Aerogel modified gas-phase TPU (thermoplastic polyurethane) flame-retardant material and preparation method thereof
By preparing TPE materials using aerogel-modified flame retardants, the problem of dripping during combustion of TPE materials was solved, the flame retardant and heat insulation properties were improved, and the mechanical properties of the materials were maintained, making them suitable for industrial production.
Patent Information
- Application Number
- CN202511776494.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-29
- Publication Date
- 2026-01-16
AI Technical Summary
Existing TPE materials exhibit dripping during combustion, poor flame retardancy, insufficient thermal insulation, and compromised mechanical properties, making industrial production difficult.
Aerogel-modified flame retardant, including aminated silica aerogel powder, diethyl aluminum hypophosphite, high-phosphorus polymers, alumina, and titanium dioxide, is used to prepare gaseous TPE flame retardant materials through blending and extrusion granulation. This process forms a porous carbon layer and provides gaseous flame retardant effects, thereby improving flame retardant performance and thermal insulation.
The resulting TPE material exhibits no dripping, excellent flame retardancy, good thermal insulation, and mechanical properties, making it suitable for industrial production.
Smart Images
Figure CN121343355A_ABST
Abstract
Description
[0001] This application is a divisional application of application number 2024113727465, filed on September 29, 2024, entitled "An aerogel-modified vapor phase TPE flame retardant material and its preparation method". Technical Field
[0002] This solution relates to the field of polymer materials technology, specifically to an aerogel-modified gaseous TPU flame retardant material and its preparation method. Background Technology
[0003] TPE is a material that combines the high elasticity, high strength, high resilience, and injection molding properties of rubber. It mainly includes thermoplastic polyester elastomers, thermoplastic polyolefin elastomers, thermoplastic dynamic vulcanized rubber, polyether-based TPU, polyester-based TPU, and thermoplastic rubber. TPE is widely used in many industries such as automotive, electronics, medical devices, sporting goods, and household goods. However, because TPE is usually composed of multiple polymers and often contains a large number of flammable hydrocarbon chains, it poses a significant fire hazard under certain conditions. For example, in the electronics industry, if ordinary TPE materials are used for components such as wires and cables, appliance casings, and sockets, a circuit fault, overload, or short circuit with an open flame can cause the TPE to ignite rapidly, potentially leading to a serious fire and causing incalculable casualties and property damage. Therefore, flame-retardant modification of TPE is crucial.
[0004] Currently, commonly used flame retardants for TPE include halogenated, nitrogen-phosphorus-based, and inorganic types. Materials containing halogenated flame retardants produce large amounts of smoke and toxic, corrosive gases during combustion. Many countries, including the European Union, have enacted relevant laws and regulations to control the use of halogenated flame retardants. Inorganic flame retardants are added in larger quantities, typically around 50%. While they can achieve flame retardant effects, they severely affect the processing and mechanical properties of the material. Currently, phosphorus-nitrogen-based flame retardants in TPE materials (especially TPEE and TPU), even when added in large quantities, still exhibit dripping and can ignite flammable materials such as cotton, severely impacting the flame retardant rating and causing chain reactions during combustion (such as igniting other flammable materials after falling). Therefore, developing a non-dripping, highly efficient flame-retardant, heat-insulating, and mechanically sound TPE flame-retardant material that can be industrially produced is a pressing issue that the market needs to address. Summary of the Invention
[0005] The present invention aims to provide an aerogel-modified gaseous TPE flame retardant material and its preparation method, so as to obtain a TPE flame retardant material with excellent flame retardant performance, significant heat insulation effect and excellent mechanical properties. At the same time, the material does not exhibit dripping during use and can be industrialized.
