Halogen-free flame-retardant PC-based alloy material and preparation method thereof

Abstract

The invention discloses a halogen-free flame-retardant PC-based alloy material and a preparation method thereof, and relates to the technical field of high polymer materials. Comprising the following raw materials in parts by weight: 65 to 75 parts of bisphenol A polycarbonate, 25 to 35 parts of a functional polymer, 10 to 15 parts of hyperbranched polysiloxane containing a phosphaphenanthrene structure, 3 to 5 parts of a coupling agent, 25 to 35 parts of a filler, 0.3 to 0.5 part of an antioxidant, 0.3 to 0.8 part of a lubricant, 0.5 to 1 part of a catalyst A, 0.8 to 1.2 parts of 2, 7-anthraquinone disulfonic acid, 1 to 2 parts of piperazine-N, N '-bis (2-hydroxypropane sulfonic acid) and 1 to 4 parts of a compatilizer. The material is remarkable in flame retardant effect, good in mechanical property, environmental protection property and impact toughness, excellent in aging resistance and long in service life.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer materials, and in particular to a halogen-free flame-retardant PC-based alloy material and a preparation method thereof. Background Art

[0002] Polycarbonate (PC) is a high-performance thermoplastic engineering plastic with advantages such as high transparency, high strength, good dimensional stability, and electrical insulation. It is widely used in electronics, automobiles, construction, and other fields. However, unmodified PC suffers from insufficient processing fluidity, poor impact toughness, flame retardancy, mechanical properties, and weather resistance. It is precisely in this context that PC-based alloy materials have emerged, attracting widespread attention within the industry.

[0003] PC-based alloy materials are a new type of high-performance, functional, and specialized material obtained by combining polycarbonate (PC) with other polymer materials through physical blending or chemical grafting. Because it combines the advantages of polycarbonate and other polymer materials, this type of material has excellent overall performance. However, due to the compatibility issues between polycarbonate (PC) and other polymer materials, existing PC-based alloy materials generally have defects such as insufficient performance stability, limited mechanical properties, and short service life. In addition, PC-based alloy materials on the market also have more or less technical problems such as insufficient flame retardancy, poor environmental performance, insufficient impact toughness and aging resistance, and short service life.

[0004] To address these issues, Chinese invention patent publication CN109575561B discloses a low-smoke-density, halogen-free, flame-retardant PC / PBT alloy material and its preparation method. The alloy material is composed of the following raw materials by weight: 45-70 parts PC, 10-25 parts PBT, 6-14 parts halogen-free flame retardant, 2-10 parts ultrafine zinc borate, 2-10 parts dimethyl silicone oil, 0.1-2 parts hydrolysis stabilizer, 0.1-2 parts transesterification inhibitor, 2-10 parts toughening agent, and 0.1-1 part lubricant. The invention utilizes zinc borate and dimethyl silicone oil to synergistically suppress smoke, significantly reducing the smoke density of the PC / PBT alloy material. This low-smoke-density, halogen-free, flame-retardant PC / PBT alloy material exhibits excellent flame retardancy and thermal stability, high strength, and good machinability. The process conditions involved are also easily controllable, providing the processing stability required for large-scale production and making it suitable for industrial production. However, the material's aging resistance and impact toughness still need to be further improved.

[0005] It can be seen that the development of a halogen-free flame retardant PC-based alloy material with significant flame retardant effect, good mechanical properties, environmental protection performance and impact toughness, excellent aging resistance and long service life and its preparation method meet market demand, have broad market value and application prospects, and are of great significance to promoting the development of the PC-based alloy material field. Summary of the Invention

[0006] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a halogen-free flame-retardant PC-based alloy material having significant flame retardant effect, good mechanical properties, environmental performance and impact toughness, excellent aging resistance and long service life, and a preparation method thereof.

[0007] To achieve the above-mentioned object, the technical solution adopted by the present invention is: a halogen-free flame-retardant PC-based alloy material, comprising the following raw materials in parts by weight: 65-75 parts of bisphenol A polycarbonate, 25-35 parts of a functional polymer, 10-15 parts of a hyperbranched polysiloxane containing a phosphaphenanthrene structure, 3-5 parts of a coupling agent, 25-35 parts of a filler, 0.3-0.5 parts of an antioxidant, 0.3-0.8 parts of a lubricant, 0.5-1 parts of a catalyst A, 0.8-1.2 parts of 2,7-anthraquinone disulfonic acid, 1-2 parts of piperazine-N,N'-bis(2-hydroxypropanesulfonic acid), and 1-4 parts of a compatibilizer; the functional polymer comprises structural units introduced by the following monomers: N-[(4-methyl-1H-benzotriazol-1-yl)methyl]diethanolamine, 4,6-hydroxy-2-cyanobenzothiazole, and 4,4-diisocyanate dicyclohexylmethane.

