Flame-retardant polycarbonate material and method for producing the same

Abstract

The application relates to the technical field of high polymer materials, and discloses a flame-retardant polycarbonate material and a preparation method thereof. The flame-retardant polycarbonate material is obtained by adding polycarbonate, sodium sulfonate modified tris(2-acryloyloxyethyl) isocyanurate, sulfur-containing modified bisphenol fluorene and antioxidant 1068 into a double-screw extruder, extruding and granulating, and then performing mold pressing into a flat vulcanizing machine to obtain the flame-retardant polycarbonate material. The sulfur element, the phosphorus element, the carbon nanotube structure and the triazine group contained in the sodium sulfonate modified tris(2-acryloyloxyethyl) isocyanurate and the sulfur-containing modified bisphenol fluorene all have good flame-retardant effects, and jointly form a flame-retardant system; and the sulfonate group can catalyze polycarbonate to isomerize and crosslink into carbon, so that the polycarbonate material has higher carbon formation, and better flame-retardant effect.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of high molecular materials, in particular to a flame-retardant polycarbonate material and a preparation method thereof. BACKGROUND

[0002] Polycarbonate is a biodegradable polymer with high strength, high toughness, high heat resistance, shock resistance, good processing performance, non-toxicity, weather resistance, electrical insulation and other characteristics. It is a thermoplastic engineering plastic with excellent comprehensive performance. Although it has certain flame retardancy, the flame retardant effect is limited, which greatly limits its application. For example, patent CN114790326B discloses a reinforced polycarbonate material and a preparation method and application thereof. The reinforced polycarbonate material has good toughness and still maintains high strength of the material after multiple bending, but the flame retardant effect is not improved. SUMMARY

[0003] (I) Technical problems to be solved

[0004] In view of the deficiencies of the prior art, the present application provides a flame-retardant polycarbonate material and a preparation method thereof, which has good flame retardant effect.

[0005] (II) Technical solutions

[0006] To achieve the above-mentioned purpose, the present application provides the following technical solutions: a flame-retardant polycarbonate material, comprising the following components by weight: 50-80 parts by weight of polycarbonate, 3-5 parts by weight of sodium sulfonate modified tris(2-acryloyloxyethyl) isocyanurate, 4-6 parts by weight of sulfur-containing modified bisphenol fluorene, and 0.6-0.8 parts by weight of antioxidant 1068.

[0007] Preferably, the preparation method of the sodium sulfonate modified tris(2-acryloyloxyethyl) isocyanurate is as follows:

[0008] (1) Add tris(2-acryloyloxyethyl) isocyanurate to N,N-dimethylformamide solvent, stir and disperse, then add mercaptoethylamine and benzoin dimethyl ether photoinitiator, irradiate under 365nm ultraviolet light at 25-45℃ for 3-6h, then centrifuge, wash and dry to obtain intermediate 1;

[0009] (2) Dissolve intermediate 1 and 1,3-propane sultone in 1,4-dioxane solvent, then drop 3-5% sodium hydroxide solution by mass fraction, heat to 75-90℃ and react for 6-14h, then drop and remove the solvent by reduced pressure concentration after reaction, recrystallize the crude product in ethanol to obtain sodium sulfonate modified tris(2-acryloyloxyethyl) isocyanurate.

[0010] Preferably, in step (1), the mass ratio of tris(2-acryloyloxyethyl) isocyanurate, mercaptoethylamine, and benzoin dimethyl ether photoinitiator is 1:2.1-3.4:0.01-0.02.

[0011] Preferably, the mass ratio of intermediate 1 to 1,3-propanesulfonyl lactone in step (2) is 1.2-1.4:1.

[0012] Preferably, the method for preparing the sulfur-modified bisphenol fluorene is as follows:

[0013] S1. Under a nitrogen atmosphere, 5-10 parts by weight of bisphenol fluorene and 0.02-0.07 parts by weight of triethylamine are added to dichloromethane solvent and stirred at 8-12°C until fully dissolved. Then, 4-9 parts by weight of phenylphosphodichloro are added and the reaction is stirred for 10-14 hours. After the reaction is completed, the mixture is dried to obtain intermediate 2.

