Preparation method and application of high-temperature-resistant flame-retardant fireproof blanket

Abstract

The invention relates to the technical field of fireproof and flame-retardant materials, and discloses a preparation method and application of a high-temperature-resistant and flame-retardant fireproof blanket, and the high-temperature-resistant and flame-retardant fireproof blanket is formed by weaving high-temperature-resistant and flame-retardant fireproof polyester fibers; the polyimide flame retardant and polyethylene glycol terephthalate are subjected to blending melt spinning, and the high-temperature-resistant flame-retardant fireproof polyester fiber is obtained. A molecular chain of the polyimide flame retardant contains an ester group structural unit, and the polyimide flame retardant has good compatibility with polyethylene glycol terephthalate, so that the polyimide flame retardant is uniformly dispersed in polyester fibers, the mechanical properties of the fibers are improved, and higher breaking strength and elongation at break are shown. Meanwhile, the limit oxygen index of the polyester fiber is increased, the initial thermal weight loss temperature and the high-temperature mass residual rate are obviously increased, and the polyester fiber shows good flame retardance and high-temperature resistance.

Description

Technical Field

[0001] The invention relates to the technical field of fireproof and flame-retardant materials, in particular to a preparation method and application of a high-temperature resistant and flame-retardant fireproof blanket. Background Art

[0002] Fire-retardant textiles are widely used in fire safety, special protective equipment and other fields. Polyester fibers are mainly made from polyethylene terephthalate. Its fibers and textiles have good mechanical properties, wear resistance and UV resistance, and are widely used. However, the flame retardancy of polyester fibers is poor, which limits their practical application in fire-retardant textiles.

[0003] The main chain of polyimide contains an imide ring, which is an organic polymer material with high mechanical strength, good flame retardancy and strong high temperature resistance. It is widely used in polymer materials such as PET, epoxy resin, polyurethane, etc. Patent CN102947389B discloses a transparent polyimide-polyester composition, its preparation method and products, using polyetherimide, polyetherimide sulfone, polyethylene terephthalate, phenolic stabilizer, phosphorus stabilizer, etc. as raw materials, and the obtained polyimide-polyester composition has good transparency and physical properties. However, the polyester composition does not have good flame retardancy and cannot meet the practical application in flame retardant and fireproof fiber textiles. Summary of the invention

[0004] The technical problem solved by the invention is to provide a polyester fiber with high temperature resistance and flame retardancy and a fireproof blanket thereof.

[0005] The technical solution provided by the present invention is: the high temperature resistant and flame retardant fire blanket is woven from high temperature resistant and flame retardant fireproof polyester fibers; the preparation method of the fireproof polyester fibers is: (1) Add a solvent, terephthalic acid (phthalic anhydride) ester, and di(4-aminophenyl)phenylphosphonate in a ratio of (6-8) L:1 mol:(1-1.05) mol into a reaction container, stir and react at 20-30°C for 10-15 hours, pour the solution onto a clean glass plate surface, place it in a heating box, and heat treat it at 100-110°C for 1.5-2 hours, 150-160°C for 1-1.5 hours, 200-210°C for 2-2.5 hours, 240-250°C for 2-2.5 hours, and 280-300°C for 1-1.5 hours, cool, and grind to obtain a polyimide flame retardant.

[0006] (2) 100 parts by weight of polyethylene terephthalate and 5-25 parts by weight of a polyimide flame retardant are melt-extruded in an extruder; then, the fibers are spun in a melt spinning machine and stretched in a drawing machine to obtain a fire-resistant polyester fiber.

[0007] Preferably, the solvent is N,N-dimethylformamide or N,N-dimethylacetamide.

[0008] Preferably, the preparation method of terephthalic acid (phthalic anhydride) ester is as follows: toluene, terephthaloyl chloride, 4-hydroxyphthalic anhydride, and pyridine in a ratio of (5-6) L: 1 mol: (2-2.2) mol: (2.6-3.8) mol are added to a reaction container, stirred at 20-25°C for 18-24 hours, rotary evaporated, washed with water, methanol, and chloroform in turn, and dried to obtain terephthalic acid (phthalic anhydride) ester. The reaction formula is as follows: .

