PC material for automobile thin-wall injection molded part and preparation method

Abstract

The invention relates to the technical field of materials for vehicles, and discloses a PC (polycarbonate) material for an automobile thin-wall injection molded part, which comprises the following components: polycarbonate, acrylonitrile-butadiene-styrene, glass fiber, a flexibilizer, a lubricant, a compatilizer, a processing aid and a flame retardant. According to the invention, polycarbonate with a mixing ratio of 6: 4 is prepared by adopting a phosgene polymerization process and a transesterification process, so that the flowability and impact property of the PC material are more excellent, the flowability and impact strength of the material are improved, and by adopting the flexibilizer formed by mixing MBS of a silicon-based acrylic acid base material and MBS of a butadiene base material, the impact strength of the material is improved. According to the present invention, the core-shell system MBS materials with two different base materials produce the synergistic effect, such that the PC material has the high toughening effect, and the impact strength of the PC material is further improved so as to effectively improve the use effect of the PC material in the field of automobile thin-wall injection molding parts.

Description

Technical Field

[0001] The present invention relates to the technical field of automotive materials, and in particular to a PC material for automotive thin-wall injection molding parts and a preparation method thereof. Background Art

[0002] Polycarbonate (PC, also known as PC plastic), one of the five major engineering plastics, has become an indispensable key material in the automotive, electronics, construction, medical equipment, and other fields due to its excellent impact resistance, high transparency, and good heat resistance. With global industrial upgrades and increasing environmental protection requirements, PC materials are developing towards high-performance, green, and functional materials. Since its industrial production in the 1950s, PC has been widely used in various industrial fields due to its excellent comprehensive performance.

[0003] In the automotive manufacturing industry, PC materials have gradually become irreplaceable key materials due to their unique performance advantages. With the rapid development of the automotive industry towards lightweight, intelligent and electrified directions, the performance requirements for engineering plastics are constantly increasing, especially in the field of thin-walled injection molding parts. Traditional PC materials have been unable to meet the increasingly stringent processing and use requirements. Thin-wall injection molding technology, as an important process for the manufacture of modern automotive parts, puts forward dual requirements of high fluidity and high toughness for materials. At present, in the selection of PC substrates for automotive thin-walled injection molding parts, domestic high-flow PC often has the problem of too wide molecular weight distribution, resulting in defects such as narrow processing window and large fluctuations in product performance. The high activity of the end group will cause the material to degrade during high-temperature processing, resulting in poor fluidity of the material, and the impact strength of thin-walled injection molding parts is poor after the thickness is reduced. To this end, we provide a PC material for automotive thin-walled injection molding parts to solve this problem. Summary of the Invention

[0004] In view of the deficiencies in the prior art, the present invention provides a PC material for automotive thin-wall injection molding parts and a preparation method to solve this problem.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a PC material for automotive thin-wall injection molding parts, comprising the following components: polycarbonate, acrylonitrile-butadiene-styrene, glass fiber, a toughening agent, a lubricant, a compatibilizer, a processing aid, and a flame retardant. The components of the material, by weight percentage, are as follows: 27-60% polycarbonate, 8-18% acrylonitrile-butadiene-styrene, 2-4% glass fiber, 8-14% toughening agent, 7-11% lubricant, 6-9% compatibilizer, 8-14% processing aid, and 1-3% flame retardant.

[0006] As a further solution of the present invention: the polycarbonate is produced by either or both of the two processes of phosgene polymerization and transesterification.

[0007] As a further solution of the present invention: the toughening agent is composed of a mixture of silicone-based acrylic-based MBS and butadiene-based MBS.

[0008] As a further embodiment of the present invention: the lubricant is selected from any two or more of stearate, fatty amide, and silicone.

[0009] As a further solution of the present invention: the compatibilizer is selected from any two or more of PP grafting, POE grafting, and EPDM grafting.

[0010] As a further solution of the present invention: the diameter of the glass fiber is an alkali-free short glass fiber with a diameter of 4-7 μm.

