Halogen-free and fluorine-free flame-retardant PC composite material with low-temperature toughness and environmental protection

Abstract

This invention provides a halogen-free and fluorine-free flame-retardant PC composite material that combines low-temperature toughness and environmental friendliness. It is characterized by comprising the following components in parts by weight: PC, 50-99.1 parts; toughening agent, 0.5-10 parts; toughening compatibilizer, 0.2-10 parts; flame retardant, 0.1-10 parts; anti-dripping agent, 0.05-10 parts; antioxidant, 0.05-10 parts; wherein the anti-dripping agent is a fluorine-free anti-dripping agent, and is one or more of the following: silicon-based anti-dripping agent, carbon-based anti-dripping agent, whisker-based anti-dripping agent, and inorganic clay-based anti-dripping agent. The composite material obtained by this invention has both good flame retardancy and low-temperature toughness. The composite material does not contain halogen compounds or fluorine compounds, reducing the risk of secondary pollution during recycling and improving the environmental friendliness 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 and fluorine-free flame-retardant PC composite material that combines low-temperature resistance, toughness, and environmental friendliness. [Background Technology]

[0002] Polycarbonate (PC) is a high-molecular polymer containing carbonate groups in its molecular chain. It possesses excellent mechanical properties, dimensional stability, toughness, heat resistance, and electrical insulation. PC materials are widely used in business communication equipment, automotive interior parts, 3C electronics, home appliances, and other related industries and fields. PC itself has a UL94 V-2 flame retardant rating and drips when exposed to fire. Unmodified PC also suffers from notch sensitivity, stress concentration, and cracking issues, most notably poor low-temperature toughness (the material's notched impact strength at -10℃ is more than 70% of that at room temperature (23℃)). Therefore, in practical production and applications, PC needs to be modified to meet requirements such as toughening, improving molding and processing performance, reducing residual deformation, and enhancing flame retardancy, making it suitable for use in harsh environments such as cold regions. Currently, there is limited research in the industry on PC materials that combine low-temperature toughness and halogen-free, fluorine-free flame retardancy. This is mainly because improving the low-temperature toughness of PC generally uses elastomer-based toughening agents, which significantly reduces flame retardancy, making it difficult to simultaneously satisfy both low-temperature toughness and good flame retardancy in PC materials.

[0003] Currently, the most common method in the 3C electronics industry to improve the flame retardant performance of PCs is to use halogen-free flame retardants and PTFE-containing anti-dripping agents in combination. Among these, perfluorobutyl sulfonate flame retardants (PFBS) are the most effective due to their extremely low addition amount and excellent flame retardant effect. By combining them with other series of flame retardants, they can quickly meet the flame retardant requirements for ultra-thin thicknesses. However, PFBS additives belong to perfluorinated or polyfluoroalkyl substances (PFAS), which have very strong and stable carbon-fluorine bonds. They are extremely stable and can persist in the environment for decades or longer, posing potential hazards and impacts on health and the environment. Composite materials with added PTFE-containing anti-dripping agents will also generate fluorine-containing substances during subsequent use or recycling, causing harm to human health and the ecological environment.

[0004] In view of this, the present invention provides a halogen-free and fluorine-free flame-retardant PC composite material that combines low-temperature toughness and environmental friendliness to solve the above problems. [Summary of the Invention]

[0005] The technical problem this invention aims to solve is that while adding elastomer-based toughening agents is a commonly used method to improve the toughness of PC materials, it significantly reduces flame retardant performance. Using perfluorobutyl sulfonate (PFBS) halogen-free flame retardants and PTFE-containing anti-dripping agents can improve the flame retardant properties of PC materials, the fluorine-containing substances pose potential threats to human health and the environment, preventing PC composite materials from simultaneously possessing low-temperature toughness and halogen-free / fluorine-free flame retardancy. This invention provides a halogen-free / fluorine-free flame-retardant PC composite material that combines low-temperature toughness and environmental friendliness to address these problems.

[0006] The solution to the technical problem of this invention is: a halogen-free and fluorine-free flame-retardant PC composite material that combines low-temperature resistance, toughness, and environmental friendliness, comprising the following components in parts by weight:

[0007] PC, 50–99.1 copies;

[0008] Toughening agent, 0.5–10 parts;

[0009] Toughening compatibilizer, 0.2–10 parts;

[0010] Flame retardant, 0.1 to 10 parts;

[0011] Anti-dripping agent, 0.05–10 parts;

[0012] Antioxidant, 0.05–10 parts;

[0013] The anti-dripping agent is a fluorine-free anti-dripping agent, and the anti-dripping agent is one or more of the following: silicon-based anti-dripping agent, carbon-based anti-dripping agent, whisker-based anti-dripping agent, and inorganic clay-based anti-dripping agent.

