 6:1 (v / v) mixture of petroleum ether and ethyl acetate as the eluent to obtain organic compound 1.

[0058] Q2: Add 0.83g of organic compound 1 to a container containing 8mL of a mixed solution of 2mol / L hydrochloric acid and 4mL of methanol. After hydrogenation at room temperature for 12h, concentrate under reduced pressure to obtain organic compound 2.

[0059] Q3: Add 0.34g of organic compound 2 to a container containing 8mL of acetonitrile, stir, then add 0.38g of potassium carbonate and 0.42g of 1,1,1-trifluoro-3-iodopropane. Heat to 60℃ and stir for 16h. Add distilled water, extract with ethyl acetate, dry with anhydrous sodium sulfate, concentrate under reduced pressure at 40℃, purify with a 7:1 volume ratio of petroleum ether and ethyl acetate as eluent, and dry to obtain the composite weathering agent.

[0060] This embodiment discloses a method for preparing a composite flame retardant, including the following steps:

[0061] S1: 0.625 g cesium carbonate, 0.362 g cuprous chloride, and 0.571 g 5-bromo-2-pyridinecarboxaldehyde were added to a container containing 30 mL N,N-dimethylformamide. After stirring at room temperature for 15 min, 10 mL of N,N-dimethylformamide containing 0.386 g pyridine-2-methanethiol was added. The mixture was heated to reflux at 65 °C for 12 h. After the reaction was completed, the temperature was lowered to 28 °C, and the mixture was rotary evaporated. The product was dissolved in dichloromethane, washed with saturated sodium chloride, dried with anhydrous sodium sulfate, and purified using a mixed solution of petroleum ether and ethyl acetate in a volume ratio of 4:1 as the eluent to obtain product a.

[0062] S2: Add 0.995g of product a and 0.698g of aminotriazinone hydrochloride to a container containing 35mL of methanol, heat and reflux at 62℃ for 12h, cool to 28℃, rotary evaporate, dissolve in dichloromethane, and purify using a mixed solution of petroleum ether and ethyl acetate in a volume ratio of 3:1 as the eluent to obtain the composite flame retardant.

[0063] This embodiment discloses a weather-resistant and flame-retardant polycarbonate / PBT composite material, which is composed of the following components by weight: 60 parts polycarbonate, 62 parts polybutylene terephthalate, 0.3 parts composite weathering agent, 5 parts composite flame retardant, 1.2 parts polytetrafluoroethylene, 0.9 parts antioxidant 1076, 6 parts ethylene-octene copolymer grafted maleic anhydride, 0.1 parts silicone powder and 0.2 parts dispersant MG-555.

[0064] This embodiment discloses a method for preparing a weather-resistant and flame-retardant polycarbonate / PBT composite material, including the following steps:

[0065] Step 1: Add the dried polycarbonate and polybutylene terephthalate to the mixer and stir to mix. Then add the composite weathering agent, antioxidant 1076, silicone powder and dispersant MG-555 in sequence and continue stirring. Then add the composite flame retardant and ethylene-octene copolymer grafted maleic anhydride. Heat to 70°C and stir to mix for 5 minutes to obtain the dry mixture.

[0066] Step 2: Add the dry mixture to the main feed hopper of the twin-screw extruder, then add polytetrafluoroethylene through the side feed hopper. Heat and extrude the mixture. The temperature settings during the process are as follows: feeding section temperature 230℃, melting section temperature 250℃, mixing section temperature 260℃, metering section temperature 250℃, die head temperature 255℃, screw speed 500rpm, granulation, drying at 100℃ for 4 hours, screening, and packaging to obtain weather-resistant and flame-retardant polycarbonate / PBT composite material.

