Halogen-free flame-retardant PC composite material with high ultrasonic welding strength

Abstract

The application provides a halogen-free flame-retardant PC composite material with high ultrasonic welding strength, characterized by comprising the following components in parts by weight: PC, 77-98 parts; toughening agent, 1-5 parts; flame retardant, 0.2-10 parts; anti-dripping agent, 0.05-2 parts; antioxidant, 0.05-2 parts; lubricant, 0.05-2 parts; toner, 0.05-2 parts.The application has the beneficial effect that the halogen-free flame-retardant PC composite material with high ultrasonic welding strength provided by the application can have good welding strength and flame retardancy without adding welding enhancer and halogen-containing flame retardant, and can be more widely applied in the fields of battery shell, power converter shell, new energy automobile charging gun shell and interior decoration, thereby expanding the application range of the composite material.

Description

[Technical Field]

[0001] This invention relates to the field of composite material technology, and in particular to a halogen-free flame-retardant PC composite material with high ultrasonic welding strength. [Background Technology]

[0002] Polycarbonate (PC) is an engineering plastic with good mechanical properties, toughness, heat resistance, UV resistance, electrical properties, and dimensional stability. PC itself has a UL94 V-2 flame retardant rating and is mainly used in the glass assembly industry, automotive industry, and electronics industry. With the development of the electronics industry, PC materials are increasingly widely used in the manufacturing of electronic devices. Some parts in electronic device housings and other products require welding, and ultrasonic vibration friction welding is widely used for welding PC materials due to its simple equipment and process, ease of operation, and low cost. However, the ultrasonic welding characteristics of PC materials are generally limited. Currently, to improve the welding strength of PC materials, two methods are generally used: one is to add welding reinforcing agents to the PC material, but this method increases costs; the other is to increase welding time, increase ultrasonic frequency, and increase welding area to enhance welding strength, but this method reduces the welding qualification rate, increases costs, and because welding equipment is generally difficult to configure differently for different materials, the welding strength of PC materials may not meet design requirements.

[0003] Therefore, this invention provides a high ultrasonic welding strength halogen-free flame-retardant PC composite material. By appropriately adjusting the composition from the perspective of composite materials, without adding welding reinforcing agents and halogen-containing flame retardants, the composite material has good welding strength and flame retardancy, enabling it to be more widely used in battery casings, power converter casings, new energy vehicle charging gun casings, and interior decorations. [Summary of the Invention]

[0004] The technical problem this invention aims to solve is that current methods for improving the ultrasonic welding strength of PC materials suffer from high costs, low welding pass rates, and welding strength that fails to meet design requirements. This invention provides a halogen-free flame-retardant PC composite material with high ultrasonic welding strength to address these problems.

[0005] The solution to the technical problem of this invention is: a halogen-free flame-retardant PC composite material with high ultrasonic welding strength, comprising the following components in parts by weight:

[0006] PC, 77-98 copies;

[0007] Toughening agent, 1-5 parts;

[0008] Flame retardant, 0.2 to 10 parts;

[0009] Anti-dripping agent, 0.05–2 parts;

[0010] Antioxidant, 0.05–2 parts;

[0011] Lubricant, 0.05 to 2 parts;

[0012] Pigment powder, 0.05 to 2 parts.

[0013] Preferably, the PC is one or more of the following: bisphenol A type PC, polyester type PC, organosilicon copolymer PC, cyclohexane bisphenol A type PC, and high-temperature resistant PC synthesized from bisphenol TMC. The melt flow rate MI of the PC is (3-40) g / 10 min (300℃ / 1.2Kg), the weight average molecular weight is 20,000-50,000, and the molecular weight distribution is 1-2.5.

[0014] Preferably, the toughening agent is one or more of the following: core-shell acrylate-PMMA toughening agents, core-shell acrylate-SAN toughening agents, core-shell silicone-PMMA toughening agents, core-shell silicone-SAN toughening agents, cross-linked methacrylate-methyl methacrylate toughening agents, butadiene-styrene-methyl methacrylate toughening agents, and silicone rubber-methyl methacrylate toughening agents.