[0014] Preferably, the PC is virgin PC or recycled PC (PCR PC).

[0015] 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, or high-temperature resistant PC synthesized from bisphenol TMC. The PC has a melt flow rate MI = (4-70) g / 10 min (300℃ / 1.2 kg), a weight-average molecular weight of 20,000-50,000, and a molecular weight distribution of 1-2.5.

[0016] Preferably, the toughening agent is one or more of the following: unsaturated rubber toughening agent, saturated rubber toughening agent, styrene-based thermoplastic elastomer toughening agent, polyurethane-based thermoplastic elastomer toughening agent, polyolefin-based thermoplastic elastomer toughening agent, polyamide-based thermoplastic elastomer toughening agent, high-rubber powder toughening agent, acrylate copolymer toughening agent, silicone / acrylic composite rubber toughening agent, ethylene-methyl acrylate copolymer, or n-butyl acrylate-glycidyl ester toughening agent.

[0017] Preferably, the toughening compatibilizer comprises one or more of the following: carboxylic acid toughening compatibilizer, cyclic anhydride toughening compatibilizer (MAH), epoxy toughening compatibilizer, oxazoline toughening compatibilizer, imide toughening compatibilizer, isocyanate toughening compatibilizer, and low molecular weight toughening compatibilizer.

[0018] Preferably, the flame retardant is a compound of sulfonate flame retardant and organosilicon flame retardant.

[0019] Preferably, the sulfonate flame retardant includes one or more of potassium benzenesulfonylbenzenesulfonate (KSS), sodium 2,4,5-trichlorobenzenesulfonate (STB), and sodium toluenesulfonate (NATS); the organosilicon flame retardant includes organopolysiloxane flame retardants.

[0020] Preferably, the silicon-based anti-drip agent comprises one or more of silicon nanotubes, wollastonite, and talc; the carbon-based anti-drip agent comprises one or two of single-walled carbon nanotubes and multi-walled carbon nanotubes; the whisker-based anti-drip agent comprises one or two of calcium sulfate whiskers and magnesium sulfate whiskers; and the inorganic clay-based anti-drip agent comprises montmorillonite.

[0021] Preferably, the antioxidant is one or more of hindered phenolic antioxidants, phosphite antioxidants, and thiolated antioxidants.

[0022] A method for preparing a halogen-free and fluorine-free flame-retardant PC composite material that combines low-temperature resistance, toughness, and environmental friendliness is characterized in that the components are mixed evenly and then fed into an extruder for extrusion granulation. The extruder is a twin-screw extruder, the processing temperature range of the extruder is set to 270℃~290℃, and the screw speed of the extruder is 450~550RPM.

[0023] The beneficial effects of this invention are that by adding compounded flame retardants without halogen compounds and fluorine-free anti-dripping agents to PC and combining them with other additives, the resulting composite material achieves a good flame retardancy rating while also possessing good low-temperature toughness. The resulting composite material does not contain halogen compounds or fluorine compounds, which reduces the risk of secondary pollution during recycling and reuse, thus improving the environmental friendliness of the composite material.

Detailed Implementation Methods

[0024] To further illustrate the technical means and effects of the present invention, the following detailed description is provided in conjunction with embodiments of the present invention.

[0025] This invention provides a halogen-free and fluorine-free flame-retardant PC composite material that combines low-temperature resistance, toughness, and environmental friendliness, comprising the following components in parts by weight:

[0026] PC, 50–99.1 copies;

[0027] Toughening agent, 0.5–10 parts;

[0028] Toughening compatibilizer, 0.2–10 parts;

[0029] Flame retardant, 0.1 to 10 parts;

[0030] Anti-dripping agent, 0.05–10 parts;

[0031] Antioxidant, 0.05–10 parts;

[0032] The anti-dripping agent is a fluorine-free anti-dripping agent, and the anti-dripping agent is one or more of the following: silicon-based anti-dripping agent, carbon-based anti-dripping agent, whisker-based anti-dripping agent, and inorganic clay-based anti-dripping agent.

[0033] The PC referred to herein is either virgin PC or recycled PC (PCR PC).

[0034] The PC is one or more of the following: bisphenol A type PC, polyester type PC, organosilicon copolymer PC, cyclohexane bisphenol A type PC or high-temperature resistant PC synthesized from bisphenol TMC. The PC has a melt flow rate MI = (4-70) g / 10 min (300℃ / 1.2 kg), a weight-average molecular weight of 20,000-50,000, and a molecular weight distribution of 1-2.5.