[0014] S2. Add itaconic acid to N,N-dimethylformamide solvent, stir evenly, and continue to add intermediate 2 and p-toluenesulfonic acid catalyst. React at 70-85℃ for 6-10h. After the reaction is completed, distill under reduced pressure, wash and dry to obtain bisphenol fluorene modified itaconic acid.

[0015] S3. Sodium dodecyl sulfate emulsifier and vinyl carbon nanotubes were added to deionized water and dispersed evenly. Then, bisphenol fluorene-modified itaconic acid and 1,3,5-triacryloylhexahydro-1,3,5-triazine were added. Nitrogen gas was introduced for protection, and then azobisisobutyronitrile initiator was added. The reaction was carried out at 80-110℃ for 3-5 hours. The mixture was washed with deionized water and ethanol in sequence and dried to obtain sulfur-modified bisphenol fluorene.

[0016] Preferably, the mass ratio of itaconic acid, intermediate 2, and p-toluenesulfonic acid catalyst in S2 is 1:1.2-1.5:0.02-0.04.

[0017] Preferably, the mass ratio of sodium dodecyl sulfate emulsifier, vinyl carbon nanotubes, bisphenol fluorene-modified itaconic acid, 1,3,5-triacryloyl hexahydro-1,3,5-triazine, and azobisisobutyronitrile initiator in S3 is 0.02-0.03:0.9-1.1:1:0.4-0.8:0.01-0.03.

[0018] Preferably, the preparation method of the flame-retardant polycarbonate material is as follows: polycarbonate, sodium sulfonate modified tris(2-acryloyloxyethyl) isocyanurate, sulfur-modified bisphenol fluorene, and antioxidant 1068 are added to a twin-screw extruder and extruded and granulated at 170-180°C. Then, the granules are molded in a flat vulcanizing machine at 10-12 MPa pressure and 175-180°C to obtain the flame-retardant polycarbonate material.

[0019] (iii) Beneficial technical effects

[0020] This invention involves adding polycarbonate, sodium sulfonate-modified tris(2-acryloyloxyethyl) isocyanurate, sulfur-modified bisphenol fluorene, and antioxidant 1068 into a twin-screw extruder for extrusion granulation, and then molding the granules in a flat vulcanizing machine to obtain flame-retardant polycarbonate material.

[0021] An addition reaction was performed between the alkenyl group in tris(2-acryloyloxyethyl)isocyanurate and the thiol group in mercaptoethylamine to introduce an amino group, yielding intermediate 1. The amino group in intermediate 1 was reacted with 1,3-propane sulfonyl lactone to obtain sodium sulfonate-modified tris(2-acryloyloxyethyl)isocyanurate. The phenolic hydroxyl group in bisphenol fluorene was reacted with the chlorine in phenylphosphine dichloride to obtain intermediate 2. Itaconic acid was reacted with the phenolic hydroxyl group in intermediate 2 to introduce an alkenyl group, thus obtaining bisphenol fluorene-modified itaconic acid. Vinyl carbon nanotubes, bisphenol fluorene-modified itaconic acid, and 1,3,5-triacryloylhexahydro-1,3,5-triazine were polymerized to obtain sulfur-containing modified bisphenol fluorene, which also improved the degree of substitution of carbon nanotubes, resulting in better flame retardant performance.