[0015] Preferably, the flame retardant is one or more of the following: hypophosphite flame retardants, phosphate ester flame retardants, sulfonate flame retardants, and organosilicon flame retardants.

[0016] Preferably, the hypophosphite-based flame retardant includes vinyl aluminum hypophosphite and vinyl phosphoric acid; the phosphate ester-based flame retardant includes 1,3-phenylene phosphate (2,6-tolyl) tetraester, tetraphenyl bisphenol A diphosphate and its derivatives (BDP), tetraphenyl resorcinol diphosphate and its derivatives (RDP), and triphenyl phosphate (TPP); the sulfonate-based flame retardant includes potassium benzenesulfonylbenzenesulfonate (KSS), potassium perfluorobutyl sulfonate (PPFBS), and sodium 2,4,5-trichlorobenzenesulfonate (STB); and the organosilicon-based flame retardant includes polysiloxane and its derivatives, and cross-linked polydimethylsiloxane (PDMS) and its derivatives.

[0017] Preferably, the anti-dripping agent is a fluorinated PTFE material, including core-shell coated PTFE material and core-shell uncoated PTFE (pure powder) material.

[0018] Preferably, the antioxidant is one or more of hindered phenolic antioxidants, phosphite antioxidants, and thiolated antioxidants.

[0019] Preferably, the hindered phenolic antioxidant includes β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid n-octadecyl alcohol; the phosphite antioxidant includes tris(2,4-di-tert-butylphenyl) phosphite and pentaerythritol diphosphite.

[0020] Preferably, the lubricant is ethylene bis-stearamide.

[0021] Preferably, the color powder is a pigment powder used to change the color of the composite material.

[0022] Preferably, the pigment is carbon black.

[0023] A method for preparing a high ultrasonic welding strength halogen-free flame-retardant PC composite material, characterized in that the components are mixed evenly and then fed into an extruder for extrusion granulation, wherein the extruder is a twin-screw extruder, the processing temperature range of the extruder is set to 280℃~290℃, and the screw speed of the extruder is 400~600RPM.

[0024] The beneficial effects of this invention are that the high ultrasonic welding strength halogen-free flame-retardant PC composite material provided by this invention, without the addition of welding reinforcing agents and halogen-containing flame retardants, enables the composite material to have good ultrasonic welding strength and flame retardancy, and can be more widely used in battery casings, power converter casings, new energy vehicle charging gun casings and interiors, etc., thus expanding the application range of composite materials. [Attached Image Description]

[0025] Figure 1 This is a schematic diagram of the structure of the top cover of the product made by particle injection molding in Examples 1-2 and Comparative Examples 1-2.

[0026] Figure 2 This is a schematic diagram of the structure of the lower cover of the product made by particle injection molding in Examples 1-2 and Comparative Examples 1-2.

Detailed Implementation Methods

[0027] To further illustrate the technical means and effects of the present invention, the following detailed description is provided in conjunction with the embodiments of the present invention and their accompanying drawings.

[0028] This invention provides a high ultrasonic welding strength halogen-free flame-retardant PC composite material, comprising the following components in parts by weight:

[0029] PC, 77-98 copies;

[0030] Toughening agent, 1-5 parts;

[0031] Flame retardant, 0.2 to 10 parts;

[0032] Anti-dripping agent, 0.05–2 parts;

[0033] Antioxidant, 0.05–2 parts;

[0034] Lubricant, 0.05 to 2 parts;

[0035] Pigment powder, 0.05 to 2 parts.

[0036] The PC is one or more of the following: bisphenol A type PC, polyester type PC, organosilicon copolymer PC, cyclohexane bisphenol A type PC, and high-temperature resistant PC synthesized from bisphenol TMC. The melt flow rate MI of the PC is (3-40) g / 10 min (300℃ / 1.2Kg), the weight average molecular weight is 20,000-50,000, and the molecular weight distribution is 1-2.5.