[0008] Preferably, the bisphenol A polycarbonate is Covestro 2456 polycarbonate.

[0009] Preferably, the preparation method of the functional polymer comprises the following steps: mixing N-[(4-methyl-1H-benzotriazole-1-yl)methyl]diethanolamine, 4,6-hydroxy-2-cyanobenzothiazole, 4,4-diisocyanate dicyclohexylmethane, catalyst B, and a high-boiling point solvent, stirring and reacting at 80-90°C in an inert gas atmosphere for 1-3 hours, then heating to 100-120°C and continuing to stir and react for 8-10 hours, then rotary evaporating to remove the solvent, washing with ether 3-6 times, and then rotary evaporating to remove residual ether to obtain a functional polymer.

[0010] Preferably, the molar ratio of N-[(4-methyl-1H-benzotriazole-1-yl)methyl]diethanolamine, 4,6-hydroxy-2-cyanobenzothiazole, 4,4-diisocyanate dicyclohexylmethane, catalyst B, and high boiling point solvent is 0.7:0.3:1:(0.8-1.2):(10-15).

[0011] Preferably, the catalyst B is at least one of dibutyltin dilaurate and stannous octoate; the high boiling point solvent is at least one of dimethyl sulfoxide, N,N-dimethylformamide, and N,N-dimethylacetamide; and the inert gas is any one of nitrogen, helium, neon, and argon.

[0012] Preferably, there is no special requirement for the source of the hyperbranched polysiloxane containing a phosphaphenanthrene structure. In one embodiment of the present invention, the hyperbranched polysiloxane containing a phosphaphenanthrene structure is prepared according to the method of Example 1 of the Chinese invention patent with authorization publication number CN102432884B.

[0013] Preferably, the coupling agent is at least one of silane coupling agent KH550, silane coupling agent KH560, and silane coupling agent KH570.

[0014] Preferably, the filler is a mixture of aluminum hydroxide flame retardant VK-LA50 and nano-boron fiber in a mass ratio of (0.8-1.2):1.

[0015] Preferably, the average diameter of the nano-boron fiber is 300-500 nm, and the aspect ratio is (15-25):1.

[0016] Preferably, the antioxidant is at least one of antioxidant 1010, antioxidant 168, and antioxidant 1076.

[0017] Preferably, the lubricant is at least one of pentaerythritol stearate, zinc stearate, and ethylene bisstearamide.

[0018] Preferably, the catalyst A is a mixture of phosphorus pentoxide and polyphosphoric acid in a mass ratio of (1-2):1.

[0019] Preferably, the compatibilizer is maleic anhydride grafted polypropylene, selected from MAH-g-PP with the brand name EXXELOR PO1020 provided by Exxon in the United States.

[0020] Another object of the present invention is to provide a method for preparing the halogen-free flame-retardant PC-based alloy material, comprising the following steps: uniformly mixing the raw materials by weight to obtain a mixture, placing the mixture into a hot pressing mold, preheating the mixture at 80-100°C for 5-10 minutes, and then hot pressing at 175-185°C and 10-20 MPa for 15-25 minutes; subsequently heating the mixture to 230-250°C at a heating rate of 5-10°C / min, keeping the temperature for 3-5 minutes, and then heating the mixture to 280-300°C at a heating rate of 15-20°C / min, keeping the temperature for 1-3 minutes, and maintaining the pressure during the heating process; after the gradient heating is completed, allowing the mold to cool naturally while maintaining the pressure, releasing the pressure when the temperature drops to 60-80°C, and then continuing to cool to room temperature to obtain the halogen-free flame-retardant PC-based alloy material.

[0021] Due to the application of the above technical solution, the present invention has the following beneficial effects:

[0022] (1) The preparation method of the halogen-free flame-retardant PC-based alloy material disclosed in the present invention has a simple preparation process, high efficiency, stable performance of the prepared product, is suitable for large-scale production, does not require special equipment, requires little capital investment, and has high promotion and application value; the use of a hot pressing molding gradient heating method can effectively improve product quality and stability, thereby improving product performance.

[0023] (2) The halogen-free flame-retardant PC-based alloy material disclosed in the present invention is made of the following raw materials in parts by weight: 65-75 parts of bisphenol A polycarbonate, 25-35 parts of functional polymer, 10-15 parts of hyperbranched polysiloxane containing phosphorus-containing phenanthrene structure, 3-5 parts of coupling agent, 25-35 parts of filler, 0.3-0.5 parts of antioxidant, 0.3-0.8 parts of lubricant, catalyst A The functional polymer comprises 0.5-1 parts of benzotriazole, 0.8-1.2 parts of 2,7-anthraquinone disulfonic acid, 1-2 parts of piperazine-N,N'-bis(2-hydroxypropanesulfonic acid), and 1-4 parts of a compatibilizer. Through the interaction and synergy of these raw materials, the resulting alloy material exhibits significant flame retardancy, excellent mechanical and mechanical properties, environmental performance, impact toughness, superior aging resistance, and a long service life. The functional polymer includes structural units introduced from the following monomers: N-[(4-methyl-1H-benzotriazol-1-yl)methyl]diethanolamine, 4,6-hydroxy-2-cyanobenzothiazole, and 4,4-diisocyanate dicyclohexylmethane. The simultaneous introduction of benzotriazole, cyanobenzothiazole, polyurethane, and dicyclohexylmethane structures into the functional polymer molecular chain enhances compatibility with other raw materials through multiple interactions, including electronic, steric, and conjugative effects, resulting in superior flame retardancy, mechanical and mechanical properties, aging resistance, and toughness.

