Preparation method and application of high-efficiency smoke-suppressing and attenuated hybrid material

Abstract

The application discloses a preparation method and application of a high-efficiency smoke-reducing and virulence-reducing hybrid material. The formula composition of a traditional smoke-reducing and virulence-reducing material is abandoned, different structures of aluminum oxide are used as carriers, active component nickel oxide is loaded as the high-efficiency smoke-reducing and virulence-reducing hybrid material, and scientific interface regulation is carried out, so that the synergistic effect between the active component and the carrier is achieved, and thus the barrier effect and the catalytic effect are fully exerted. When the material is used in a processing process of thermoplastic polyurethane, good smoke-reducing, virulence-reducing and flame-retardant effects are achieved.

Description

Technical Field

[0001] This invention belongs to the field of polymer high-filler systems, specifically relating to a method for preparing a highly efficient smoke-suppressing and toxic-reducing hybrid material and its application. The addition of this highly efficient smoke-suppressing and toxic-reducing hybrid material comprehensively reduces the toxicity of the smoke from the composite material, achieving excellent smoke suppression, toxicity reduction, and flame retardant effects. Background Technology

[0002] Polymer materials are a class of high-molecular-weight macromolecular compounds used to prepare various materials and products. However, due to the flammability of most polymer materials, the frequency of fire accidents caused by them is constantly increasing. Among them, thermoplastic polyurethane (TPU) is a widely used polymer material. Its excellent elasticity, abrasion resistance, and corrosion resistance make it widely used in various fields, such as sports shoes, car seats, and medical supplies. However, TPU releases a large amount of smoke and harmful gases during processing and use. Therefore, improving the smoke suppression performance of TPU is crucial for ensuring the safety of production sites. Currently, methods to improve the smoke suppression performance of TPU mainly include adding smoke suppressants and modifying the material structure. Adding smoke suppressants can effectively reduce the smoke and harmful gases produced when TPU burns, with halogen-free smoke suppressants receiving increasing attention. Simultaneously, modifying the microstructure and morphology of TPU materials is also an important way to improve its smoke suppression performance. In the future, developing environmentally friendly and efficient TPU smoke suppression technologies will be a research hotspot, and more environmentally friendly and efficient methods will continue to be explored, with widespread applications in fields such as intelligent manufacturing and sustainable development.

[0003] To ensure personnel safety and environmental hygiene, improving the smoke suppression performance of TPU has become an important research direction. In related technical fields, numerous patent applications have involved technologies and methods for TPU smoke suppression. Some patents provide methods for improving TPU smoke suppression performance by adding smoke suppressants, such as layered titanium carbide-molybdenum trioxide hybrid flame retardants (CN111849145A), functionalized graphene surface nitrogen-doped flame retardants (CN109988411A), and aluminum hypophosphite hybrid flame retardants (CN107312199A). These technologies aim to achieve TPU smoke suppression targets by adding specific compounds or increasing the proportion of special components in the material. Other patents consider improving TPU smoke suppression performance from the material structure itself. For example, reducing TPU combustion smoke generation by adding intumescent flame-retardant polypropylene and TPU composite materials (CN104072977A), or modifying TPU with ceramics to improve its smoke suppression performance (CN107286636A). However, the above work has many shortcomings. For example, the material preparation process is complex (requiring surface modification and pretreatment of TPU) and involves the use of organic solvents. Furthermore, while the prepared composite materials exhibit good flame retardancy, their smoke suppression and toxicity reduction effects are generally poor. Therefore, designing a highly efficient smoke suppression and toxicity reduction hybrid material for flame retardancy and smoke suppression of TPU materials is particularly important. Summary of the Invention

[0004] This invention addresses the shortcomings in the field by providing a method for preparing a highly efficient smoke-suppressing and toxic-reducing hybrid material and its application. The smoke-suppressing and toxic-reducing hybrid material of this invention possesses properties such as high efficiency in smoke suppression, toxicity reduction, flame retardancy, and environmental friendliness. When used in the processing of thermoplastic polyurethane, it achieves excellent smoke suppression, toxicity reduction, and flame retardant effects.

