Highly flame-retardant polyether TPU material and preparation method therefor

Abstract

The present invention relates to the technical field of polymer materials, and in particular relates to a highly flame-retardant polyether TPU material, and a preparation method therefor. In the present invention, in the preparation of a modified polyether TPU, aminated nano-silica is added, which can cause the aminated nano-silica to be uniformly dispersed in the TPU matrix, to form physical crosslinking points, thereby enhancing the mechanical strength, modulus and wear resistance of the TPU. Nanoscale dispersion can significantly improve the overall mechanical properties of the material, and the addition of aminated nano-silica can improve the resilience, tear resistance and fatigue resistance of the TPU; the aminated nano-silica can shield ultraviolet radiation by means of surface properties thereof, thereby indirectly improving the ultraviolet aging resistance of the TPU, and enabling the TPU to maintain stable performance in humid environments; the amino groups on the surface of the aminated nano-silica have relatively high reactivity, and can be coupled with a variety of molecules and groups, providing a basis for subsequent functional modification of the TPU with flame retardants.

Description

A high flame-retardant polyether-type TPU material and its preparation method Technical Field

[0001] This invention relates to the field of polymer materials technology, specifically to a highly flame-retardant polyether-type TPU material and its preparation method. Background Technology

[0002] In recent years, with increasing global emphasis on environmental protection and fire safety, the flame-retardant properties of polymer materials have become a focus of industry attention. Polyurethane, or TPU, is a high-performance polymer material widely used in industrial, residential, medical, and military fields due to its wear resistance, aging resistance, and high resilience. However, the flammability of ordinary TPU materials limits their application in scenarios with higher safety requirements. The limiting oxygen index of traditional TPU materials is only 16%-18%, which means it will burn rapidly when exposed to fire and produce a large amount of toxic fumes, posing a significant safety hazard to users and the environment.

[0003] Polyether-based TPU, as an important branch of TPU materials, has shown great application potential in cables, wire harnesses, and other fields due to its excellent hydrolysis resistance and aging resistance. By combining flame retardants with polyether-based TPU, highly flame-retardant polyether-based TPU materials have been developed. These materials not only significantly improve the flame retardant properties of the materials but also maintain their original physical and chemical properties, providing safer and more reliable solutions for wire and cable, automotive electronics, and other fields. In conclusion, the development of a highly flame-retardant polyether-based TPU material can not only meet the market demand for high-performance flame-retardant materials but also promote the green and sustainable development of related industries. Summary of the Invention

[0004] In view of the above-mentioned shortcomings of the prior art, the present invention provides a high flame retardant polyether-type TPU material and its preparation method, which can effectively solve the problem of poor flame retardant performance of polyether-type TPU in the prior art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: A high flame-retardant polyether-type TPU material, wherein the high flame-retardant polyether-type TPU material is composed of the following components: modified polyether-type TPU, phosphorus-based flame retardant, dopamine-type flame retardant, and silane coupling agent KH-560; the modified polyether-type TPU is prepared from aminated nano-silica, phosphorus-based flame retardant, polyethylene glycol, toluene diisocyanate, and 1,4-butanediol; the phosphorus-based flame retardant is prepared from 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and p-hydroxybenzaldehyde; the dopamine-type flame retardant is prepared from nano-silica and dopamine hydrochloride.

[0006] Furthermore, the preparation method of the aminated nano silica is as follows: 1g of nano silica is dispersed in 300mL of anhydrous ethanol, ultrasonically dispersed at a frequency of 26kHz for 30min, and then 2mL of 3-aminopropyltriethoxysilane is added dropwise at a dropping rate of 2 drops / s. After ultrasonic dispersion at a frequency of 27kHz for 30min, the mixture is placed in an oil bath at 60℃ and stirred at a speed of 200r / min for 6h. After removing the filtrate by vacuum filtration, the mixture is washed 5 times with anhydrous ethanol and dried in a vacuum oven at 60℃ for 24h. The resulting product is called aminated nano silica.

[0007] Furthermore, the preparation method of the phosphorus-based flame retardant is as follows: Under nitrogen protection, 5g of bisphenol fluorene and 1mL of triethylamine are added to 50mL of dichloromethane, and stirred at 500r / min for 10min in a water bath at 10℃. Then, 1.5g of phenylphosphine dichloride is added and stirred at 200r / min for 10h. The resulting white solid is dried in an oven at 50℃ for 2h and then ground through a 200-mesh sieve. The obtained product is the phosphorus-based flame retardant.

