Fireproof insulating PC material with high bending strength and preparation method thereof

Abstract

The invention relates to the technical field of polycarbonate, and discloses a fireproof insulating PC material with high bending strength and a preparation method thereof, the fireproof insulating PC material comprises 100 parts by weight of polycarbonate and 2-10 parts by weight of a cross-linked polysiloxane modifier; the cross-linked polysiloxane modifier contains groups such as hydroxyl, imino and the like, and has the effects of forming hydrogen bonds with ester groups of polycarbonate and the like, so that the cross-linked polysiloxane modifier and the polycarbonate have good compatibility, meanwhile, the modifier forms a flexible polysiloxane cross-linked particle structure and has a good toughening effect on the polycarbonate, and the impact strength and the bending strength of the material are improved. And the cross-linked polysiloxane modifier contains sulfonate, triazine and polysiloxane flame-retardant structures, so that the flame-retardant and fireproof performance of the PC material is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of polycarbonate, in particular to a fireproof insulating PC material with high bending strength and a preparation method thereof. Background Art

[0002] Polycarbonate has excellent electrical insulation, good dimensional stability, and high heat resistance, and is widely used. Although polycarbonate has certain flame retardant properties, it is still difficult to meet the requirements for applications in the field of fire prevention and flame retardancy. Therefore, it is necessary to improve the flame retardant properties of polycarbonate. Common flame retardants for polycarbonate include sulfonate flame retardants, nitrogen-phosphorus flame retardants, and silicon-based flame retardants.

[0003] Polysiloxane is a silicone polymer with high flexibility, excellent flame retardancy, excellent insulation, and strong water resistance. It is widely used as a flame retardant and toughening agent. Patent Publication No. CN116444970B discloses a phosphaphenanthrene / siloxane dual-based macromolecule flame-retardant and toughened polycarbonate material. Using macromolecules containing phosphaphenanthrene and siloxane structures as flame retardants and toughening agents improves the flame retardancy and mechanical properties of polycarbonate. Furthermore, since silicone polymers such as polysiloxane are not compatible with polycarbonate, improving their compatibility can improve the material's properties, such as flexural strength. Summary of the Invention

[0004] In view of the shortcomings of the existing technology, the present invention provides a fireproof insulation PC material with high bending strength and a preparation method thereof, which solves the problems of low bending strength and poor flame retardancy of polycarbonate materials.

[0005] To solve the above technical problems, the present invention adopts a technical solution: a fireproof insulating PC material with high bending strength and a preparation method thereof, wherein the fireproof insulating PC material comprises 100 parts by weight of polycarbonate and 2-10 parts by weight of a cross-linked polysiloxane modifier. The preparation method comprises:

[0006] (1) Allylamino polysiloxane and 2,4-bis(sodium 4-hydroxybenzenesulfonate)-6-allylamino-1,3,5-triazine are added to N,N-dimethylformamide, and after stirring, azobisisobutyronitrile is added dropwise in a nitrogen atmosphere. After stirring for reaction, the solution is poured into ethanol, filtered, washed with water and ethanol, and dried to obtain a cross-linked polysiloxane modifier.

[0007] (2) The polycarbonate and the cross-linked polysiloxane modifier are mixed, extruded in a twin-screw extruder, and pelletized to obtain a fireproof insulating PC material with high bending strength.

[0008] Preferably, the reaction temperature in (1) is 65-80°C and the reaction time is 8-12h.

[0009] Preferably, the mass ratio of allylaminopolysiloxane, 2,4-bis(sodium 4-hydroxybenzenesulfonate)-6-allylamino-1,3,5-triazine and azobisisobutyronitrile in (1) is 100:(60-150):(0.5-1.3).

[0010] Preferably, the temperature of each section of the twin-screw extruder in (2) is 220-265° C., and the screw speed is 150-300 r / min.

