A polycarbonate composition and a method for producing the same

Abstract

This invention relates to a polycarbonate composition and its preparation method, which mainly comprises the following components, expressed in parts by weight: 65-85 parts aromatic polycarbonate, 15-35 parts phosphorus-silicon copolymer polycarbonate, 0.05-1 part antioxidant, and 0.1-1 part lubricant. The polycarbonate composition prepared by this invention is blended using a twin-screw extruder. The phosphorus-silicon copolymer polycarbonate and aromatic polycarbonate have good compatibility. Through the synergistic flame-retardant effect of phosphorus and silicon, the flame-retardant performance of the polycarbonate composite material is significantly improved, avoiding the use of halogen-free flame retardants and mitigating the reduction in mechanical properties of polycarbonate materials caused by small-molecule flame retardants. Furthermore, the siloxane segments significantly improve the low-temperature impact resistance of the material.

Description

TECHNICAL FIELD

[0001] The present application relates to a polycarbonate composition and a preparation method thereof, in particular, to a high-impact halogen-free flame-retardant polycarbonate composition and a preparation method thereof. BACKGROUND

[0002] Polycarbonate (PC) is a high molecular polymer containing carbonate bonds in the molecular chain, which can be divided into aliphatic, alicyclic, aliphatic-aromatic and aromatic polycarbonates. Among them, aromatic polycarbonate has excellent mechanical properties, heat resistance, impact toughness, electrical insulation and light transmission, and low creep resistance and water absorption, good dimensional stability, excellent dielectric properties, which can be used as a thermoplastic engineering plastic and widely used in automotive, electronic equipment, building, office supplies, optical discs, sports equipment, medical care, computers, aerospace and other fields. However, the unmodified polycarbonate material has poor flame retardant performance and low impact resistance at low temperature, which limits the application range of polycarbonate. Therefore, in order to expand its application range, it needs to be modified.

[0003] The main modification method at present is to add flame retardant to the polycarbonate matrix. The commonly used flame retardants for polycarbonate include halogen, phosphorus, silicon, sulfonate and the like. Halogen flame retardants will seriously affect the light transmission and impact strength of PC. Sulfonate flame retardants have good flame retardant effect and less influence on the light transmission of polycarbonate, but sulfonate contains sulfur element, which will cause harm to the environment and human body. Phosphorus flame retardant has low price, good flame retardant effect and is halogen-free and environmentally friendly, but the heat resistance of phosphorus flame retardant is poor and too much addition will directly affect the light transmission of polycarbonate. Organic silicon flame retardant has the characteristics of high efficiency, non-toxic, low smoke, anti-dripping, less influence on light transmission, processing performance and mechanical properties, but due to its high price, its use in industry is limited. Therefore, according to the current research status, adding a single flame retardant cannot meet the performance requirements of polycarbonate.

[0004] Chinese patent CN115124707A discloses a phosphorus-containing silicon copolymer polycarbonate and its preparation method and application. DOPO reacts with polysiloxane to introduce phosphorus-containing monomers into the side chain of polysiloxane, and then introduces them into the molecular chain of polycarbonate by chemical copolymerization. The compatibility of the prepared copolymer carbonate with aromatic polycarbonate needs to be further improved. Patent CN202110098391.5 discloses an intrinsic flame-retardant copolymer PC and its preparation method. Bisphenol S and siloxane segments are introduced into the conventional PC molecular chain to improve the intrinsic flame-retardant performance of PC. The highest flame-retardant level reaches UL94V0(3mm), but the impact performance of the material is poor. US20070129492 introduces siloxane monomers into the PC molecular chain to prepare a flame-retardant PC material with low smoke release and low heat release. The intrinsic flame-retardant performance reaches V0(3mm) and needs to be further improved. CN105849171B discloses a method for preparing a low-smoke and low-heat train interior component. The polymerization end is synthesized with a cyano phenol-terminated branched PC, a tetrabromobisphenol A copolymer PC, and a siloxane PC. The conventional PC and flame retardant additives are blended in a certain proportion. Blending can lead to the precipitation of flame retardants and affect the mechanical properties of the material.

[0005] In summary, it is necessary to develop an environmentally friendly high-impact halogen-free flame-retardant polycarbonate material with good compatibility with polycarbonate, which can compensate for the shortcomings of polycarbonate to some extent and broaden the application field of polycarbonate materials. SUMMARY

[0006] The purpose of the present application is to provide a polycarbonate composition and its preparation method. By introducing a polysiloxane and a phosphorus-containing bisphenol copolymer into the polycarbonate base material, the flame-retardant performance and impact resistance of the polycarbonate are improved.