[0037] The toughening agent is one or more of the following: core-shell acrylate-PMMA toughening agents, core-shell acrylate-SAN toughening agents, core-shell silicone-PMMA toughening agents, core-shell silicone-SAN toughening agents, cross-linked methacrylate-methyl methacrylate toughening agents, butadiene-styrene-methyl methacrylate toughening agents, and silicone rubber-methyl methacrylate toughening agents.

[0038] The flame retardant is one or more of the following: hypophosphite flame retardants, phosphate ester flame retardants, sulfonate flame retardants, and organosilicon flame retardants.

[0039] The hypophosphite-based flame retardants include vinyl aluminum hypophosphite and vinyl phosphoric acid; the phosphate ester-based flame retardants include 1,3-phenylene phosphate (2,6-tolyl) tetraester, tetraphenyl bisphenol A diphosphate and its derivatives (BDP), tetraphenyl resorcinol diphosphate and its derivatives (RDP), and triphenyl phosphate (TPP); the sulfonate-based flame retardants include potassium benzenesulfonylbenzenesulfonate (KSS), potassium perfluorobutyl sulfonate (PPFBS), and sodium 2,4,5-trichlorobenzenesulfonate (STB); and the organosilicon-based flame retardants include polysiloxane and its derivatives, and cross-linked polydimethylsiloxane (PDMS) and its derivatives.

[0040] The anti-dripping agent is a fluorinated PTFE material, including core-shell coated PTFE material and core-shell uncoated PTFE (pure powder) material.

[0041] The antioxidant is one or more of hindered phenolic antioxidants, phosphite antioxidants, and thiolated antioxidants.

[0042] The hindered phenolic antioxidants include β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid octadecyl alcohol; the phosphite antioxidants include tris(2,4-di-tert-butylphenyl) phosphite and pentaerythritol diphosphite.

[0043] The lubricant is ethylene bis-stearamide.

[0044] The color powder is a pigment powder used to change the color of the composite material.

[0045] The pigment is carbon black.

[0046] Example 1

[0047] A high ultrasonic welding strength halogen-free flame-retardant PC composite material comprises the following components in parts by weight: 96 parts PC, 2 parts toughening agent, 0.6 parts flame retardant, 0.2 parts anti-dripping agent, 0.3 parts antioxidant, 0.3 parts lubricant, and 0.6 parts colorant.

[0048] The PC is a bisphenol A linear PC synthesized using the phosgene method. The PC has a molecular weight (MI) of 5.3 g / 10 min (300 °C / 1.2 kg), a weight-average molecular weight of 20,000 to 50,000, and a molecular weight distribution of 1 to 2.5.

[0049] The toughening agent is a toughening agent with an MMA copolymer shell and a silicone / acrylic acid core. The Japanese Mitsubishi S-2030 toughening agent is selected, which can significantly improve the impact resistance of resins and engineering plastics, and at the same time has excellent heat aging resistance and hydrolysis resistance.

[0050] The 0.6 parts of flame retardant is a compound of 0.2 parts of sulfonate flame retardant and 0.4 parts of silicone flame retardant. The sulfonate flame retardant is PSS-K type flame retardant from SONY Corporation of Japan, and the silicone flame retardant is KR480 type flame retardant from Shin-Etsu Corporation of Japan. The compound of the two has the advantages of low addition amount and can improve the flame retardant requirements and fire resistance rating of composite materials with a thickness of less than or equal to 1.6 mm.

[0051] The anti-dripping agent is a core-shell non-coated PTFE (pure powder) anti-dripping agent, specifically the FA500H type anti-dripping agent from Daikin Industries, Japan, which has the advantages of low addition amount and significant anti-dripping effect.

[0052] The 0.3 parts antioxidant is a compound of 0.24 parts hindered phenolic antioxidant and 0.06 parts phosphite antioxidant. The hindered phenolic antioxidant is selected from β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid octadecyl alcohol, i.e., antioxidant 1076, and the phosphite antioxidant is selected from tris(2,4-di-tert-butylphenyl) phosphite, i.e., antioxidant 168. The two have a significant synergistic effect and have the advantages of low addition amount and significant antioxidant and anti-yellowing effects.