[0008] Furthermore, the preparation steps of the modified polyether TPU are as follows: Step 1: Place 60g of polyethylene glycol under vacuum dehydration at a temperature of 110-120℃ and a vacuum degree of 133.3Pa for 2 hours. After cooling to 70℃, pour it into a flask and add 155g of toluene diisocyanate at a dropping rate of 1 drop / s under stirring. After the addition is completed, keep it at a constant temperature of 80℃ for 2 hours in a water bath. The result is recorded as the reaction component. Step 2: Add 0.2g of aminated nano-silica and 0.1g of phosphorus-based flame retardant to 30g of 1,4-butanediol. After ultrasonic dispersion, add it to the reaction component heated to 100℃ and under vigorous stirring. After the addition is completed, continue stirring for 10 minutes and pour it into a mold. Place it in an oven at 110℃ and cure for 10 hours. The result is the modified polyether TPU.

[0009] Furthermore, in step 1, the stirring speed is 200 r / min, and in step 2, the ultrasonic dispersion is performed at a frequency of 28 kHz for 30 min. In step 2, the stirring speed is 600 r / min.

[0010] Furthermore, the preparation steps of the phosphorus-based flame retardant are as follows: Step A: Weigh 13g of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and dissolve it in 100mL of dichloromethane. After stirring and dissolving, record it as the first component. Weigh 6g of p-hydroxybenzaldehyde and dissolve it in 50mL of dichloromethane. After ultrasonic dissolution, record it as the second component. Step B: Pour the second component into the first component and mix evenly. React under a water bath at 80℃ for 4 hours. After the reaction is completed, pour it into a beaker, seal it, and let it stand and air dry in layers. The result is the phosphorus-based flame retardant.

[0011] Furthermore, the stirring and dissolving method in step A is to stir at a speed of 500 r / min for 30 min, the ultrasonic dissolving method in step A is to ultrasonically disperse at a frequency of 28 kHz for 10 min, and the mixing and homogenization method in step B is to stir at a speed of 300 r / min for 5 min.

[0012] Furthermore, the preparation method of the dopamine-type flame retardant is as follows: Add 0.2g of nano-silica, 0.25g of dopamine hydrochloride and 0.4g of tris(hydroxymethyl)aminomethane to 200g of deionized water, mix thoroughly, add 10% sodium hydroxide solution to adjust the pH value to 9, disperse by ultrasonication, and then place under constant temperature of 28℃ for mechanical stirring for 8h. After centrifugation to remove the filtrate, rinse three times with deionized water, and dry to obtain the dopamine-type flame retardant.

[0013] Furthermore, in the preparation method of dopamine-type flame retardant, the thorough mixing operation is to stir at 300 r / min for 30 min, the ultrasonic dispersion operation is to ultrasonically disperse at a frequency of 23 kHz for 5 min, the mechanical stirring speed is 200 r / min, the centrifugation operation is to centrifuge at 6000 r / min for 5 min, and the drying operation is to dry in an oven at 55℃ for 3 h.

[0014] A method for preparing a high flame-retardant polyether-type TPU material, the method comprising the following steps: 100 parts by weight of modified polyether-type TPU is poured into a two-roll mill and milled for 2-3 minutes at front and rear roll temperatures of 110°C and 100°C respectively. 5-8 parts by weight of phosphorus-based flame retardant, 6-10 parts by weight of dopamine-type flame retardant and 1-2 parts by weight of silane coupling agent KH-560 are added and milling continues for 10 minutes. After forming a triangular package 10 times, the material is discharged. Finally, it is preheated on a flat vulcanizing machine at 170°C for 5 minutes, followed by hot pressing for 3 minutes and cold pressing for 2 minutes to demold. The resulting material is the high flame-retardant polyether-type TPU material.