[0011] As a further solution of the present invention: the processing aid is selected from any two or more of hindered phenols, thioesters, phosphites, and weathering agents.

[0012] As a further embodiment of the present invention: the flame retardant is selected from any one or two of phosphates and phosphonates.

[0013] The present invention also provides a method for preparing PC material for automotive thin-wall injection molding parts, comprising the following steps:

[0014] S1. Material preparation: Prepare sufficient amounts of polycarbonate raw materials by phosgene polymerization and transesterification respectively;

[0015] S2. Material preparation: The polycarbonate raw materials and acrylonitrile-butadiene-styrene raw materials manufactured by the two processes are ultrasonically cleaned in water at a temperature of 20-40° C. for 4-15 minutes, then rinsed with deionized water, and then dried in a dryer for 2-4 hours at a temperature of 85-95° C.;

[0016] S3. Ingredients: Weigh various raw materials according to the weight percentage of the formula components of this PC material, namely 27-60% polycarbonate, 8-18% acrylonitrile-butadiene-styrene, 2-4% glass fiber, 8-14% toughening agent, 7-11% lubricant, 6-9% compatibilizer, 8-14% processing aid, and 1-3% flame retardant;

[0017] S4, raw material mixing: put the various raw materials in S3 into a mixing barrel according to weight percentage and stir and mix them thoroughly at a speed of 200-400 rpm for 10-20 min to obtain a mixed material;

[0018] S5. Feeding and melting: Add the mixed material into the twin-screw extruder, and control the barrel temperature of the twin-screw extruder at 220-270°C;

[0019] S6. Finished product preparation: The PC material is extruded through a twin-screw extruder, and is drawn into strips and water-cooled before being drawn into shape. The formed material is then pelletized through a pelletizer to obtain PC material for automotive thin-walled injection molding parts.

[0020] Compared with the prior art, the present invention provides a PC material and preparation method for automotive thin-wall injection molding parts, which has the following beneficial effects:

[0021] 1. The PC material used for automotive thin-wall injection molding parts is made by using a 6:4 mixed ratio of polycarbonate produced by phosgene polymerization and transesterification, which makes the PC material more fluid and has better impact properties, thereby improving the material's fluidity and impact strength.

[0022] 2. This PC material for automotive thin-wall injection molding uses a toughening agent composed of a mixture of silicone-based acrylic MBS and butadiene-based MBS. The two core-shell MBS materials with different base materials produce a synergistic effect, resulting in a higher toughening effect on the PC material and further increasing the impact strength of the PC material.

[0023] 3. The PC material for automotive thin-wall injection moldings further increases the tensile effect of the PC material by compounding two or more base materials of stearate, fatty amide, and silicone. The antioxidant effect of the PC material is further increased by compounding two or more base materials of hindered phenols, thioesters, phosphites, and weathering agents. The flame retardant effect of the PC material is improved by adding one or both of phosphates and phosphonates, thereby effectively increasing the use effect of the PC material in the field of automotive thin-wall injection moldings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the preparation process of PC material for automotive thin-wall injection molding parts proposed by the present invention. DETAILED DESCRIPTION

[0025] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0026] Example 1

[0027] A PC material for thin-walled injection molding parts of automobiles comprises the following components by weight: 27% polycarbonate, 18% acrylonitrile-butadiene-styrene, 4% glass fiber, 14% toughening agent, 11% lubricant, 9% compatibilizer, 14% processing aid, and 3% flame retardant.

[0028] Reference Figure 1 A method for preparing PC material for thin-walled injection molding of automobiles comprises the following steps:

[0029] S1. Material preparation: Produce sufficient polycarbonate raw materials according to the phosgene polymerization process;

[0030] S2. Material preparation: The polycarbonate raw material and the acrylonitrile-butadiene-styrene raw material were ultrasonically cleaned in water at a temperature of 20° C. for 4 minutes, then rinsed with deionized water, and then dried in a dryer at a temperature of 85° C. for 2 hours.