[0035] The toughening agent is one or more of the following: unsaturated rubber toughening agent, saturated rubber toughening agent, styrene thermoplastic elastomer toughening agent, polyurethane thermoplastic elastomer toughening agent, polyolefin thermoplastic elastomer toughening agent, polyamide thermoplastic elastomer toughening agent, high-rubber powder toughening agent, acrylate copolymer toughening agent, silicone / acrylic composite rubber toughening agent, ethylene-methyl acrylate copolymer, or n-butyl acrylate-glycidyl ester toughening agent.

[0036] The unsaturated rubber toughening agent includes one or more of nitrile rubber (NBR), natural rubber (NR), styrene-butadiene rubber (SBR), and butadiene rubber (BR); the saturated rubber toughening agent includes one or more of butyl rubber (IIR), ethylene propylene rubber (EPR), ethylene propylene diene monomer (EPDM), and halogenated butyl rubber; the styrene-based thermoplastic elastomer toughening agent includes methyl methacrylate-butadiene-styrene terpolymer (MBS) and styrene-butadiene-styrene copolymer (SBS). The toughening agent comprises one or more of hydrogenated SBS (SEBS) and styrene-isoprene-styrene (SIS); the polyamide thermoplastic elastomer toughening agent includes TPU; the polyolefin thermoplastic elastomer toughening agent comprises one or more of chlorinated polyethylene (CPE), ethylene-octene copolymer (POE), thermoplastic dynamic vulcanizate (TPV), and ethylene-vinyl acetate copolymer (EVA); the polyamide thermoplastic elastomer toughening agent includes TPAE; and the acrylate copolymer toughening agent includes ACR.

[0037] The toughening compatibilizer includes one or more of the following: carboxylic acid toughening compatibilizer, cyclic anhydride toughening compatibilizer (MAH), epoxy toughening compatibilizer, oxazoline toughening compatibilizer, imide toughening compatibilizer, isocyanate toughening compatibilizer, and low molecular weight toughening compatibilizer.

[0038] The carboxylic acid type toughening compatibilizer includes ethylene-methyl acrylate copolymer (E-MA); the cyclic anhydride type toughening compatibilizer (MAH) includes one or more of p(St-MMA-MAH), styrene-butadiene-styrene copolymer grafted maleic anhydride (SBS-g-MAH), and styrene-ethylene-butyl copolymer grafted maleic anhydride (SEBS-g-MAH); the epoxy type toughening compatibilizer includes glycidyl methacrylate (GMA) and ethylene-methyl acrylate... The compatibilizer comprises one or more of the following: ester-glycidyl methacrylate triblock copolymer (E-MA-GMA) and p(St-An-GMA); oxazoline-type toughening compatibilizer includes oxazoline-grafted PS (RPS); the imide-type toughening compatibilizer includes imide-modified polyacrylate; the isocyanate-type toughening compatibilizer includes m-isopropenyl-2,2-dimethylbenzoyl isocyanate; and the low molecular weight toughening compatibilizer comprises one or more of the following: reactive compatibilizer, reactive monomer, and low molecular weight polymer.

[0039] The flame retardant is a compound of sulfonate flame retardant and organosilicon flame retardant.

[0040] The sulfonate flame retardant includes one or more of potassium benzenesulfonylbenzenesulfonate (KSS), sodium 2,4,5-trichlorobenzenesulfonate (STB), and sodium toluenesulfonate (NATS); the organosilicon flame retardant includes organopolysiloxane flame retardants.

[0041] The silicon-based anti-drip agent comprises one or more of silicon nanotubes, wollastonite, and talc; the carbon-based anti-drip agent comprises one or two of single-walled carbon nanotubes and multi-walled carbon nanotubes; the whisker-based anti-drip agent comprises one or two of calcium sulfate whiskers and magnesium sulfate whiskers; and the inorganic clay-based anti-drip agent comprises montmorillonite.

[0042] The antioxidant is one or more of hindered phenolic antioxidants, phosphite antioxidants, and thiolated antioxidants.

[0043] The hindered phenolic antioxidant includes octadecyl acrylate (β-3,5-di-tert-butyl-4-hydroxyphenyl) acrylate; the phosphite antioxidant includes one or a combination of tris(2,4-di-tert-butylphenyl) phosphite and pentaerythritol diphosphite; and the thiolated antioxidant includes one or a combination of lauryl thiodipropionate (DLTDP) and octadecyl thiodipropionate (DSTDP).