[0024] (3) The halogen-free flame-retardant PC-based alloy material disclosed in the present invention, the sulfonic acid groups on 2,7-anthraquinone disulfonic acid and piperazine-N,N'-bis(2-hydroxypropanesulfonic acid) can react chemically with other raw materials containing benzene rings under the catalytic action of a catalyst to form an interpenetrating network structure. At the same time, carbonate, bisphenol A, sulfone group, piperazine, anthraquinone, phosphaphenanthrene, hyperbranched polysiloxane, benzotriazole, cyanobenzothiazole, polyurethane and dicyclohexylmethane structures are introduced into the molecular structure of the alloy material. Under the multiple effects of electronic effect, steric effect and conjugation effect, these structures make the flame retardant effect of the alloy material product more significant, the mechanical properties, environmental performance and impact toughness are better, the aging resistance is more excellent, and the service life is longer. DETAILED DESCRIPTION

[0025] The following description is intended to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are merely examples, and those skilled in the art may conceive of other obvious variations.

[0026] Example 1

[0027] A halogen-free flame-retardant PC-based alloy material is made from the following raw materials, measured in parts by weight: 65 parts of bisphenol A polycarbonate, 25 parts of a functional polymer, 10 parts of a hyperbranched polysiloxane containing a phosphaphenanthrene structure, 3 parts of a coupling agent, 25 parts of a filler, 0.3 parts of an antioxidant, 0.3 parts of a lubricant, 0.5 parts of a catalyst A, 0.8 parts of 2,7-anthraquinone disulfonic acid, 1 part of piperazine-N,N'-bis(2-hydroxypropanesulfonic acid), and 1 part of a compatibilizer; the functional polymer includes structural units introduced from the following monomers: N-[(4-methyl-1H-benzotriazol-1-yl)methyl]diethanolamine, 4,6-hydroxy-2-cyanobenzothiazole, and 4,4-diisocyanate dicyclohexylmethane; the bisphenol A polycarbonate is Covestro 2456 polycarbonate.

[0028] The preparation method of the functional polymer comprises the following steps: mixing N-[(4-methyl-1H-benzotriazole-1-yl)methyl]diethanolamine, 4,6-hydroxy-2-cyanobenzothiazole, 4,4-diisocyanate dicyclohexylmethane, catalyst B, and a high-boiling-point solvent; stirring and reacting at 80°C for 1 hour in an inert gas atmosphere; then heating to 100°C and continuing stirring and reacting for 8 hours; then rotary evaporating to remove the solvent; washing with ether three times; and rotary evaporating to remove the residual ether. ether to obtain a functional polymer; the molar ratio of N-[(4-methyl-1H-benzotriazole-1-yl)methyl]diethanolamine, 4,6-hydroxy-2-cyanobenzothiazole, 4,4-diisocyanate dicyclohexylmethane, catalyst B, and high boiling point solvent is 0.7:0.3:1:0.8:10; the catalyst is dibutyltin dilaurate; the high boiling point solvent is dimethyl sulfoxide; the inert gas is nitrogen; GPC test shows that the M n =15380g / mol, M W / M n =1.317; quantitative elemental analysis confirmed that the molar ratio of the structural units introduced into the polymer by N-[(4-methyl-1H-benzotriazol-1-yl)methyl]diethanolamine, 4,6-hydroxy-2-cyanobenzothiazole, and 4,4-diisocyanate dicyclohexylmethane was 0.7:0.3:1.

[0029] The hyperbranched polysiloxane containing a phosphorus-phenanthrene structure is prepared according to the method of Example 1 of the Chinese invention patent with authorization publication number CN102432884B; the coupling agent is a silane coupling agent KH550; the filler is a mixture of aluminum hydroxide flame retardant VK-LA50 and nano-boron fiber in a mass ratio of 0.8:1; the nano-boron fiber has an average diameter of 300 nm and an aspect ratio of 15:1; the antioxidant is antioxidant 1010; the lubricant is pentaerythritol stearate; the catalyst A is a mixture of phosphorus pentoxide and polyphosphoric acid in a mass ratio of 1:1; and the compatibilizer is maleic anhydride grafted polypropylene, selected from MAH-g-PP with the brand EXXELOR PO1020 provided by Exxon in the United States.