[0067] Example 4: This example discloses a method for preparing a composite weather-resistant agent, including the following steps:

[0068] Q1: Under nitrogen atmosphere, 0.94 g of di(trichloromethyl) carbonate was added to a container containing 15 mL of dichloromethane. After stirring and mixing, the mixture was cooled to -78 °C. Then, 15 mL of dichloromethane containing 1.36 g of pentafluoride (4-aminophenyl)sulfur and 1.04 g of triethylamine was added dropwise. The mixture was heated to 0 °C and reacted for 1 h. The mixture was then cooled to -78 °C. Subsequently, 15 mL of dichloromethane containing 2.08 g of 1-tert-butoxycarbonyl-4-aminomethylpiperidine and 1.04 g of triethylamine was added. The mixture was heated to 28 °C and reacted for 30 min. The mixture was then concentrated under reduced pressure at 40 °C. The mixture was purified using a 6:1 (v / v) mixture of petroleum ether and ethyl acetate as the eluent to obtain organic compound 1.

[0069] Q2: Add 0.76g of organic compound 1 to a container containing 6mL of a mixed solution of 2mol / L hydrochloric acid and 2.5mL of methanol. After hydrogenation at room temperature for 12h, concentrate under reduced pressure to obtain organic compound 2.

[0070] Q3: Add 0.32g of organic compound 2 to a container containing 9mL of acetonitrile, stir, then add 0.33g of potassium carbonate and 0.35g of 1,1,1-trifluoro-3-iodopropane. Heat to 60℃ and stir for 16h. Add distilled water, extract with ethyl acetate, dry with anhydrous sodium sulfate, concentrate under reduced pressure at 40℃, purify with a 7:1 (v / v) mixture of petroleum ether and ethyl acetate as the eluent, and dry to obtain the composite weathering agent.

[0071] This embodiment discloses a method for preparing a composite flame retardant, including the following steps:

[0072] S1: 0.613 g of cesium carbonate, 0.348 g of cuprous chloride, and 0.546 g of 5-bromo-2-pyridinecarboxaldehyde were added to a container containing 30 mL of N,N-dimethylformamide. After stirring at room temperature for 15 min, 10 mL of N,N-dimethylformamide containing 0.351 g of pyridine-2-methanethiol was added. The mixture was heated to reflux at 65 °C for 12 h. After the reaction was completed, the temperature was lowered to 28 °C, and the mixture was rotary evaporated. The product was dissolved in dichloromethane, washed with saturated sodium chloride, dried with anhydrous sodium sulfate, and purified using a mixed solution of petroleum ether and ethyl acetate in a volume ratio of 4:1 as the eluent to obtain product a.

[0073] S2: 0.936 g of product a and 0.678 g of aminotriazinone hydrochloride were added to a container containing 28 mL of methanol. The mixture was heated to reflux at 62 °C for 12 h, then cooled to 28 °C and rotary evaporated. The product was dissolved in dichloromethane and purified using a mixture of petroleum ether and ethyl acetate in a volume ratio of 3:1 as the eluent to obtain the composite flame retardant.

[0074] This embodiment discloses a weather-resistant and flame-retardant polycarbonate / PBT composite material, which is composed of the following components by weight: 45 parts polycarbonate, 52 parts polybutylene terephthalate, 0.6 parts composite weathering agent, 8 parts composite flame retardant, 0.9 parts polytetrafluoroethylene, 0.5 parts antioxidant 618, 7 parts ethylene-octene copolymer grafted maleic anhydride, 0.2 parts pentaerythritol stearate and 0.3 parts dispersant MG-555.

[0075] This embodiment discloses a method for preparing a weather-resistant and flame-retardant polycarbonate / PBT composite material, including the following steps:

[0076] Step 1: Add the dried polycarbonate and polybutylene terephthalate to the mixer and stir to mix. Then, add the composite weathering agent, antioxidant 618, pentaerythritol stearate and dispersant MG-555 in sequence and continue stirring. Then, add the composite flame retardant and ethylene-octene copolymer grafted maleic anhydride. Heat to 70°C and stir to mix for 5 minutes to obtain the dry mixture.