[0011] Preferably, the preparation method of allylamino polysiloxane is as follows: add glycidoxy-terminated polydimethylsiloxane and allylamine to isopropyl alcohol, heat to 40-70°C, react for 6-12 hours, add the product after vacuum distillation to water, stir, let it stand to separate, remove the aqueous phase, and dry the oil phase to remove water to obtain allylamino polysiloxane. The reaction formula is:

[0012]

[0013] Preferably, the mass ratio of glycidoxy-terminated polydimethylsiloxane to allylamine is 100:(6.8-8.4).

[0014] Preferably, the preparation method of 2,4-bis(sodium 4-hydroxybenzenesulfonate)-6-allylamino-1,3,5-triazine is as follows: 2,4-bis(sodium 4-hydroxybenzenesulfonate)-6-chloro-1,3,5-triazine and allylamine are added to 1,4-dioxane, stirred, and then a sodium carbonate aqueous solution is added. The mixture is heated to 70-85°C, reacted for 7-10 hours, and the product is washed with acetone after vacuum distillation and dried to obtain 2,4-bis(sodium 4-hydroxybenzenesulfonate)-6-allylamino-1,3,5-triazine. The reaction formula is:

[0015]

[0016] Preferably, the molar ratio of 2,4-bis(sodium 4-hydroxybenzenesulfonate)-6-chloro-1,3,5-triazine, allylamine and sodium carbonate is 1:(1-1.4):(1.2-1.8).

[0017] (3) Beneficial technical effects: The present invention uses a polysiloxane containing a double-terminal allyl group as a cross-linking agent, reacts with 2,4-bis(sodium 4-hydroxybenzenesulfonate)-6-allylamino-1,3,5-triazine to obtain a cross-linked polysiloxane modifier, and then modifies polycarbonate to obtain a fire-resistant insulating PC material with high bending strength. The cross-linked polysiloxane modifier contains hydroxyl groups, imino groups and other groups, which form hydrogen bonds with the ester groups of polycarbonate, making the two have good compatibility. At the same time, the modifier forms a flexible polysiloxane cross-linked particle structure, which has a good toughening effect on polycarbonate and improves the impact strength and bending strength of the material.

[0018] The cross-linked polysiloxane modifier of the present invention contains a large number of sulfonate groups. During combustion, it pyrolyzes to produce sulfur dioxide and other substances, which promote the isomerization and cross-linking of polycarbonate to form carbon. At the same time, the triazine groups and polysiloxane form a nitrogen-silicon flame retardant, further improving the flame retardancy and fire resistance of the PC material and significantly increasing the limiting oxygen index. Polycarbonate itself has excellent electrical insulation properties, and polysiloxane also has a high resistivity, which gives the PC material excellent insulation properties. DETAILED DESCRIPTION

[0019] The following is a clear and complete description of the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0020] The following polycarbonate, model LG-DOW PC, was sourced from Shenzhen Maite Plastic Products Co., Ltd. Glycidoxy-terminated polydimethylsiloxane, with a molecular weight of approximately 2000, was sourced from Wuhan Kemik Biopharmaceutical Technology Co., Ltd. Double-terminated aminopropyl polysiloxane, with a molecular weight of approximately 2000, was sourced from Wuhan Kemik Biopharmaceutical Technology Co., Ltd. Polyethylene glycol diacrylate, with a molecular weight of approximately 2100, was sourced from Guangdong Fangxin Biotechnology Co., Ltd.

[0021] 2,4-bis(sodium 4-hydroxybenzenesulfonate)-6-chloro-1,3,5-triazine was prepared according to the method in the article "Synthesis of water-soluble triazine derivatives and their application in cellulose modification" published in the journal "New Chemical Materials" in December 2015, Vol. 43, No. 12.