[0009] Preferably, the preparation method of phenylphosphonic acid di(4-aminophenyl) ester is as follows: tetrahydrofuran, phenylphosphonic acid dichloride, 4-nitrophenol, and triethylamine in a ratio of (3-4) L: 1 mol: (2-2.4) mol: (2-2.2) mol are added to a reaction container, heated to 40-50°C in a nitrogen atmosphere, reacted for 2-3 hours, rotary evaporated, washed with water, added to ethanol, added stannous chloride, concentrated hydrochloric acid with a mass fraction of 35-37%, heated to 75-80°C, condensed and refluxed for 3-4 hours, rotary evaporated, washed with water, and the product was recrystallized in ethanol to obtain phenylphosphonic acid di(4-aminophenyl) ester. The reaction formula is as follows: .

[0010] Preferably, the high temperature resistant and flame retardant fire blanket is used in flame retardant and fireproof materials.

[0011] The technical effect of the present invention is: a polyimide flame retardant is obtained by polymerization reaction using a novel terephthalic acid (phthalic anhydride) ester as a dianhydride monomer and phenylphosphonic acid di (4-aminophenyl) ester as a dianhydride monomer. Then, after being blended with polyethylene terephthalate for melt spinning, a high temperature resistant and flame retardant fireproof polyester fiber and a fireproof blanket thereof are obtained. Since the molecular chain of the polyimide flame retardant contains an ester structural unit, it has good compatibility with polyethylene terephthalate, so that the polyimide flame retardant is evenly dispersed in the polyester fiber, which is beneficial to improving the mechanical properties of the fiber and showing higher breaking strength and breaking elongation. In addition, the polyimide has strong high temperature resistance, and contains a phosphate flame retardant group, which forms a nitrogen-phosphorus flame retardant with the nitrogen-containing heterocycle in the molecular chain, thereby improving the limiting oxygen index of the polyester fiber, and the initial thermal weight loss temperature and high temperature mass residual rate of the fiber are significantly improved, showing good flame retardancy and high temperature resistance. DETAILED DESCRIPTION

[0012] The technical solution described in this application is further explained below in conjunction with specific implementation methods, but the present application is not limited thereto.

[0013] Example 1 (1) Add 25 mL of toluene, 5 mmol of terephthaloyl chloride, 10 mmol of 4-hydroxyphthalic anhydride, and 15 mmol of pyridine to a reaction vessel, stir and react at 25°C for 18 hours, rotary evaporate, wash with water, methanol, and chloroform in sequence, and dry to obtain terephthalic acid (phthalic anhydride) ester.

[0014] (2) Add 30 mL of tetrahydrofuran, 10 mmol of phenylphosphonic acid dichloride, 20 mmol of 4-nitrophenol and 20 mmol of triethylamine to a reaction vessel, heat to 40°C in a nitrogen atmosphere, react for 3 h, rotary evaporate, wash with water, add the product to 70 mL of ethanol, add 11 g of stannous chloride and 10 mL of 35% concentrated hydrochloric acid, heat to 75°C, condense and reflux for 4 h, rotary evaporate, wash with water, and recrystallize the product from ethanol to obtain di(4-aminophenyl)phenylphosphonate.

[0015] (3) Add 70 mL of N,N-dimethylformamide, 10 mmol of terephthalic acid (phthalic anhydride) ester and 10 mmol of di(4-aminophenyl)phenylphosphonate into a reaction container, stir and react at 20°C for 12 h, pour the solution onto a clean glass plate, place in a heating box, heat treat at 100°C for 1.5 h, 150°C for 1.5 h, 210°C for 2 h, 250°C for 2 h and 290°C for 1.5 h, cool and grind to obtain a polyimide flame retardant.

[0016] (4) 100 g of polyethylene terephthalate and 5 g of polyimide flame retardant are melt-extruded in an extruder with a melting section temperature of 280°C; then spinning is carried out in a melt spinning machine with screw zones 1-4 having temperatures of 275°C, 285°C, 295°C, and 295°C, respectively; then drawing is carried out in a drawing machine with a drawing ratio of 3 times to obtain a fire-resistant polyester fiber.

[0017] Example 2 (1) Add 30 mL of toluene, 5 mmol of terephthaloyl chloride, 11 mmol of 4-hydroxyphthalic anhydride, and 19 mmol of pyridine to a reaction vessel, stir and react at 25°C for 18 hours, rotary evaporate, wash with water, methanol, and chloroform in sequence, and dry to obtain terephthalic acid (phthalic anhydride) ester.