[0077] Step 2: Add the dry mixture to the main feed hopper of the twin-screw extruder, then add polytetrafluoroethylene through the side feed hopper. Heat and extrude the mixture. The temperature settings during the process are as follows: feeding section temperature 230℃, melting section temperature 250℃, mixing section temperature 260℃, metering section temperature 250℃, die head temperature 255℃, screw speed 500rpm, granulation, drying at 100℃ for 4 hours, screening, and packaging to obtain weather-resistant and flame-retardant polycarbonate / PBT composite material.

[0078] Example 5: This example discloses a method for preparing a composite weather-resistant agent, including the following steps:

[0079] Q1: Under nitrogen atmosphere, 0.87 g of di(trichloromethyl) carbonate was added to a container containing 15 mL of dichloromethane. After stirring and mixing, the mixture was cooled to -78 °C. Then, 15 mL of dichloromethane containing 1.56 g of pentafluoride (4-aminophenyl)sulfur and 1.04 g of triethylamine was added dropwise. The mixture was heated to 0 °C and reacted for 1 h. The mixture was then cooled to -78 °C. Subsequently, 15 mL of dichloromethane containing 1.98 g of 1-tert-butoxycarbonyl-4-aminomethylpiperidine and 1.04 g of triethylamine was added. The mixture was heated to 28 °C and reacted for 30 min. The mixture was then concentrated under reduced pressure at 40 °C. The mixture was purified using a 6:1 (v / v) mixture of petroleum ether and ethyl acetate as the eluent to obtain organic compound 1.

[0080] Q2: Add 0.81g of organic compound 1 to a container containing a mixture of 7mL hydrochloric acid with a concentration of 2mol / L and 3.5mL methanol. After hydrogenation at room temperature for 12h, concentrate under reduced pressure to obtain organic compound 2.

[0081] Q3: Add 0.29g of organic compound 2 to a container containing 11mL of acetonitrile, stir, then add 0.37g of potassium carbonate and 0.38g of 1,1,1-trifluoro-3-iodopropane. Heat to 60℃ and stir for 16h. Add distilled water, extract with ethyl acetate, dry with anhydrous sodium sulfate, concentrate under reduced pressure at 40℃, purify with a 7:1 volume ratio of petroleum ether and ethyl acetate as the eluent, and dry to obtain the composite weathering agent.

[0082] This embodiment discloses a method for preparing a composite flame retardant, including the following steps:

[0083] S1: 0.593 g of cesium carbonate, 0.357 g of cuprous chloride, and 0.568 g of 5-bromo-2-pyridinecarboxaldehyde were added to a container containing 30 mL of N,N-dimethylformamide. After stirring at room temperature for 15 min, 10 mL of N,N-dimethylformamide containing 0.372 g of pyridine-2-methanethiol was added. The mixture was heated to reflux at 65 °C for 12 h. After the reaction was completed, the temperature was lowered to 28 °C, and the mixture was rotary evaporated. The product was dissolved in dichloromethane, washed with saturated sodium chloride, dried with anhydrous sodium sulfate, and purified using a mixture of petroleum ether and ethyl acetate in a volume ratio of 4:1 as the eluent to obtain product a.

[0084] S2: 0.972 g of product a and 0.692 g of aminotriazinone hydrochloride were added to a container containing 32 mL of methanol. The mixture was heated to reflux at 62 °C for 12 h, then cooled to 28 °C and rotary evaporated. The product was dissolved in dichloromethane and purified using a mixture of petroleum ether and ethyl acetate in a volume ratio of 3:1 as the eluent to obtain the composite flame retardant.