[0030] A preparation method of the halogen-free flame-retardant PC-based alloy material comprises the following steps: uniformly mixing raw materials by weight to obtain a mixture, placing the mixture into a hot pressing mold, preheating the mixture at 80°C for 5 minutes, and then hot pressing the mixture at 175°C and 10 MPa for 15 minutes; subsequently heating the mixture to 230°C at a heating rate of 5°C / min, holding the temperature for 3 minutes, and then heating the mixture to 280°C at a heating rate of 15°C / min, holding the temperature for 1 minute, and maintaining the pressure during the heating process; after the gradient heating is completed, allowing the mold to cool naturally while maintaining the pressure, releasing the pressure when the temperature drops to 60°C, and then continuing to cool to room temperature to obtain the halogen-free flame-retardant PC-based alloy material.

[0031] Example 2

[0032] A halogen-free flame-retardant PC-based alloy material is made from the following raw materials, measured in parts by weight: 67 parts of bisphenol A polycarbonate, 28 parts of a functional polymer, 12 parts of a hyperbranched polysiloxane containing a phosphaphenanthrene structure, 3.5 parts of a coupling agent, 27 parts of a filler, 0.35 parts of an antioxidant, 0.4 parts of a lubricant, 0.6 parts of a catalyst A, 0.9 parts of 2,7-anthraquinone disulfonic acid, 1.2 parts of piperazine-N,N'-bis(2-hydroxypropanesulfonic acid), and 2 parts of a compatibilizer; the functional polymer includes structural units introduced from the following monomers: N-[(4-methyl-1H-benzotriazol-1-yl)methyl]diethanolamine, 4,6-hydroxy-2-cyanobenzothiazole, and 4,4-diisocyanate dicyclohexylmethane; and the bisphenol A polycarbonate is Covestro 2456 polycarbonate.

[0033] The preparation method of the functional polymer comprises the following steps: mixing N-[(4-methyl-1H-benzotriazole-1-yl)methyl]diethanolamine, 4,6-hydroxy-2-cyanobenzothiazole, 4,4-diisocyanate dicyclohexylmethane, catalyst B, and a high-boiling-point solvent, stirring and reacting at 83° C. for 1.5 hours in an inert gas atmosphere, then heating to 105° C. and continuing stirring and reacting for 8.5 hours, then rotary evaporating to remove the solvent, and washing with ether four times. The residual ether was then removed by rotary evaporation to obtain a functional polymer; the molar ratio of N-[(4-methyl-1H-benzotriazole-1-yl)methyl]diethanolamine, 4,6-hydroxy-2-cyanobenzothiazole, 4,4-diisocyanate dicyclohexylmethane, catalyst B, and high-boiling-point solvent was 0.7:0.3:1:0.9:11; the catalyst was stannous octoate; the high-boiling-point solvent was N,N-dimethylformamide; and the inert gas was helium.

[0034] The hyperbranched polysiloxane containing a phosphorus-phenanthrene structure is prepared according to the method of Example 1 of the Chinese invention patent with authorization publication number CN102432884B; the coupling agent is a silane coupling agent KH560; the filler is a mixture of aluminum hydroxide flame retardant VK-LA50 and nano-boron fiber in a mass ratio of 0.9:1; the nano-boron fiber has an average diameter of 350 nm and an aspect ratio of 17:1; the antioxidant is antioxidant 168; the lubricant is zinc stearate; the catalyst A is a mixture of phosphorus pentoxide and polyphosphoric acid in a mass ratio of 1.3:1; and the compatibilizer is maleic anhydride grafted polypropylene, selected from MAH-g-PP with the brand EXXELOR PO1020 provided by Exxon in the United States.

[0035] A preparation method of the halogen-free flame-retardant PC-based alloy material comprises the following steps: uniformly mixing raw materials by weight to obtain a mixture, placing the mixture into a hot pressing mold, preheating the mixture at 85°C for 6 minutes, and then hot pressing the mixture at 178°C and 13 MPa for 18 minutes; subsequently heating the mixture to 235°C at a heating rate of 7°C / min, holding the temperature for 3.5 minutes, and then heating the mixture to 285°C at a heating rate of 16°C / min, holding the temperature for 1.5 minutes, and maintaining the pressure during the heating process; after the gradient heating is completed, allowing the mold to cool naturally while maintaining the pressure, releasing the pressure when the temperature drops to 65°C, and then continuing to cool to room temperature to obtain the halogen-free flame-retardant PC-based alloy material.