[0006] To achieve the above objectives, the present invention adopts the following technical solution: an aerogel-modified gaseous TPE flame retardant material, comprising the following components in parts by weight: 70-90 parts TPE, 10-30 parts flame retardant, and 0.1-0.5 parts antioxidant; The flame retardant comprises the following components in parts by weight: 30-60 parts of aerogel-modified aluminum diethyl phosphite, 20-50 parts of high-phosphorus polymer, 5-20 parts of synergist, 0.5-2 parts of surface modifier, and 0.5-5 parts of petroleum-based rubber processing oil.
[0007] Preferably, the TPE is any one of thermoplastic polyurethane elastomer, thermoplastic polyester elastomer, thermoplastic polyolefin elastomer, thermoplastic dynamic vulcanized rubber, and thermoplastic rubber.
[0008] Preferably, the high-phosphorus polymer is either piperazine polyphosphate or ammonium polyphosphate.
[0009] Preferably, the aerogel-modified diethyl aluminum hypophosphite comprises the following components in parts by weight: 2-10 parts of aminated silica aerogel powder and 80-100 parts of diethyl aluminum hypophosphite.
[0010] Preferably, the synergist comprises the following components in parts by weight: 4-15 parts titanium dioxide and 3-10 parts aluminum oxide.
[0011] Preferably, the method for preparing the flame retardant includes the following steps: S1: Weigh out a certain amount of aminated silica aerogel powder and diethyl aluminum hypophosphite and place them in a high-speed mixer. The mixer speed is 500-1500 r / min. Stir at high speed for 10-30 min at 80-130℃. S2: Add high-phosphorus polymer, alumina and titanium dioxide to the high-speed mixer in S1 in sequence, and then spray the surface modifier during the mixing process. S3, after the surface modifier is sprayed, add petroleum-based rubber processing oil and continue stirring for 12-20 minutes to obtain the flame retardant.
[0012] Preferably, in S1, the mass ratio of aminated silica aerogel powder to diethyl aluminum hypophosphite is 1:(20-30).
[0013] Preferably, in S2, the mass ratio of ammonium polyphosphate, titanium dioxide and alumina is (30-40):(12-6):(8-4).
[0014] This invention also provides another technical solution: a method for preparing aerogel-modified fumed TPE flame-retardant material. The method involves uniformly mixing TPE, flame retardant, and antioxidant, adding the mixture to a twin-screw extruder, controlling the main extruder speed at 350-550 r / min, the processing temperature in the first zone at 140-180℃, the processing temperature in other zones at 150-200℃, and the die head temperature at 170-200℃, followed by melt blending, extrusion granulation, and finally obtaining the aerogel-modified fumed TPE flame-retardant material.
[0015] Preferably, the length-to-diameter ratio of the extrusion screw is (20-30):1.
[0016] Mechanism of action: This technical solution incorporates aminated silica aerogel powder. Aminated silica aerogel is a porous network structure material with high porosity and small pore size. After other components produce non-combustible gases during combustion, these gases can rapidly reach the combustion site through the high-porosity nanopores, hindering the combustion process and reducing the flame propagation speed. Furthermore, the extremely low thermal conductivity of aminated silica aerogel allows its infinitely extended heat conduction path to absorb the heat generated by combustion, lowering the flame temperature and making it difficult to maintain the thermal decomposition temperature, thus providing thermal insulation and promoting the gas phase.
[0017] This technical solution, due to the addition of alumina and titanium dioxide, allows titanium dioxide and alumina particles to cover the material surface, forming a protective layer. Especially after the intervention of aerogel silica molecules, the synergistic effect significantly improves the stability of the carbon layer. Simultaneously, they undergo a crystal transformation during heating, a process that is endothermic, which rapidly cools the already formed carbon layer, further solidifying it. Therefore, for TPE materials prone to dripping, alumina and titanium dioxide are effective in fixing the carbon layer.