[0085] This embodiment discloses a weather-resistant and flame-retardant polycarbonate / PBT composite material, which is composed of the following components by weight: 55 parts polycarbonate, 57 parts polybutylene terephthalate, 0.7 parts composite weathering agent, 7 parts composite flame retardant, 1.1 parts polytetrafluoroethylene, 0.7 parts antioxidant 1010, 11 parts ethylene-butyl acrylate-glycidyl methacrylate copolymer, 0.3 parts silicone oil, and 0.4 parts dispersant AS-220.

[0086] This embodiment discloses a method for preparing a weather-resistant and flame-retardant polycarbonate / PBT composite material, including the following steps:

[0087] Step 1: Add the dried polycarbonate and polybutylene terephthalate to the mixer and stir to mix. Then add the composite weathering agent, antioxidant 1010, silicone oil and dispersant AS-220 in sequence and continue stirring. Then add the composite flame retardant and ethylene-butyl acrylate-glycidyl methacrylate copolymer. Heat to 70°C and stir to mix for 5 minutes to obtain the dry mixture.

[0088] Step 2: Add the dry mixture to the main feed hopper of the twin-screw extruder, then add polytetrafluoroethylene through the side feed hopper. Heat and extrude the mixture. The temperature settings during the process are as follows: feeding section temperature 230℃, melting section temperature 250℃, mixing section temperature 260℃, metering section temperature 250℃, die head temperature 255℃, screw speed 500rpm, granulation, drying at 100℃ for 4 hours, screening, and packaging to obtain weather-resistant and flame-retardant polycarbonate / PBT composite material.

[0089] Comparative Example 1: Compared with Example 1, Comparative Example 1 did not add composite weathering agent during the preparation of composite material, and all other conditions remained unchanged.

[0090] Comparative Example 2: Compared with Example 1, Comparative Example 2 did not add composite flame retardant during the preparation of composite materials, and all other conditions remained unchanged.

[0091] Performance testing:

[0092] The composite materials prepared in Examples 1-5 and Comparative Examples 1-2 were subjected to performance tests. The combustion performance of the samples was tested according to GB / T 2408-2021, the hydrophobic and oleophobic properties were tested according to GB / T 30693-2014, and the weather resistance was tested according to GB / T 16422.3-2022. The test results are shown in Table 1.

[0093] Table 1

[0094]

[0095] As shown in Table 1, the test results indicate that composite materials with excellent flame retardant, hydrophobic, oleophobic, and weather-resistant properties can be prepared using the methods described in Examples 1-5. A comparison between Comparative Example 1 and Examples 1-5 reveals that the use of composite weathering agents effectively improves the weather resistance and hydrophobic / oleophobic properties of the composite materials; a comparison between Comparative Example 2 and Examples 1-5 shows that the use of composite flame retardants effectively improves the flame retardant properties of the composite materials.

[0096] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

[0097] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to specific implementations. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A weather-resistant and flame-retardant polycarbonate / PBT composite material, characterized in that, It is composed of the following components by weight: 40-60 parts polycarbonate, 48-62 parts polybutylene terephthalate, 0.3-0.8 parts composite weathering agent, 5-10 parts composite flame retardant, 0.8-1.2 parts polytetrafluoroethylene, 0.4-0.9 parts antioxidant, 6-12 parts toughening agent, 0.1-0.4 parts lubricant and 0.2-0.5 parts dispersant.

2. The weather-resistant and flame-retardant polycarbonate / PBT composite material according to claim 1, characterized in that, The preparation method of the composite weather-resistant agent, Includes the following steps: Q1: Under nitrogen atmosphere, di(trichloromethyl) carbonate was added to a container containing dichloromethane. After stirring and mixing, the mixture was cooled. Then, dichloromethane containing pentafluoride (4-aminophenyl)sulfur and triethylamine was added dropwise. After heating and reacting, the mixture was cooled again. Subsequently, dichloromethane containing 1-tert-butoxycarbonyl-4-aminomethylpiperidine and triethylamine was added. After heating and reacting, the mixture was concentrated under reduced pressure and purified to obtain organic compound 1. Q2: Organic compound 1 is added to a container containing a mixed solution of hydrochloric acid and methanol, hydrogenated at room temperature, and then concentrated under reduced pressure to obtain organic compound 2. Q3: Add organic compound 2 to a container containing acetonitrile, stir, then add potassium carbonate and 1,1,1-trifluoro-3-iodopropane, heat and stir to react, then add distilled water, extract, dry, concentrate under reduced pressure, purify, and dry to obtain a composite weathering agent.

