High-temperature-resistant environment-friendly flame-retardant polycarbonate modified material and preparation method thereof

Abstract

The invention discloses a high-temperature-resistant environment-friendly flame-retardant polycarbonate modified material and a preparation method thereof, and belongs to the technical field of polycarbonate modified materials. Comprising the following raw materials: cyanuric chloride, taurine, 2 '2-diamino-4' 4-(9-fluorene-based) diphenol and 1, 3-bis (3-aminopropyl)-1, 1, 3, 3-tetramethyldisiloxane, sulfonates are heated and decomposed to release SO2, PC degradation is promoted, oligomers containing phenolic hydroxyl groups are generated, and active functional groups are provided for crosslinking carbon formation; organic silicon migrates to the surface of the material, phenolic hydroxyl groups in a PC degradation product attack silicon-carbon bonds in silane, a silyl ether structure of cross-linked carbon is formed, and the thermal stability of a carbon layer is improved; the nitrogen-containing compound is heated and decomposed to generate N2 and NH3, so that the carbon layer expands, heat in the matrix is coated, heat transfer is inhibited, and flame spreading is prevented; phenyl improves the mechanical property, heat resistance and stability of PC, and has important application value in the fields of electronics and automobiles.

Description

Technical Field

[0001] The present invention belongs to the technical field of polycarbonate modified materials, and in particular relates to a highly heat-resistant, environmentally friendly, flame-retardant polycarbonate modified material and a preparation method thereof. Background Art

[0002] Polycarbonate (PC) is a thermoplastic engineering plastic with excellent comprehensive performance. It has many unique advantages, such as good impact resistance, electrical properties, low water absorption, excellent light transmittance and easy processing and modification. It is widely used in many fields such as electronic products, building materials, automobiles, aircraft, medical products, food packaging, etc., and has become the fastest growing variety among the five general engineering plastics. Polycarbonate has a certain flame retardancy, and the flame retardancy level is UL94 V-2. However, in occasions where fire hazards are prone to occur or in application fields with high requirements for flame retardancy, flame retardant modification of polycarbonate materials is very necessary. Summary of the invention

[0003] The object of the present invention is to provide a method for preparing a highly heat-resistant, environmentally friendly, flame-retardant polycarbonate modified material.

[0004] The purpose of the present invention can be achieved through the following technical solutions:

[0005] A method for preparing a highly heat-resistant, environmentally friendly, flame-retardant polycarbonate modified material, the specific preparation process is as follows:

[0006] S1: Add cyanuric chloride and acetone to a three-necked flask with a mechanical stirring device, maintain the temperature of the system at -5-0°C, and stir until completely dissolved. Dissolve taurine and potassium hydroxide in N-methylpyrrolidone, and slowly drip into the above three-necked flask using a constant pressure dropping funnel. A large amount of precipitate will be produced during the reaction. The pH value is adjusted to 7-8 with a 2 mol / L K2CO3 solution. After the reaction is completed, the intermediate 1 is obtained by filtration, washing, and drying. The ratio of cyanuric chloride, acetone, taurine and potassium hydroxide is 9.28g:100mL:6.92g:3.10g. The specific reaction steps are as follows:

[0007]

[0008] S2: Add 2'2-diamino-4'4-(9-fluorenyl)biphenol and acetone to a three-necked flask with mechanical stirring and nitrogen protection, maintain the temperature at 30-35°C, and stir until fully dissolved. Dissolve intermediate 1 in N-methylpyrrolidone, and slowly drip into the above solution with a constant pressure dropping funnel, adjust the pH value to 7-8 with a 2mol / L K2CO3 solution, and after the reaction, evaporate, filter and dry to obtain intermediate 2, the ratio of 2'2-diamino-4'4-(9-fluorenyl)biphenol, acetone and intermediate 1 is 6.05g:100mL:15.58g. The specific reaction steps are as follows:

[0009]

[0010] S3: 1,3-bis(3-aminopropyl)-1,1,3,3,-tetramethyldisiloxane, K2CO3, and ethanol are placed in a four-necked flask equipped with mechanical stirring, condensation reflux, and nitrogen protection devices. Intermediate 2 is dissolved in N-methylpyrrolidone and added to the above solution in small amounts and multiple times. The reaction temperature is 80-85°C. After the reaction is completed, evaporation, filtration, extraction, and evaporation are performed to finally obtain a nitrogen-sulfur-silicon-containing flame retardant. The ratio of 1,3-bis(3-aminopropyl)-1,1,3,3,-tetramethyldisiloxane, potassium carbonate, and intermediate 2 is 5.50g:5.55g:15.37g. The specific reaction steps are as follows:

[0011]

[0012] S4: The PC pellets are placed in a blast drying oven at 120°C for 10 hours, and the nitrogen-sulfur-silicon flame retardant and polytetrafluoroethylene powder are dried in a vacuum drying oven at 200°C for 6 hours. After the PC pellets, the nitrogen-sulfur-silicon flame retardant and polytetrafluoroethylene powder are uniformly mixed according to the proportion, they are extruded and granulated using a twin-screw extruder. The mass ratio of PC, nitrogen-sulfur-silicon flame retardant and polytetrafluoroethylene powder is 100:5-10:1-5.

[0013] From the perspective of molecular structure, the prepared nitrogen-sulfur-silicon flame retardant contains sulfur, silicon, sulfonate, nitrogen-containing compounds and phenyl, which makes the flame retardant have a certain synergistic effect. The sulfonate releases SO2 acidic gas when heated and decomposes, which promotes PC degradation and generates phenolic hydroxyl-containing polymers, providing active functional groups for cross-linking carbonization. At high temperatures, the silicone flame retardant will migrate to the surface of the material, and the phenolic hydroxyl groups in the surface PC degradation products will attack the silicon-carbon bonds in the silane to form a cross-linked silyl ether structure, thereby improving the thermal stability of the carbon layer. In addition, the nitrogen-containing compounds will decompose when heated to produce N2 and NH3, which will cause the carbon layer to expand and encapsulate the heat inside the matrix, thereby inhibiting heat transfer and preventing the spread of flames. In addition, the presence of phenyl hinders the internal rotation of the molecule, improves the rigidity of the molecular chain, and makes the PC have higher mechanical properties, heat resistance and dimensional stability.

[0014] It should be further explained that the presence of phenyl can also improve the compatibility of nitrogen-sulfur-silicon-containing flame retardants with PC molecules, thereby improving the dispersion effect of the flame retardant in the PC matrix and exerting a more uniform and stable flame retardant performance.

[0015] Another object of the present invention is to provide a polycarbonate modified material prepared by the above preparation method.

[0016] Beneficial effects of the present invention:

[0017] 1. The composite flame retardant containing multiple flame retardant elements of nitrogen, sulfur and silicon prepared by the present invention plays a synergistic flame retardant effect at the same site to achieve local high-efficiency flame retardancy.

[0018] 2. The introduction of silicon, nitrogen, sulfonate and phenyl makes the prepared nitrogen-sulfur-silicon-containing flame retardant have better thermal stability, flame retardancy and mechanical properties.

[0019] Therefore, the flame-retardant polycarbonate modified material containing nitrogen, sulfur and silicon prepared by the present invention has good flame retardancy, mechanical properties and thermal stability, and has important application value in the field of polycarbonate modified materials. DETAILED DESCRIPTION

[0020] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] Embodiment 1

[0022] A method for preparing a highly heat-resistant, environmentally friendly, flame-retardant polycarbonate modified material, the specific preparation process is as follows:

[0023] S1: Add 9.28g of cyanuric chloride and 100mL of acetone to a three-necked flask with a mechanical stirring device, maintain the temperature of the system at -5-0°C, and stir until completely dissolved. Dissolve 6.92g of taurine and 3.10g of potassium hydroxide in N-methylpyrrolidone, and slowly drip into the above three-necked flask using a constant pressure dropping funnel. A large amount of precipitate will be produced during the reaction. The pH value is adjusted to 7-8 with a 2mol / L K2CO3 solution. After the reaction is completed, the intermediate 1 is obtained by filtering, washing, and drying.

[0024] S2: Add 6.05 g of 2'2-diamino-4'4-(9-fluorenyl)biphenol and 100 mL of acetone to a three-necked flask with a mechanical stirrer and a nitrogen protection device, maintain the temperature at 30-35°C, and stir until fully dissolved. Dissolve 15.58 g of intermediate 1 in N-methylpyrrolidone and slowly drip into the above solution using a constant pressure dropping funnel, adjust the pH value to 7-8 with a 2 mol / L K2CO3 solution, and after the reaction is completed, evaporate, filter and dry to obtain intermediate 2.