[0018] Due to the addition of ammonium polyphosphate (APP), the flame-retardant mechanism of this technical solution mainly includes the following aspects: Expansion and carbonization: When heated, ammonium polyphosphate expands and forms a carbonized layer. This carbonized layer can isolate oxygen and heat, thereby preventing the spread of fire. Air isolation: The polyphosphoric acid and non-combustible gases produced by the decomposition of ammonium polyphosphate cover the material surface, forming an isolation layer that prevents oxygen from entering the material. Heat insulation: The non-combustible gases and carbonized layer produced by the decomposition of ammonium polyphosphate can reduce the temperature of the material and reduce heat transfer. Release of non-combustible gases: When ammonium polyphosphate decomposes upon heating, it releases non-combustible gases such as nitrogen and ammonia. These gases can dilute the oxygen in the air, thereby blocking the oxygen supply.
[0019] The carbon layer formation process in this technical solution is as follows: Ammonium polyphosphate acts as an acid source, decomposing and releasing inorganic acids at a relatively low temperature. At a temperature slightly higher than the acid source release temperature, the released inorganic acids undergo esterification with alcohols. The flame-retardant material gradually melts and softens before and during esterification. The water vapor generated during the reaction and the non-flammable gases released by the gas source cause the entire molten system to foam and expand. Simultaneously, the ester dehydrates and carbonizes, forming inorganic matter and carbon residue. Subsequently, the system gels and solidifies, forming a porous foamed carbon layer, and the reaction ends. These steps occur almost simultaneously but must be carried out in a strict order. If any reaction is not carried out in a timely manner, the expansion and flame-retardant effect cannot be achieved. The formed carbon layer itself is non-flammable and has heat insulation and oxygen barrier functions, which can weaken the heat conduction between the polymer matrix and the external heat source and prevent the combustible gases generated by degradation from entering the combustion zone as fuel to support combustion. At the same time, the carbon layer can also prevent the diffusion and transfer of oxygen into the polymer interior. When combustion does not receive enough oxygen and heat energy, the combustion process is stopped.
[0020] This technical solution utilizes the addition of piperazine polyphosphate. During the initial, lower-temperature combustion phase, piperazine decomposes to produce phosphoric acid and polyphosphoric acid, catalyzing the degradation of the matrix material to form a char layer. Furthermore, the piperazine structure on the polyphosphate exhibits excellent char-forming properties, and the resulting char layer after combustion can block heat, flammable volatiles, and oxygen, further protecting the matrix material. Moreover, its decomposition products, phosphorooxygenates and phosphorus free radicals, interrupt the exothermic process and inhibit combustion through gas-phase channels (including the high porosity present in silica aerogels) via a free radical mechanism. Additionally, the focused piperazine phosphate produces non-flammable gases such as N2 and NH3 during combustion, diluting flammable gases and inhibiting combustion. Finally, the piperazine ring structure, similar to a benzene ring, exhibits outstanding thermal stability, and the piperazine segments improve the interaction between the titanium dioxide, alumina, and the elastomer matrix in the components.
[0021] This technical solution leverages the synergistic effects of silica aerogel, high-phosphorus polymers, and synergists to enhance the overall performance of the flame-retardant system by improving char layer formation efficiency, stability, structure, and gas-phase inhibition. Silica aerogel, in particular, acts as a bridge connecting the various components through its nanopores.
[0022] Compared with existing technologies, the beneficial effects of this solution are as follows: (1) The aerogel-modified gas phase TPE flame retardant material provided and prepared by this technical solution has a high pore density due to the high pore density of the aerogel-modified diethyl aluminum hypophosphite. By increasing the nanopores, the gas phase effect is promoted, resulting in a strong gas phase flame retardant effect produced by the gas phase flame retardant, and it does not destroy the fixed carbon layer generated during the original combustion. It has both gas phase and char formation flame retardant effects.
[0023] (2) The aerogel-modified gaseous TPE flame retardant material provided and prepared by this technical solution has the advantages of low flame retardant addition, no dripping phenomenon during combustion, and high bonding strength between the combustion layer and the secondary combustion layer.