[0044] Example 1

[0045] A halogen-free and fluorine-free flame-retardant PC composite material that combines low-temperature toughness and environmental friendliness comprises the following components in parts by weight: 94.7 parts PC, 2 parts toughening agent, 1 part toughening compatibilizer, 1 part flame retardant, 1 part fluorine-free anti-dripping agent, and 0.3 parts antioxidant.

[0046] Of these, the 94.7 PC samples were all PCR PCs, specifically a mixture of 22 MITEK 10050 PCR PCs and 72.7 MITEK 20060 PCR PCs. The MITEK 10050 PCR PC had a melt flow rate (MI) of 66.2 g / 10 min (300℃ / 1.2 kg), a weight-average molecular weight of 25,000–30,000, and a molecular weight distribution of 1.5–2.0. The MITEK 20060 PCR PC had a melt flow rate (MI) of 5.5 g / 10 min (300℃ / 1.2 kg), a weight-average molecular weight of 47,000–50,000, and a molecular weight distribution of 1.5–2.0.

[0047] The toughening agent is a styrene-based thermoplastic elastomer, specifically a methyl methacrylate-butadiene-styrene terpolymer (MBS), which has a core-shell structure with a core of silicon / acrylic acid and a shell of methyl methacrylate-butadiene-styrene terpolymer. It can significantly improve the impact resistance of resins and engineering plastics, and also has excellent low-temperature impact resistance and hydrolysis resistance.

[0048] The toughening compatibilizer is a cyclic anhydride type toughening compatibilizer, specifically a styrene-ethylene-butyl copolymer grafted with maleic anhydride (SEBS-g-MAH), wherein the mass ratio of styrene to ethylene to butene is 20:80. It can be used to modify engineering plastics, has good compatibility with engineering plastics, and has good adhesion to plastic and metal substrates. It can be used as an adhesive or compatibilizer.

[0049] The 1 part flame retardant is a compound of 0.6 parts sulfonate flame retardant and 0.4 parts organosilicon flame retardant. The sulfonate flame retardant is potassium benzenesulfonylbenzenesulfonate (KSS), and the organosilicon flame retardant is an organopolysiloxane flame retardant, specifically the SX12-B type powder flame retardant produced by Shin-Etsu Chemical Co., Ltd. of Japan.

[0050] The fluorine-free anti-drip agent is a silicon-based anti-drip agent, specifically a surface-modified silicon nanowire, using the S890 type anti-drip agent produced by Dongguan Sanhe Chemical.

[0051] The 0.3 parts of antioxidant are a combination of 0.24 parts of hindered phenolic antioxidant and 0.06 parts of phosphite antioxidant. The 0.24 parts of hindered phenolic antioxidant are selected from (β-3,5-di-tert-butyl-4-hydroxyphenyl) octadecyl acrylate, i.e., antioxidant 1076, and the 0.06 parts of phosphite antioxidant are selected from tris(2,4-di-tert-butylphenyl) phosphite, i.e., antioxidant 168.

[0052] To prepare this halogen-free and fluorine-free flame-retardant PC composite material that combines low-temperature resistance, toughness, and environmental friendliness, 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. The mixture of the components is sheared, mixed, and conveyed by the extruder screw, and then fully melted and compounded. It is then extruded through the die head, drawn into strips, cooled, and pelletized to finally obtain the finished particles. The extruder is a twin-screw extruder, the processing temperature range of the extruder is set to 270℃~290℃, and the screw speed of the extruder is 450~550RPM.

[0053] Example 2

[0054] A halogen-free and fluorine-free flame-retardant PC composite material that combines low-temperature toughness and environmental friendliness comprises the following components in parts by weight: 94.2 parts PC, 2 parts toughening agent, 1 part toughening compatibilizer, 1 part flame retardant, 1.5 parts fluorine-free anti-dripping agent, and 0.3 parts antioxidant.

[0055] Of these, the 94.2 PC samples were all PCR PCs, specifically a mixture of 22 MITEK 10050 PCR PCs and 72.2 MITEK 20060 PCR PCs. The MITEK 10050 PCR PC had a melt flow rate (MI) of 66.2 g / 10 min (300℃ / 1.2 kg), a weight-average molecular weight of 25,000–30,000, and a molecular weight distribution of 1.5–2.0. The MITEK 20060 PCR PC had a melt flow rate (MI) of 5.5 g / 10 min (300℃ / 1.2 kg), a weight-average molecular weight of 47,000–50,000, and a molecular weight distribution of 1.5–2.0.