[0031] S3. Ingredients: Weigh various raw materials according to the weight percentage of the formula components of this PC material, namely 27% of polycarbonate produced by phosgene polymerization process, 18% of acrylonitrile-butadiene-styrene, 4% of alkali-free short glass fiber with a diameter of 4 μm, 14% of a toughening agent composed of a mixture of MBS with a silicone-based acrylic base and MBS with a butadiene base, 11% of a lubricant composed of a mixture of stearate and silicone, 9% of a compatibilizer composed of a mixture of PP grafting and EPDM grafting, 14% of a processing aid composed of a mixture of hindered phenols and phosphites, and 3% of a flame retardant selected from phosphate esters;

[0032] S4, raw material mixing: put the various raw materials in S3 into a mixing barrel according to weight percentage and stir and mix them thoroughly at a speed of 200 rpm for 10 min to obtain a mixed material;

[0033] S5. Feeding and melting: adding the mixed material into the twin-screw extruder, and controlling the barrel temperature of the twin-screw extruder at 220°C;

[0034] S6. Finished product preparation: The PC material is extruded through a twin-screw extruder, and is drawn into strips and water-cooled before being drawn into shape. The formed material is then pelletized through a pelletizer to obtain PC material for automotive thin-walled injection molding parts.

[0035] Example 2

[0036] A PC material for thin-walled injection molding parts of automobiles comprises the following components by weight: 41% polycarbonate, 14% acrylonitrile-butadiene-styrene, 3% glass fiber, 10% toughening agent, 10% lubricant, 8% compatibilizer, 12% processing aid, and 2% flame retardant.

[0037] Reference Figure 1 A method for preparing PC material for thin-walled injection molding of automobiles comprises the following steps:

[0038] S1. Material preparation: Produce sufficient polycarbonate raw materials according to the transesterification process;

[0039] S2. Material preparation: The polycarbonate raw material and the acrylonitrile-butadiene-styrene raw material were ultrasonically cleaned in water at a temperature of 30° C. for 8 minutes, then rinsed with deionized water, and then dried in a dryer at a temperature of 90° C. for 3 hours.

[0040] S3. Ingredients: Weigh various raw materials according to the weight percentage of the formula components of this PC material, namely 41% of polycarbonate manufactured by the ester exchange process, 14% of acrylonitrile-butadiene-styrene, 3% of alkali-free short glass fiber with a diameter of 5 μm, 10% of a toughening agent composed of a mixture of MBS with a silicone-based acrylic base and MBS with a butadiene base, 10% of a lubricant composed of a mixture of stearate and fatty amide, 8% of a compatibilizer composed of a mixture of PP grafting and POE grafting, 12% of a processing aid composed of a mixture of hindered phenols, thioesters and phosphites, and 2% of a flame retardant selected from phosphonates;

[0041] S4, raw material mixing: put the various raw materials in S3 into a stirring barrel according to weight percentage and stir and mix them thoroughly at a speed of 300 rpm for 15 min to obtain a mixed material;

[0042] S5. Feeding and melting: adding the mixed material into the twin-screw extruder, and controlling the barrel temperature of the twin-screw extruder at 250°C;

[0043] S6. Finished product preparation: The PC material is extruded through a twin-screw extruder, and is drawn into strips and water-cooled before being drawn into shape. The formed material is then pelletized through a pelletizer to obtain PC material for automotive thin-walled injection molding parts.

[0044] Example 3

[0045] A PC material for thin-walled injection molding parts of automobiles comprises the following components by weight: 52% polycarbonate, 12% acrylonitrile-butadiene-styrene, 2% glass fiber, 9% toughening agent, 8% lubricant, 6% compatibilizer, 10% processing aid, and 1% flame retardant.