3. The weather-resistant and flame-retardant polycarbonate / PBT composite material according to claim 2, characterized in that, In Q1, the ratio of di(trichloromethyl) carbonate, pentafluorinated (4-aminophenyl) sulfide, and 1-tert-butoxycarbonyl-4-aminomethylpiperidine is (0.85-0.97) g : (1.22-1.78) g : (1.96-2.14) g.

4. The weather-resistant and flame-retardant polycarbonate / PBT composite material according to claim 2, characterized in that, In Q2, the ratio of organic compound 1, hydrochloric acid and methanol is (0.72-0.83) g : (5-8) mL : (2-4) mL.

5. The weather-resistant and flame-retardant polycarbonate / PBT composite material according to claim 2, characterized in that, In Q3, the ratio of organic compound 2, acetonitrile, potassium carbonate and 1,1,1-trifluoro-3-iodopropane is (0.28-0.34) g : (8-12) mL : (0.31-0.38) g : (0.33-0.42) g.

6. The weather-resistant and flame-retardant polycarbonate / PBT composite material according to claim 1, characterized in that, The preparation method of the composite flame retardant includes the following steps: S1: Cesium carbonate, cuprous chloride, and 5-bromo-2-pyridinecarboxaldehyde were added to a container containing N,N-dimethylformamide. After stirring at room temperature, N,N-dimethylformamide containing pyridine-2-methanethiol was added, and the mixture was heated to reflux. After the reaction was completed, the mixture was cooled, rotary evaporated, dissolved, washed, dried, and purified to obtain product a. S2: Add product a and aminotriazinone hydrochloride to a container containing methanol, heat under reflux, cool, rotary evaporate, dissolve, and purify to obtain a composite flame retardant.

7. The weather-resistant and flame-retardant polycarbonate / PBT composite material according to claim 6, characterized in that, In S1, the ratio of cesium carbonate, cuprous chloride, 5-bromo-2-pyridinecarboxaldehyde, and pyridine-2-methanethiol is (0.588-0.625) g : (0.344-0.362) g : (0.532-0.571) g : (0.342-0.386) g.

8. The weather-resistant and flame-retardant polycarbonate / PBT composite material according to claim 6, characterized in that, In S2, the ratio of product a, aminotriazinone hydrochloride and methanol is (0.914-0.995) g : (0.674-0.698) g : (25-35) mL.

9. The method for preparing the weather-resistant and flame-retardant polycarbonate / PBT composite material according to any one of claims 1-8, characterized in that, Includes the following steps: Step 1: Add the dried polycarbonate and polybutylene terephthalate to the mixer, stir and mix, then add the composite weathering agent, antioxidant, lubricant and dispersant in sequence, continue stirring, then add the composite flame retardant and toughening agent, heat and stir to mix, and obtain the dry mixture. Step 2: Add the dry mixture to the main feed hopper of the twin-screw extruder, then add polytetrafluoroethylene through the side feed hopper, heat and extrude, granulate, dry, screen, and package to obtain a weather-resistant and flame-retardant polycarbonate / PBT composite material.

10. The method for preparing the weather-resistant and flame-retardant polycarbonate / PBT composite material according to claim 9, characterized in that, In step two, the temperatures during the heating and extrusion process are set as follows: feeding section temperature 220-240℃, melting section temperature 240-260℃, mixing section temperature 250-270℃, metering section temperature 240-260℃, die head temperature 250-265℃, and screw speed 300-600 rpm.

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