[0036] Example 3

[0037] A halogen-free flame-retardant PC-based alloy material is made from the following raw materials, measured in parts by weight: 70 parts of bisphenol A polycarbonate, 30 parts of a functional polymer, 13 parts of a hyperbranched polysiloxane containing a phosphaphenanthrene structure, 4 parts of a coupling agent, 30 parts of a filler, 0.4 parts of an antioxidant, 0.6 parts of a lubricant, 0.8 parts of a catalyst A, 1 part of 2,7-anthraquinone disulfonic acid, 1.5 parts of piperazine-N,N'-bis(2-hydroxypropanesulfonic acid), and 2.5 parts of a compatibilizer; the functional polymer includes structural units introduced from the following monomers: N-[(4-methyl-1H-benzotriazol-1-yl)methyl]diethanolamine, 4,6-hydroxy-2-cyanobenzothiazole, and 4,4-diisocyanate dicyclohexylmethane; and the bisphenol A polycarbonate is Covestro 2456 polycarbonate.

[0038] The preparation method of the functional polymer comprises the following steps: mixing N-[(4-methyl-1H-benzotriazole-1-yl)methyl]diethanolamine, 4,6-hydroxy-2-cyanobenzothiazole, 4,4-diisocyanate dicyclohexylmethane, catalyst B, and a high boiling point solvent, stirring and reacting at 85°C in an inert gas atmosphere for 2 hours, then heating to 110°C and continuing stirring and reacting for 9 hours, then rotary evaporating to remove the solvent, washing with ether 5 times, and rotary evaporating again. Residual ether is removed to obtain a functional polymer; the molar ratio of N-[(4-methyl-1H-benzotriazole-1-yl)methyl]diethanolamine, 4,6-hydroxy-2-cyanobenzothiazole, 4,4-diisocyanate dicyclohexylmethane, catalyst B, and high-boiling-point solvent is 0.7:0.3:1:1:13; the catalyst is dibutyltin dilaurate; the high-boiling-point solvent is N,N-dimethylacetamide; and the inert gas is neon.

[0039] The hyperbranched polysiloxane containing a phosphorus-phenanthrene structure is prepared according to the method of Example 1 of the Chinese invention patent with authorization publication number CN102432884B; the coupling agent is a silane coupling agent KH570; the filler is a mixture of aluminum hydroxide flame retardant VK-LA50 and nano-boron fiber in a mass ratio of 1:1; the nano-boron fiber has an average diameter of 400 nm and an aspect ratio of 20:1; the antioxidant is antioxidant 1076; the lubricant is ethylene bisstearamide; the catalyst A is a mixture of phosphorus pentoxide and polyphosphoric acid in a mass ratio of 1.5:1; the compatibilizer is maleic anhydride grafted polypropylene, selected from MAH-g-PP with the brand EXXELOR PO1020 provided by Exxon in the United States.

[0040] A preparation method of the halogen-free flame-retardant PC-based alloy material comprises the following steps: uniformly mixing raw materials by weight to obtain a mixture, placing the mixture into a hot pressing mold, preheating the mixture at 90°C for 8 minutes, and then hot pressing the mixture at 180°C and 15MPa for 20 minutes; subsequently heating the mixture to 240°C at a heating rate of 8°C / min, holding the temperature for 4 minutes, and then heating the mixture to 290°C at a heating rate of 18°C / min, holding the temperature for 2 minutes, and maintaining the pressure during the heating process; after the gradient heating is completed, allowing the mold to cool naturally while maintaining the pressure, releasing the pressure when the temperature drops to 70°C, and then continuing to cool to room temperature to obtain the halogen-free flame-retardant PC-based alloy material.

[0041] Example 4

[0042] A halogen-free flame-retardant PC-based alloy material is made from the following raw materials, measured in parts by weight: 73 parts of bisphenol A polycarbonate, 33 parts of a functional polymer, 14 parts of a hyperbranched polysiloxane containing a phosphaphenanthrene structure, 4.5 parts of a coupling agent, 33 parts of a filler, 0.45 parts of an antioxidant, 0.7 parts of a lubricant, 0.9 parts of a catalyst A, 1.1 parts of 2,7-anthraquinone disulfonic acid, 1.8 parts of piperazine-N,N'-bis(2-hydroxypropanesulfonic acid), and 3.5 parts of a compatibilizer; the functional polymer includes structural units introduced from the following monomers: N-[(4-methyl-1H-benzotriazol-1-yl)methyl]diethanolamine, 4,6-hydroxy-2-cyanobenzothiazole, and 4,4-diisocyanate dicyclohexylmethane; and the bisphenol A polycarbonate is Covestro 2456 polycarbonate.