[0053] The lubricant is ethylene bis-stearamide, which can improve the flowability and processing performance of the composite material.

[0054] The pigment is carbon black, which has the advantages of strong dyeing ability, stable hue, high blackness, and good dispersibility.

[0055] To prepare the high ultrasonic welding strength halogen-free flame-retardant PC composite material, the corresponding weight parts of the components were weighed according to the above proportions, and the components were mixed evenly and then fed into an extruder for extrusion granulation. The extruder was a twin-screw extruder, and the processing temperature range of the extruder was set to 280℃~290℃. The screw speed of the extruder was 400~600RPM.

[0056] Comparative Example 1

[0057] A PC composite material comprises the following components in parts by weight: 96 parts PC, 2 parts toughening agent, 0.6 parts flame retardant, 0.2 parts anti-dripping agent, 0.3 parts antioxidant, 0.3 parts lubricant, and 0.6 parts colored sand.

[0058] The PC is a bisphenol A linear PC synthesized using the phosgene method. The PC has a molecular weight (MI) of 5.3 g / 10 min (300 °C / 1.2 kg), a weight-average molecular weight of 20,000 to 50,000, and a molecular weight distribution of 1 to 2.5.

[0059] The toughening agent is a toughening agent with an MMA copolymer shell and a silicone / acrylic acid core. The Japanese Mitsubishi S-2030 toughening agent is selected, which can significantly improve the impact resistance of resins and engineering plastics, and at the same time has excellent heat aging resistance and hydrolysis resistance.

[0060] The 0.6 parts of flame retardant is a compound of 0.2 parts of sulfonate flame retardant and 0.4 parts of silicone flame retardant. The sulfonate flame retardant is PSS-K type flame retardant from SONY Corporation of Japan, and the silicone flame retardant is KR480 type flame retardant from Shin-Etsu Corporation of Japan. The compound of the two has the advantages of low addition amount and can improve the flame retardant requirements and fire resistance rating of composite materials with a thickness of less than or equal to 1.6 mm.

[0061] The anti-dripping agent is a core-shell non-coated PTFE (pure powder) anti-dripping agent, specifically the FA500H type anti-dripping agent from Daikin Industries, Japan, which has the advantages of low addition amount and significant anti-dripping effect.

[0062] The 0.3 parts antioxidant is a compound of 0.24 parts hindered phenolic antioxidant and 0.06 parts phosphite antioxidant. The hindered phenolic antioxidant is selected from β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid octadecyl alcohol, i.e., antioxidant 1076, and the phosphite antioxidant is selected from tris(2,4-di-tert-butylphenyl) phosphite, i.e., antioxidant 168. The two have a significant synergistic effect and have the advantages of low addition amount and significant antioxidant and anti-yellowing effects.

[0063] The lubricant is ethylene bis-stearamide, which can improve the flowability and processing performance of the composite material.

[0064] The colored sand is black colored sand, specifically the Furis 8086 type black colored sand.

[0065] To prepare the PC composite material, the corresponding weight parts of the components are weighed according to the above proportions, and the components are mixed evenly and then fed into an extruder for extrusion granulation. The extruder is a twin-screw extruder, and the processing temperature range of the extruder is set to 280℃~290℃. The screw speed of the extruder is 400~600RPM.

[0066] Example 2

[0067] A high ultrasonic welding strength halogen-free flame-retardant PC composite material comprises the following components in parts by weight: 96.5 parts PC, 1.5 parts toughening agent, 0.6 parts flame retardant, 0.2 parts anti-dripping agent, 0.3 parts antioxidant, 0.3 parts lubricant, and 0.6 parts colorant.