[0005] The present invention discloses a method for preparing a highly efficient smoke-suppressing and toxicity-reducing hybrid material, which uses alumina with different structures as a carrier and loads nickel oxide, an active component, as the highly efficient smoke-suppressing and toxicity-reducing hybrid material. The method specifically includes the following steps:

[0006] Step 1: First, synthesize alumina nanoparticles, alumina nanosheets, and alumina nanospheres as carriers for smoke-suppressing and toxicity-reducing hybrid materials;

[0007] Step 2: Then, the alumina support is uniformly dispersed in n-hexane, and a completely dissolved nickel nitrate aqueous solution is added dropwise to the system under stirring. After the addition is complete, stirring and mixing are continued for a certain period of time to complete the loading of the active component.

[0008] Step 3: Next, place the mixed solution obtained in Step 2 into a forced-air drying oven for drying. After drying, calcine it at high temperature in a muffle furnace to obtain a high-efficiency smoke-suppressing and toxicity-reducing hybrid material.

[0009] Furthermore, in the high-efficiency smoke-suppressing and toxicity-reducing hybrid material, the active center nickel oxide accounts for 10 wt% of the total mass.

[0010] In step 1, the alumina nanoparticles are prepared by co-precipitation method and their size is in the range of 50-100 nm; the alumina nanosheets are prepared by hydrothermal method and their size is in the range of 5-30 μm; the alumina nanospheres are prepared by template method and their size is in the range of 200-500 nm.

[0011] In step 2, the mixing and stirring rate is 300 rpm, and the stirring time is 30-60 min; the concentration of the nickel nitrate aqueous solution is 0.1 mol / L, and the nickel loading is 10%.

[0012] In step 3, the drying temperature is 80-120℃ and the drying time is 6-12h; the calcination temperature is 400-600℃ and the calcination time is 6-10h.

[0013] The application of the high-efficiency smoke-suppressing and toxicity-reducing hybrid material of the present invention is to add the smoke-suppressing and toxicity-reducing hybrid material as an additive to thermoplastic polyurethane to improve the flame retardant and smoke-suppressing properties of the composite material.

[0014] Furthermore, when the smoke-suppressing and toxicity-reducing hybrid material is added as an additive to thermoplastic polyurethane, the composite material can be constructed using a solvent method.

[0015] Furthermore, the amount of the smoke-suppressing and toxicity-reducing hybrid material added is 1-3 wt% of the total mass of the composite material, such as 1 wt%, 2 wt%, or 3 wt%, with the remainder being thermoplastic polyurethane elastomer.

[0016] The beneficial effects of this invention are reflected in:

[0017] 1. This invention abandons the traditional formulation of smoke-suppressing and toxicity-reducing materials, and uses catalyst impregnation preparation technology to prepare highly efficient smoke-suppressing and toxicity-reducing agents with different structures. Through scientific interface control, the metal-carrier interaction between the active component nickel and the carrier alumina is achieved, so that the effects of the active component and the carrier are fully exerted. When used to prepare polyurethane composite materials, it achieves excellent flame retardant and smoke-suppressing effects.

[0018] 2. This invention utilizes catalyst impregnation technology to prepare highly efficient smoke-suppressing and toxicity-reducing hybrid materials with different structures. The composite materials are prepared via a solvent method, using readily available raw materials, a short process route, and controllable processes, making it suitable for industrial production. When used in the processing of thermoplastic polyurethane elastomers, it can achieve flame retardancy and smoke suppression, while being safe and environmentally friendly, reducing environmental pollution.

[0019] 3. The preparation process of this invention is simple to operate, green, low in production cost, simple in process, high in efficiency, highly controllable, free of "three wastes" pollution, low in equipment investment, and convenient to use. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of the smoke-suppressing and toxicity-reducing hybrid material of the present invention.

[0021] Figure 2 The images show the XRD patterns of smoke suppressants with different structures in the embodiments of the present invention.

[0022] Figure 3 These are SEM images of smoke suppressants with different structures in the embodiments of the present invention. Wherein a and d are smoke suppressants with alumina nanoparticles as carriers, b and e are smoke suppressants with alumina nanosheets as carriers, and c and f are smoke suppressants with alumina nanospheres as carriers.