[0025] S3: 5.50g of 1,3-bis(3-aminopropyl)-1,1,3,3,-tetramethyldisiloxane, 5.55g of K2CO3, and ethanol were placed in a four-necked flask equipped with mechanical stirring, condensation reflux, and nitrogen protection. 15.37g of intermediate 2 was dissolved in N-methylpyrrolidone and added to the above solution in small amounts several times. The reaction temperature was 80-85°C. After the reaction was completed, evaporation, filtration, extraction, and evaporation were performed to finally obtain a nitrogen-sulfur-silicon flame retardant.

[0026] S4: The PC pellets were placed in a blast drying oven at 120°C for 10 hours, and the nitrogen-sulfur-silicon flame retardant and polytetrafluoroethylene powder were dried in a vacuum drying oven at 200°C for 6 hours. First, the masterbatch was prepared, and then the pellets were mixed evenly according to the mass ratio of PC, nitrogen-sulfur-silicon flame retardant and polytetrafluoroethylene being 100:5:1, and then extruded and granulated using a twin-screw extruder.

[0027] Embodiment 2

[0028] A method for preparing a highly heat-resistant, environmentally friendly, flame-retardant polycarbonate modified material, the specific preparation process is as follows:

[0029] S1: Add 9.28g of cyanuric chloride and 100mL of acetone to a three-necked flask with a mechanical stirring device, maintain the temperature of the system at -5-0°C, and stir until completely dissolved. Dissolve 6.92g of taurine and 3.10g of potassium hydroxide in N-methylpyrrolidone, and slowly drip into the above three-necked flask using a constant pressure dropping funnel. A large amount of precipitate will be produced during the reaction. The pH value is adjusted to 7-8 with a 2mol / L K2CO3 solution. After the reaction is completed, the intermediate 1 is obtained by filtering, washing, and drying.

[0030] S2: Add 6.05 g of 2'2-diamino-4'4-(9-fluorenyl)biphenol and 100 mL of acetone to a three-necked flask equipped with a mechanical stirrer and a nitrogen protection device, maintain the temperature at 30-35°C, and stir until fully dissolved. Dissolve 15.58 g of intermediate 1 in N-methylpyrrolidone and slowly drip into the above solution using a constant pressure dropping funnel, adjust the pH value to 7-8 with a 2 mol / L K2CO3 solution, and after the reaction is completed, evaporate, filter and dry to obtain intermediate 2.

[0031] S3: 5.50g of 1,3-bis(3-aminopropyl)-1,1,3,3,-tetramethyldisiloxane, 5.55g of K2CO3, and ethanol were placed in a four-necked flask equipped with mechanical stirring, condensation reflux, and nitrogen protection. 15.37g of intermediate 2 was dissolved in N-methylpyrrolidone and added to the above solution in small amounts several times. The reaction temperature was 80-85°C. After the reaction was completed, evaporation, filtration, extraction, and evaporation were performed to finally obtain a nitrogen-sulfur-silicon flame retardant.

[0032] S4: The PC pellets were placed in a blast drying oven at 120°C for 10 hours, and the nitrogen-sulfur-silicon flame retardant and polytetrafluoroethylene powder were dried in a vacuum drying oven at 200°C for 6 hours. First, the masterbatch was prepared, and then the pellets were mixed evenly according to the mass ratio of PC, nitrogen-sulfur-silicon flame retardant and polytetrafluoroethylene of 100:8:3, and then extruded and granulated with a twin-screw extruder.

[0033] Embodiment 3

[0034] A method for preparing a highly heat-resistant, environmentally friendly, flame-retardant polycarbonate modified material, the specific preparation process is as follows:

[0035] S1: Add 9.28g of cyanuric chloride and 100mL of acetone to a three-necked flask with a mechanical stirring device, maintain the temperature of the system at -5-0°C, and stir until completely dissolved. Dissolve 6.92g of taurine and 3.10g of potassium hydroxide in N-methylpyrrolidone, and slowly drip into the above three-necked flask using a constant pressure dropping funnel. A large amount of precipitate will be produced during the reaction. The pH value is adjusted to 7-8 with a 2mol / L K2CO3 solution. After the reaction is completed, the intermediate 1 is obtained by filtering, washing, and drying.