[0068] The PC is a bisphenol A linear PC synthesized using the phosgene method. The PC has a molecular weight (MI) of 5.3 g / 10 min (300 °C / 1.2 kg), a weight-average molecular weight of 20,000 to 50,000, and a molecular weight distribution of 1 to 2.5.

[0069] The toughening agent is a toughening agent with an MMA copolymer shell and a silicone / acrylic acid core. The Japanese Mitsubishi S-2030 toughening agent is selected, which can significantly improve the impact resistance of resins and engineering plastics, and at the same time has excellent heat aging resistance and hydrolysis resistance.

[0070] The 0.6 parts of flame retardant is a compound of 0.2 parts of sulfonate flame retardant and 0.4 parts of silicone flame retardant. The sulfonate flame retardant is PSS-K type flame retardant from SONY Corporation of Japan, and the silicone flame retardant is KR480 type flame retardant from Shin-Etsu Corporation of Japan. The compound of the two has the advantages of low addition amount and can improve the flame retardant requirements and fire resistance rating of composite materials with a thickness of less than or equal to 1.6 mm.

[0071] The anti-dripping agent is a core-shell non-coated PTFE (pure powder) anti-dripping agent, specifically the FA500H type anti-dripping agent from Daikin Industries, Japan, which has the advantages of low addition amount and significant anti-dripping effect.

[0072] The 0.3 parts antioxidant is a compound of 0.24 parts hindered phenolic antioxidant and 0.06 parts phosphite antioxidant. The hindered phenolic antioxidant is selected from β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid octadecyl alcohol, i.e., antioxidant 1076, and the phosphite antioxidant is selected from tris(2,4-di-tert-butylphenyl) phosphite, i.e., antioxidant 168. The two have a significant synergistic effect and have the advantages of low addition amount and significant antioxidant and anti-yellowing effects.

[0073] The lubricant is ethylene bis-stearamide, which can improve the flowability and processing performance of the composite material.

[0074] The pigment is carbon black, which has the advantages of strong dyeing ability, stable hue, high blackness, and good dispersibility.

[0075] To prepare the high ultrasonic welding strength halogen-free flame-retardant PC composite material, the corresponding weight parts of the components were weighed according to the above proportions, and the components were mixed evenly and then fed into an extruder for extrusion granulation. The extruder was a twin-screw extruder, and the processing temperature range of the extruder was set to 280℃~290℃. The screw speed of the extruder was 400~600RPM.

[0076] Comparative Example 2

[0077] A PC composite material comprises the following components in parts by weight: 96 parts PC, 2 parts toughening agent, 0.6 parts flame retardant, 0.2 parts anti-dripping agent, 0.3 parts antioxidant, 0.3 parts lubricant, and 0.6 parts colorant.

[0078] The 96 PCs include 78 parts of bisphenol A linear PC synthesized using the phosgene method with an MI of 5.3 g / 10 min (300℃ / 1.2 kg), a weight-average molecular weight of 20,000 to 50,000, and a molecular weight distribution of 1 to 2.5, and 18 parts of a compound of bisphenol A linear PC synthesized using the phosgene method with an MI of 57 g / 10 min (300℃ / 1.2 kg), a weight-average molecular weight of 20,000 to 50,000, and a molecular weight distribution of 1 to 2.5.

[0079] The toughening agent is a toughening agent with an MMA copolymer shell and a silicone / acrylic acid core. The Japanese Mitsubishi S-2030 toughening agent is selected, which can significantly improve the impact resistance of resins and engineering plastics, and at the same time has excellent heat aging resistance and hydrolysis resistance.

[0080] The 0.6 parts of flame retardant is a compound of 0.2 parts of sulfonate flame retardant and 0.4 parts of silicone flame retardant. The sulfonate flame retardant is PSS-K type flame retardant from SONY Corporation of Japan, and the silicone flame retardant is KR480 type flame retardant from Shin-Etsu Corporation of Japan. The compound of the two has the advantages of low addition amount and can improve the flame retardant requirements and fire resistance rating of composite materials with a thickness of less than or equal to 1.6 mm.