[0007] The purpose of the present application can be achieved by the following technical means:

[0008] A polycarbonate composition, which comprises the following components (by weight):

[0009] (1) 65-85 parts by weight of aromatic polycarbonate;

[0010] (2) 15-35 parts by weight of phosphorus-silicon copolymer polycarbonate containing structural units of formula 1 and formula 2,

[0011]

[0012]

[0013] In formula 2, p is selected from an integer of 20-90, preferably 30-50;

[0014] (3) 0.05 to 1 part by weight of antioxidant;

[0015] (4) 0.1 to 1 part by weight of lubricant.

[0016] Preferably, the composition of the present invention comprises:

[0017] (1) 65-80 parts by weight of aromatic polycarbonate

[0018] (2) 20-35 parts by weight of phosphorus-silicon copolycarbonate containing structural units of formula 1 and formula 2

[0019] (3) 0.2 to 0.4 parts by weight of antioxidant

[0020] (4) 0.25 to 0.6 parts by weight of lubricant.

[0021] More preferably, the composition of the present invention comprises:

[0022] (1) 70-80 parts by weight of aromatic polycarbonate

[0023] (2) 20-30 parts by weight of phosphorus-silicon copolycarbonate containing structural units of formula 1 and formula 2

[0024] (3) 0.25 to 0.35 parts by weight of antioxidant

[0025] (4) 0.25 to 0.35 parts by weight of lubricant.

[0026] The aromatic polycarbonate is a bisphenol A type polycarbonate with a weight average molecular weight of 20,000-40,000; preferably, it is a bisphenol A type polycarbonate with a weight average molecular weight of 22,000-35,000.

[0027] The polycarbonate composition is characterized in that the phosphorus-silicon copolymer polycarbonate containing structural units of Formula 1 and Formula 2 has a weight percentage of 75-95%, preferably 80-90%, for the structural unit shown in Formula 1, and a weight percentage of 5-25%, preferably 10-20%, for the structural unit shown in Formula 2.

[0028] The phosphorus-silicon copolymer carbonate is obtained by polymerizing the phosphorus-containing bisphenol of Formula 3 and the phosphorus-containing polysiloxane monomer of Formula 4 with phosgene.

[0029]

[0030] In Formula 4, p is selected from an integer from 20 to 90, preferably from 30 to 50.

[0031] The weight-average molecular weight of the phosphorus-silicon copolycarbonate is 20,000-30,000 g / mol; preferably 25,000-30,000 g / mol.

[0032] The phosphorosilicate copolycarbonate containing structural units of Formula 1 and Formula 2 is prepared by the following method, which includes the following steps:

[0033] (1) Preparation of aqueous phase: Mix the phosphorus-containing bisphenol, end-capping agent, alkali metal hydroxide and water as shown in Formula 3. After the solid is completely dissolved, add the catalyst to form an aqueous phase.

[0034] (2) Preparation of comonomer solution: Liquid phosgene is mixed with an inert organic solvent in a mixer to prepare a phosgene solution. At the same time, the phosphorus-containing polyoxyalkylene monomer shown in Formula 4 is mixed with an inert organic solvent in another mixer to prepare a comonomer solution.

[0035] (3) Polymerization reaction: The prepared phosgene solution and comonomer solution are added dropwise to the aqueous phase to carry out the polymerization reaction, and the temperature of the reaction system is maintained at 30-35℃. After the reaction is carried out for 2-4 hours, a novel phosphosilicate copolycarbonate emulsion is obtained.

[0036] (4) Post-processing: The novel phosphorus-silicon copolycarbonate emulsion prepared in step (3) is purified and the organic solvent is removed to obtain the product;

[0037] In step (1), the capping agent is selected from one or more of phenol, p-tert-butylphenol, p-cumylphenol, and p-cyanophenol, preferably p-tert-butylphenol;

[0038] In step (1), the alkali metal hydroxide is selected from one or more of potassium hydroxide, sodium hydroxide, lithium hydroxide, and cesium hydroxide, preferably sodium hydroxide;

[0039] The molar ratio of the phosphorus-containing bisphenol: capping agent: alkali metal hydroxide: water is selected as 1:(0.01~0.03):(2.0-3.0):(25-50), preferably 1:(0.012~0.027):(2.2-3.0):(30-50);