[0015] This invention provides a high flame-retardant polyether-type TPU material and its preparation method. Compared with existing technologies, this invention has the following advantages: 1. In the preparation of modified polyether-type TPU, this invention adds aminated nano-silica, which can uniformly disperse the aminated nano-silica in the TPU matrix, forming physical cross-linking points, thereby enhancing the mechanical strength, modulus, and wear resistance of TPU. The nano-level dispersion can significantly improve the overall mechanical properties of the material. Moreover, the addition of aminated nano-silica can improve the resilience, tear resistance, and fatigue resistance of TPU. Secondly, aminated nano-silica can shield ultraviolet rays through its surface properties, thereby indirectly improving the UV aging resistance of TPU. The addition of aminated nano-silica can also enhance the hydrolysis resistance of TPU, enabling it to maintain stable performance in humid environments. Finally, the amino groups on the surface of aminated nano-silica have high reactivity and can couple with various molecules and groups, laying the foundation for subsequent functional modification of TPU using flame retardants.

[0016] 2. In this invention, a phosphorus-based flame retardant synthesized from bisphenol fluorene and phenylphosphine dichloride is added as a chain extender to the preparation of modified polyether TPU. This enables the prepared modified polyether TPU to have stable flame retardant properties. Moreover, the phosphorus-based flame retardant, as a chain extender, can participate in the polymerization reaction of TPU, thereby increasing the length and cross-linking degree of TPU molecular chains, and also improving the physical properties of TPU, such as tensile strength, tear strength, and abrasion resistance. Furthermore, the phosphorus-based flame retardant itself has high heat resistance and can maintain stable chemical properties at high temperatures, thereby improving the thermal stability of the modified polyether TPU.

[0017] 3. This invention adds a phosphorus-based flame retardant, a dopamine-based flame retardant, and a silane coupling agent KH-560 to modified polyether-type TPU. This allows the amino groups on the surface of the aminated nano-silica within the modified polyether-type TPU to be coupled and grafted with the phosphorus-based flame retardant, the dopamine-based flame retardant, and the silane coupling agent KH-560, respectively. This ensures that the phosphorus-based flame retardant and the dopamine-based flame retardant are stably dispersed within the modified polyether-type TPU molecules, resulting in a highly flame-retardant polyether-type TPU material with stable flame-retardant properties. The silane coupling agent KH-560 serves as... An excellent adhesion promoter can significantly improve the interfacial bonding force between fillers and TPU. Adding silane coupling agent KH-560 to modified polyether TPU can improve the dispersibility and wettability of phosphorus-based flame retardants and dopamine-based flame retardants in TPU, thereby improving the mechanical properties of the material such as tensile strength, flexural strength and interlaminar shear strength. Secondly, the dopamine molecules in the dopamine-based flame retardant can undergo a self-polymerization reaction under ultraviolet irradiation to form a stable protective layer, effectively blocking the destructive effect of ultraviolet rays and improving the weather resistance of the material. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0019] The present invention will be further described below with reference to embodiments.

[0020] Example 1 This example describes a high flame-retardant polyether-type TPU material, which is composed of the following components: modified polyether-type TPU, phosphorus-based flame retardant, dopamine-based flame retardant, and silane coupling agent KH-560. The modified polyether-type TPU is prepared from aminated nano-silica, phosphorus-based flame retardant, polyethylene glycol, toluene diisocyanate, and 1,4-butanediol. The aminated nano-silica is prepared by dispersing 1g of nano-silica in 300mL of anhydrous ethanol, ultrasonically dispersing at a frequency of 26kHz for 30min, and then adding 2mL at a dropping rate of 2 drops / s. 3-Aminopropyltriethoxysilane was ultrasonically dispersed at a frequency of 27 kHz for 30 min, then stirred at 200 r / min for 6 h in an oil bath at 60 °C. After removing the filtrate by vacuum filtration, the filtrate was washed 5 times with anhydrous ethanol and dried in a vacuum oven at 60 °C for 24 h. The resulting product was denoted as aminated nano-silica.

[0021] The preparation method of phosphorus-based flame retardant is as follows: Under nitrogen protection, 5g of bisphenol fluorene and 1mL of triethylamine are added to 50mL of dichloromethane. The mixture is stirred at 500r / min for 10min in a water bath at 10℃. Then, 1.5g of phenylphosphine dichloride is added and the mixture is stirred at 200r / min for 10h. The resulting white solid is dried in an oven at 50℃ for 2h and then ground through a 200-mesh sieve. The obtained product is the phosphorus-based flame retardant.