[0046] Reference Figure 1 A method for preparing PC material for thin-walled injection molding of automobiles comprises the following steps:

[0047] S1. Material preparation: Produce sufficient polycarbonate raw materials according to the phosgene polymerization and transesterification processes;

[0048] S2. Material preparation: The polycarbonate raw material and the acrylonitrile-butadiene-styrene raw material were ultrasonically cleaned in water at a temperature of 40° C. for 12 minutes, then rinsed with deionized water, and then dried in a dryer at a temperature of 95° C. for 3 hours.

[0049] S3. Ingredients: Weigh various raw materials according to the weight percentage of the formula components of this PC material, namely 51% of polycarbonate selected from the phosgene polymerization and ester exchange process in a 1:1 mixed ratio, 12% of acrylonitrile-butadiene-styrene, 2% of alkali-free short glass fiber with a diameter of 6 μm, 9% of a toughening agent selected from a mixture of MBS with a silicone-based acrylic matrix and MBS with a butadiene matrix, 8% of a lubricant selected from a mixture of stearate, fatty amide and silicone, 6% of a compatibilizer selected from a mixture of PP grafting, POE grafting and EPDM grafting, 10% of a processing aid selected from a mixture of a weathering agent, a thioester and a phosphite, and 1% of a flame retardant selected from a mixture of a phosphate and a phosphonate;

[0050] S4, raw material mixing: put the various raw materials in S3 into a mixing barrel according to weight percentage and stir and mix them thoroughly at a speed of 400 rpm for 15 min to obtain a mixed material;

[0051] S5. Feeding and melting: adding the mixed material into the twin-screw extruder, and controlling the barrel temperature of the twin-screw extruder at 270°C;

[0052] S6. Finished product preparation: The PC material is extruded through a twin-screw extruder, and is drawn into strips and water-cooled before being drawn into shape. The formed material is then pelletized through a pelletizer to obtain PC material for automotive thin-walled injection molding parts.

[0053] Example 4

[0054] A PC material for thin-walled injection molding parts of automobiles comprises the following components by weight: 60% polycarbonate, 8% acrylonitrile-butadiene-styrene, 2% glass fiber, 8% toughening agent, 7% lubricant, 6% compatibilizer, 8% processing aid, and 1% flame retardant.

[0055] Reference Figure 1 A method for preparing PC material for thin-walled injection molding of automobiles comprises the following steps:

[0056] S1. Material preparation: Produce sufficient polycarbonate raw materials according to the phosgene polymerization and transesterification processes;

[0057] S2. Material preparation: The polycarbonate raw material and the acrylonitrile-butadiene-styrene raw material were ultrasonically cleaned in water at a temperature of 40° C. for 15 minutes, then rinsed with deionized water, and then dried in a dryer at a temperature of 95° C. for 4 hours.

[0058] S3. Ingredients: Weigh various raw materials according to the weight percentage of the formula components of this PC material, namely 60% of polycarbonate with a 6:4 mixed ratio selected from phosgene polymerization and ester exchange processes, 8% of acrylonitrile-butadiene-styrene, 2% of alkali-free short glass fiber with a diameter of 7 μm, 8% of a toughening agent selected from a mixture of MBS with a silicone-based acrylic matrix and MBS with a butadiene matrix, 7% of a lubricant selected from a mixture of stearate and silicone, 6% of a compatibilizer selected from a mixture of POE grafting and EPDM grafting, 8% of a processing aid selected from a mixture of hindered phenols, weathering agents, thioesters and phosphites, and 1% of a flame retardant selected from a mixture of phosphates and phosphonates;

[0059] S4, raw material mixing: put the various raw materials in S3 into a mixing barrel according to weight percentage and stir and mix them thoroughly at a speed of 400 rpm for 20 min to obtain a mixed material;

[0060] S5. Feeding and melting: adding the mixed material into the twin-screw extruder, and controlling the barrel temperature of the twin-screw extruder at 270°C;

[0061] S6. Finished product preparation: The PC material is extruded through a twin-screw extruder, and is drawn into strips and water-cooled before being drawn into shape. The formed material is then pelletized through a pelletizer to obtain PC material for automotive thin-walled injection molding parts.