[0023] Figure 4 These are cone calorimeter curves of the material with different addition amounts in embodiments of the present invention. Wherein, a is the heat release rate curve of the composite material with different addition amounts, b is the total heat release curve of the composite material with different addition amounts, c is the smoke release rate curve of the composite material with different addition amounts, and d is the total smoke release curve of the composite material with different addition amounts.

[0024] Figure 5 The figures show the smoke density and smoke toxicity curves of composite materials with different structures in the embodiments of the present invention. Among them, a is the smoke density curve of TPU and its composite materials, b is the highest smoke density of all materials, c is the CO2 production, and d is the CO production, which shows the excellent smoke and toxicity suppression effect of the smoke suppressant on the materials.

[0025] Figure 6 These are the thermogravimetric curves of composite materials with different structures in the embodiments of the present invention. a is the thermogravimetric curve of the sample under nitrogen gas, and b is the derivative thermogravimetric curve of the sample under nitrogen gas.

[0026] Figure 7 The figures show the steady-state tubular furnace combustion test curves of composite materials with different structures in the embodiments of the present invention. a is the light transmittance of the composite material, b is the total shading rate of the composite material, c is the CO2 concentration of the composite material, d is the total CO2 yield of the composite material, e is the CO concentration of the composite material, and e is the total CO yield of the composite material. Detailed Implementation

[0027] To further illustrate the technical solution of the present invention, preferred embodiments are described below in conjunction with examples. However, it should be understood that these descriptions are merely for further illustrating the features and advantages of the present invention, and not for limiting the scope of the claims. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0028] Example 1: Preparation of alumina nanoparticles

[0029] (1) Dissolve aluminum nitrate in deionized water and stir for 1 hour to form a homogeneous solution. Under continuous stirring, slowly add ammonia water to allow it to precipitate fully. The pH value of the suspension obtained after full precipitation is about 9.

[0030] (2) The above suspension was filtered to obtain a white precipitate, which was washed three times with deionized water. The precipitate was collected and dried in a forced-air oven for 12 hours at a temperature of 100°C.

[0031] (3) The dried sample was calcined in a muffle furnace for 4 hours at a temperature of 600°C to obtain white alumina nanoparticles.

[0032] Example 2: Preparation of alumina nanosheets

[0033] (1) Add aluminum isopropoxide to a mixture of anhydrous ethanol and deionized water, stir at 80°C for 1 h, and then transfer the mixture to a stainless steel autoclave with a Teflon liner and hydrothermally treat at 200°C for 24 h.

[0034] (2) The product obtained by hydrothermal treatment was filtered, and the precipitate obtained by filtration was washed three times with deionized water and ethanol respectively. The precipitate was collected and placed in a forced-air drying oven to dry for 12 hours at a temperature of 100°C.

[0035] (3) The dried sample was calcined in a muffle furnace for 4 hours at a temperature of 600°C to obtain white alumina nanosheets.

[0036] Example 3: Preparation of alumina nanospheres

[0037] (1) Dissolve aluminum nitrate in isopropanol and stir for 1 hour to form a homogeneous solution. Add glycerol slowly while stirring continuously to mix it thoroughly. Transfer the mixed solution to a stainless steel autoclave with a Teflon liner and hydrothermally treat it at 180°C for 16 hours.

[0038] (2) The above suspension was filtered to obtain a white precipitate, which was washed three times with ethanol. The precipitate was collected and dried in a forced-air oven at 60°C for 12 hours.

[0039] (3) Disperse the dried sample in a 1:1 mixture of water and ethanol and stir gently. Stir for 16 hours at a stirring rate of 300 rpm.

[0040] (4) Centrifuge the above mixed solution, wash it three times with ethanol, collect the precipitate, and dry it in a forced-air oven for 12 hours at a temperature of 60°C.

[0041] (5) The dried sample was calcined in a muffle furnace for 4 hours at a temperature of 500°C to obtain white alumina nanospheres.