[0024] (3) The aerogel-modified gaseous TPE flame retardant material provided and prepared by this technical solution can reduce the thermal conductivity of the material, thereby giving the material the advantage of good thermal insulation.
[0025] (4) The aerogel-modified gaseous TPE flame retardant material provided and prepared by this technical solution greatly improves the flame retardant effect through the dual synergistic effect of inorganic and organic materials, while having a low impact on mechanical properties.
[0026] (5) Compared with traditional surface modifiers, the surface modifier selected in this technical solution can improve the compatibility between TPE and flame retardant, and at the same time, can further improve the mechanical properties of the material, while ensuring that the material is fed evenly during processing.
[0027] (6) The aerogel-modified gaseous TPE flame retardant material provided and prepared by this technical solution can reduce the dust of flame retardant due to the addition of petroleum-based rubber processing oil, and at the same time, improve lubricity.
[0028] (7) The preparation method of aerogel modified gas phase TPE flame retardant material provided in this technical solution sets the processing temperature of the first zone to 140-180℃, the processing temperature of other zones to 150-200℃, and the die head temperature to 170-200℃ during the material preparation process. This can prevent the TPE flame retardant material from being degraded due to excessively high temperature, which would affect the performance of the material. At the same time, it can also prevent the TPE flame retardant material from being plasticized poorly with the flame retardant powder due to excessively low temperature, which would affect the performance of the material.
[0029] (8) The preparation method of the aerogel-modified gaseous TPE flame retardant material provided by this technical solution can realize industrial production and the preparation process is simple. Attached Figure Description
[0030] Figure 1 This is a thermogravimetric (TG) diagram of the flame retardant prepared in Example 1 of the present invention. Detailed Implementation
[0031] The following detailed description illustrates the specific implementation method: Example 1 An aerogel-modified vapor-phase TPE flame-retardant material comprises the following components in parts by weight: 70-90 parts TPE, 10-30 parts flame retardant, and 0.1-0.5 parts antioxidant; in this embodiment, the amount of TPE is 2700g, the amount of flame retardant is 309g, and the amount of antioxidant is 0.9g. The flame retardant comprises the following components in parts by weight: 30-60 parts of aerogel-modified aluminum diethyl phosphite, 20-50 parts of high-phosphorus polymer, 5-20 parts of synergist, 0.5-2 parts of surface modifier, and 0.5-5 parts of petroleum-based rubber processing oil. The petroleum-based rubber processing oil is any one of aromatic oil, naphthenic oil, or paraffin oil. In this embodiment, the amount of aerogel-modified aluminum diethyl phosphite is 150g, the amount of high-phosphorus polymer is 120g, the amount of synergist is 30g, the amount of surface modifier is 3g, and the petroleum-based rubber processing oil is paraffin oil, with an amount of 6g. The paraffin oil is manufactured by Formosa Petrochemical Corporation. The aerogel-modified diethyl aluminum hypophosphite comprises the following components in parts by weight: 2-10 parts of aminated silica aerogel powder and 80-100 parts of diethyl aluminum hypophosphite. In this embodiment, the amount of aminated silica aerogel powder is 6g and the amount of diethyl aluminum hypophosphite is 144g. The manufacturer of the aminated silica aerogel powder is China Chemical Hualu New Materials Co., Ltd., and the manufacturer of diethyl aluminum hypophosphite is Chongqing Kejufu New Materials Co., Ltd. The TPE is any one of thermoplastic polyurethane elastomer (TPU), thermoplastic polyester elastomer (TPEE), thermoplastic polyolefin elastomer (TPO), thermoplastic dynamic vulcanizate (TPV), and thermoplastic rubber (TPR); the thermoplastic polyurethane elastomer (TPU) is any one of polyester-type TPU and polyether-type TPU. In this embodiment, polyether-type TPU is selected as the TPE, and the manufacturer of polyether-type TPU is Lubrizol Corporation of the United States. The high-phosphorus polymer is either piperazine polyphosphate or ammonium polyphosphate. In this embodiment, the high-phosphorus polymer is ammonium polyphosphate. Both piperazine polyphosphate and ammonium polyphosphate are manufactured by Shifang Changfeng Chemical Co., Ltd. The synergist comprises the following components in parts by weight: 4-15 parts titanium dioxide and 3-10 parts aluminum oxide. In this embodiment, the amount of titanium dioxide is 18g and the amount of aluminum oxide is 12g. Both titanium dioxide and aluminum oxide are commercially available products. The antioxidant is any one or a combination of antioxidant 1010 and antioxidant 168. In this embodiment, antioxidant 1010 is selected and manufactured by BASF AG, Germany. The surface modifier is any one or a combination of two of amino polymers, vinyl oligomers, alkylamino copolymers, and titanium chelates. The addition of the surface modifier primarily improves the compatibility between the flame retardant and TPE, while also enhancing the water and oil resistance of the flame retardant. In this embodiment, N-phenyl-3-aminopropyltrimethoxysilane is selected as the surface modifier, and it is commercially available.