[0036] S2: Add 6.05 g of 2'2-diamino-4'4-(9-fluorenyl)biphenol and 100 mL of acetone to a three-necked flask with a mechanical stirrer and a nitrogen protection device, maintain the temperature at 30-35°C, and stir until fully dissolved. Dissolve 15.58 g of intermediate 1 in N-methylpyrrolidone and slowly drip into the above solution using a constant pressure dropping funnel, adjust the pH value to 7-8 with a 2 mol / L K2CO3 solution, and after the reaction is completed, evaporate, filter and dry to obtain intermediate 2.

[0037] S3: 5.50g of 1,3-bis(3-aminopropyl)-1,1,3,3,-tetramethyldisiloxane, 5.55g of K2CO3, and ethanol were placed in a four-necked flask equipped with mechanical stirring, condensation reflux, and nitrogen protection. 15.37g of intermediate 2 was dissolved in N-methylpyrrolidone and added to the above solution in small amounts several times. The reaction temperature was 80-85°C. After the reaction was completed, evaporation, filtration, extraction, and evaporation were performed to finally obtain a nitrogen-sulfur-silicon flame retardant.

[0038] S4: The PC pellets were placed in a blast drying oven at 120°C for 10 hours, and the nitrogen-sulfur-silicon flame retardant and polytetrafluoroethylene powder were dried in a vacuum drying oven at 200°C for 6 hours. First, the masterbatch was prepared, and then the pellets were mixed evenly according to the mass ratio of PC, nitrogen-sulfur-silicon flame retardant and polytetrafluoroethylene being 100:10:5, and then extruded and granulated using a twin-screw extruder.

[0039] Comparative Example 1

[0040] The main difference from Example 3 is that it only contains polycarbonate resin pellets.

[0041] Comparative Example 1

[0042] The main difference from Example 3 is that the flame retardant is polyaminopropylphenylsilsesquioxane flame retardant, and the steps are: placing PC pellets in a blast drying oven at 120°C for 10 hours, and drying the polyaminopropylphenylsilsesquioxane flame retardant and polytetrafluoroethylene powder in a vacuum drying oven at 200°C for 6 hours. First, prepare a masterbatch, and then according to the mass ratio of PC, polyaminopropylphenylsilsesquioxane flame retardant and polytetrafluoroethylene being 100:10:5, mix the pellets evenly, extrude and granulate them with a twin-screw extruder.

[0043] Comparative Example 3

[0044] The main difference from Example 3 is that the flame retardant is a silicon-based sulfonate flame retardant, and the steps are: drying the PC pellets in a blast drying oven at 120°C for 10 hours, and drying the silicon-based sulfonate flame retardant and polytetrafluoroethylene powder in a vacuum drying oven at 200°C for 6 hours. First, prepare a master batch, and then according to the mass ratio of PC, silicon-based sulfonate flame retardant and polytetrafluoroethylene being 100:10:5, mix the pellets evenly, extrude and granulate them with a twin-screw extruder.

[0045] The materials obtained from the above-mentioned Examples 1 to 3 and Comparative Examples 1 to 3 were processed into standard test samples and subjected to performance tests. The specific test standards and test results are shown in Table 1 below:

[0046] Table 1

[0047]

[0048] As can be seen from the table above, the LOI value of pure PC is 27.0%, and the combustion grade is UL94 V-2. With the addition of flame retardant and polytetrafluoroethylene powder, the LOI value of the composite material is increased from 27% to 37.7%, and its combustion grade passes UL94 V-0. Its tensile length and elongation at break are also gradually enhanced, and the heat resistance temperature is also improved, indicating that the flame retardant containing nitrogen, sulfur and silicon has good heat resistance, mechanical properties and flame retardancy, and has important applications in the electronics field and the automotive industry.

[0049] In addition, when comparing Example 1 with Example 3, the flame retardant containing only polycarbonate does not reach the flame retardant V0 level;

[0050] Comparison of Example 2 with Example 3 shows that although the flame retardancy of the polyaminopropylphenylsilsesquioxane flame retardant can reach the flame retardant V0 level, its LOI value and heat resistance are lower than those of the nitrogen-sulfur-silicon flame retardant;

[0051] Comparative Example 3 Compared with Example 3, although the flame retardancy of the silicon-based sulfonate flame retardant can reach the flame retardancy V0 level, its LOI value and heat resistance are lower than those of the nitrogen-sulfur silicon flame retardant.

