TPU-based composite material and preparation method and application thereof

Abstract

The application belongs to the technical field of composite materials, and particularly relates to a TPU-based composite material and a preparation method and application thereof. The application discloses a preparation method of a TPU-based composite material, which comprises the following steps: mixing a dispersion liquid containing a nano-conductive material with a TPU part, and sequentially performing temperature dyeing treatment, acid bath treatment and surface hydrophobicity treatment to obtain the TPU-based composite material. The prepared TPU-based composite material has better conductivity than the TPU composite material prepared by the prior art, and has mechanical properties, sensing properties and hydrophobicity, and thus is excellent in the field of wearable electronic devices.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of composite materials, and particularly relates to a TPU-based composite material and a preparation method and application thereof. BACKGROUND

[0002] Thermoplastic polyurethane elastomer, also known as thermoplastic polyurethane rubber (TPU), has high elasticity of rubber and rigidity of plastic, can be melt-processed, and is suitable for high-precision and high-resolution printing. 3D printed TPU parts have good wear resistance, weather resistance, tensile strength, and hardness range, and are widely used in design fields, shoe material fields, clothing fields, biological and medical fields, and automobile fields.

[0003] Nano materials are concerned in the technical field of composite materials due to their special properties in optical properties, chemical reactivity, magnetism, superconductivity, and plastic deformation. In recent years, a kind of nano material, MXene, has attracted much attention. MXene material refers to a two-dimensional layered material derived from transition metal carbon / nitrogen / carbon nitride (such as Ti3C2). MXene, as a nano conductive material (nCMs) together with carbon nanotubes (CNTs) and graphene (Gr), can be combined with other materials to obtain composite materials with significantly improved conductivity, thermal conductivity, and electromagnetic shielding performance. The surface of the above-mentioned composite materials is widely used in the field of wearable devices after being hydrophobized.

[0004] Currently, there are two methods for the compounding of nCMs and TPU. Method one is to mix nCMs and TPU base material in a certain proportion, add necessary additives, and prepare a composite material by melt blending. Method two is to coat nCMs on the surface of 3D printed TPU parts by spraying, dipping or electrochemical deposition, and further dry to obtain a finished product. The two methods have different interactions. In the former method, nCMs are prone to agglomeration, and it is difficult for nCMs to be uniformly dispersed in the melt blending process, which not only leads to inconsistent conductivity of the finished product, but also affects the interlayer adhesion of the 3D printed part. In the latter method, for the formed TPU parts, it is easier to realize the conductive compounding of complex shape and structure, and the post-processing of the compounded nCMs is relatively simple, which can be completed by steps such as cleaning and curing. However, the bonding strength of nCMs on the surface of the TPU part is low, which affects the comprehensive performance of the composite material and cannot meet the actual needs.

[0005] CN107523040A discloses a low hardness, high resilience, conductive TPU material, and a preparation method thereof, which comprises the following steps: (1) mixing polymeric polyol, polyisocyanate, chain extender / crosslinking agent, antistatic agent and catalyst at 100-120 DEG C, and curing at 150-160 DEG C after reaction for 1-2 hours to obtain material A; (2) taking polyester type polyurethane material B, and extruding material A, material B and conductive material, and softening the materials at 150-180 DEG C to obtain a low hardness, high resilience, conductive TPU material. The multifunctional TPU material has low hardness and high resilience, but the nCMs cannot be uniformly dispersed, the internal adhesion of the TPU part is not enough, and the conductive performance and mechanical performance are affected, so it cannot be applied to wearable electronic devices, health monitoring devices and sports monitoring devices. The TPU material has strong internal adhesion but poor conductive performance and sensing performance without adding any nCMs, which limits its application in wearable fields; therefore, how to develop a TPU-based composite material, uniformly disperse nCMs in TPU and firmly combine nCMs with TPU, so as to have good conductive performance and consider mechanical performance, sensing performance and hydrophobic performance at the same time, and apply it to the field of wearable electronic devices has become a problem to be solved. SUMMARY

[0006] In order to overcome the shortcomings of the prior art, the purpose of the present application is to develop a TPU-based composite material and a preparation method thereof, to realize uniform dispersion of nCMs in TPU and firm combination of nCMs with TPU, so that the TPU-based composite material has good conductive performance and considers mechanical performance, sensing performance and hydrophobic performance at the same time, and is applied to the field of wearable electronic devices.

[0007] In one aspect, the present application provides a preparation method of a TPU-based composite material. The preparation method comprises: mixing a dispersion liquid containing a nano-conductive material with a TPU part, and performing temperature dyeing treatment, acid bath treatment and surface hydrophobicity treatment to obtain the TPU-based composite material.

[0008] The temperature dyeing treatment is from room temperature to 80 DEG C-95 DEG C, the temperature rising rate is 1.5-2 DEG C / min, and the holding time is 40-60 min.