[0032] The preparation method of flame retardant includes the following steps: S1: Weigh out a certain amount of aminated silica aerogel powder and aluminum diethylphosphite and place them in a high-speed mixer. The mixer speed is 500-1500 r / min. Stir at high speed for 10-30 min at 80-130℃. The mass ratio of aminated silica aerogel powder to aluminum diethylphosphite is 1:(20-30). In this example, the mass ratio of aminated silica aerogel powder to aluminum diethylphosphite is 1:24. Stir at high speed for 15 min at 100℃. The mixer speed is 800 r / min. S2: Add ammonium polyphosphate, alumina and titanium dioxide to the high-speed mixer in S1 in sequence. Then, spray a surface modifier during the mixing process. The mass ratio of ammonium polyphosphate, titanium dioxide and alumina is (30-40):(12-6):(8-4). In this embodiment, the mass ratio of ammonium polyphosphate, titanium dioxide and alumina is 20:3:2. The amount of surface modifier is 3g. S3. After the surface modifier is sprayed, paraffin oil is added and stirring is continued for 12-20 minutes to obtain the flame retardant. In this embodiment, stirring is carried out for 15 minutes.
[0033] A method for preparing an aerogel-modified fumed TPE flame-retardant material is as follows: 2700g of polyether-type TPU, 309g of flame retardant, and 0.9g of antioxidant are mixed evenly and added to a twin-screw extruder. The main extruder speed is controlled at 350-550 r / min, the processing temperature in the first zone is 140-180℃, the processing temperature in other zones is 150-200℃, the die head temperature is 170-200℃, the main extruder current is less than the rated current, and the length-to-diameter ratio of the extrusion screw is (20-30):1. The mixture is then melt-blended, extruded, and granulated to obtain the aerogel-modified fumed TPE flame-retardant material. In this embodiment, the main extruder speed is 400 r / min, the processing temperature in the first zone is 150℃, the processing temperature in other zones is 160℃, the die head temperature is 180℃, and the length-to-diameter ratio of the extrusion screw is 20:1. Examples 1-6 prepared various aerogel-modified gaseous TPE flame retardant materials according to the raw materials and dosages shown in Table 1, and also according to the preparation method of Example 1.
[0034] The raw materials and their amounts used in the preparation of the aerogel-modified gaseous TPE flame-retardant materials in Examples 1-6 are shown in Table 1.
[0035] Table 1
[0036] In Examples 3-4, the thermoplastic polyester elastomer used was manufactured by LG Chem of South Korea; in Examples 5-6, the thermoplastic polyolefin elastomer used was manufactured by Wanhua Chemical Group Co., Ltd.
[0037] Comparative Example 1 Unlike Example 1, 2700g of commercially available polyether-type TPU was taken and its performance was tested. The results are shown in Table 2.