[0081] The anti-dripping agent is a core-shell non-coated PTFE (pure powder) anti-dripping agent, specifically the FA500H type anti-dripping agent from Daikin Industries, Japan, which has the advantages of low addition amount and significant anti-dripping effect.

[0082] The 0.3 parts antioxidant is a compound of 0.24 parts hindered phenolic antioxidant and 0.06 parts phosphite antioxidant. The hindered phenolic antioxidant is selected from β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid octadecyl alcohol, i.e., antioxidant 1076, and the phosphite antioxidant is selected from tris(2,4-di-tert-butylphenyl) phosphite, i.e., antioxidant 168. The two have a significant synergistic effect and have the advantages of low addition amount and significant antioxidant and anti-yellowing effects.

[0083] The lubricant is ethylene bis-stearamide, which can improve the flowability and processing performance of the composite material.

[0084] The pigment is carbon black.

[0085] To prepare the PC composite material, the corresponding weight parts of the components are weighed according to the above proportions, and the components are mixed evenly and then fed into an extruder for extrusion granulation. The extruder is a twin-screw extruder, and the processing temperature range of the extruder is set to 280℃~290℃. The screw speed of the extruder is 400~600RPM.

[0086] The particles from Example 1, Comparative Example 1, Example 2, and Comparative Example 2 were injection molded into standard test strips on an injection molding machine. The test strips were subjected to relevant physical property tests according to the standard, and the test results were recorded in Table 1.

[0087] The particles from Example 1, Comparative Example 1, Example 2, and Comparative Example 2 were then injection molded at 290°C into an upper cover 10 and a lower cover 11 of the product, respectively. The upper cover 10 is as shown in the attached figure. Figure 1 As shown, the upper cover 10 is provided with a welding part 100 for welding to the lower cover 11. The welding part 100 is a triangular prism with an equilateral triangle cross-section and a side length of 8mm. The lower cover 11 is as shown in the attached figure. Figure 2 As shown, the lower cover 11 has a groove 110 for accommodating the welded part 100. The groove 110 is 1.6 mm wide and 1 mm deep. The upper cover 10 is assembled onto the lower cover 11, and the welded part 100 is completely accommodated in the groove 110. Then, ultrasonic welding equipment is used to weld the joint between the upper cover 10 and the lower cover 11. The welding time is 0.22 s, the welding pressure is 220 N, and the ultrasonic amplitude is 20 kHz. Then, the welded product is subjected to drop test and ultrasonic weld strength test. The test results are recorded in Table 1, where:

[0088] The drop test method is as follows:

[0089] First drop test: With the top cover 10 of the product facing upward and parallel to the horizontal plane, drop it freely from a height of 2m. Check whether there is a crack between the top cover 10 and the bottom cover 11. If there is no crack, the test is qualified; otherwise, it is unqualified.

[0090] Second drop test: With the lower cover 11 of the product facing upward and parallel to the horizontal plane, drop it freely from a height of 2m. Check whether there is a crack between the upper cover 10 and the lower cover 11. If there is no crack, the test is qualified; otherwise, it is unqualified.

[0091] The third drop test: The upper cover 10 and lower cover 11 of the product are placed perpendicular to the horizontal plane and dropped freely from a height of 2m. Check whether there is any crack between the upper cover 10 and the lower cover 11. If there is no crack, the test is qualified; otherwise, it is unqualified.

[0092] The ultrasonic welding strength test process is as follows: The upper cover 10 and the lower cover 11 are clamped by the fixtures of a universal tensile testing machine. The ultrasonic welding strength is expressed by the pull-out force (the maximum pull-out force that pulls the upper cover 10 and the lower cover 11 apart). The test results are shown in Table 1.