[0043] The preparation method of the functional polymer comprises the following steps: mixing N-[(4-methyl-1H-benzotriazole-1-yl)methyl]diethanolamine, 4,6-hydroxy-2-cyanobenzothiazole, 4,4-diisocyanate dicyclohexylmethane, catalyst B, and a high-boiling-point solvent, stirring and reacting at 88° C. for 2.5 hours in an inert gas atmosphere, then heating to 115° C. and continuing stirring and reacting for 9.5 hours, then rotary evaporating to remove the solvent, washing with ether 6 times, and then rotary evaporating to remove the residual ether to obtain the functional polymer; the N-[( The molar ratio of 4-methyl-1H-benzotriazol-1-yl)methyl]diethanolamine, 4,6-hydroxy-2-cyanobenzothiazole, 4,4-diisocyanate dicyclohexylmethane, catalyst B, and high-boiling-point solvent is 0.7:0.3:1:1.1:14; the catalyst is a mixture of dibutyltin dilaurate and stannous octoate in a mass ratio of 1:2; the high-boiling-point solvent is a mixture of dimethyl sulfoxide, N,N-dimethylformamide, and N,N-dimethylacetamide in a mass ratio of 1:3:2; and the inert gas is argon.

[0044] The hyperbranched polysiloxane containing a phosphaphenanthrene structure is prepared according to the method of Example 1 of the Chinese invention patent with authorization announcement number CN102432884B; the coupling agent is a mixture of silane coupling agent KH550, silane coupling agent KH560, and silane coupling agent KH570 in a mass ratio of 1:1:2; the filler is a mixture of aluminum hydroxide flame retardant VK-LA50 and nano-boron fiber in a mass ratio of 1.1:1; the average diameter of the nano-boron fiber is 450nm m, with an aspect ratio of 23:1; the antioxidant is a mixture of antioxidant 1010, antioxidant 168, and antioxidant 1076 in a mass ratio of 1:3:5; the lubricant is a mixture of pentaerythritol stearate, zinc stearate, and ethylene bisstearamide in a mass ratio of 2:1:3; the catalyst A is a mixture of phosphorus pentoxide and polyphosphoric acid in a mass ratio of 1.8:1; the compatibilizer is maleic anhydride grafted polypropylene, selected from MAH-g-PP with the brand EXXELOR PO1020 provided by Exxon in the United States.

[0045] A preparation method of the halogen-free flame-retardant PC-based alloy material comprises the following steps: uniformly mixing raw materials by weight to obtain a mixture, placing the mixture into a hot pressing mold, preheating the mixture at 95°C for 9 minutes, and then hot pressing the mixture at 183°C and 18 MPa for 23 minutes; subsequently heating the mixture to 245°C at a heating rate of 9°C / min, holding the temperature for 4.5 minutes, and then heating the mixture to 295°C at a heating rate of 19°C / min, holding the temperature for 2.5 minutes, and maintaining the pressure during the heating process; after the gradient heating is completed, allowing the mold to cool naturally while maintaining the pressure, releasing the pressure when the temperature drops to 75°C, and then continuing to cool to room temperature to obtain the halogen-free flame-retardant PC-based alloy material.

[0046] Example 5

[0047] A halogen-free flame-retardant PC-based alloy material is made from the following raw materials, measured in parts by weight: 75 parts of bisphenol A polycarbonate, 35 parts of a functional polymer, 15 parts of a hyperbranched polysiloxane containing a phosphaphenanthrene structure, 5 parts of a coupling agent, 35 parts of a filler, 0.5 parts of an antioxidant, 0.8 parts of a lubricant, 1 part of a catalyst A, 1.2 parts of 2,7-anthraquinone disulfonic acid, 2 parts of piperazine-N,N'-bis(2-hydroxypropanesulfonic acid), and 4 parts of a compatibilizer; the functional polymer includes structural units introduced from the following monomers: N-[(4-methyl-1H-benzotriazol-1-yl)methyl]diethanolamine, 4,6-hydroxy-2-cyanobenzothiazole, and 4,4-diisocyanate dicyclohexylmethane; the bisphenol A polycarbonate is Covestro 2456 polycarbonate.

[0048] The preparation method of the functional polymer comprises the following steps: mixing N-[(4-methyl-1H-benzotriazole-1-yl)methyl]diethanolamine, 4,6-hydroxy-2-cyanobenzothiazole, 4,4-diisocyanate dicyclohexylmethane, catalyst B, and a high boiling point solvent, stirring and reacting at 90° C. for 3 hours in an inert gas atmosphere, then heating to 120° C. and continuing stirring and reacting for 10 hours, then rotary evaporating to remove the solvent, washing with ether 6 times, and rotary evaporating to remove the solvent. Residual ether is removed to obtain a functional polymer; the molar ratio of N-[(4-methyl-1H-benzotriazole-1-yl)methyl]diethanolamine, 4,6-hydroxy-2-cyanobenzothiazole, 4,4-diisocyanate dicyclohexylmethane, catalyst B, and high-boiling-point solvent is 0.7:0.3:1:1.2:15; the catalyst is dibutyltin dilaurate; the high-boiling-point solvent is N,N-dimethylformamide; and the inert gas is nitrogen.