[0022] The preparation steps of modified polyether TPU are as follows: Step 1: Place 60g of polyethylene glycol under vacuum dehydration at 110℃ and 133.3Pa for 2 hours. After cooling to 70℃, pour it into a flask and add 155g of toluene diisocyanate at a dropping rate of 1 drop / s under stirring at 200r / min. After the addition is complete, keep it at a constant temperature of 80℃ for 2 hours. The result is recorded as the reaction component. Step 2: Add 0.2g of aminated nano-silica and 0.1g of phosphorus-based flame retardant to 30g of 1,4-butanediol. After ultrasonic dispersion at 28kHz for 30 minutes, add it to the reaction component heated to 100℃ and under vigorous stirring at 600r / min. After the addition is complete, continue stirring for 10 minutes and pour it into a mold. Place it in an oven at 110℃ and cure for 10 hours. The result is the modified polyether TPU.

[0023] The phosphorus-based flame retardant is prepared from 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and p-hydroxybenzaldehyde. The preparation steps of the phosphorus-based flame retardant are as follows: Step A: Weigh 13g of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and dissolve it in 100mL of dichloromethane. Stir at 500r / min for 30min and record it as the first component. Weigh 6g of p-hydroxybenzaldehyde and dissolve it in 50mL of dichloromethane. Disperse it ultrasonically at 28kHz for 10min and record it as the second component. Step B: Pour the second component into the first component and stir at 300r / min for 5min. React in a water bath at 80℃ for 4h. After the reaction is completed, pour it into a beaker, seal it, and let it stand to separate into layers and air dry. The result is the phosphorus-based flame retardant.

[0024] Dopamine-type flame retardants are prepared from nano-silica and dopamine hydrochloride. The preparation method of dopamine-type flame retardants is as follows: 0.2g of nano-silica, 0.25g of dopamine hydrochloride and 0.4g of tris(hydroxymethyl)aminomethane are added to 200g of deionized water. The mixture is stirred at 300r / min for 30min, and then a 10% sodium hydroxide solution is added dropwise to adjust the pH value to 9. The mixture is ultrasonically dispersed at a frequency of 23kHz for 5min, and then mechanically stirred at 200r / min for 8h under constant temperature conditions of 28℃. After centrifugation at 6000r / min for 5min to remove the filtrate, the mixture is washed 3 times with deionized water and dried in an oven at 55℃ for 3h. The resulting product is the dopamine-type flame retardant.

[0025] A method for preparing a high flame-retardant polyether-type TPU material includes the following steps: 100 parts by weight of modified polyether-type TPU is poured into a two-roll mill and milled for 2 minutes at front and rear roll temperatures of 110°C and 100°C, respectively. 5 parts by weight of phosphorus-based flame retardant, 6 parts by weight of dopamine-type flame retardant, and 1 part by weight of silane coupling agent KH-560 are added, and milling continues for 10 minutes. After forming a triangular package 10 times, the material is discharged. Finally, it is preheated on a flat vulcanizing machine at 170°C for 5 minutes, followed by hot pressing for 3 minutes, and then cold pressing for 2 minutes to demold. The resulting material is the high flame-retardant polyether-type TPU material.

[0026] Example 2 This example describes a high flame-retardant polyether-type TPU material, which is composed of the following components: modified polyether-type TPU, phosphorus-based flame retardant, dopamine-based flame retardant, and silane coupling agent KH-560. The modified polyether-type TPU is prepared from aminated nano-silica, phosphorus-based flame retardant, polyethylene glycol, toluene diisocyanate, and 1,4-butanediol. The aminated nano-silica is prepared by dispersing 1g of nano-silica in 300mL of anhydrous ethanol, ultrasonically dispersing at a frequency of 26kHz for 30min, and then adding 2mL at a dropping rate of 2 drops / s. 3-Aminopropyltriethoxysilane was ultrasonically dispersed at a frequency of 27 kHz for 30 min, then stirred at 200 r / min for 6 h in an oil bath at 60 °C. After removing the filtrate by vacuum filtration, the filtrate was washed 5 times with anhydrous ethanol and dried in a vacuum oven at 60 °C for 24 h. The resulting product was denoted as aminated nano-silica.