[0093] Table 1 Test Results

[0094] MI 300℃ / 1.2kg ISO1133 9 9.4 8.9 12.7 Flame retardant rating UL94 1.6mmV-0 1.6mmV-0 1.6mmV-0 1.6mmV-0 First drop test / qualified Unqualified qualified Unqualified Second drop test / qualified Unqualified qualified Unqualified Third drop test / qualified Unqualified qualified Unqualified Maximum pull-out force (N) / 1945 1852 2385 1670

[0095] The test results in the table above show that this invention, by adding toughening agents, flame retardants, anti-dripping agents, antioxidants, lubricants to PC, replacing conventionally used colored sand with color powder, selecting PC with a suitable flowability index, and adjusting the mass ratio of each component, has achieved the preparation of a halogen-free flame-retardant PC composite material with high ultrasonic welding strength. The resulting composite material has good flame-retardant properties and also has good ultrasonic welding strength (passing the drop test and the maximum pull-out force between the upper cover 10 and the lower cover 11 of the product reaches more than 1900N), thus expanding the application range of the composite material.

[0096] It should be noted that the present invention is not limited to the above embodiments. Any simple modifications, equivalent changes and alterations made by those skilled in the art to the above embodiments based on the technical solutions of the present invention shall fall within the protection scope of the present invention.

Claims

1. A halogen-free flame-retardant PC composite material with high ultrasonic welding strength, characterized in that, Includes the following components in parts by weight: PC, 77-98 copies; Toughening agent, 1-5 parts; Flame retardant, 0.2 to 10 parts; Anti-dripping agent, 0.05–2 parts; Antioxidant, 0.05–2 parts; Lubricant, 0.05 to 2 parts; Pigment powder, 0.05 to 2 parts.

2. The high ultrasonic welding strength halogen-free flame-retardant PC composite material as described in claim 1, characterized in that: The PC is one or more of the following: bisphenol A type PC, polyester type PC, organosilicon copolymer PC, cyclohexane bisphenol A type PC, and high-temperature resistant PC synthesized from bisphenol TMC. The melt flow rate MI of the PC is (3-40) g / 10 min (300℃ / 1.2Kg), the weight average molecular weight is 20,000-50,000, and the molecular weight distribution is 1-2.

5.

3. The high ultrasonic welding strength halogen-free flame-retardant PC composite material as described in claim 1, characterized in that: The toughening agent is one or more of the following: core-shell acrylate-PMMA toughening agents, core-shell acrylate-SAN toughening agents, core-shell silicone-PMMA toughening agents, core-shell silicone-SAN toughening agents, cross-linked methacrylate-methyl methacrylate toughening agents, butadiene-styrene-methyl methacrylate toughening agents, and silicone rubber-methyl methacrylate toughening agents.

4. The high ultrasonic welding strength halogen-free flame-retardant PC composite material as described in claim 1, characterized in that: The flame retardant is one or more of the following: hypophosphite flame retardants, phosphate ester flame retardants, sulfonate flame retardants, and organosilicon flame retardants.

5. The high ultrasonic welding strength halogen-free flame-retardant PC composite material as described in claim 1, characterized in that: The anti-dripping agent is a fluorinated PTFE material, including core-shell coated PTFE material and core-shell uncoated PTFE material.

6. The high ultrasonic welding strength halogen-free flame-retardant PC composite material as described in claim 1, characterized in that: The antioxidant is one or more of hindered phenolic antioxidants, phosphite antioxidants, and thiolated antioxidants.

7. The high ultrasonic welding strength halogen-free flame-retardant PC composite material as described in claim 1, characterized in that: The lubricant is ethylene bis-stearamide.

8. The high ultrasonic welding strength halogen-free flame-retardant PC composite material as described in claim 1, characterized in that: The color powder is a pigment powder used to change the color of the composite material.

9. The high ultrasonic welding strength halogen-free flame-retardant PC composite material as described in claim 8, characterized in that: The pigment is carbon black.

10. A method for preparing a high ultrasonic welding strength halogen-free flame-retardant PC composite material according to any one of claims 1-9, characterized in that: After the components are mixed evenly, they are fed into an extruder for granulation. The extruder is a twin-screw extruder, and the processing temperature range of the extruder is set to 280℃~290℃. The screw speed of the extruder is 400~600RPM.

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