[0056] The toughening agent is a styrene-based thermoplastic elastomer, specifically a methyl methacrylate-butadiene-styrene terpolymer (MBS), which has a core-shell structure with a core of silicon / acrylic acid and a shell of methyl methacrylate-butadiene-styrene terpolymer. It can significantly improve the impact resistance of resins and engineering plastics, and also has excellent low-temperature impact resistance and hydrolysis resistance.

[0057] The toughening compatibilizer is a cyclic anhydride type toughening compatibilizer, specifically a styrene-ethylene-butyl copolymer grafted with maleic anhydride (SEBS-g-MAH), wherein the mass ratio of styrene to ethylene to butene is 20:80. It can be used to modify engineering plastics, has good compatibility with engineering plastics, and has good adhesion to plastic and metal substrates. It can be used as an adhesive or compatibilizer.

[0058] The 1 part flame retardant is a compound of 0.6 parts sulfonate flame retardant and 0.4 parts organosilicon flame retardant. The sulfonate flame retardant is potassium benzenesulfonylbenzenesulfonate (KSS), and the organosilicon flame retardant is an organopolysiloxane flame retardant, specifically the SX12-B type powder flame retardant produced by Shin-Etsu Chemical Co., Ltd. of Japan.

[0059] The fluorine-free anti-drip agent is a silicon-based anti-drip agent, specifically a surface-modified silicon nanowire, using the S890 type anti-drip agent produced by Dongguan Sanhe Chemical.

[0060] The 0.3 parts of antioxidant are a combination of 0.24 parts of hindered phenolic antioxidant and 0.06 parts of phosphite antioxidant. The 0.24 parts of hindered phenolic antioxidant are selected from (β-3,5-di-tert-butyl-4-hydroxyphenyl) octadecyl acrylate, i.e., antioxidant 1076, and the 0.06 parts of phosphite antioxidant are selected from tris(2,4-di-tert-butylphenyl) phosphite, i.e., antioxidant 168.

[0061] To prepare this halogen-free and fluorine-free flame-retardant PC composite material that combines low-temperature resistance, toughness, and environmental friendliness, 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. The mixture of the components is sheared, mixed, and conveyed by the extruder screw, and then fully melted and compounded. It is then extruded through the die head, drawn into strips, cooled, and pelletized to finally obtain the finished particles. The extruder is a twin-screw extruder, the processing temperature range of the extruder is set to 270℃~290℃, and the screw speed of the extruder is 450~550RPM.

[0062] Comparative Example 1

[0063] A PC composite material comprises the following components in parts by weight: 93.2 parts PC, 1.5 parts toughening agent, 1 part toughening compatibilizer, 4 parts flame retardant, and 0.3 parts antioxidant.

[0064] Of these, the 93.2 PC samples were all PCR PCs, specifically a mixture of 22 MITEK 10050 PCR PCs and 71.2 MITEK 20060 PCR PCs. The MITEK 10050 PCR PC had a melt flow rate (MI) of 66.2 g / 10 min (300℃ / 1.2 kg), a weight-average molecular weight of 25,000–30,000, and a molecular weight distribution of 1.5–2.0. The MITEK 20060 PCR PC had a melt flow rate (MI) of 5.5 g / 10 min (300℃ / 1.2 kg), a weight-average molecular weight of 47,000–50,000, and a molecular weight distribution of 1.5–2.0.

[0065] The toughening agent is a styrene-based thermoplastic elastomer, specifically a methyl methacrylate-butadiene-styrene terpolymer (MBS).

[0066] The toughening compatibilizer is a cyclic anhydride type toughening compatibilizer, specifically a styrene-ethylene-butyl copolymer grafted with maleic anhydride (SEBS-g-MAH), wherein the mass ratio of styrene to ethylene-butene is 20:80.

[0067] The four parts of flame retardant are a blend of 0.6 parts of sulfonate flame retardant and 3.4 parts of organosilicon flame retardant. The sulfonate flame retardant is potassium benzenesulfonylbenzenesulfonate (KSS). The 3.4 parts of organosilicon flame retardant are a blend of 0.4 parts of organopolysiloxane flame retardant and 3 parts of organosiloxane flame retardant. The organopolysiloxane flame retardant is SX12-B type powder flame retardant produced by Shin-Etsu Chemical Co., Ltd. of Japan. The organosiloxane flame retardant is 40-001 type liquid flame retardant produced by Dow Corning.

[0068] The 0.3 parts of antioxidant are a combination of 0.24 parts of hindered phenolic antioxidant and 0.06 parts of phosphite antioxidant. The 0.24 parts of hindered phenolic antioxidant are selected from (β-3,5-di-tert-butyl-4-hydroxyphenyl) octadecyl acrylate, i.e., antioxidant 1076, and the 0.06 parts of phosphite antioxidant are selected from tris(2,4-di-tert-butylphenyl) phosphite, i.e., antioxidant 168.