[0042] Example 4: Preparation of a Highly Effective Smoke Suppressant and Toxicity Reducer

[0043] (1) The different Al2O3 supports prepared were uniformly dispersed in n-hexane, the gas in the pores of the supports was removed, the stirring time was 1 h, and the stirring rate was 300 rpm.

[0044] (2) Slowly add the nickel nitrate aqueous solution to the above mixed suspension. After the addition is complete, the surface loading of the active component is completed.

[0045] (3) Stir the above mixture for 60 minutes until it is evenly mixed, and then dry it in a forced-air oven for 12 hours at a temperature of 100℃.

[0046] (4) The dried sample was calcined in a muffle furnace for 8 hours at a temperature of 700°C to obtain a high-efficiency smoke-suppressing and toxicity-reducing hybrid material.

[0047] Example 5: Preparation of flame-retardant TPU composite materials with different smoke suppressant dosages

[0048] (1) Dry the TPU masterbatch in an oven for 6 hours to remove moisture and set aside for use;

[0049] (2) Dissolve the dried TPU masterbatch in N,N-dimethylformamide (DMF), add the smoke suppressant to the mixed solution under stirring, stir to mix evenly, then pour the mixed solution into water to wash away the excess DMF solution, and place the precipitate in an 80°C blower box to dry for a certain period of time to obtain the TPU composite material.

[0050] (4) Based on different amounts of smoke suppressant (0, 1, 2, 3 wt%), the prepared composite materials are named TPU, 1 wt% NiO / Al2O3-P / TPU, 2 wt% NiO / Al2O3-P / TPU and 3 wt% NiO / Al2O3-P / TPU.

[0051] Figure 4 The combustion performance of flame-retardant TPU composites with different amounts of smoke suppressant was investigated. Due to the high flammability of TPU, the samples burned violently after ignition, releasing a large amount of smoke. The figure shows that the addition of smoke suppressant had a relatively small impact on heat release, but significantly reduced the total amount of smoke from the composite material. The higher the amount added, the better the smoke suppression effect. Therefore, a 3wt% NiO / Al2O3-P / TPU material was selected for further investigation and analysis.

[0052] Example 6: Preparation of flame-retardant TPU composite materials with smoke suppressants of different structures

[0053] (1) Dry the TPU masterbatch in an oven for 6 hours to remove moisture and set aside for use;

[0054] (2) Dissolve the dried TPU masterbatch in N,N-dimethylformamide (DMF), add the smoke suppressant to the mixed solution under stirring, stir to mix evenly, then pour the mixed solution into water to wash away the excess DMF solution, and place the precipitate in an 80°C blower box to dry for a certain period of time to obtain the TPU composite material.

[0055] (4) Based on the smoke suppressant with different structures (NiO, Al2O3, NiO / Al2O3-P, NiO / Al2O3-S, NiO / Al2O3-M), the amount of addition is 3wt%, and the resulting composite material is named NiO / TPU, Al2O3 / TPU, NiO / Al2O3-P / TPU, NiO / Al2O3-S / TPU and NiO / Al2O3-M / TPU.

[0056] Figure 5 The smoke density and smoke toxicity curves of composite materials with different structures in the embodiments of the present invention demonstrate the excellent smoke and toxicity suppression effect of the smoke suppressant on the material. The sheet-shaped smoke suppressant has the best effect, reaching 48%, and its toxicity is also significantly reduced compared with pure TPU. Figure 6 The steady-state tubular furnace combustion process of the TPU sample and the composite material was demonstrated. Due to the high flammability of TPU, the sample burned violently after ignition, accompanied by the release of a large amount of smoke. In contrast, the addition of the highly efficient smoke suppressant of this invention reduced the total amount of smoke and the toxicity of the smoke from the composite material. Specifically, the total smoke volume of NiO / Al2O3-S / TPU was reduced by 28.5%, the amount of CO was reduced by 65.7%, and the toxicity was significantly reduced, demonstrating excellent smoke suppression and toxicity reduction performance.

[0057] Figure 2 The images show the XRD patterns of smoke suppressants with different structures in the embodiments of the present invention. The characteristic peak of Al2O3 appears in the components of all smoke suppressants, and the characteristic peak of AlNi alloy appears in some samples.