[0049] The hyperbranched polysiloxane containing a phosphorus-phenanthrene structure is prepared according to the method of Example 1 of the Chinese invention patent with authorization publication number CN102432884B; the coupling agent is a silane coupling agent KH560; the filler is a mixture of aluminum hydroxide flame retardant VK-LA50 and nano-boron fiber in a mass ratio of 1.2:1; the nano-boron fiber has an average diameter of 500 nm and an aspect ratio of 25:1; the antioxidant is antioxidant 1010; the lubricant is pentaerythritol stearate; the catalyst A is a mixture of phosphorus pentoxide and polyphosphoric acid in a mass ratio of 2:1; and the compatibilizer is maleic anhydride grafted polypropylene, selected from MAH-g-PP with the brand EXXELOR PO1020 provided by Exxon in the United States.

[0050] A preparation method of the halogen-free flame-retardant PC-based alloy material comprises the following steps: uniformly mixing raw materials by weight to obtain a mixture, placing the mixture into a hot pressing mold, preheating the mixture at 100°C for 10 minutes, and then hot pressing the mixture at 185°C and 20 MPa for 25 minutes; subsequently heating the mixture to 250°C at a heating rate of 10°C / min, holding the temperature for 5 minutes, then heating the mixture to 300°C at a heating rate of 20°C / min, holding the temperature for 3 minutes, and maintaining the pressure during the heating process; after the gradient heating is completed, allowing the mold to cool naturally while maintaining the pressure, releasing the pressure when the temperature drops to 80°C, and then continuing to cool to room temperature to obtain the halogen-free flame-retardant PC-based alloy material.

[0051] Comparative Example 1

[0052] This example provides a halogen-free flame-retardant PC-based alloy material, which is basically the same as Example 1, except that an equal amount of N-[(4-methyl-1H-benzotriazole-1-yl)methyl]diethanolamine is used instead of 4,6-hydroxy-2-cyanobenzothiazole, and 2,7-anthraquinone disulfonic acid is not added.

[0053] Comparative Example 2

[0054] This example provides a halogen-free flame-retardant PC-based alloy material, which is basically the same as Example 1, except that an equal amount of 4,6-hydroxy-2-cyanobenzothiazole is used instead of N-[(4-methyl-1H-benzotriazole-1-yl)methyl]diethanolamine, and no piperazine-N,N'-bis(2-hydroxypropanesulfonic acid) is added.

[0055] In order to further illustrate the beneficial technical effects of the halogen-free flame-retardant PC-based alloy materials involved in each embodiment of the present invention, relevant performance tests were conducted on the halogen-free flame-retardant PC-based alloy materials involved in Examples 1-5 and Comparative Examples 1-2; the test methods are as follows:

[0056] (1) Tensile properties: The tensile strength test was performed according to GB / T 1040.1-2018 at a tensile speed of 5 mm / s.

[0057] (2) Notched impact strength: tested in accordance with GB / T1843-2008 standard, with specimen dimensions of (80±2) mm × (10±0.2) mm × (4±0.2) mm, notch bottom radius of 0.25±0.05 mm, and notch retention thickness of 8.0±0.2 mm.

[0058] (3) Aging resistance: Each example of halogen-free flame-retardant PC-based alloy material was subjected to a carbon arc lamp aging test according to GB / T16422.4-1996, using a continuous 720-h illumination test, a blackboard temperature of (65±3)°C, a relative humidity of (50±5)%, and then the tensile strength retention rate of the product was measured after cooling to room temperature. The tensile strength retention rate = tensile strength after aging / tensile strength before aging × 100%. The greater the tensile strength retention rate, the better the aging resistance. The tensile strength test refers to (1) the test method of tensile properties.

[0059] (4) Flame retardancy: tested according to UL94 standard.

[0060] Table 1 Test results of halogen-free flame retardant PC-based alloy material properties

[0061] project tensile strength Notched impact strength Aging resistance flame retardancy unit MPa <![CDATA[KJ / m 2 ]]> ％ class Example 1 95.2 88.0 99.27 V-0 Example 2 96.0 88.5 99.38 V-0 Example 3 96.6 89.2 99.43 V-0 Example 4 97.8 89.6 99.73 V-0 Example 5 98.3 89.9 99.99 V-0 Comparative Example 1 85.2 80.7 97.58 V-1 Comparative Example 2 83.9 78.3 96.39 V-1

[0062] As can be seen from Table 1, the halogen-free flame-retardant PC-based alloy materials involved in the various embodiments of the present invention have higher mechanical properties and notched impact strength, better flame retardancy and aging resistance; the combined use of N-[(4-methyl-1H-benzotriazol-1-yl)methyl]diethanolamine, 4,6-hydroxy-2-cyanobenzothiazole, 2,7-anthraquinonedisulfonic acid, and piperazine-N,N'-bis(2-hydroxypropanesulfonic acid) is beneficial to improving the above properties.

[0063] The above embodiments are only for illustrating the technical concept and features of the present invention. Their purpose is to enable people familiar with this technology to understand the content of the present invention and implement it accordingly. They are not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the scope of protection of the present invention.