[0022] To 350 mL of acetone, 100 mmol of cyanuric chloride and 200 mmol of sodium 4-hydroxybenzenesulfonate were added, and after stirring, 350 mL of an aqueous solution containing 200 mmol of sodium hydroxide was added. The mixture was reacted in an ice-water bath for 2 h, then heated to 40 ° C and reacted for 5 h. After filtering, the filter cake was washed with acetone and dried to obtain 2,4-bis(sodium 4-hydroxybenzenesulfonate)-6-chloro-1,3,5-triazine, the structural formula of which is

[0023] Example 1

[0024] (1) Add 200 g of glycidoxy-terminated polydimethylsiloxane and 16.8 g of allylamine to 1 L of isopropanol, heat to 40°C, and stir to react for 12 h. After vacuum distillation, add the product to water, stir, and allow to stand for stratification. Remove the aqueous phase, and dry the oil phase to remove water to obtain allylamino polysiloxane.

[0025] (2) Add 150 mmol of 2,4-bis(sodium 4-hydroxybenzenesulfonate)-6-chloro-1,3,5-triazine and 150 mmol of allylamine to 800 mL of 1,4-dioxane, stir, add 110 mL of an aqueous solution containing 270 mmol of sodium carbonate, heat to 70 °C, stir and react for 7 h, distill under reduced pressure, wash the product with acetone, and dry it to obtain 2,4-bis(sodium 4-hydroxybenzenesulfonate)-6-allylamino-1,3,5-triazine.

[0026] (3) Add 200 g of allylamino polysiloxane and 120 g of 2,4-bis(sodium 4-hydroxybenzenesulfonate)-6-allylamino-1,3,5-triazine to 2.5 L of N,N-dimethylformamide, stir, and then dropwise add 1 g of azobisisobutyronitrile in a nitrogen atmosphere. Heat to 70 ° C. and stir to react for 8 h. Pour the solution into ethanol, filter, wash with water and ethanol, and dry to obtain a cross-linked polysiloxane modifier.

[0027] (4) 5 kg of polycarbonate and 100 g of a cross-linked polysiloxane modifier were mixed and extruded in a twin-screw extruder at temperatures of 220° C., 240° C., 255° C., 265° C., 265° C., and 260° C., with a screw speed of 200 r / min; pelletized to obtain a fireproof insulating PC material with high flexural strength.

[0028] Example 2

[0029] (1) Add 200 g of glycidoxy-terminated polydimethylsiloxane and 13.6 g of allylamine to 0.8 L of isopropanol, heat to 70°C, and stir to react for 6 h. After vacuum distillation, add the product to water, stir, and allow to stand for stratification. Remove the aqueous phase, and dry the oil phase to remove water to obtain allylamino polysiloxane.

[0030] (2) Add 150 mmol of 2,4-bis(sodium 4-hydroxybenzenesulfonate)-6-chloro-1,3,5-triazine and 240 mmol of allylamine to 900 mL of 1,4-dioxane, stir, add 70 mL of an aqueous solution containing 180 mmol of sodium carbonate, heat to 85°C, stir and react for 10 hours, distill under reduced pressure, wash the product with acetone, and dry it to obtain 2,4-bis(sodium 4-hydroxybenzenesulfonate)-6-allylamino-1,3,5-triazine.

[0031] (3) Add 200 g of allylamino polysiloxane and 240 g of 2,4-bis(sodium 4-hydroxybenzenesulfonate)-6-allylamino-1,3,5-triazine to 3 L of N,N-dimethylformamide, stir, and then add 2 g of azobisisobutyronitrile dropwise in a nitrogen atmosphere. Heat to 65 ° C. and stir to react for 12 h. Pour the solution into ethanol, filter, wash with water and ethanol, and dry to obtain a cross-linked polysiloxane modifier.

[0032] (4) 5 kg of polycarbonate and 200 g of a cross-linked polysiloxane modifier were mixed and extruded in a twin-screw extruder at temperatures of 220°C, 240°C, 255°C, 265°C, 265°C, and 260°C, with a screw speed of 150 r / min; pelletized to obtain a fireproof insulating PC material with high bending strength.