[0022] The sulfur, phosphorus, carbon nanotube structure, and triazine groups contained in sodium sulfonate-modified tris(2-acryloyloxyethyl)isocyanurate and sulfur-containing modified bisphenol fluorene all have good flame retardant effects and together constitute a flame retardant system. Furthermore, the sulfonate groups can catalyze the isomerization and cross-linking of polycarbonate to form carbon, thereby giving the polycarbonate material higher carbonization properties and achieving better flame retardant effects. Detailed Implementation

[0023] The preparation process of vinyl carbon nanotubes is referenced from the journal "Materials Science and Engineering Plastics", Volume 23, Issue 4, "Surface Vinyl Functionalization of Multi-Wall Carbon Nanotubes": 0.3 g of multi-wall carbon nanotubes were added to 30 mL of 98% concentrated sulfuric acid and 10 mL of 70% concentrated nitric acid, refluxed at 140 °C for 1 h, filtered, washed, and 0.1 g of the resulting acidified carbon nanotubes were weighed and dispersed in 15 mL of acetone and 15 mL of chloroform. 2 mL of triethylamine and 5 mL of acryloyl chloride were added, and the mixture was reacted at 40 °C for 24 h. Then 10 mL of ethanol was added and stirred for 2 h. After filtration and washing, vinyl carbon nanotubes were obtained. Example 1

[0024] (1) Tris(2-acryloyloxyethyl) isocyanurate was added to N,N-dimethylformamide solvent and stirred to disperse. Then mercaptoethylamine and benzoin dimethyl ether photoinitiator were added to it, wherein the mass ratio of tris(2-acryloyloxyethyl) isocyanurate, mercaptoethylamine and benzoin dimethyl ether photoinitiator was 1:2.1:0.01. The mixture was irradiated with 365nm ultraviolet light at 25°C for 3 hours. After the irradiation, the mixture was centrifuged, washed and dried to obtain intermediate 1.

[0025] (2) Intermediate 1 and 1,3-propane sulfonyl lactone were dissolved in 1,4-dioxane solvent, wherein the mass ratio of intermediate 1 to 1,3-propane sulfonyl lactone was 1.2:1. Then, a 3% sodium hydroxide solution was added dropwise, and the temperature was raised to 75°C for 6 hours. After the reaction, the solvent was removed by vacuum concentration. The crude product was recrystallized in ethanol to obtain sodium sulfonate modified tris(2-acryloyloxyethyl) isocyanurate.

[0026] (3) Under a nitrogen atmosphere, 5 parts by weight of bisphenol fluorene and 0.02 parts by weight of triethylamine were added to dichloromethane solvent and stirred at 8°C until fully dissolved. Then, 4 parts by weight of phenylphosphodichloro were added and stirred for 10 hours. After the reaction was completed, the mixture was dried to obtain intermediate 2.

[0027] (4) Add itaconic acid to N,N-dimethylformamide solvent, stir evenly, and continue to add intermediate 2 and p-toluenesulfonic acid catalyst, wherein the mass ratio of itaconic acid, intermediate 2 and p-toluenesulfonic acid catalyst is 1:1.2:0.02. React at 70℃ for 6h, and after the reaction is completed, distill under reduced pressure, wash and dry to obtain bisphenol fluorene modified itaconic acid;

[0028] (5) Sodium dodecyl sulfate emulsifier and vinyl carbon nanotubes were added to deionized water and dispersed evenly. Then, bisphenol fluorene-modified itaconic acid and 1,3,5-triacryloylhexahydro-1,3,5-triazine were added. Nitrogen gas was introduced for protection, and then azobisisobutyronitrile initiator was added. The mass ratio of sodium dodecyl sulfate emulsifier, vinyl carbon nanotubes, bisphenol fluorene-modified itaconic acid, 1,3,5-triacryloylhexahydro-1,3,5-triazine and azobisisobutyronitrile initiator was 0.02:0.9:1:0.4:0.01. The reaction was carried out at 80°C for 3 hours. The mixture was washed with deionized water and ethanol in sequence and dried to obtain sulfur-modified bisphenol fluorene.