Claims

1. A halogen-free flame retardant PC-based alloy material, characterized in that: The invention comprises the following raw materials in parts by weight: 65-75 parts of bisphenol A polycarbonate, 25-35 parts of functional polymer, 10-15 parts of hyperbranched polysiloxane containing a phosphaphenanthrene structure, 3-5 parts of coupling agent, 25-35 parts of filler, 0.3-0.5 parts of antioxidant, 0.3-0.8 parts of lubricant, 0.5-1 parts of catalyst A, 0.8-1.2 parts of 2,7-anthraquinone disulfonic acid, 1-2 parts of piperazine-N,N'-bis(2-hydroxypropanesulfonic acid), and 1-4 parts of compatibilizer; the functional polymer comprises structural units introduced from the following monomers: N-[(4-methyl-1H-benzotriazole-1-yl)methyl]diethanolamine, 4,6-hydroxy-2-cyanobenzothiazole, and 4,4-diisocyanate dicyclohexylmethane.

2. The halogen-free flame-retardant PC-based alloy material according to claim 1, characterized in that: The bisphenol A polycarbonate is Covestro 2456 polycarbonate.

3. The halogen-free flame-retardant PC-based alloy material according to claim 1, characterized in that: The preparation method of the functional polymer comprises the following steps: mixing N-[(4-methyl-1H-benzotriazole-1-yl)methyl]diethanolamine, 4,6-hydroxy-2-cyanobenzothiazole, 4,4-diisocyanate dicyclohexylmethane, catalyst B, and a high-boiling-point solvent; stirring and reacting the mixture at 80-90° C. in an inert gas atmosphere for 1-3 hours; then heating the mixture to 100-120° C. and continuing stirring and reacting the mixture for 8-10 hours; then rotary evaporating the mixture to remove the solvent; washing the mixture with ether for 3-6 times; and then rotary evaporating the mixture to remove the residual ether to obtain the functional polymer.

4. The halogen-free flame-retardant PC-based alloy material according to claim 3, characterized in that: The molar ratio of the N-[(4-methyl-1H-benzotriazole-1-yl)methyl]diethanolamine, 4,6-hydroxy-2-cyanobenzothiazole, 4,4-diisocyanate dicyclohexylmethane, catalyst B, and high boiling point solvent is 0.7:0.3:1:(0.8-1.2):(10-15).

5. The halogen-free flame-retardant PC-based alloy material according to claim 3, characterized in that: The catalyst B is at least one of dibutyltin dilaurate and stannous octoate; the high boiling point solvent is at least one of dimethyl sulfoxide, N,N-dimethylformamide, and N,N-dimethylacetamide; and the inert gas is any one of nitrogen, helium, neon, and argon.

6. The halogen-free flame-retardant PC-based alloy material according to claim 1, characterized in that: The coupling agent is at least one of silane coupling agent KH550, silane coupling agent KH560, and silane coupling agent KH570; the filler is a mixture of aluminum hydroxide flame retardant VK-LA50 and nano-boron fiber in a mass ratio of (0.8-1.2):1; the average diameter of the nano-boron fiber is 300-500nm, and the aspect ratio is (15-25):

1.

7. The halogen-free flame-retardant PC-based alloy material according to claim 1, characterized in that: The antioxidant is at least one of antioxidant 1010, antioxidant 168, and antioxidant 1076; the lubricant is at least one of pentaerythritol stearate, zinc stearate, and ethylene bisstearamide.

8. The halogen-free flame-retardant PC-based alloy material according to claim 1, characterized in that: The catalyst A is prepared by mixing phosphorus pentoxide and polyphosphoric acid in a mass ratio of (1-2):

1.

9. The halogen-free flame-retardant PC-based alloy material according to claim 1, characterized in that: The compatibilizer is maleic anhydride grafted polypropylene, selected from MAH-g-PP with the brand name EXXELOR PO1020 provided by Exxon in the United States.

10. A method for preparing a halogen-free flame-retardant PC-based alloy material according to any one of claims 1 to 9, characterized in that: The method comprises the following steps: uniformly mixing raw materials according to parts by weight to obtain a mixture, placing the mixture into a hot pressing mold, preheating the mixture at 80-100°C for 5-10 minutes, and then hot pressing the mixture at 175-185°C and 10-20 MPa for 15-25 minutes; subsequently heating the mixture to 230-250°C at a heating rate of 5-10°C / min, keeping the temperature for 3-5 minutes, and then heating the mixture to 280-300°C at a heating rate of 15-20°C / min, keeping the temperature for 1-3 minutes, and continuously maintaining the pressure during the heating process; after the gradient heating is completed, allowing the mold to cool naturally while maintaining the pressure, releasing the pressure when the temperature drops to 60-80°C, and then continuing to cool to room temperature to obtain a halogen-free flame-retardant PC-based alloy material.