[0038] Comparative Example 2 Unlike Example 1, in this aerogel-modified gaseous TPE flame retardant material, silica aerogel powder is used instead of aminated silica aerogel powder in the flame retardant, and the amount of silica aerogel powder used is 6g.
[0039] In the preparation method of the flame retardant, in S1, 6g of silica aerogel powder is used to replace 6g of aminated silica aerogel powder.
[0040] Comparative Example 3 Unlike Example 1, this is an aerogel-modified gaseous TPE flame retardant material, in which the flame retardant does not contain aminated silica aerogel powder, and the amount of aminated silica aerogel powder added is 0g.
[0041] The method for preparing the flame retardant, in step S1, does not include aminated silica aerogel powder.
[0042] Comparative Example 4 Unlike Example 1, in this aerogel-modified gaseous TPE flame retardant material, the mass ratio of aminated silica aerogel powder to aluminum diethylphosphite is 1:14, that is, the amount of aminated silica aerogel powder is 10g and the amount of aluminum diethylphosphite is 140g.
[0043] In the preparation method of the flame retardant, in S1, the amount of aminated silica aerogel powder is 6g and the amount of diethyl aluminum hypophosphite is 120g.
[0044] Comparative Example 5 Unlike Example 1, in this aerogel-modified gaseous TPE flame retardant material, the mass ratio of aminated silica aerogel powder to aluminum diethylphosphite is 1:49, that is, the amount of aminated silica aerogel powder is 3g and the amount of aluminum diethylphosphite is 147g.
[0045] In the preparation method of the flame retardant, in S1, the amount of aminated silica aerogel powder is 3g and the amount of diethylaluminum hypophosphite is 147g.
[0046] Comparative Example 6 Unlike Example 1, in an aerogel-modified gaseous TPE flame retardant material, the synergist in the flame retardant only includes titanium dioxide and does not contain aluminum oxide, and the amount of titanium dioxide used is 30g.
[0047] The method for preparing the flame retardant, in S2, the amount of alumina added is 0g, and the amount of titanium dioxide is 30g.
[0048] Comparative Example 7 Unlike Example 1, in an aerogel-modified gaseous TPE flame retardant material, the synergist in the flame retardant only includes alumina and does not include titanium dioxide, and the amount of alumina used is 30g.
[0049] The method for preparing the flame retardant, in S2, the amount of alumina added is 30g, and the amount of titanium dioxide is 0g.
[0050] The detection results of Examples 1-6 and Comparative Examples 1-11 are shown in Table 2.
[0051] Table 2
[0052] like Figure 1 It is known that the flame retardant prepared in Example 1 has a thermal decomposition temperature of over 300°C, while the general processing temperature of TPE elastomer materials is around 200°C. Therefore, the flame retardant in this patent will not cause a decline in the material's thermal and mechanical properties during material processing due to the thermal decomposition of the flame retardant.
[0053] As shown in Table 2, the aerogel-modified gaseous TPE flame retardant materials provided and prepared in Examples 1-6 have the advantages of excellent flame retardant performance and mechanical properties, and the material does not exhibit dripping during use.
[0054] As shown in Table 2, compared with Comparative Example 1, the pure polyether-type TPU material has better mechanical properties, but its flame retardant properties are poor and it is accompanied by dripping phenomenon.
[0055] As shown in Table 2, compared with Comparative Example 2, although the flame retardant properties of the material after replacing the aminated silica aerogel powder with silica aerogel powder are comparable to those of Example 1, the mechanical properties of Comparative Example 2 are relatively poor.
[0056] As shown in Table 2, compared with Comparative Example 3, if aminated silica aerogel powder is not added to the flame retardant, the mechanical properties and flame retardant properties of the material are relatively poor, and dripping phenomenon is also present.