[0029] (6) 50 parts by weight of polycarbonate, 3 parts by weight of sodium sulfonate modified tris(2-acryloyloxyethyl) isocyanurate, 4 parts by weight of sulfur-containing modified bisphenol fluorene, and 0.6 parts by weight of antioxidant 1068 are added to a twin-screw extruder and extruded and granulated at 170°C. The granules are then molded in a flat vulcanizing machine at 10 MPa pressure and 175°C to obtain flame-retardant polycarbonate material. Example 2

[0030] (1) Tris(2-acryloyloxyethyl) isocyanurate was added to N,N-dimethylformamide solvent and stirred to disperse. Then mercaptoethylamine and benzoin dimethyl ether photoinitiator were added to it, wherein the mass ratio of tris(2-acryloyloxyethyl) isocyanurate, mercaptoethylamine and benzoin dimethyl ether photoinitiator was 1:3.4:0.02. The mixture was irradiated with 365nm ultraviolet light at 45℃ for 6h. After the irradiation, the mixture was centrifuged, washed and dried to obtain intermediate 1.

[0031] (2) Intermediate 1 and 1,3-propane sulfonyl lactone were dissolved in 1,4-dioxane solvent, wherein the mass ratio of intermediate 1 to 1,3-propane sulfonyl lactone was 1.4:1. Then, a 5% sodium hydroxide solution was added dropwise, and the temperature was raised to 90°C and reacted for 14 h. After the reaction, the solvent was removed by vacuum concentration. The crude product was recrystallized in ethanol to obtain sodium sulfonate modified tris(2-acryloyloxyethyl) isocyanurate.

[0032] (3) Under a nitrogen atmosphere, 10 parts by weight of bisphenol fluorene and 0.07 parts by weight of triethylamine were added to dichloromethane solvent and stirred at 12°C until fully dissolved. Then, 9 parts by weight of phenylphosphodichloro were added and the reaction was stirred for 14 hours. After the reaction was completed, the mixture was dried to obtain intermediate 2.

[0033] (4) Add itaconic acid to N,N-dimethylformamide solvent, stir evenly, and continue to add intermediate 2 and p-toluenesulfonic acid catalyst, wherein the mass ratio of itaconic acid, intermediate 2 and p-toluenesulfonic acid catalyst is 1:1.5:0.04. React at 85℃ for 10h, and after the reaction is completed, distill under reduced pressure, wash and dry to obtain bisphenol fluorene modified itaconic acid;

[0034] (5) Sodium dodecyl sulfate emulsifier and vinyl carbon nanotubes were added to deionized water and dispersed evenly. Then, bisphenol fluorene-modified itaconic acid and 1,3,5-triacryloylhexahydro-1,3,5-triazine were added. Nitrogen gas was introduced for protection, and then azobisisobutyronitrile initiator was added. The mass ratio of sodium dodecyl sulfate emulsifier, vinyl carbon nanotubes, bisphenol fluorene-modified itaconic acid, 1,3,5-triacryloylhexahydro-1,3,5-triazine and azobisisobutyronitrile initiator was 0.03:1.1:1:0.8:0.03. The reaction was carried out at 110°C for 5 hours. The mixture was washed with deionized water and ethanol in sequence and dried to obtain sulfur-modified bisphenol fluorene.

[0035] (6) 80 parts by weight of polycarbonate, 5 parts by weight of sodium sulfonate modified tris(2-acryloyloxyethyl) isocyanurate, 6 parts by weight of sulfur-containing modified bisphenol fluorene, and 0.8 parts by weight of antioxidant 1068 are added to a twin-screw extruder and extruded and granulated at 180°C. The granules are then molded in a flat vulcanizing machine at 12 MPa pressure and 180°C to obtain flame-retardant polycarbonate material. Example 3

[0036] (1) Tris(2-acryloyloxyethyl) isocyanurate was added to N,N-dimethylformamide solvent and stirred to disperse. Then mercaptoethylamine and benzoin dimethyl ether photoinitiator were added to it, wherein the mass ratio of tris(2-acryloyloxyethyl) isocyanurate, mercaptoethylamine and benzoin dimethyl ether photoinitiator was 1:2.63:0.015. The mixture was irradiated with 365nm ultraviolet light at 32℃ for 4h. After the irradiation, the mixture was centrifuged, washed and dried to obtain intermediate 1.