[0027] The preparation method of phosphorus-based flame retardant is as follows: Under nitrogen protection, 5g of bisphenol fluorene and 1mL of triethylamine are added to 50mL of dichloromethane. The mixture is stirred at 500r / min for 10min in a water bath at 10℃. Then, 1.5g of phenylphosphine dichloride is added and the mixture is stirred at 200r / min for 10h. The resulting white solid is dried in an oven at 50℃ for 2h and then ground through a 200-mesh sieve. The obtained product is the phosphorus-based flame retardant.

[0028] The preparation steps of modified polyether TPU are as follows: Step 1: Place 60g of polyethylene glycol under vacuum dehydration at 120℃ and 133.3Pa for 2 hours. After cooling to 70℃, pour it into a flask and add 155g of toluene diisocyanate at a dropping rate of 1 drop / s under stirring at 200r / min. After the addition is complete, keep it at a constant temperature of 80℃ for 2 hours. The result is recorded as the reaction component. Step 2: Add 0.2g of aminated nano-silica and 0.1g of phosphorus-based flame retardant to 30g of 1,4-butanediol. After ultrasonic dispersion at 28kHz for 30 minutes, add it to the reaction component heated to 100℃ and under vigorous stirring at 600r / min. After the addition is complete, continue stirring for 10 minutes and pour it into a mold. Place it in an oven at 110℃ and cure for 10 hours. The result is the modified polyether TPU.

[0029] The phosphorus-based flame retardant is prepared from 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and p-hydroxybenzaldehyde. The preparation steps of the phosphorus-based flame retardant are as follows: Step A: Weigh 13g of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and dissolve it in 100mL of dichloromethane. Stir at 500r / min for 30min and record it as the first component. Weigh 6g of p-hydroxybenzaldehyde and dissolve it in 50mL of dichloromethane. Disperse it ultrasonically at 28kHz for 10min and record it as the second component. Step B: Pour the second component into the first component and stir at 300r / min for 5min. React in a water bath at 80℃ for 4h. After the reaction is completed, pour it into a beaker, seal it, and let it stand to separate into layers and air dry. The result is the phosphorus-based flame retardant.

[0030] Dopamine-type flame retardants are prepared from nano-silica and dopamine hydrochloride. The preparation method of dopamine-type flame retardants is as follows: 0.2g of nano-silica, 0.25g of dopamine hydrochloride and 0.4g of tris(hydroxymethyl)aminomethane are added to 200g of deionized water. The mixture is stirred at 300r / min for 30min, and then a 10% sodium hydroxide solution is added dropwise to adjust the pH value to 9. The mixture is ultrasonically dispersed at a frequency of 23kHz for 5min, and then mechanically stirred at 200r / min for 8h under constant temperature conditions of 28℃. After centrifugation at 6000r / min for 5min to remove the filtrate, the mixture is washed 3 times with deionized water and dried in an oven at 55℃ for 3h. The resulting product is the dopamine-type flame retardant.

[0031] A method for preparing a high flame-retardant polyether-type TPU material includes the following steps: 100 parts by weight of modified polyether-type TPU is poured into a two-roll mill and milled for 3 minutes at front and rear roll temperatures of 110°C and 100°C, respectively. 8 parts by weight of phosphorus-based flame retardant, 10 parts by weight of dopamine-type flame retardant, and 2 parts by weight of silane coupling agent KH-560 are added, and milling continues for 10 minutes. After forming a triangular package 10 times, the material is discharged. Finally, it is preheated on a flat vulcanizing machine at 170°C for 5 minutes, followed by hot pressing for 3 minutes, and then cold pressing for 2 minutes to demold. The resulting material is the high flame-retardant polyether-type TPU material.