[0009] Further, in the preparation method of the TPU-based composite material, the nano-conductive material is a mixture of one or more of carbon nanotubes, graphene and Mxene.

[0010] Further, the TPU part is prepared by using a fused deposition modeling 3D printing technology with TPU as a raw material.

[0011] Further, the amount of the nano-conductive material added is 2-10% of the mass of the TPU product.

[0012] Further, the dispersibility of the dispersion liquid is optimized by ultrasonic and mechanical stirring, the ultrasonic dispersion power is 300-500W, and the time is 30-60min; the mechanical stirring speed is 100-500rpm / min, and the time is 10-30min.

[0013] Further, C6H8O7, Zr(SO4)2, Al2(SO4)3, FeCl3, Ce2(SO4)3, LaCl3, deionized water and other raw materials are added to prepare an acid bath with different pH values, and transition metal ions Zr 4+ , Al 3+ , Fe 3+ or rare earth metal ions Ce 3+ , La 3+ are introduced to coordinate and "bridge" nCMs and TPU products, further strengthening the conductivity and improving the bonding strength of nCMs and TPU products.

[0014] Further, in order to improve the hydrophobicity of the TPU composite material, polydimethylsiloxane modified polyurethane or a mixture of hydroxyl-terminated polydimethylsiloxane modified polyurethane or polydimethylsiloxane modified polyurethane and hydroxyl-terminated polydimethylsiloxane modified polyurethane is used to treat the surface of the TPU composite material.

[0015] Further, the concentration of the hydrophobic treatment material is 2-5% by mass percentage.

[0016] On the other hand, the TPU-based composite material prepared by the above method has good conductivity while taking into account the mechanical properties and hydrophobicity, and is used to prepare wearable electronic devices.

[0017] Compared with the prior art, the technical scheme provided by the present application at least has the following beneficial effects or advantages:

[0018] The present application overcomes the defects of the prior art, and the nCMs and TPU are combined by using temperature dyeing treatment, so that the nCMs are uniformly distributed in the TPU and firmly combined with it, further transition metal ions are introduced to improve the conductivity of the TPU-based composite material, and then the surface of the above composite material is treated with hydrophobicity, forming a uniform hydrophobic film on the surface, and a TPU-based composite material is prepared, which has better conductivity and takes into account the mechanical properties, sensing properties and hydrophobicity, so that it can be applied to wearable electronic devices. BRIEF DESCRIPTION OF DRAWINGS

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 These are strain tensile images and resistivity images of the intermediate product CNTs-COOH / TPU from Example 1.

[0021] Figure 2 These are strain tensile images and resistivity images of the intermediate product CNTs-COOH / TPU from Example 2.

[0022] Figure 3 These are strain tensile images and resistivity images of the intermediate product CNTs-COOH / TPU from Example 3.

[0023] Figure 4 This is a super depth-of-field microscope image of the intermediate product CNTs-COOH / TPU from Example 6.

[0024] Figure 5 These are scanning electron microscope images of 3D-printed TPU parts at different magnifications.

[0025] Figure 6 These are scanning electron microscope images of Zr / CNTs-COOH / TPU from Example 6 at different magnifications.

[0026] Figure 7 These are strain tensile images and resistivity images of Zr / CNTs-COOH / TPU from Example 5.

[0027] Figure 8 These are sensor images of the intermediate products CNTs-COOH / TPU and Zr / CNTs-COOH / TPU from Example 6.

[0028] Figure 9 The image shown is a test image of the water contact angle of the TPU-based composite material prepared in Example 6. Detailed Implementation

[0029] The technical solution of the present invention will now be described with reference to embodiments. However, the present invention is not limited to the embodiments described below. Unless otherwise specified, the experimental methods and detection methods described in each embodiment are conventional methods.

[0030] TPU: TUP powder was purchased from Yuke Xerox Plastics Products Co., Ltd., with an average particle size of 50μm to 80μm.

[0031] The polydimethylsiloxane-modified polyurethane and the hydroxyl-terminated polydimethylsiloxane-modified polyurethane are self-made in a laboratory, and the preparation process is as follows: 9 g of IPDI, 10 g of PTMG, and 2.3 g of PDMS are weighed and sequentially added into a 250 mL three-necked flask, then DBTDL is added, the oil bath is heated to 80°C at a stirring speed of 200 rpm, and the reaction is carried out for 3 h; when the temperature is reduced to 70°C, 1 g of DMPA is added for chain extension, and the reaction is carried out for 2 h; 0.5 g of BDO is added, the temperature is increased to 80°C again for chain extension, and the reaction is carried out for 1 h; the oil bath heating is stopped, and the mixture is cooled to 40°C; 0.8 g of TEA is added, and the neutralization reaction is carried out for 30 min; 60 g of deionized water is added into the reaction mixture, and the reaction is carried out for 30 min at a stirring speed of 2000 rpm; the reaction is completed, and a modified polyurethane emulsion is obtained.