[0057] As shown in Table 2, compared with Comparative Examples 4-5, the amount of aminated silica aerogel powder used in Example 1 was too much or too little. Although its mechanical properties were better than those in Example 1, its flame retardant properties were significantly lower than those in Example 1, and it was accompanied by dripping phenomenon.
[0058] As shown in Table 2, compared with Comparative Example 6, although the mechanical properties of the flame retardant without the addition of alumina are better than those of Example 1, its flame retardant properties are significantly lower than those of Example 1, and it is accompanied by dripping phenomenon.
[0059] As shown in Table 2, compared with Comparative Example 7, although the mechanical properties of the flame retardant without the addition of titanium dioxide are better than those of Example 1, its flame retardant properties are significantly lower than those of Example 1, and it is accompanied by dripping phenomenon.
[0060] The above descriptions are merely embodiments of the present invention, and common knowledge such as specific technical solutions and / or characteristics are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the technical solutions of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.
Claims
1. An aerogel modified aerogel flame retardant material, characterized in that: The flame retardant material comprises the following components in parts by weight: TPU 70-90 parts, flame retardant 10-30 parts, and antioxidant 0.1-0.5 parts. The flame retardant comprises the following components in parts by weight: aerogel modified diethyl aluminum hypophosphite 30-60 parts, high-phosphorus polymer 20-50 parts, synergist 5-20 parts, surface modifier 0.5-2 parts, and petroleum rubber processing oil 0.5-5 parts.
2. The aerogel modified gas phase TPU flame retardant material according to claim 1, characterized by: The high-phosphorus polymer is any one of polyphosphazene and ammonium polyphosphate.
3. The aerogel modified flame retardant gas phase TPU material and the preparation method thereof according to claim 1 or 2, characterized in that: The aerogel modified diethyl aluminum hypophosphite comprises the following components in parts by weight: amino-silica aerogel powder 2-10 parts and diethyl aluminum hypophosphite 80-100 parts.
4. The aerogel modified gas phase TPU flame retardant material according to claim 3, characterized by: The synergist comprises the following components in parts by weight: titanium dioxide 4-15 parts and aluminum oxide 3-10 parts.
5. The aerogel modified gas phase TPU flame retardant material according to claim 4, characterized by: The preparation method of the flame retardant comprises the following steps: S1: a certain amount of amino-silica aerogel powder and diethyl aluminum hypophosphite are respectively weighed and placed in a high-speed mixer, the rotating speed of the mixer is 500-1500 r / min, and the high-speed stirring is performed at 80-130℃ for 10-30 min; S2: the high-speed mixer in S1 is further added with high-phosphorus polymer, aluminum oxide and titanium dioxide in sequence, and then the surface modifier is sprayed in the stirring process; S3: after the spraying of the surface modifier is completed, the petroleum rubber processing oil is further added, and the stirring is continuously performed for 12-20 min to obtain the flame retardant.
6. The aerogel modified gas phase TPU flame retardant material according to claim 5, characterized by: In S1, the mass ratio of the amino-silica aerogel powder to the diethyl aluminum hypophosphite is 1:(20-30).
7. The aerogel modified gas phase TPU flame retardant material according to claim 6, characterized by: In S2, the mass ratio of the ammonium polyphosphate, titanium dioxide and aluminum oxide is (30-40):(12-6):(8-4) in sequence.
8. The aerogel modified gas phase TPU flame retardant material according to claim 7, characterized by: The TPU, the flame retardant and the antioxidant are uniformly mixed, and then added into a double-screw extruder, the rotating speed of the main machine is controlled at 350-550 r / min, the processing temperature of the first area is controlled at 140-180℃, the processing temperature of other areas is controlled at 150-200℃, and the die temperature is controlled at 170-200℃, so that the melt blending, extrusion and granulation are performed to obtain the aerogel modified gas-phase TPU flame retardant material.
9. The aerogel modified gas phase TPU flame retardant material according to claim 8, characterized by: The length-diameter ratio of the extrusion screw is (20-30):1.