[0032] Example 3 This example describes a high flame-retardant polyether-type TPU material, which is composed of the following components: modified polyether-type TPU, phosphorus-based flame retardant, dopamine-based flame retardant, and silane coupling agent KH-560. The modified polyether-type TPU is prepared from aminated nano-silica, phosphorus-based flame retardant, polyethylene glycol, toluene diisocyanate, and 1,4-butanediol. The aminated nano-silica is prepared by dispersing 1g of nano-silica in 300mL of anhydrous ethanol, ultrasonically dispersing at a frequency of 26kHz for 30min, and then adding 2mL at a dropping rate of 2 drops / s. 3-Aminopropyltriethoxysilane was ultrasonically dispersed at a frequency of 27 kHz for 30 min, then stirred at 200 r / min for 6 h in an oil bath at 60 °C. After removing the filtrate by vacuum filtration, the filtrate was washed 5 times with anhydrous ethanol and dried in a vacuum oven at 60 °C for 24 h. The resulting product was denoted as aminated nano-silica.

[0033] The preparation method of phosphorus-based flame retardant is as follows: Under nitrogen protection, 5g of bisphenol fluorene and 1mL of triethylamine are added to 50mL of dichloromethane. The mixture is stirred at 500r / min for 10min in a water bath at 10℃. Then, 1.5g of phenylphosphine dichloride is added and the mixture is stirred at 200r / min for 10h. The resulting white solid is dried in an oven at 50℃ for 2h and then ground through a 200-mesh sieve. The obtained product is the phosphorus-based flame retardant.

[0034] The preparation steps of modified polyether TPU are as follows: Step 1: Place 60g of polyethylene glycol under vacuum dehydration at 115℃ and 133.3Pa for 2 hours. After cooling to 70℃, pour it into a flask and add 155g of toluene diisocyanate at a dropping rate of 1 drop / s under stirring at 200r / min. After the addition is complete, keep it at a constant temperature of 80℃ for 2 hours. The result is recorded as the reaction component. Step 2: Add 0.2g of aminated nano-silica and 0.1g of phosphorus-based flame retardant to 30g of 1,4-butanediol. After ultrasonic dispersion at 28kHz for 30 minutes, add it to the reaction component heated to 100℃ and under vigorous stirring at 600r / min. After the addition is complete, continue stirring for 10 minutes and pour it into a mold. Place it in an oven at 110℃ and cure for 10 hours. The result is the modified polyether TPU.

[0035] The phosphorus-based flame retardant is prepared from 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and p-hydroxybenzaldehyde. The preparation steps of the phosphorus-based flame retardant are as follows: Step A: Weigh 13g of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and dissolve it in 100mL of dichloromethane. Stir at 500r / min for 30min and record it as the first component. Weigh 6g of p-hydroxybenzaldehyde and dissolve it in 50mL of dichloromethane. Disperse it ultrasonically at 28kHz for 10min and record it as the second component. Step B: Pour the second component into the first component and stir at 300r / min for 5min. React in a water bath at 80℃ for 4h. After the reaction is completed, pour it into a beaker, seal it, and let it stand to separate into layers and air dry. The result is the phosphorus-based flame retardant.

[0036] Dopamine-type flame retardants are prepared from nano-silica and dopamine hydrochloride. The preparation method of dopamine-type flame retardants is as follows: 0.2g of nano-silica, 0.25g of dopamine hydrochloride and 0.4g of tris(hydroxymethyl)aminomethane are added to 200g of deionized water. The mixture is stirred at 300r / min for 30min, and then a 10% sodium hydroxide solution is added dropwise to adjust the pH value to 9. The mixture is ultrasonically dispersed at a frequency of 23kHz for 5min, and then mechanically stirred at 200r / min for 8h under constant temperature conditions of 28℃. After centrifugation at 6000r / min for 5min to remove the filtrate, the mixture is washed 3 times with deionized water and dried in an oven at 55℃ for 3h. The resulting product is the dopamine-type flame retardant.

[0037] A method for preparing a high flame-retardant polyether-type TPU material includes the following steps: 100 parts by weight of modified polyether-type TPU is poured into a two-roll mill and milled for 3 minutes at front and rear roll temperatures of 110°C and 100°C, respectively. 6 parts by weight of phosphorus-based flame retardant, 8 parts by weight of dopamine-type flame retardant, and 2 parts by weight of silane coupling agent KH-560 are added, and milling continues for 10 minutes. After forming a triangular package 10 times, the material is discharged. Finally, it is preheated on a flat vulcanizing machine at 170°C for 5 minutes, followed by hot pressing for 3 minutes, and then cold pressing for 2 minutes to demold. The resulting material is the high flame-retardant polyether-type TPU material.