[0037] (2) Intermediate 1 and 1,3-propane sulfonyl lactone were dissolved in 1,4-dioxane solvent, wherein the mass ratio of intermediate 1 and 1,3-propane sulfonyl lactone was 1.3:1. Then, a 4% sodium hydroxide solution was added dropwise, and the temperature was raised to 82℃ and reacted for 10 h. After the reaction, the solvent was removed by vacuum concentration. The crude product was recrystallized in ethanol to obtain sodium sulfonate modified tris(2-acryloyloxyethyl) isocyanurate.

[0038] (3) Under a nitrogen atmosphere, 7.5 parts by weight of bisphenol fluorene and 0.05 parts by weight of triethylamine were added to dichloromethane solvent and stirred at 10°C until fully dissolved. Then, 6 parts by weight of phenylphosphodichloro were added and the reaction was stirred for 12 hours. After the reaction was completed, the mixture was dried to obtain intermediate 2.

[0039] (4) Add itaconic acid to N,N-dimethylformamide solvent, stir evenly, and continue to add intermediate 2 and p-toluenesulfonic acid catalyst, wherein the mass ratio of itaconic acid, intermediate 2 and p-toluenesulfonic acid catalyst is 1:1.35:0.03. React at 80℃ for 8h, and after the reaction is completed, distill under reduced pressure, wash and dry to obtain bisphenol fluorene modified itaconic acid;

[0040] (5) Sodium dodecyl sulfate emulsifier and vinyl carbon nanotubes were added to deionized water and dispersed evenly. Then, bisphenol fluorene-modified itaconic acid and 1,3,5-triacryloyl hexahydro-1,3,5-triazine were added. Nitrogen gas was introduced for protection, and then azobisisobutyronitrile initiator was added. The mass ratio of sodium dodecyl sulfate emulsifier, vinyl carbon nanotubes, bisphenol fluorene-modified itaconic acid, 1,3,5-triacryloyl hexahydro-1,3,5-triazine and azobisisobutyronitrile initiator was 0.025:0.9:1:0.6:0.02. The reaction was carried out at 90°C for 4 hours. The mixture was washed with deionized water and ethanol in sequence and dried to obtain sulfur-modified bisphenol fluorene.

[0041] (6) 65 parts by weight of polycarbonate, 4 parts by weight of sodium sulfonate modified tris(2-acryloyloxyethyl) isocyanurate, 5 parts by weight of sulfur-containing modified bisphenol fluorene, and 0.7 parts by weight of antioxidant 1068 are added to a twin-screw extruder and extruded and granulated at 175°C. The granules are then molded in a flat vulcanizing machine at 11 MPa pressure and 178°C to obtain flame-retardant polycarbonate material.

[0042] Comparative Example 1

[0043] 65 parts by weight of polycarbonate, 5 parts by weight of sulfur-modified bisphenol fluorene, and 0.7 parts by weight of antioxidant 1068 were added to a twin-screw extruder and extruded and granulated at 175°C. The granules were then compressed in a flat vulcanizing machine at 11 MPa pressure and 178°C to obtain flame-retardant polycarbonate material.

[0044] Comparative Example 2

[0045] 65 parts by weight of polycarbonate, 4 parts by weight of sodium sulfonate-modified tris(2-acryloyloxyethyl)isocyanurate, and 0.7 parts by weight of antioxidant 1068 were added to a twin-screw extruder and extruded and granulated at 175°C. The granules were then compression molded in a flat vulcanizing machine at 11 MPa pressure and 178°C to obtain flame-retardant polycarbonate material.

[0046] The limiting oxygen index of flame-retardant polycarbonate materials was tested using an oxygen index meter; horizontal and vertical burning tests were conducted.

[0047] The instrument is used to test the flammability rating of flame-retardant polycarbonate materials.

[0048] Table 1: Tests for flame retardant performance.

[0049] Item Limiting Oxygen Index (%) Flame Class Example 1 32 V-0 Example 2 34 V-0 Example 3 31 V-0 Comparative Example 1 28 V-1 Comparative Example 2 27 V-1

[0050] As shown in Table 1, the flame-retardant polycarbonate materials prepared in Examples 1-3 of the present invention have better flame-retardant effects compared with those prepared in Comparative Examples 1-2.