[0018] (2) Add 40 mL of tetrahydrofuran, 10 mmol of phenylphosphonyl dichloride, 22 mmol of 4-nitrophenol and 20 mmol of triethylamine to a reaction vessel, heat to 50°C in a nitrogen atmosphere, react for 2 h, rotary evaporate, wash with water, add the product to 60 mL of ethanol, add 8 g of stannous chloride and 6 mL of 37% concentrated hydrochloric acid, heat to 80°C, condense and reflux for 3 h, rotary evaporate, wash with water, and recrystallize the product from ethanol to obtain di(4-aminophenyl)phenylphosphonate.

[0019] (3) Add 80 mL of N,N-dimethylformamide, 10 mmol of terephthalic acid (phthalic anhydride) ester and 10.5 mmol of di(4-aminophenyl)phenylphosphonate into a reaction container, stir and react at 30°C for 10 h, pour the solution onto a clean glass plate, place it in a heating box, and heat treat it at 110°C for 2 h, 160°C for 1 h, 200°C for 2 h, 240°C for 2.5 h, and 280°C for 1.5 h, cool it, and grind it to obtain a polyimide flame retardant.

[0020] (4) 100 g of polyethylene terephthalate and 10 g of polyimide flame retardant are melt-extruded in an extruder with a melting section temperature of 280°C; then spinning is carried out in a melt spinning machine with screw zones 1-4 having temperatures of 275°C, 285°C, 295°C, and 295°C, respectively; then drawing is carried out in a drawing machine with a drawing ratio of 3 times to obtain a fire-resistant polyester fiber.

[0021] Example 3 (1) Add 30 mL of toluene, 5 mmol of terephthaloyl chloride, 10 mmol of 4-hydroxyphthalic anhydride, and 13 mmol of pyridine to a reaction vessel, stir and react at 20°C for 24 hours, rotary evaporate, wash with water, methanol, and chloroform in sequence, and dry to obtain terephthalic acid (phthalic anhydride) ester.

[0022] (2) Add 40 mL of tetrahydrofuran, 10 mmol of phenylphosphonic acid dichloride, 24 mmol of 4-nitrophenol and 22 mmol of triethylamine to a reaction vessel, heat to 45°C in a nitrogen atmosphere, react for 3 h, rotary evaporate, wash with water, add the product to 70 mL of ethanol, add 9 g of stannous chloride and 10 mL of 35% concentrated hydrochloric acid, heat to 75°C, condense and reflux for 4 h, rotary evaporate, wash with water, and recrystallize the product from ethanol to obtain di(4-aminophenyl)phenylphosphonate.

[0023] (3) Add 60 mL of N,N-dimethylacetamide, 10 mmol of terephthalic acid (phthalic anhydride) ester and 10 mmol of di(4-aminophenyl)phenylphosphonate into a reaction container, stir and react at 20°C for 15 h, pour the solution onto a clean glass plate, place it in a heating box, and heat treat it at 110°C for 1.5 h, 160°C for 1 h, 200°C for 2.5 h, 250°C for 2.5 h, and 300°C for 1 h, cool it, and grind it to obtain a polyimide flame retardant.

[0024] (4) 100 g of polyethylene terephthalate and 15 g of polyimide flame retardant are melt-extruded in an extruder with a melting section temperature of 280°C; then spinning is carried out in a melt spinning machine with screw zones 1-4 having temperatures of 275°C, 285°C, 295°C, and 295°C, respectively; then drawing is carried out through a drawing machine with a drawing ratio of 3 times to obtain a fire-resistant polyester fiber.

[0025] Example 4 (1) 100 g of polyethylene terephthalate and 20 g of polyimide flame retardant (prepared in Example 1) were melt-extruded in an extruder at a melting temperature of 280°C; then, spinning was performed in a melt spinning machine at screw zones 1-4 at temperatures of 275°C, 285°C, 295°C, and 295°C, respectively; then, the fibers were stretched in a stretching machine at a stretching ratio of 3 times to obtain a fire-resistant polyester fiber.