[0069] 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. After the mixture of the components is sheared, mixed and conveyed by the extruder screw, it is fully melted and compounded. Then it is extruded through the die head, drawn into strips, cooled and pelletized to finally obtain finished particles. The extruder is a twin-screw extruder, the processing temperature range of the extruder is set to 270℃~290℃, and the screw speed of the extruder is 450~550RPM.

[0070] Comparative Example 2

[0071] A PC composite material comprises the following components in parts by weight: 92.7 parts PC, 2 parts toughening agent, 1 part toughening compatibilizer, 4 parts flame retardant, and 0.3 parts antioxidant.

[0072] Of these, the 92.7 PC samples were all PCR PCs, specifically a mixture of 22 MITEK 10050 PCR PCs and 70.7 MITEK 20060 PCR PCs. The MITEK 10050 PCR PC had a melt flow rate (MI) of 66.2 g / 10 min (300℃ / 1.2 kg), a weight-average molecular weight of 25,000–30,000, and a molecular weight distribution of 1.5–2.0. The MITEK 20060 PCR PC had a melt flow rate (MI) of 5.5 g / 10 min (300℃ / 1.2 kg), a weight-average molecular weight of 47,000–50,000, and a molecular weight distribution of 1.5–2.0.

[0073] The toughening agent is a styrene-based thermoplastic elastomer, specifically a methyl methacrylate-butadiene-styrene terpolymer (MBS).

[0074] The toughening compatibilizer is a cyclic anhydride type toughening compatibilizer, specifically a styrene-ethylene-butyl copolymer grafted with maleic anhydride (SEBS-g-MAH), wherein the mass ratio of styrene to ethylene-butene is 20:80.

[0075] The four parts of flame retardant are a blend of 0.6 parts of sulfonate flame retardant and 3.4 parts of organosilicon flame retardant. The sulfonate flame retardant is potassium benzenesulfonylbenzenesulfonate (KSS). The 3.4 parts of organosilicon flame retardant are a blend of 0.4 parts of organopolysiloxane flame retardant and 3 parts of organosiloxane flame retardant. The organopolysiloxane flame retardant is SX12-B type powder flame retardant produced by Shin-Etsu Chemical Co., Ltd. of Japan. The organosiloxane flame retardant is 40-001 type liquid flame retardant produced by Dow Corning.

[0076] The 0.3 parts of antioxidant are a combination of 0.24 parts of hindered phenolic antioxidant and 0.06 parts of phosphite antioxidant. The 0.24 parts of hindered phenolic antioxidant are selected from (β-3,5-di-tert-butyl-4-hydroxyphenyl) octadecyl acrylate, i.e., antioxidant 1076, and the 0.06 parts of phosphite antioxidant are selected from tris(2,4-di-tert-butylphenyl) phosphite, i.e., antioxidant 168.

[0077] 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. After the mixture of the components is sheared, mixed and conveyed by the extruder screw, it is fully melted and compounded. Then it is extruded through the die head, drawn into strips, cooled and pelletized to finally obtain finished particles. The extruder is a twin-screw extruder, the processing temperature range of the extruder is set to 270℃~290℃, and the screw speed of the extruder is 450~550RPM.

[0078] Comparative Example 3

[0079] A PC composite material comprises the following components in parts by weight: 95.7 parts PC, 2 parts toughening agent, 1 part toughening compatibilizer, 1 part flame retardant, and 0.3 parts antioxidant.

[0080] Of these, the 95.7 PC samples were all PCR PCs, specifically a mixture of 22 MITEK 10050 PCR PCs and 73.7 MITEK 20060 PCR PCs. The MITEK 10050 PCR PC had a melt flow rate (MI) of 66.2 g / 10 min (300℃ / 1.2 kg), a weight-average molecular weight of 25,000–30,000, and a molecular weight distribution of 1.5–2.0. The MITEK 20060 PCR PC had a melt flow rate (MI) of 5.5 g / 10 min (300℃ / 1.2 kg), a weight-average molecular weight of 47,000–50,000, and a molecular weight distribution of 1.5–2.0.

[0081] The toughening agent is a styrene-based thermoplastic elastomer, specifically a methyl methacrylate-butadiene-styrene terpolymer (MBS).

[0082] The toughening compatibilizer is a cyclic anhydride type toughening compatibilizer, specifically a styrene-ethylene-butyl copolymer grafted with maleic anhydride (SEBS-g-MAH), wherein the mass ratio of styrene to ethylene-butene is 20:80.