[0033] Example 3

[0034] (1) To 3 L of N,N-dimethylformamide, 200 g of allylaminopolysiloxane (prepared according to the method of Example 1) and 300 g of 2,4-bis(sodium 4-hydroxybenzenesulfonate)-6-allylamino-1,3,5-triazine (prepared according to the method of Example 1) were added. After stirring, 2.6 g of azobisisobutyronitrile was added dropwise in a nitrogen atmosphere. The mixture was heated to 65° C. and stirred for 12 h. The solution was poured into ethanol, filtered, washed with water and ethanol, and dried to obtain a cross-linked polysiloxane modifier.

[0035] (2) 5 kg of polycarbonate and 350 g of a cross-linked polysiloxane modifier were mixed and extruded in a twin-screw extruder at temperatures of 220°C, 240°C, 255°C, 265°C, 265°C, and 260°C, with a screw speed of 300 r / min; pelletized to obtain a fireproof insulating PC material with high flexural strength.

[0036] Example 4

[0037] (1) To 2.5 L of N,N-dimethylformamide, 200 g of allylaminopolysiloxane (prepared according to the method of Example 1) and 180 g of 2,4-bis(sodium 4-hydroxybenzenesulfonate)-6-allylamino-1,3,5-triazine (prepared according to the method of Example 1) were added. After stirring, 1.5 g of azobisisobutyronitrile was added dropwise in a nitrogen atmosphere. The mixture was heated to 80° C. and stirred for 10 h. The solution was poured into ethanol, filtered, washed with water and ethanol, and dried to obtain a cross-linked polysiloxane modifier.

[0038] (2) 5 kg of polycarbonate and 500 g of a cross-linked polysiloxane modifier were mixed and extruded in a twin-screw extruder at temperatures of 220° C., 240° C., 255° C., 265° C., 265° C., and 260° C., with a screw speed of 200 r / min; pelletized to obtain a fireproof insulating PC material with high flexural strength.

[0039] Comparative Example 1: The difference between this comparative example and Example 1 is that no cross-linked polysiloxane modifier is added.

[0040] (1) 5 kg of polycarbonate was extruded in a twin-screw extruder at temperatures of 220°C, 240°C, 255°C, 265°C, 265°C, and 260°C in each section and at a screw speed of 200 r / min; pelletization was performed to obtain PC material.

[0041] Comparative Example 2: The difference between this comparative example and Example 1 is that styrene is used to replace 2,4-bis(sodium 4-hydroxybenzenesulfonate)-6-allylamino-1,3,5-triazine in the preparation of the cross-linked polysiloxane modifier.

[0042] (1) Add 200 g of allylamino polysiloxane and 120 g of styrene to 2.5 L of N,N-dimethylformamide, stir, and then dropwise add 1 g of azobisisobutyronitrile in a nitrogen atmosphere. Heat to 70 ° C. and stir for 8 h. Pour the solution into ethanol, filter, wash with water and ethanol, and dry to obtain a cross-linked polysiloxane modifier.

[0043] (2) 5 kg of polycarbonate and 100 g of a cross-linked polysiloxane modifier were mixed and extruded in a twin-screw extruder at temperatures of 220°C, 240°C, 255°C, 265°C, 265°C, and 260°C, with a screw speed of 200 r / min; pelletization was performed to obtain a PC material.

[0044] Comparative Example 3: The difference between this comparative example and Example 1 is that, in preparing the cross-linking modifier, double-terminal acrylamidopropyl polysiloxane is used instead of allylamino polysiloxane.

[0045] (1) Bi-terminal acrylamidopropyl polysiloxane was prepared according to the method of the article "Synthesis of terminal acrylamide polysiloxane and its modification of polyacrylate" published in the journal "Journal of Textile Research" in October 2014, Vol. 35, No. 10. 200 g of bi-terminal aminopropyl polysiloxane and 33 g of potassium carbonate were added to 70 mL of dichloromethane. 30 mL of a dichloromethane solution containing 21.6 g of acryloyl chloride was added dropwise in an ice-water bath. The mixture was heated to 35°C and stirred for 3 h. The mixture was extracted and washed with 5% sodium bicarbonate solution, water, and saturated sodium chloride solution in sequence. The dichloromethane organic phase was dried over anhydrous sodium sulfate and the dichloromethane was removed by vacuum distillation to obtain bi-terminal acrylamidopropyl polysiloxane.