[0051] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A flame-retardant polycarbonate material, characterized in that, It includes the following components by weight: 50-80 parts by weight of polycarbonate, 3-5 parts by weight of sodium sulfonate modified tris(2-acryloyloxyethyl) isocyanurate, 4-6 parts by weight of sulfur-containing modified bisphenol fluorene, and 0.6-0.8 parts by weight of antioxidant 1068. The method for preparing the sodium sulfonate-modified tris(2-acryloyloxyethyl) isocyanurate is as follows: (1) Add tris(2-acryloyloxyethyl) isocyanurate to N,N-dimethylformamide solvent, stir and disperse, then add mercaptoethylamine and benzoin dimethyl ether photoinitiator, irradiate with 365nm ultraviolet light at 25-45℃ for 3-6h, centrifuge after the end, wash and dry to obtain intermediate 1; (2) Dissolve intermediate 1 and 1,3-propane sulfonyl lactone in 1,4-dioxane solvent, then add sodium hydroxide solution with a mass fraction of 3-5%, heat to 75-90℃ and react for 6-14h. After the reaction, concentrate under reduced pressure to remove the solvent, and recrystallize the crude product in ethanol to obtain sodium sulfonate modified tris(2-acryloyloxyethyl) isocyanurate. In step (1), the mass ratio of tris(2-acryloyloxyethyl) isocyanurate, mercaptoethylamine, and benzoin dimethyl ether photoinitiator is 1:2.1-3.4:0.01-0.02; In step (2), the mass ratio of intermediate 1 to 1,3-propanesulfonyl lactone is 1.2-1.4:1; The method for preparing the sulfur-modified bisphenol fluorene is as follows: S1. Under a nitrogen atmosphere, 5-10 parts by weight of bisphenol fluorene and 0.02-0.07 parts by weight of triethylamine are added to dichloromethane solvent and stirred at 8-12°C until fully dissolved. Then, 4-9 parts by weight of phenylphosphodichloro are added and the reaction is stirred for 10-14 hours. After the reaction is completed, the mixture is dried to obtain intermediate 2. S2. Add itaconic acid to N,N-dimethylformamide solvent, stir evenly, and continue to add intermediate 2 and p-toluenesulfonic acid catalyst. React at 70-85℃ for 6-10h. After the reaction is completed, distill under reduced pressure, wash and dry to obtain bisphenol fluorene modified itaconic acid. S3. Sodium dodecyl sulfate emulsifier and vinyl carbon nanotubes were added to deionized water and dispersed evenly. Then, bisphenol fluorene-modified itaconic acid and 1,3,5-triacryloylhexahydro-1,3,5-triazine were added. Nitrogen gas was introduced for protection, and then azobisisobutyronitrile initiator was added. The reaction was carried out at 80-110℃ for 3-5 hours. The mixture was washed with deionized water and ethanol in sequence and dried to obtain sulfur-modified bisphenol fluorene. The mass ratio of itaconic acid, intermediate 2, and p-toluenesulfonic acid catalyst in S2 is 1:1.2-1.5:0.02-0.04; The mass ratio of sodium dodecyl sulfate emulsifier, vinyl carbon nanotubes, bisphenol fluorene-modified itaconic acid, 1,3,5-triacryloyl hexahydro-1,3,5-triazine, and azobisisobutyronitrile initiator in S3 is 0.02-0.03:0.9-1.1:1:0.4-0.8:0.01-0.

03.

2. A method for preparing the flame-retardant polycarbonate material as described in claim 1, characterized in that, The method for preparing the flame-retardant polycarbonate material is as follows: polycarbonate, sodium sulfonate-modified tris(2-acryloyloxyethyl) isocyanurate, sulfur-modified bisphenol fluorene, and antioxidant 1068 are added to a twin-screw extruder and extruded and granulated at 170-180°C. The granules are then molded in a flat vulcanizing machine at 10-12 MPa pressure and 175-180°C to obtain the flame-retardant polycarbonate material.