[0040] The catalyst is triethylamine, tetrabutylammonium bromide, or tetrabutylammonium chloride, preferably tetrabutylammonium bromide; the molar ratio of the catalyst to phosphorus-containing bisphenol is 0.0001-0.006:1, preferably 0.0001-0.005:1;

[0041] In step (2), the inert organic solvent is selected from one or more of dichloromethane, trichloromethane, dichloroethane, and trichloroethane, preferably dichloromethane; the weight ratio of phosgene to inert organic solvent is 1:(5-40), preferably 1:(10-30); the weight ratio of comonomer to inert organic solvent is selected from 1:(3-6), preferably 1:(4-5);

[0042] The phosphorus-containing bisphenol of Formula 3 used in this invention is obtained by reacting o-diallyl bisphenol A with DOPO. DOPO, o-diallyl bisphenol A, ethanol, and a sodium hydroxide solution of a certain concentration are added to a reactor. The reaction is carried out for a period of time under a certain stirring rate and temperature. The solvent is removed by rotary evaporation to obtain the phosphorus-containing bisphenol monomer. The molar ratio of DOPO to o-diallyl bisphenol A is 1:1 to 20:1; the molar ratio of o-diallyl bisphenol A to ethanol is 1:10 to 1:40; the concentration of the sodium hydroxide solution is 10 to 40%; the molar ratio of o-diallyl bisphenol A to sodium hydroxide is 1:0.001 to 1:0.1; the stirring rate is 200 to 1000 rpm; the reaction temperature is 50 to 160°C; and the reaction time is 2 to 10 h. The reaction equation is shown in Formula 5.

[0043]

[0044] The polysiloxane comonomer shown in Formula 4 is obtained by reacting an allylphenol-terminated polysiloxane with DOPO. Specifically, DOPO, an allylphenol-terminated polysiloxane, ethanol, and sodium hydroxide solution are added to a reactor, and the reaction is carried out at a certain stirring rate and temperature. The solvent is removed by rotary evaporation to obtain a phosphorus-containing bisphenol monomer. The molar ratio of DOPO to the allylphenol-terminated polysiloxane is 1:1 to 20:1; the molar ratio of the allylphenol-terminated polysiloxane to ethanol is 1:10 to 1:40; the concentration of the sodium hydroxide solution is 10 to 40%; the molar ratio of the allylphenol-terminated polysiloxane to sodium hydroxide is 1:0.001 to 1:0.1; the stirring rate is 200 to 1000 rpm, the reaction temperature is 50 to 160°C, and the reaction time is 2 to 10 h. The reaction equation is shown in Formula 6.

[0045]

[0046] In step (3), the molar ratio of the added phosgene to the comonomer is (1.1-1.4):1, preferably (1.1-1.3):1;

[0047] The pH of the reaction system during the polymerization reaction is 11-12, preferably 11.5-11.7; the polymerization reaction is preferably carried out under stirring at a stirring rate of 500-800 rpm, preferably 600-800 rpm.

[0048] In step (4), the post-processing can be carried out using conventional methods in the art, such as: the copolymer emulsion is first subjected to oil-water separation, the oil phase is taken and washed with alkali, acid and water in sequence, the solvent is removed from the oil phase after water washing, and after pulverization and drying, phosphosilicon copolymer carbonate is obtained.

[0049] The antioxidant is any one or a combination of two or more of the hindered phenols, organophosphates, thioesters, and hindered amines; preferably, one or more of the antioxidant series 1076, 1010, 168, 421S, and 627 from Ciba are used.

[0050] The lubricant is any one or a combination of two or more of pentaerythritol stearate (PETS), modified ethylene bis-stearamide (modified EBS), and silicone powder.

[0051] On the other hand, the present invention also provides a method for preparing the high-impact, halogen-free, flame-retardant polycarbonate composition, the method comprising mixing 65-85 parts by weight of aromatic polycarbonate, 15-35 parts by weight of phosphorus-silicon copolymer polycarbonate, 0.05-1 parts by weight of antioxidant, and 0.1-1 parts by weight of lubricant in a high-speed mixer, and then extruding the mixture in a twin-screw extruder.