[0058] Figure 3 The images shown are SEM images of smoke suppressants with different structures in the embodiments of the present invention. The prepared smoke suppressants have different structures and sizes. The particulate smoke suppressant has a size in the range of 50-100 nm; the flake smoke suppressant has a size in the range of 5-30 μm; and the microsphere smoke suppressant has a size in the range of 200-500 nm.

[0059] Figure 4The combustion performance curves of flame-retardant TPU composite materials with different smoke suppressant addition amounts in the embodiments of the present invention show the influence of different smoke suppressant addition amounts on the combustion process of TPU materials. Among them, the addition amount of 3wt% has the best smoke suppressant effect, reaching 40% smoke suppressant effect.

[0060] Figure 5 The smoke density and smoke toxicity curves of composite materials with different structures in the embodiments of the present invention demonstrate the excellent smoke and toxicity suppression effect of the smoke suppressant on the material. The sheet-shaped smoke suppressant has the best effect, reaching 48%, and its toxicity is also significantly reduced compared with pure TPU.

[0061] Figure 6 The thermogravimetric curves of composite materials with different structures in the embodiments of the present invention are shown. The addition of smoke suppressant advances the decomposition of TPU and increases the residual carbon from 4.87 wt% to 9.41 wt%. Smoke suppressant can increase the carbon layer formed by combustion and inhibit heat and mass transfer processes.

[0062] Figure 7 The figures show the steady-state combustion test curves of composite materials in tubular furnaces with different structures in the embodiments of the present invention. The addition of smoke suppressant significantly reduces the total amount of flue gas and flue gas toxicity of composite materials, decreases CO yield, and increases CO2 production.

Claims

1. The application of a high-efficiency smoke-suppressing and toxicity-reducing hybrid material, characterized in that: The aforementioned high-efficiency smoke-suppressing and toxicity-reducing hybrid material is added to thermoplastic polyurethane as an additive to improve the flame retardant and smoke-suppressing properties of the composite material. The highly efficient smoke-suppressing and toxicity-reducing hybrid material is prepared by a method including the following steps: Step 1: First, synthesize alumina nanoparticles, alumina nanosheets, and alumina nanospheres as carriers for smoke-suppressing and toxicity-reducing hybrid materials; Step 2: Disperse the support obtained in Step 1 uniformly in n-hexane, and add completely dissolved nickel nitrate aqueous solution dropwise to the system under stirring. After the addition is complete, continue stirring and mixing for a certain period of time to complete the loading of the active component. Step 3: Next, place the mixed solution obtained in Step 2 into a forced-air drying oven for drying. After drying, calcine it at high temperature in a muffle furnace to obtain a high-efficiency smoke-suppressing and toxicity-reducing hybrid material.

2. The application according to claim 1, characterized in that: In step 1, the alumina nanoparticles are prepared by co-precipitation and have a size in the range of 50-100 nm; the alumina nanosheets are prepared by hydrothermal method and have a size in the range of 5-30 μm; and the alumina nanospheres are prepared by template method and have a size in the range of 200-500 nm.

3. The application according to claim 1, characterized in that: In the aforementioned high-efficiency smoke-suppressing and toxicity-reducing hybrid material, the active center, nickel oxide, accounts for 10 wt% of the total mass.

4. The application according to claim 1, characterized in that: In step 2, the concentration of the nickel nitrate aqueous solution is 0.1 mol / L, the mixing and stirring rate is 300 rpm, and the stirring time is 30-60 min.

5. The application according to claim 1, characterized in that: In step 3, the drying temperature is 80-120℃ and the drying time is 6-12 h.

6. The application according to claim 1, characterized in that: In step 3, the calcination temperature is 400-600℃ and the calcination time is 6-10 h.

7. The application according to claim 1, characterized in that: When the highly efficient smoke-suppressing and toxicity-reducing hybrid material is added as an additive to thermoplastic polyurethane, the composite material is constructed using a solvent method.

8. The application according to claim 1, characterized in that: The amount of the high-efficiency smoke-suppressing and toxicity-reducing hybrid material added is 1-3 wt% of the total mass of the composite material.

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