[0026] Example 5 (1) 100 g of polyethylene terephthalate and 25 g of polyimide flame retardant (prepared in Example 1) were melt-extruded in an extruder at a melting temperature of 280°C; then spun in a melt spinning machine at screw zones 1-4 at temperatures of 275°C, 285°C, 295°C, and 295°C, respectively; then stretched in a stretching machine at a stretching ratio of 3 times to obtain a fire-resistant polyester fiber.

[0027] Comparative Example 1 (1) 100 g of polyethylene terephthalate is melt-extruded in an extruder with a melting zone temperature of 280°C; then it is spun in a melt spinning machine with screw zone temperatures of 275°C, 285°C, 295°C, and 295°C, respectively; then it is stretched in a stretching machine with a stretching ratio of 3 times to obtain a fire-resistant polyester fiber.

[0028] Comparative Example 2 (1) Add 70 mL of N,N-dimethylformamide, 10 mmol of 4,4'-biphenyl ether dianhydride and 10 mmol of di(4-aminophenyl)phenylphosphonate into a reaction container, stir and react at 20°C for 12 h, pour the solution onto a clean glass plate, place it in a heating box, and heat treat it at 100°C for 1.5 h, 150°C for 1.5 h, 210°C for 2 h, 250°C for 2 h and 290°C for 1.5 h, cool and grind to obtain a polyimide flame retardant.

[0029] (2) 100 g of polyethylene terephthalate and 5 g of polyimide flame retardant are melt-extruded in an extruder with a melting section temperature of 280°C; then spinning is carried out in a melt spinning machine with screw zones 1-4 having temperatures of 275°C, 285°C, 295°C, and 295°C, respectively; then drawing is carried out in a drawing machine with a drawing ratio of 3 times to obtain a fire-resistant polyester fiber.

[0030] Comparative Example 3 (1) Add 70 mL of N,N-dimethylformamide, 10 mmol of terephthalic acid (phthalic anhydride) ester, and 10 mmol of 4,4'-diaminobiphenyl into a reaction container, stir and react at 20°C for 12 h, pour the solution onto the surface of a clean glass plate, place it in a heating box, and heat treat it at 100°C for 1.5 h, 150°C for 1.5 h, 210°C for 2 h, 250°C for 2 h, and 290°C for 1.5 h, cool it, and grind it to obtain polyimide.

[0031] (2) 100 g of polyethylene terephthalate and 5 g of polyimide are melt-extruded in an extruder with a melting zone temperature of 280°C; then they are spun in a melt spinning machine with screw zone temperatures of 1-4 being 275°C, 285°C, 295°C, and 295°C, respectively; then they are stretched in a stretching machine with a stretching ratio of 3 times to obtain a fire-resistant polyester fiber.

[0032] The oxygen index of polyester fiber is tested according to GB / T 5454-1997 standard.

[0033] The thermal properties were tested by a thermogravimetric analyzer in a nitrogen atmosphere with a heating rate of 10°C / min and a test temperature of 20-800°C.

[0034] The mechanical properties are tested according to GB / T 14337-2022 standard.

[0035] Table 1

[0036] It can be seen from the above table that the limiting oxygen index of the polyester fiber in Comparative Example 1 is only 20.8%, the flame retardancy is very poor, and the initial thermal weight loss temperature and high-temperature mass residual rate are low, the high-temperature resistance is poor, the breaking strength and breaking elongation are low, and the mechanical properties are poor.

[0037] In Examples 1-5, polyimide flame retardant is added. Polyimide has strong high temperature resistance and contains phosphate flame retardant groups. It forms nitrogen-phosphorus flame retardant with nitrogen-containing heterocycles in the molecular chain, improves the limiting oxygen index of polyester fiber, and significantly improves the initial thermal weight loss temperature and high temperature mass residual rate, showing good flame retardancy and high temperature resistance. In addition, the molecular chain of polyimide flame retardant contains ester structural units, which has good compatibility with polyethylene terephthalate. After blending and melt spinning, the polyimide flame retardant is evenly dispersed in the polyester fiber, which is beneficial to improve the mechanical properties of the fiber, showing higher breaking strength and breaking elongation.

[0038] In Comparative Example 2, 4,4'-biphenyl ether dianhydride and di(4-aminophenyl)phenylphosphonate were polymerized to obtain a polyimide flame retardant that does not contain an ester structural unit and has poor compatibility with polyethylene terephthalate, which is not conducive to improving the mechanical properties of polyester fibers, and the elongation at break is significantly reduced.