[0052] Preferably, the preparation method of the above-described high-impact halogen-free flame-retardant polycarbonate composition includes: mixing 65-85 parts by weight of aromatic polycarbonate, 15-35 parts by weight of phosphosilicon copolymer polycarbonate, 0.05-1 parts by weight of antioxidant, and 0.1-1 parts by weight of lubricant in a high-speed mixer; adding the mixture to a twin-screw extruder; controlling the temperature of the twin-screw extruder's conveying section at 210-220°C, the temperature of the plasticizing section at 225-245°C, and the temperature of the metering section at 225-240°C; controlling the screw speed at 200-600 rpm; controlling the vacuum degree of the vacuum device in the metering section of the twin-screw extruder to be less than -0.7 bar; and then drawing, water cooling, air drying, pelletizing, and drying to obtain the product.

[0053] The positive effects of this invention are as follows:

[0054] The polycarbonate composition of the present invention has excellent compatibility with polycarbonate materials, and through the synergistic flame retardant effect of phosphorus and silicon, the flame retardant performance of polycarbonate materials is greatly improved. It has halogen-free and environmentally friendly characteristics. Compared with small molecule flame retardants, it avoids the reduction of the mechanical properties of polycarbonate caused by the addition of flame retardants and the problem of small molecule migration. In addition, the phosphorus and silicon copolycarbonate added in the present invention forms large-size silicon domains in the polysiloxane segments, which can greatly improve the impact resistance of polycarbonate materials.

[0055] The compositions of the present invention have the following properties:

[0056] The impact strength (J / m) at room temperature is greater than 650, the impact strength (J / m) at -40℃ is greater than 550, and the flame retardant performance of the 1.5mm sample is V0 (UL94). Attached Figure Description

[0057] Figure 1BPA-P NMR spectrum

[0058] Figure 2 P-PDMS-55 NMR spectrum Detailed Implementation

[0059] To better understand the technical solution of the present invention, the following embodiments further illustrate the content of the present invention, but the content of the present invention is not limited to the following embodiments.

[0060] The analytical and evaluation methods involved in the embodiments or comparative examples are as follows:

[0061] (1) Molecular weight was determined by gel permeation chromatography (GPC) using a Waters 1515 gel permeation chromatograph, with tetrahydrofuran as solvent, PS as standard, temperature of 30℃ and time of 45 min.

[0062] (2) Impact strength was tested according to ASTM D256 standard. The sample size was 63.5*12.7*3.2mm and the notch depth was 2.5mm.

[0063] (3) Flame retardant properties

[0064] Flammability is evaluated according to Underwriter's Laboratory Bulletin 94, entitled "Tests for Flammability of Plastic Materials for Parts in Devices and Appliances" (ISBN 0-7629-0082-2), version 5, October 29, 1996, with all revisions and including the revision of December 12, 2003. Several classifications are applied based on burning rate, extinguishing time, resistance to dripping, and whether the drips are flammable. According to this specification, materials can be classified as UL94 HB, V0, V1, V2, 5VA, and / or 5VB;

[0065] (4) The content of siloxanes and phosphorus-containing bisphenol monomers was detected by 1H NMR spectroscopy;

[0066] Preliminary Example:

[0067] (1) Preparation of phosphorus-containing bisphenol monomer (DBA-P):

[0068] DOPO (10365g, 48mol), o-diallylbisphenol A (1478g, containing 9.60mol of double bond units), ethanol, and 32% sodium hydroxide solution (12g, 0.096mol) were added to the reactor. The mixture was mechanically stirred at 500rpm, heated to 80℃, and maintained for 4h. The solvent was removed by rotary evaporation to obtain the phosphorus-containing bisphenol monomer, named DBA-P.

[0069] (2) Preparation of polyorganosiloxane monomers:

[0070] Octamethylcyclotetrasiloxane (1420 g, 4.80 mol), tetramethyldisiloxane (40.2 g, 0.3 mol), and Filtrol 20 clay catalyst (23.4 g, 1.6 wt%) were added to a reactor equipped with a stirrer and thermometer and stirred for 40 minutes to homogenize the mixture. The reaction system was then heated to 50 °C at a rate of 5 °C / min and stirred at this temperature for 3 hours. Subsequently, the temperature of the reaction system was further increased to 120 °C at a rate of 5 °C / min and the reaction was vigorously stirred at this temperature for 5 hours. Afterward, the clay catalyst was removed by filtration. The material after removing the clay catalyst was then placed in a reactor equipped with a stirrer and thermometer, and a mixed solution of 2,4-divinylphenol (149 g, 1.02 mol) and Karstedt platinum catalyst (0.67 g) was added dropwise at a rate of 20 g / min with stirring. The reaction was then stirred at 80 °C for 13 hours. Unreacted raw materials were then removed by distillation at 200℃ under reduced pressure to 0.2 kPa to obtain vinylphenol-terminated polysiloxanes with a yield of 99%. The degree of polymerization of PDMS was determined to be 55 by NMR analysis, and for convenience, it is defined as PDMS-55 in this paper. With other conditions unchanged, by changing the amount of tetramethyldisiloxane, a monomer with a degree of polymerization of 89 siloxane was prepared (corresponding to 20.1 g of tetramethyldisiloxane), which is defined as PDMS-89 in this paper.