[0062] Comparative Example 1

[0063] A PC material for thin-walled injection molding parts of automobiles comprises the following components by weight: 60% polycarbonate, 8% acrylonitrile-butadiene-styrene, 2% glass fiber, 8% toughening agent, 7% lubricant, 6% compatibilizer, 8% processing aid, and 1% flame retardant.

[0064] Reference Figure 1 A method for preparing PC material for thin-walled injection molding of automobiles comprises the following steps:

[0065] S1. Material preparation: Prepare sufficient amount of polycarbonate raw material according to the non-phosgene transesterification melt polycondensation method;

[0066] S2. Material preparation: The polycarbonate raw material and the acrylonitrile-butadiene-styrene raw material were ultrasonically cleaned in water at a temperature of 40° C. for 15 minutes, then rinsed with deionized water, and then dried in a dryer at a temperature of 95° C. for 4 hours.

[0067] S3. Ingredients: Weigh various raw materials according to the weight percentage of the formula components of this PC material, namely 60% of polycarbonate produced by non-phosgene transesterification melt polycondensation method, 8% of acrylonitrile-butadiene-styrene, 2% of glass fiber selected from alkali-free short glass fiber with a diameter of 7 μm, 8% of a toughening agent selected from a mixture of MBS with a silicone-based acrylic matrix and MBS with a butadiene matrix, 7% of a lubricant selected from a mixture of stearate and silicone, 6% of a compatibilizer selected from a mixture of POE grafted and EPDM grafted, 8% of a processing aid selected from a mixture of hindered phenols, weathering agents, thioesters and phosphites, and 1% of a flame retardant selected from a mixture of phosphates and phosphonates;

[0068] S4, raw material mixing: put the various raw materials in S3 into a mixing barrel according to weight percentage and stir and mix them thoroughly at a speed of 400 rpm for 20 min to obtain a mixed material;

[0069] S5. Feeding and melting: adding the mixed material into the twin-screw extruder, and controlling the barrel temperature of the twin-screw extruder at 270°C;

[0070] S6. Finished product preparation: The PC material is extruded through a twin-screw extruder, and is drawn into strips and water-cooled before being drawn into shape. The formed material is then pelletized through a pelletizer to obtain PC material for automotive thin-walled injection molding parts.

[0071] Comparative Example 2

[0072] A PC material for thin-walled injection molding parts of automobiles comprises the following components by weight: 60% polycarbonate, 8% acrylonitrile-butadiene-styrene, 2% glass fiber, 8% toughening agent, 7% lubricant, 6% compatibilizer, 8% processing aid, and 1% flame retardant.

[0073] Reference Figure 1 A method for preparing PC material for thin-walled injection molding of automobiles comprises the following steps:

[0074] S1. Material preparation: Produce sufficient polycarbonate raw materials according to the phosgene polymerization and transesterification processes;

[0075] S2. Material preparation: The polycarbonate raw material and the acrylonitrile-butadiene-styrene raw material were ultrasonically cleaned in water at a temperature of 40° C. for 15 minutes, then rinsed with deionized water, and then dried in a dryer at a temperature of 95° C. for 4 hours.

[0076] S3. Ingredients: Weigh various raw materials according to the weight percentage of the formula components of this PC material, namely 60% of polycarbonate with a 6:4 mixed ratio selected from phosgene polymerization and ester exchange process, 8% of acrylonitrile-butadiene-styrene, 2% of alkali-free short glass fiber with a diameter of 7um, 8% of MBS toughening agent selected from silicone-based acrylic matrix, 7% of lubricant selected from a mixture of stearate and silicone, 6% of compatibilizer selected from a mixture of POE grafted and EPDM grafted, 8% of processing aid selected from a mixture of hindered phenols, weathering agents, thioesters and phosphites, and 1% of flame retardant selected from a mixture of phosphates and phosphonates;

[0077] S4, raw material mixing: put the various raw materials in S3 into a mixing barrel according to weight percentage and stir and mix them thoroughly at a speed of 400 rpm for 20 min to obtain a mixed material;

[0078] S5. Feeding and melting: adding the mixed material into the twin-screw extruder, and controlling the barrel temperature of the twin-screw extruder at 270°C;

[0079] S6. Finished product preparation: The PC material is extruded through a twin-screw extruder, and is drawn into strips and water-cooled before being drawn into shape. The formed material is then pelletized through a pelletizer to obtain PC material for automotive thin-walled injection molding parts.