[0083] The 1 part flame retardant is a compound of 0.6 parts sulfonate flame retardant and 0.4 parts organosilicon flame retardant. The sulfonate flame retardant is potassium benzenesulfonylbenzenesulfonate (KSS), and the 0.4 parts organosilicon flame retardant is an organopolysiloxane flame retardant, specifically the SX12-B type powder flame retardant manufactured by Shin-Etsu Chemical Co., Ltd. of Japan.

[0084] The 0.3 parts of antioxidant are a combination of 0.24 parts of hindered phenolic antioxidant and 0.06 parts of phosphite antioxidant. The 0.24 parts of hindered phenolic antioxidant are selected from (β-3,5-di-tert-butyl-4-hydroxyphenyl) octadecyl acrylate, i.e., antioxidant 1076, and the 0.06 parts of phosphite antioxidant are selected from tris(2,4-di-tert-butylphenyl) phosphite, i.e., antioxidant 168.

[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. After the mixture of the components is sheared, mixed and conveyed by the extruder screw, it is fully melted and compounded. Then it is extruded through the die head, drawn into strips, cooled and pelletized to finally obtain finished particles. The extruder is a twin-screw extruder, the processing temperature range of the extruder is set to 270℃~290℃, and the screw speed of the extruder is 450~550RPM.

[0086] Comparative Example 4

[0087] A PC composite material comprises the following components in parts by weight: 95.5 parts PC, 2 parts toughening agent, 1 part toughening compatibilizer, 1 part flame retardant, 0.2 parts fluorine-containing anti-dripping agent, and 0.3 parts antioxidant.

[0088] Of these, the 95.5 PC samples were all PCR PCs, specifically a mixture of 22 MITEK 10050 PCR PCs and 73.5 MITEK 20060 PCR PCs. The MITEK 10050 PCR PC had a melt flow rate (MI) of 66.2 g / 10 min (300℃ / 1.2 kg), a weight-average molecular weight of 25,000–30,000, and a molecular weight distribution of 1.5–2.0. The MITEK 20060 PCR PC had a melt flow rate (MI) of 5.5 g / 10 min (300℃ / 1.2 kg), a weight-average molecular weight of 47,000–50,000, and a molecular weight distribution of 1.5–2.0.

[0089] The toughening agent is a styrene-based thermoplastic elastomer, specifically a methyl methacrylate-butadiene-styrene terpolymer (MBS).

[0090] The toughening compatibilizer is a cyclic anhydride type toughening compatibilizer, specifically a styrene-ethylene-butyl copolymer grafted with maleic anhydride (SEBS-g-MAH), wherein the mass ratio of styrene to ethylene-butene is 20:80.

[0091] The 1 part flame retardant is a compound of 0.6 parts sulfonate flame retardant and 0.4 parts organosilicon flame retardant. The sulfonate flame retardant is potassium benzenesulfonylbenzenesulfonate (KSS), and the 0.4 parts organosilicon flame retardant is an organopolysiloxane flame retardant, specifically the SX12-B type powder flame retardant manufactured by Shin-Etsu Chemical Co., Ltd. of Japan.

[0092] The fluorinated anti-dripping agent is a fluorinated, non-coated polytetrafluoroethylene (PTFE) pure powder material with a PTFE content of 100%.

[0093] The 0.3 parts of antioxidant are a combination of 0.24 parts of hindered phenolic antioxidant and 0.06 parts of phosphite antioxidant. The 0.24 parts of hindered phenolic antioxidant are selected from (β-3,5-di-tert-butyl-4-hydroxyphenyl) octadecyl acrylate, i.e., antioxidant 1076, and the 0.06 parts of phosphite antioxidant are selected from tris(2,4-di-tert-butylphenyl) phosphite, i.e., antioxidant 168.

[0094] 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. After the mixture of the components is sheared, mixed and conveyed by the extruder screw, it is fully melted and compounded. Then it is extruded through the die head, drawn into strips, cooled and pelletized to finally obtain finished particles. The extruder is a twin-screw extruder, the processing temperature range of the extruder is set to 270℃~290℃, and the screw speed of the extruder is 450~550RPM.

[0095] The particles from Examples 1-2 and Comparative Examples 1-4 were injection molded into standard test specimens on an injection molding machine. The test specimens were then subjected to relevant physical property tests according to the standard. The test results are shown in Table 1.