[0071] Further, DOPO (399.5 g 1.85 mol), PDMS-55 (1500 g 0.37 mol), ethanol, and 32% sodium hydroxide solution (4.6 g 0.037 mol) were mechanically stirred at 500 rpm, heated to 80 °C, and maintained for 4 h. The solvent was removed by rotary evaporation to obtain the phosphorus-containing polysiloxane monomer, named P-PDMS-55. P-PDMS-89 was prepared using the same method.

[0072] (3) Preparation of phosphorus-silicon copolycarbonate:

[0073] The preparation method of P-1 is as follows:

[0074] 7410g of phosphorus-containing bisphenol, 1000g of sodium hydroxide, 7200g of water, and 47g of p-tert-butylphenol were added to a nitrogen-protected mixer. After complete dissolution, 12.9g of tetrabutylammonium bromide catalyst was added to form a sodium phenolate salt water phase.

[0075] In another mixer, add 1139g of liquid phosgene and 22770g of dichloromethane (MC) and mix them thoroughly; then in another mixer, add 640g of phosphorus-containing polysiloxane monomer (P-PDMS-55) and 2562g of dichloromethane and mix them thoroughly.

[0076] The sodium phenolate brine phase was then placed into the polymerization reactor. Subsequently, the prepared phosgene solution and the prepared comonomer solution were added to the polymerization reactor at a stirring speed of 550 rpm. At the same time, a 32% by weight sodium hydroxide aqueous solution was added dropwise to the reaction system to maintain the pH value of the reaction system at 11.4, and the temperature of the reaction system was maintained at 35°C. After the reaction was completed for 2 hours, the reaction system was separated, purified, and the organic solvent was removed to obtain the phosphosilicate copolycarbonate of the present invention.

[0077] The preparation method for the other phosphorus-silicon copolycarbonates is the same as described in P-1 above, except that the feeding ratios are different, as shown in the table below:

[0078] Table 1 Feed ratio of phosphorus-silicon copolycarbonate

[0079]

[0080] The test data for the above manufacturing examples are shown in Table 2 below:

[0081] Table 2 Basic physical property test data

[0082]

[0083] The raw materials used in the examples and comparative examples are as follows:

[0084] (A) Aromatic polycarbonate:

[0085] PC-1 is a bisphenol A type polycarbonate powder with a weight average molecular weight of 22,000 produced by the interfacial phosgene method and manufactured by Wanhua Chemical Group Co., Ltd.

[0086] PC-2 is a bisphenol A type polycarbonate powder with a weight average molecular weight of 28,000 produced by the interfacial phosgene method and manufactured by Wanhua Chemical Group Co., Ltd.

[0087] PC-3 is a bisphenol A type polycarbonate powder with a weight average molecular weight of 34,000 produced by the interfacial phosgene method and manufactured by Wanhua Chemical Group Co., Ltd.

[0088] (B) Phosphosilicone copolymer carbonate

[0089] P-1 to P-6 were prepared in the preliminary examples described above;

[0090] P-7: Wanhua Chemical S2060 (MW: 28900g / mol, PDMS content 20%)

[0091] (C) Additives

[0092] The antioxidant B900 is produced by Ciba Specialty Chemicals.

[0093] Pentaerythritol stearate (PETS), a lubricant manufactured by Lonza Corporation, USA;

[0094] Examples and comparative examples:

[0095] The material preparation process is as follows:

[0096] Whether in comparative or exemplary cases, according to the corresponding formulation, aromatic polycarbonate, phosphosilicone copolymer carbonate, antioxidant, and lubricant are mixed and stirred in a high-speed mixer. The mixture is then added to a loss-in-weight feeder above the feed port of the screw extruder. The temperature of the twin-screw extruder is controlled at 210-220°C in the conveying section, 225-245°C in the plasticizing section, and 225-240°C in the metering section. The screw speed is controlled at 200-600 rpm. The vacuum degree of the vacuum device in the metering section of the twin-screw extruder is controlled to be less than -0.7 bar. The product is obtained by drawing, water cooling, air drying, pelletizing, and drying.