[0080] Comparative Example 3

[0081] A PC material for thin-walled injection molding parts of automobiles comprises the following components by weight: 60% polycarbonate, 8% acrylonitrile-butadiene-styrene, 2% glass fiber, 8% toughening agent, 7% lubricant, 6% compatibilizer, 8% processing aid, and 1% flame retardant.

[0082] Reference Figure 1 A method for preparing PC material for thin-walled injection molding of automobiles comprises the following steps:

[0083] S1. Material preparation: Produce sufficient polycarbonate raw materials according to the phosgene polymerization and transesterification processes;

[0084] S2. Material preparation: The polycarbonate raw material and the acrylonitrile-butadiene-styrene raw material were ultrasonically cleaned in water at a temperature of 40° C. for 15 minutes, then rinsed with deionized water, and then dried in a dryer at a temperature of 95° C. for 4 hours.

[0085] S3. Ingredients: Weigh various raw materials according to the weight percentage of the formula components of this PC material, namely 60% of polycarbonate with a 6:4 mixed ratio selected from phosgene polymerization and ester exchange processes, 8% of acrylonitrile-butadiene-styrene, 2% of alkali-free short glass fiber with a diameter of 7 μm, 8% of a toughening agent selected from a mixture of MBS with a silicone-based acrylic matrix and MBS with a butadiene matrix, 7% of a lubricant selected from fatty amides, 6% of a compatibilizer selected from a mixture of POE grafting and EPDM grafting, 8% of a processing aid selected from a mixture of hindered phenols, weathering agents, thioesters and phosphites, and 1% of a flame retardant selected from a mixture of phosphates and phosphonates;

[0086] S4, raw material mixing: put the various raw materials in S3 into a mixing barrel according to weight percentage and stir and mix them thoroughly at a speed of 400 rpm for 20 min to obtain a mixed material;

[0087] S5. Feeding and melting: adding the mixed material into the twin-screw extruder, and controlling the barrel temperature of the twin-screw extruder at 270°C;

[0088] S6. Finished product preparation: The PC material is extruded through a twin-screw extruder, and is drawn into strips and water-cooled before being drawn into shape. The formed material is then pelletized through a pelletizer to obtain PC material for automotive thin-walled injection molding parts.

[0089] Comparative Example 4

[0090] A PC material for thin-walled injection molding parts of automobiles comprises the following components by weight: 60% polycarbonate, 8% acrylonitrile-butadiene-styrene, 2% glass fiber, 8% toughening agent, 7% lubricant, 6% compatibilizer, 8% processing aid, and 1% flame retardant.

[0091] Reference Figure 1 A method for preparing PC material for thin-walled injection molding of automobiles comprises the following steps:

[0092] S1. Material preparation: Produce sufficient polycarbonate raw materials according to the phosgene polymerization and transesterification processes;

[0093] S2. Material preparation: The polycarbonate raw material and the acrylonitrile-butadiene-styrene raw material were ultrasonically cleaned in water at a temperature of 40° C. for 15 minutes, then rinsed with deionized water, and then dried in a dryer at a temperature of 95° C. for 4 hours.