[0096] Table 1 Test Results

[0097]

[0098]

[0099] The test results above show that this invention achieves the preparation of a halogen-free and fluorine-free flame-retardant PC composite material that combines low-temperature toughness and environmental friendliness. By adding compounded flame retardants without halogen compounds and fluorine-free anti-dripping agents to PC and combining them with other additives, the resulting composite material achieves a good flame retardancy rating while also possessing good low-temperature toughness (the notched impact strength of the material at -10℃ can maintain more than 70% of that at room temperature (23℃)). The resulting composite material does not contain halogen compounds or fluorine compounds, which can reduce the risk of secondary pollution when recycled and reused, thus improving the environmental friendliness of the composite material.

[0100] 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 and fluorine-free flame-retardant PC composite material that combines low-temperature resistance, toughness, and environmental friendliness, characterized in that, Includes the following components in parts by weight: PC, 50–99.1 copies; Toughening agent, 0.5–10 parts; Toughening compatibilizer, 0.2–10 parts; Flame retardant, 0.1 to 10 parts; Anti-dripping agent, 0.05–10 parts; Antioxidant, 0.05–10 parts; The anti-drip agent is a fluorine-free anti-drip agent, and the anti-drip agent is one or more of the following: silicon-based anti-drip agent, carbon-based anti-drip agent, whisker-based anti-drip agent, and inorganic clay-based anti-drip agent.

2. The halogen-free and fluorine-free flame-retardant PC composite material with low-temperature resistance, toughness, and environmental friendliness as described in claim 1, characterized in that: The PC is either virgin PC or recycled PC.

3. The halogen-free and fluorine-free flame-retardant PC composite material with low-temperature resistance, toughness, and environmental friendliness 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 or high temperature resistant PC synthesized from bisphenol TMC. The melt flow rate MI of the PC is (4-70) g / 10 min (300℃ / 1.2 kg), the weight average molecular weight is 20,000-50,000, and the molecular weight distribution is 1-2.

5.

4. The halogen-free and fluorine-free flame-retardant PC composite material with low-temperature resistance, toughness, and environmental friendliness as described in claim 1, characterized in that: The toughening agent is one or more of the following: unsaturated rubber toughening agents, saturated rubber toughening agents, styrene-based thermoplastic elastomer toughening agents, polyurethane-based thermoplastic elastomer toughening agents, polyolefin-based thermoplastic elastomer toughening agents, polyamide-based thermoplastic elastomer toughening agents, high-rubber powder toughening agents, acrylate copolymer toughening agents, silicone / acrylic composite rubber toughening agents, ethylene-methyl acrylate copolymers, or n-butyl acrylate-glycidyl ester toughening agents.

5. The halogen-free and fluorine-free flame-retardant PC composite material with low-temperature resistance, toughness, and environmental friendliness as described in claim 1, characterized in that: The toughening compatibilizer includes one or more of the following: carboxylic acid toughening compatibilizer, cyclic anhydride toughening compatibilizer, epoxy toughening compatibilizer, oxazoline toughening compatibilizer, imide toughening compatibilizer, isocyanate toughening compatibilizer, and low molecular weight toughening compatibilizer.

6. The halogen-free and fluorine-free flame-retardant PC composite material with low-temperature resistance, toughness, and environmental friendliness as described in claim 1, characterized in that: The flame retardant is a compound of sulfonate flame retardant and organosilicon flame retardant.

7. The halogen-free and fluorine-free flame-retardant PC composite material with low-temperature resistance, toughness, and environmental friendliness as described in claim 6, characterized in that: The sulfonate flame retardant includes one or more of potassium benzenesulfonylbenzenesulfonate, sodium 2,4,5-trichlorobenzenesulfonate, and sodium toluenesulfonate; the organosilicon flame retardant includes organopolysiloxane flame retardants.

8. The halogen-free and fluorine-free flame-retardant PC composite material with low-temperature resistance, toughness, and environmental friendliness as described in claim 1, characterized in that: The silicon-based anti-drip agent comprises one or more of silicon nanotubes, wollastonite, and talc; the carbon-based anti-drip agent comprises one or two of single-walled carbon nanotubes and multi-walled carbon nanotubes; the whisker-based anti-drip agent comprises one or two of calcium sulfate whiskers and magnesium sulfate whiskers; and the inorganic clay-based anti-drip agent comprises montmorillonite.

9. The halogen-free and fluorine-free flame-retardant PC composite material with low-temperature resistance, toughness, and environmental friendliness as described in claim 1, characterized in that: The antioxidant is one or more of hindered phenolic antioxidants, phosphite antioxidants, and thio-antioxidants.

10. A method for preparing a halogen-free and fluorine-free flame-retardant PC composite material with low-temperature resistance, toughness, and environmental friendliness as described in 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 270℃~290℃. The screw speed of the extruder is 450~550RPM.

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