[0039] In Comparative Example 3, terephthalic acid (phthalic anhydride) ester and 4,4'-diaminobiphenyl are used for polymerization reaction. The obtained polyimide does not contain phosphate flame retardant groups, has poor flame retardant effect on polyester fibers, and has a low limiting oxygen index.

[0040] The above description of the embodiments is to facilitate the understanding and use of the present application by those skilled in the art, and those skilled in the art to which the present application belongs may also make appropriate changes and modifications to the above implementations. Therefore, the present application is not limited to the specific implementations disclosed and described above, and some modifications and changes to the present application should also fall within the scope of protection of the claims of the present application.

Claims

1. A method for preparing a high temperature resistant and flame retardant fire blanket, characterized in that: The high temperature resistant and flame retardant fire blanket is woven from high temperature resistant and flame retardant fireproof polyester fibers; the preparation method of the fireproof polyester fibers is as follows: (1) Add a solvent, terephthalic acid (phthalic anhydride) ester, and bis(4-aminophenyl)phenylphosphonate to a reaction container, stir and react at 20-30°C for 10-15h, pour the solution on the surface of a clean glass plate, place it in a heating box, and heat treat it at 100-110°C for 1.5-2h, 150-160°C for 1-1.5h, 200-210°C for 2-2.5h, 240-250°C for 2-2.5h, and 280-300°C for 1-1.5h, cool, and grind to obtain a polyimide flame retardant; (2) 100 parts by weight of polyethylene terephthalate and 5-25 parts by weight of a polyimide flame retardant are melt-extruded in an extruder; then, the fibers are spun in a melt spinning machine and stretched in a drawing machine to obtain a fire-resistant polyester fiber.

2. The method for preparing a high temperature resistant and flame retardant fire blanket according to claim 1, characterized in that: In the above (1), the ratio of solvent, terephthalic acid (phthalic anhydride) ester and di(4-aminophenyl)phenylphosphonate is (6-8) L:1 mol:(1-1.05) mol.

3. The method for preparing a high temperature resistant and flame retardant fire blanket according to claim 2, characterized in that: The solvent is N,N-dimethylformamide or N,N-dimethylacetamide.

4. The method for preparing a high temperature resistant and flame retardant fire blanket according to claim 2, characterized in that: The preparation method of terephthalic acid (phthalic anhydride) ester is as follows: toluene, terephthaloyl chloride, 4-hydroxyphthalic anhydride and pyridine are added into a reaction container, stirred and reacted at 20-25° C. for 18-24 hours, rotary evaporated, washed with water, methanol and chloroform in sequence, and dried to obtain terephthalic acid (phthalic anhydride) ester.

5. The method for preparing a high temperature resistant and flame retardant fire blanket according to claim 4, characterized in that: The ratio of toluene, terephthaloyl chloride, 4-hydroxyphthalic anhydride and pyridine is (5-6) mol: 1 mol: (2-2.2) mol: (2.6-3.8) mol.

6. The method for preparing a high temperature resistant and flame retardant fire blanket according to claim 2, characterized in that: The preparation method of bis(4-aminophenyl)phenylphosphonate is as follows: tetrahydrofuran, phenylphosphonyl dichloride, 4-nitrophenol and triethylamine are added into a reaction container, heated to 40-50°C in a nitrogen atmosphere, reacted for 2-3h, rotary evaporated, washed with water, added the product into ethanol, added stannous chloride and concentrated hydrochloric acid, heated to 75-80°C, condensed and refluxed for 3-4h, rotary evaporated, washed with water, and the product was recrystallized in ethanol to obtain bis(4-aminophenyl)phenylphosphonate.

7. The method for preparing a high temperature resistant and flame retardant fire blanket according to claim 6, characterized in that: The ratio of tetrahydrofuran, phenylphosphonic acid dichloride, 4-nitrophenol and triethylamine is (3-4) mol: 1 mol: (2-2.4) mol: (2-2.2) mol.

8. The method for preparing a high temperature resistant and flame retardant fire blanket according to claim 6, characterized in that: The mass fraction of the concentrated hydrochloric acid is 35-37%.

9. Use of a high temperature resistant and flame retardant fire blanket obtained by the preparation method according to any one of claims 1 to 8 in flame retardant and fireproof materials.

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