[0046] (2) Add 200 g of double-ended acrylamidopropyl polysiloxane and 120 g of 2,4-bis(sodium 4-hydroxybenzenesulfonate)-6-allylamino-1,3,5-triazine to 2.5 L of N,N-dimethylformamide, stir, and then dropwise add 1 g of azobisisobutyronitrile in a nitrogen atmosphere. Heat to 70 ° C. and stir to react for 8 h. Pour the solution into ethanol, filter, wash with water and ethanol, and dry to obtain a cross-linked polysiloxane modifier.

[0047] (3) 5 kg of polycarbonate and 100 g of a cross-linked polysiloxane modifier were mixed and extruded in a twin-screw extruder at temperatures of 220° C., 240° C., 255° C., 265° C., 265° C., and 260° C., with a screw speed of 200 r / min; pelletized to obtain a fireproof insulating PC material with high flexural strength.

[0048] Comparative Example 4: The difference between this comparative example and Example 1 is that polyethylene glycol diacrylate is used to prepare the crosslinking modifier instead of allylamino polysiloxane.

[0049] (1) Add 200 g of polyethylene glycol diacrylate and 120 g of 2,4-bis(sodium 4-hydroxybenzenesulfonate)-6-allylamino-1,3,5-triazine to 2.5 L of N,N-dimethylformamide, stir, and then dropwise add 1 g of azobisisobutyronitrile in a nitrogen atmosphere. Heat to 70°C and stir for 8 h. Pour the solution into ethanol, filter, wash with water and ethanol, and dry to obtain a crosslinking modifier.

[0050] (2) 5 kg of polycarbonate and 100 g of a cross-linking modifier were mixed and extruded in a twin-screw extruder at temperatures of 220°C, 240°C, 255°C, 265°C, 265°C, and 260°C in each section and at a screw speed of 200 r / min; pelletization was performed to obtain a PC material.

[0051] Flame retardancy is tested according to GB / T 2406.1-2008. Flexural strength is tested according to GB / T 9341-2008. Impact strength is tested according to GB / T 1843-2008.

[0052] Table 1 Properties of PC materials

[0053]

[0054] The polycarbonate (PC) material of Comparative Example 1 has a low limiting oxygen index, low flexural strength and impact strength, and poor flame retardancy and mechanical strength. Each example incorporates a cross-linked polysiloxane modifier, which contains groups such as hydroxyl and imino groups, and forms hydrogen bonds with the ester groups of the polycarbonate, thereby improving the compatibility between the modifier and the polycarbonate. The modifier also forms a flexible polysiloxane cross-linked particle structure, which has a good toughening effect on the polycarbonate and improves the impact strength and flexural strength of the material. Furthermore, the modifier contains a large number of sulfonate groups, which pyrolyze during combustion to generate substances such as sulfur dioxide, which can promote the isomerization and cross-linking of the polycarbonate into carbon. At the same time, the triazine groups and the polysiloxane form a nitrogen silicon flame retardant, further improving the flame retardancy and fire resistance of the PC material and significantly improving the limiting oxygen index.

[0055] In Comparative Example 2, styrene is used instead of 2,4-bis(sodium 4-hydroxybenzenesulfonate)-6-allylamino-1,3,5-triazine. The resulting cross-linked polysiloxane modifier does not contain flame retardant groups such as sulfonate groups and triazine groups, which is not conducive to improving the flame retardancy of polycarbonate and results in a lower limiting oxygen index.