[0038] Comparative Example 1: The highly flame-retardant polyether-type TPU material and its preparation method provided in this comparative example are generally the same as those in Example 1. The main difference is that the modified polyether-type TPU in Example 1 is replaced with polyether-type TPU.

[0039] Comparative Example 2: The highly flame-retardant polyether-type TPU material and its preparation method provided in this comparative example are generally the same as those in Example 1. The main difference is that the phosphorus flame retardant in Example 1 is replaced with 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide in this comparative example 2.

[0040] Comparative Example 3: The highly flame-retardant polyether-type TPU material and its preparation method provided in this comparative example are generally the same as those in Example 1. The main difference is that the dopamine-type flame retardant in Example 1 is replaced with nano-silica in this comparative example 3.

[0041] Performance testing was conducted on the highly flame-retardant polyether-type TPU materials prepared in Examples 1-3 and Comparative Examples 1-3, labeled as Example 1, Example 2, Example 3, Comparative Example 1, Comparative Example 2, and Comparative Example 3, respectively. The performance of Examples 1-3 and Comparative Examples 1-3 was then tested. Specific testing methods and items are as follows: 1. The tensile strength and elongation at break of Examples 1-3 and Comparative Examples 1-3 were tested according to GB / T528-1998, and the data are recorded in the table below; 2. The limiting oxygen index of Examples 1-3 and Comparative Examples 1-3 was tested according to GB / T2406-2009, and the data are recorded in the table below; 3. A vertical burning test was conducted on Examples 1-3 and Comparative Examples 1-3 according to ANSI / UL-94-1985, with sample dimensions of 127mm × 12mm × 3mm. The data are recorded in the table below.

[0042] The data in the table above shows that the mechanical properties of the high flame-retardant polyether TPU materials in Examples 1-3 are significantly better than those in Comparative Example 1. This indicates that adding aminated nano-silica and phosphorus-based flame retardants to the high flame-retardant polyether TPU materials can improve the mechanical properties of TPU. Moreover, the limiting oxygen index of the high flame-retardant polyether TPU materials in Examples 1-3 is significantly higher than that in Comparative Examples 1-3, indicating that the addition of phosphorus-based flame retardants and dopamine-based flame retardants can improve the flame-retardant properties of TPU. In summary, the high flame-retardant polyether TPU materials prepared by this invention have excellent market application prospects.

[0043] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0044] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high flame-retardant polyether-type TPU material, characterized in that, The high flame-retardant polyether-type TPU material is composed of the following components: modified polyether-type TPU, phosphorus-based flame retardant, dopamine-type flame retardant, and silane coupling agent KH-560; The modified polyether-type TPU is prepared from amino-modified nano-silica, phosphorus-based flame retardant, polyethylene glycol, toluene diisocyanate and 1,4-butanediol as raw materials; The phosphorus-based flame retardant is prepared from 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and p-hydroxybenzaldehyde; the dopamine-type flame retardant is prepared from nano-silica and dopamine hydrochloride.

2. The high flame-retardant polyether-type TPU material according to claim 1, characterized in that, The preparation method of the aminated nano-silica is as follows: 1 g of nano-silica was dispersed in 300 mL of anhydrous ethanol and ultrasonically dispersed at a frequency of 26 kHz for 30 min. Then, 2 mL of 3-aminopropyltriethoxysilane was added dropwise at a rate of 2 drops / s and ultrasonically dispersed at a frequency of 27 kHz for 30 min. The mixture was then placed in an oil bath at 60 °C and stirred at a speed of 200 r / min for 6 h. After removing the filtrate by vacuum filtration, the mixture was washed 5 times with anhydrous ethanol and dried in a vacuum oven at 60 °C for 24 h. The resulting product was denoted as aminated nano-silica.

3. The high flame-retardant polyether-type TPU material according to claim 1, characterized in that, The preparation method of the phosphorus-based flame retardant is as follows: Under nitrogen protection, 5g of bisphenol fluorene and 1mL of triethylamine were added to 50mL of dichloromethane. The mixture was stirred at 500r / min for 10min in a water bath at 10℃. Then, 1.5g of phenylphosphine dichloride was added and the mixture was stirred at 200r / min for 10h. The resulting white solid was dried in an oven at 50℃ for 2h and then ground through a 200-mesh sieve. The obtained product is the phosphorus-based flame retardant.