[0052] In the description of the specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0053] The above contents are merely examples and explanations of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the invention or exceed the scope defined by the claims, they shall all fall within the protection scope of the present invention.

Claims

1. A method for preparing a highly heat-resistant, environmentally friendly, flame-retardant polycarbonate modified material, characterized in that: The specific preparation process is as follows: S1: Add cyanuric chloride and acetone into a three-necked flask and stir until completely dissolved; dissolve taurine and potassium hydroxide in N-methylpyrrolidone, slowly drip into the above solution using a constant pressure dropping funnel, adjust the pH value with K2CO3 solution, and after the reaction is completed, filter, wash and dry to obtain intermediate 1; S2: Add 2'2-diamino-4'4-(9-fluorenyl)biphenol and acetone into a three-necked flask and stir until fully dissolved; dissolve intermediate 1 in N-methylpyrrolidone, slowly drip into the above solution using a constant pressure dropping funnel, adjust the pH value with K2CO3 solution, and after the reaction is completed, evaporate, filter and dry to obtain intermediate 2; S3: 1,3-bis(3-aminopropyl)-1,1,3,3,-tetramethyldisiloxane, K2CO3 and ethanol are placed in a four-necked flask, intermediate 2 is dissolved in N-methylpyrrolidone, and added to the above solution in small amounts and multiple times. After the reaction is completed, evaporation, filtration, extraction and evaporation are performed to finally obtain a nitrogen-sulfur-silicon flame retardant; S4: The PC pellets are placed in a blast drying oven for drying, the nitrogen-sulfur-silicon-containing flame retardant and the polytetrafluoroethylene powder are dried in a vacuum drying oven, the PC pellets, the nitrogen-sulfur-silicon-containing flame retardant and the polytetrafluoroethylene powder are mixed evenly according to the proportion, and then extruded and granulated by a twin-screw extruder.

2. The method for preparing a highly heat-resistant, environmentally friendly, flame-retardant polycarbonate modified material according to claim 1, characterized in that: In step S1, the ratio of cyanuric chloride, acetone, taurine and potassium hydroxide is 9.28 g:100 mL:6.92 g:3.10 g, and cyanuric chloride and acetone are dissolved at a temperature of -5-0°C, and the pH value is adjusted to 7-8.

3. The method for preparing a highly heat-resistant, environmentally friendly, flame-retardant polycarbonate modified material according to claim 1, characterized in that: In step S2, the ratio of 2'2-diamino-4'4-(9-fluorenyl)biphenol, acetone and intermediate 1 is 6.05g:100mL:15.58g, and 2'2-diamino-4'4-(9-fluorenyl)biphenol and acetone are dissolved at a temperature of 30-35°C under the protection of nitrogen, and the pH value is adjusted to 7-8.

4. The method for preparing a highly heat-resistant, environmentally friendly, flame-retardant polycarbonate modified material according to claim 1, characterized in that: In step S3, the ratio of the amount of 1,3-bis(3-aminopropyl)-1,1,3,3,-tetramethyldisiloxane, potassium carbonate and intermediate 2 is 5.50g:5.55g:15.37g, and 1,3-bis(3-aminopropyl)-1,1,3,3,-tetramethyldisiloxane, K2CO3, ethanol and intermediate 2 are reacted at a temperature of 80-85°C and under the protection of nitrogen.

5. The method for preparing a highly heat-resistant, environmentally friendly, flame-retardant polycarbonate modified material according to claim 1, characterized in that: The specific operation of step S4 is: placing the PC pellets in a 120° C. forced air drying oven for 10 hours, drying the nitrogen-sulfur-silicon-containing flame retardant and polytetrafluoroethylene powder in a 200° C. vacuum drying oven for 6 hours, and evenly mixing the PC pellets, the nitrogen-sulfur-silicon-containing flame retardant and the polytetrafluoroethylene powder in a mass ratio of 100:5-10:1-5, and then extruding and granulating them with a twin-screw extruder.

6. A highly heat-resistant, environmentally friendly, flame-retardant polycarbonate modified material, characterized in that: Prepared according to the preparation method according to any one of claims 1 to 5.

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