[0056] In Comparative Example 3, double-ended acrylamide propyl polysiloxane (free of hydroxyl and imino groups) was used instead of allylamino polysiloxane. The prepared cross-linked polysiloxane modifier did not contain hydroxyl and imino groups, had low hydrogen bonding force with polycarbonate, and had poor compatibility, resulting in poor toughening effect of the cross-linked polysiloxane modifier and low flexural strength and impact strength of the PC material.

[0057] Comparative Example 4 uses polyethylene glycol diacrylate instead of allylamino polysiloxane. The prepared modifier does not contain a polysiloxane structure, and the material has a low limiting oxygen index, flexural strength, and impact strength.

[0058] The above description is only an implementation method of the present application and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A fireproof insulation PC material with high bending strength, characterized in that: The fireproof insulating PC material comprises 100 parts by weight of polycarbonate and 2-10 parts by weight of a cross-linked polysiloxane modifier; The preparation method of the cross-linked polysiloxane modifier comprises the following steps: adding allylamino polysiloxane and 2,4-bis(sodium 4-hydroxybenzenesulfonate)-6-allylamino-1,3,5-triazine to N,N-dimethylformamide, stirring, dropwise adding azobisisobutyronitrile in a nitrogen atmosphere, stirring for reaction, pouring the solution into ethanol, filtering, washing, and drying to obtain the cross-linked polysiloxane modifier.

2. The fireproof insulating PC material with high bending strength according to claim 1, characterized in that: The reaction temperature is 65-80° C., and the reaction time is 8-12 hours.

3. The fireproof insulating PC material with high bending strength according to claim 1, characterized in that: The mass ratio of the allylamino polysiloxane, 2,4-bis(sodium 4-hydroxybenzenesulfonate)-6-allylamino-1,3,5-triazine and azobisisobutyronitrile is 100:(60-150):(0.5-1.3).

4. The fireproof insulating PC material with high bending strength according to claim 1, characterized in that: The preparation method of the allylamino polysiloxane comprises the following steps: adding glycidoxy-terminated polydimethylsiloxane and allylamine to isopropyl alcohol, heating to 40-70° C., reacting for 6-12 hours, adding the product after reduced pressure distillation to water, stirring, standing and separating, removing the aqueous phase, and drying the oil phase to obtain the allylamino polysiloxane.

5. The fireproof insulating PC material with high bending strength according to claim 4, characterized in that: The mass ratio of the glycidoxy-terminated polydimethylsiloxane to allylamine is 100:(6.8-8.4).

6. The fireproof insulating PC material with high bending strength according to claim 1, characterized in that: The preparation method of 2,4-bis(sodium 4-hydroxybenzenesulfonate)-6-allylamino-1,3,5-triazine comprises: adding 2,4-bis(sodium 4-hydroxybenzenesulfonate)-6-chloro-1,3,5-triazine and allylamine to 1,4-dioxane, stirring, adding a sodium carbonate aqueous solution, heating to 70-85° C., reacting for 7-10 hours, distilling under reduced pressure, washing the product with acetone, and drying to obtain 2,4-bis(sodium 4-hydroxybenzenesulfonate)-6-allylamino-1,3,5-triazine.

7. The fireproof insulating PC material with high bending strength according to claim 6, characterized in that: In the preparation method of 2,4-bis(sodium 4-hydroxybenzenesulfonate)-6-allylamino-1,3,5-triazine, the molar ratio of 2,4-bis(sodium 4-hydroxybenzenesulfonate)-6-chloro-1,3,5-triazine, allylamine and sodium carbonate is 1:(1-1.4):(1.2-1.8).

8. A method for preparing a fireproof insulating PC material with high bending strength according to any one of claims 1 to 7, characterized in that: The preparation method comprises: mixing polycarbonate and a cross-linked polysiloxane modifier, extruding the mixture in a twin-screw extruder, and pelletizing the mixture to obtain a fireproof insulation PC material with high bending strength.

9. The method for preparing a fireproof insulating PC material with high bending strength according to claim 8, characterized in that: The temperature of each section of the twin-screw extruder is 220-265° C., and the screw speed is 150-300 r / min.

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