[0097] Examples 1-10

[0098] The formulations and properties of the polycarbonate compositions in Examples 1-10 are detailed in Table 1.

[0099] Comparative Examples 1-4

[0100] The formulations and properties of the polycarbonate compositions of Comparative Examples 1-4 are detailed in Table 2.

[0101] The polymer P-7 used in Comparative Example 4 was prepared according to Example 3 of Chinese Patent Publication CN112280027 A, with a measured molecular weight of 31000 g / mol and a siloxane content of 25%.

[0102] Table 1 Formulations and properties of the polycarbonate compositions in Examples 1-10

[0103]

[0104]

[0105] Table 2 Formulations and properties of the polycarbonate compositions in Comparative Examples 1-6

[0106]

[0107] Comparing Comparative Examples 1-4 with Examples 1, 2, 6, and 10, it was found that the phosphorus-silicon copolycarbonate in the polycarbonate composition of the present invention has good compatibility with the polycarbonate material. Through the synergistic flame retardant effect of phosphorus and silicon, the flame retardant performance of the polycarbonate material is greatly improved, and it has halogen-free and environmentally friendly characteristics. In addition, the phosphorus-silicon copolycarbonate added in the present invention forms large-size silicon domains in the polysiloxane segments, which can greatly improve the impact resistance of the polycarbonate material.

[0108] Those skilled in the art will understand that modifications or adjustments can be made to the present invention based on the teachings of this specification. These modifications or adjustments should also be within the scope defined by the claims of the present invention.

Claims

1. A polycarbonate composition comprising at least the following four components: (1) 65 to 85 parts by weight of aromatic polycarbonate; (2) 15 to 35 parts by weight of phosphorus-silicon copolymer carbonate containing structural units of formula 1 and formula 2, Formula 1 Formula 2 In Equation 2, p is selected from integers from 20 to 90; (3) 0.05 to 1 part by weight of antioxidant; (4) 0.1 to 1 parts by weight of lubricant.

2. The polycarbonate composition according to claim 1, characterized in that, p is an integer between 30 and 50.

3. The polycarbonate composition according to claim 1, characterized in that, The aromatic polycarbonate is a bisphenol A type polycarbonate with a weight average molecular weight of 20,000-40,000 g / mol.

4. The polycarbonate composition according to claim 1, characterized in that, The aromatic polycarbonate is a bisphenol A type polycarbonate with a weight average molecular weight of 22,000-35,000 g / mol.

5. The polycarbonate composition according to any one of claims 1-4, characterized in that, The phosphorus-silicon copolycarbonate has a weight-average molecular weight of 20,000-30,000 g / mol.

6. The polycarbonate composition according to claim 5, characterized in that, The phosphorus-silicon copolycarbonate has a weight-average molecular weight of 25,000-30,000 g / mol.

7. The polycarbonate composition according to any one of claims 1-4, characterized in that, The phosphorus-silicon copolymer carbonate is obtained by polymerizing the phosphorus-containing bisphenol of Formula 3 and the phosphorus-containing polysiloxane monomer of Formula 4 with phosgene. Formula 3, Formula 4.

8. The polycarbonate composition according to any one of claims 1-4, characterized in that, The antioxidant is any one or a mixture of two or more of the hindered phenols, organophosphates, thioesters or hindered amines.

9. The polycarbonate composition according to any one of claims 1-4, characterized in that, The lubricant is any one or a mixture of two or more of pentaerythritol stearate, modified ethylene bis-stearamide, and silicone powder.

10. A method for preparing the polycarbonate composition according to any one of claims 1-9, the method comprising: Aromatic polycarbonate, phosphosilicon copolycarbonate, antioxidant, and lubricant are mixed in a high-speed mixer, and then the mixture is extruded in a twin-screw extruder.

11. The preparation method according to claim 10, characterized in that, The temperature of the conveying section of the twin-screw extruder is 210-220℃, the temperature of the plasticizing section is 225-245℃, the temperature of the metering section is 225-240℃, and the screw speed is 200-600 rpm.

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