[0094] S3. Ingredients: Weigh various raw materials according to the weight percentage of the formula components of this PC material, namely 60% of polycarbonate with a 6:4 mixed ratio selected from phosgene polymerization and ester exchange processes, 8% of acrylonitrile-butadiene-styrene, 2% of alkali-free short glass fiber with a diameter of 7 μm, 8% of a toughening agent selected from a mixture of MBS with a silicone-based acrylic base and MBS with a butadiene base, 7% of a lubricant selected from a mixture of stearate and silicone, 6% of a compatibilizer selected from a mixture of POE grafted and EPDM grafted, 8% of a processing aid selected from thioesters, and 1% of a flame retardant selected from a mixture of phosphates and phosphonates;

[0095] S4, raw material mixing: put the various raw materials in S3 into a mixing barrel according to weight percentage and stir and mix them thoroughly at a speed of 400 rpm for 20 min to obtain a mixed material;

[0096] S5. Feeding and melting: adding the mixed material into the twin-screw extruder, and controlling the barrel temperature of the twin-screw extruder at 270°C;

[0097] S6. Finished product preparation: The PC material is extruded through a twin-screw extruder, and is drawn into strips and water-cooled before being drawn into shape. The formed material is then pelletized through a pelletizer to obtain PC material for automotive thin-walled injection molding parts.

[0098] The samples of the low-floating fiber PP composite materials for automobiles prepared in Examples 1-4 and Comparative Examples 1-4 were taken for performance and appearance tests. The specific test results are shown in the figure below:

[0099]

[0100]

[0101] Combined with the above test results, it can be seen that when Examples 1-3 and Comparative Example 1 are compared with Example 4, when Example 1 adopts the phosgene polymerization process to manufacture polycarbonate, the molecular weight control of the polycarbonate is narrower, and the end group capping technology is more excellent. Therefore, the stability of the material is good, the notched impact test result is good, which is intended to illustrate that the toughness of the material is high, and the melt index is medium, which is intended to illustrate that the fluidity of the material is good. When Example 2 adopts the ester exchange method to manufacture polycarbonate, the molecular weight of the polycarbonate is wider and the melt index is low, which leads to poor fluidity of the material, but the high molecular weight polycarbonate provides more efficient impact performance, and the notched impact test result is good, which is intended to illustrate that the toughness of the material is high. The non-phosgene ester exchange melt polycondensation method used in Comparative Example 1 is used to manufacture polycarbonate. The notched impact test result of the polycarbonate produced by the phosgene polymerization and ester exchange process is good, indicating that the material has high toughness, but low melt index, indicating that the material has poor fluidity. The notched impact test result of the polycarbonate produced by the phosgene polymerization and ester exchange process in Example 3 with a 1:1 mixed ratio is excellent, indicating that the material has high toughness, but medium melt index, indicating that the material has good fluidity. The notched impact test result of the polycarbonate produced by the phosgene polymerization and ester exchange process in Example 4 with a 6:4 mixed ratio is excellent, indicating that the material has high toughness, but high melt index, indicating that the material has high fluidity. This is intended to illustrate that when the polycarbonate polymerized by the phosgene method is mixed and compounded with the polycarbonate produced by the ester exchange method in a 6:4 ratio, a polycarbonate with excellent fluidity and impact performance can be obtained.

[0102] Comparing Comparative Example 2 with Example 4, the MBS toughening agent with a silicone-based acrylic substrate used in Comparative Example 2 has a good notched impact test result, indicating that the material has high toughness, while the toughening agent composed of a mixture of MBS with a silicone-based acrylic substrate and MBS with a butadiene substrate used in Example 4 has an excellent notched impact test result, indicating that the material has high toughness. This is intended to illustrate that the shell-core system MBS materials of the two different substrates produce a synergistic effect, resulting in a higher toughening effect of the material.

[0103] Comparative Example 3 is compared with Examples 1-4. Comparative Example 3 uses a fatty amide lubricant, and the tensile test results are poor, indicating that the tensile effect of the material is poor, while Examples 1-4 use two or three mixed compounds, and their tensile test results are all excellent, indicating that the tensile effect of the material is excellent, which is intended to illustrate that the compounding effect of two or more base materials between stearate, fatty amide and silicone is higher than the lubricating effect of fatty amide.