4. The high flame-retardant polyether-type TPU material according to claim 1, characterized in that, The preparation steps of the modified polyether-type TPU are as follows: Step 1: Place 60g of polyethylene glycol under vacuum dehydration at 110-120℃ and 133.3Pa for 2 hours. After cooling to 70℃, pour it into a flask and add 155g of toluene diisocyanate at a dropping rate of 1 drop / s under stirring. After the addition is complete, keep it at a constant temperature of 80℃ in a water bath for 2 hours. The result is recorded as the reaction component. Step 2: Add 0.2g of aminated nano-silica and 0.1g of phosphorus-based flame retardant to 30g of 1,4-butanediol. After ultrasonic dispersion, add the mixture to the reaction components heated to 100℃ and subjected to vigorous stirring. After the addition is complete, continue stirring for 10 minutes, then pour the mixture into a mold and place it in an oven at 110℃ for 10 hours to cure. The resulting product is modified polyether TPU.

5. The high flame-retardant polyether-type TPU material according to claim 4, characterized in that, In step 1, the stirring speed is 200 r / min. In step 2, the ultrasonic dispersion is carried out at a frequency of 28 kHz for 30 min. In step 2, the stirring speed is 600 r / min.

6. The high flame-retardant polyether-type TPU material according to claim 1, characterized in that, The preparation steps of the phosphorus-based flame retardant are as follows: Step A: Weigh 13g of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide and dissolve it in 100mL of dichloromethane. After stirring and dissolving, record it as the first component. Weigh 6g of p-hydroxybenzaldehyde and dissolve it in 50mL of dichloromethane. After sonicating and dissolving, record it as the second component. Step B: Pour the second component into the first component and mix well. React in a water bath at 80°C for 4 hours. After the reaction is complete, pour the mixture into a beaker, seal it, and let it stand to air dry in layers. The resulting product is a phosphorus-based flame retardant.

7. The high flame-retardant polyether-type TPU material according to claim 6, characterized in that, The stirring and dissolving method in step A is to stir at a speed of 500 r / min for 30 min. The ultrasonic dissolving method in step A is to ultrasonically disperse at a frequency of 28 kHz for 10 min. The mixing and homogenization method in step B is to stir at a speed of 300 r / min for 5 min.

8. The high flame-retardant polyether-type TPU material according to claim 1, characterized in that, The preparation method of the dopamine-type flame retardant is as follows: Add 0.2g of nano-silica, 0.25g of dopamine hydrochloride and 0.4g of tris(hydroxymethyl)aminomethane to 200g of deionized water. After thorough mixing, add 10% sodium hydroxide solution to adjust the pH to 9. After ultrasonic dispersion, place the mixture at a constant temperature of 28℃ and stir mechanically for 8 hours. After centrifugation to remove the filtrate, rinse three times with deionized water and dry. The resulting product is the dopamine-type flame retardant.

9. The high flame-retardant polyether-type TPU material according to claim 8, characterized in that, In the preparation method of dopamine-type flame retardant, the thorough mixing operation is to stir at 300 r / min for 30 min, the ultrasonic dispersion operation is to ultrasonically disperse at a frequency of 23 kHz for 5 min, the mechanical stirring speed is 200 r / min, the centrifugation operation is to centrifuge at 6000 r / min for 5 min, and the drying operation is to dry in an oven at 55℃ for 3 h.

10. A method for preparing a high flame-retardant polyether-type TPU material according to any one of claims 1-9, characterized in that, The preparation method includes the following steps: 100 parts by weight of modified polyether TPU are poured into a two-roll mill and milled for 2-3 minutes at front and rear roll temperatures of 110°C and 100°C, respectively. Then, 5-8 parts by weight of phosphorus-based flame retardant, 6-10 parts by weight of dopamine-based flame retardant, and 1-2 parts by weight of silane coupling agent KH-560 are added and milling continues for 10 minutes. After forming a triangular package 10 times, the material is discharged. Finally, it is preheated on a flat vulcanizing machine at 170°C for 5 minutes, followed by hot pressing for 3 minutes and cold pressing for 2 minutes to demold. The resulting material is high flame retardant polyether TPU material.

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