[0104] Comparative Example 4 is compared with Examples 1-4. Comparative Example 4 uses a thioester processing aid, and the antioxidant detection structure is poor, indicating that the antioxidant effect of the material is poor, while Examples 1-4 use a mixed compound of two or more substrates, and the antioxidant detection structure is excellent, indicating that the antioxidant effect of the material is excellent, which is intended to illustrate that the compounding effect of two or more substrates between hindered phenols, thioesters and phosphites, and weathering agents is higher than the antioxidant effect of a single thioester substrate.

[0105] The flame retardant test results of one or both of the phosphate and phosphonate flame retardants used in Examples 1-4 and Comparative Examples 1-4 are excellent, indicating that the flame retardant effect of the materials is excellent, which is intended to illustrate that the flame retardant effect of phosphate and phosphonate is excellent.

[0106] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A PC material for automotive thin-wall injection molding parts, comprising the following components: polycarbonate, acrylonitrile-butadiene-styrene, glass fiber, a toughening agent, a lubricant, a compatibilizer, a processing aid, and a flame retardant, characterized in that: The material comprises the following components by weight: 27-60% polycarbonate, 8-18% acrylonitrile-butadiene-styrene, 2-4% glass fiber, 8-14% toughening agent, 7-11% lubricant, 6-9% compatibilizer, 8-14% processing aid and 1-3% flame retardant.

2. The PC material for automotive thin-wall injection molding according to claim 1, characterized in that: The polycarbonate is prepared by either or both of the two processes of phosgene polymerization and transesterification.

3. The PC material for automotive thin-wall injection molding according to claim 1, characterized in that: The toughening agent is composed of a mixture of silicone-based acrylic MBS and butadiene-based MBS.

4. The PC material for automotive thin-wall injection molding according to claim 1, characterized in that: The lubricant is selected from any two or more of stearate, fatty amide, and silicone.

5. The PC material for automotive thin-wall injection molding according to claim 1, characterized in that: The compatibilizer is selected from any two or more of PP grafting, POE grafting, and EPDM grafting.

6. The PC material for automotive thin-wall injection molding according to claim 1, characterized in that: The diameter of the glass fiber is an alkali-free short glass fiber with a diameter of 4-7 μm.

7. The PC material for automotive thin-wall injection molding according to claim 1, characterized in that: The processing aid is selected from any two or more of hindered phenols, thioesters, phosphites, and weathering agents.

8. The PC material for automotive thin-wall injection molding according to claim 1, characterized in that: The flame retardant is selected from any one or two of phosphates and phosphonates.

9. A method for preparing PC material for automotive thin-walled injection molded parts according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1. Material preparation: Prepare sufficient amounts of polycarbonate raw materials by phosgene polymerization and transesterification respectively; S2. Material preparation: The polycarbonate raw materials and acrylonitrile-butadiene-styrene raw materials manufactured by the two processes are ultrasonically cleaned in water at a temperature of 20-40° C. for 4-15 minutes, then rinsed with deionized water, and then dried in a dryer for 2-4 hours at a temperature of 85-95° C.; S3. Ingredients: Weigh various raw materials according to the weight percentage of the formula components of this PC material, namely 27-60% polycarbonate, 8-18% acrylonitrile-butadiene-styrene, 2-4% glass fiber, 8-14% toughening agent, 7-11% lubricant, 6-9% compatibilizer, 8-14% processing aid, and 1-3% flame retardant; S4, raw material mixing: put the various raw materials in S3 into a mixing barrel according to weight percentage and stir and mix them thoroughly at a speed of 200-400 rpm for 10-20 min to obtain a mixed material; S5. Feeding and melting: Add the mixed material into the twin-screw extruder, and control the barrel temperature of the twin-screw extruder at 220-270°C; S6. Finished product preparation: The PC material is extruded through a twin-screw extruder, and is drawn into strips and water-cooled before being drawn into shape. The formed material is then pelletized through a pelletizer to obtain PC material for automotive thin-walled injection molding parts.

Images