[0032] Example 1

[0033] The present example provides a TPU-based composite material and a preparation method thereof.

[0034] The materials used in the present example are TPU, CNTs, H2SO4, HNO3, C6H8O7, Zr(SO4)2, and deionized water.

[0035] Step one: preparing a TPU part,

[0036] A TPU part is prepared by using FDM 3D printing technology with TPU as a raw material.

[0037] Step two: preparing a CNTs-COOH dispersion,

[0038] (1) CNTs are used as a raw material, and the CNTs are placed in a ball mill, and ball milling is carried out at a speed of 200 pm / min for 60 min;

[0039] (2) H2SO4 and HNO3 are mixed in a volume ratio of 3:1, the CNTs are dispersed in the mixed acid solution, ultrasonic dispersion is carried out at a power of 300 W for 60 min, mechanical stirring is carried out at a speed of 300 rpm / min for 20 min at room temperature, and a CNTs mixed solution is obtained;

[0040] (3) The CNTs mixed solution is taken for suction filtration, the suction filtration product is washed with deionized water three times, and vacuum drying is carried out at 60°C for 12 h to obtain CNTs-COOH;

[0041] (4) The CNTs-COOH is taken, deionized water is added, a CNTs-COOH solution with a solid content of 10% is prepared, ultrasonic dispersion is carried out at a power of 300 W for 60 min, and a CNTs-COOH dispersion is obtained.

[0042] Step three: preparing CNTs-COOH / TPU,

[0043] (1) Dilute the solid content of the CNTs-COOH dispersion to 1%, take 8% of the mass of the TPU part of the CNTs-COOH dispersion, ultrasonically disperse for 30 min at a power of 300 W, and mechanically stir at a speed of 300 rpm / min for 20 min;

[0044] (2) Use a gradient temperature low-temperature dyeing process, and the process conditions are as follows: bath ratio 1:20, temperature rising rate 2 ℃ / min, temperature rising from room temperature to 80 ℃, 85 ℃, 90 ℃, and 95 ℃, respectively, and the holding time is 40 min after reaching the specified temperature of 80 ℃, 85 ℃, 90 ℃, and 95 ℃, respectively. The CNTs-COOH is compounded with the TPU part by using an infrared dyeing machine, and then washed with water and dried in a convection oven for 12 h to prepare the CNTs-COOH / TPU composite material.

[0045] In this embodiment, the strain tensile image and the resistivity image of the prepared CNTs-COOH / TPU composite material are as shown in Figure 1 .

[0046] Step four: preparation of Zr / CNTs-COOH / TPU,

[0047] Add 2 g of C6H8O7 and 50 mL of deionized water, and 0.6% of TPU mass of Zr(SO4)2, prepare an acid bath with a pH value of 2.5, add the CNTs-COOH / TPU composite material to the Zr(SO4)2 acid bath, mechanically stir at a speed of 100 rpm / min for 10 min, and dry in a convection oven for 12 h to prepare the Zr / CNTs-COOH / TPU composite material.

[0048] Step five: surface hydrophobicity treatment of the Zr / CNTs-COOH / TPU composite material,

[0049] Dilute the concentration of the PDMS modified polyurethane emulsion to 5 wt%, repeat the spin-spraying operation three times, then place the composite material prepared in step four in a conical flask, run at a temperature of 20 ℃ and a speed of 200 rpm / min for 30 min on a shaking table, and dry in a convection oven for 4 h to endow the composite material with hydrophobic properties, thereby obtaining the TPU-based composite material.

[0050] Example 2

[0051] This example provides a conventional method for preparing a TPU-based composite material, which is different from the preparation method of the present application.

[0052] The materials used in this embodiment are TPU, CNTs, H2SO4, HNO3, C6H8O7, Zr(SO4)2, and deionized water.

[0053] Step one: preparing TPU parts,

[0054] Using TPU as raw material, the FDM 3D printing technology is used to prepare the TPU parts.

[0055] Step two: preparing CNTs-COOH dispersion liquid,

[0056] (1) Taking CNTs as raw material, putting CNTs in the ball mill, ball milling for 60 min at the speed of 200 pm / min;

[0057] (2) Mixing H2SO4 and HNO3 according to the volume ratio of 3:1, dispersing CNTs in the mixed solution of acid, ultrasonic dispersion for 60 min under the power of 300 W, mechanical stirring at the speed of 300 rpm / min for 20 min at room temperature, to obtain CNTs mixed solution;

[0058] (3) Taking CNTs mixed solution for suction filtration, washing the suction filtration product with deionized water for three times, drying in a vacuum drying box at 60℃ for 12 h, to obtain CNTs-COOH;

[0059] (4) Taking CNTs-COOH, adding deionized water, preparing CNTs-COOH solution with solid content of 10%, ultrasonic dispersion treatment for 60 min under the power of 300 W, to obtain CNTs-COOH dispersion liquid.

[0060] Step three: preparing CNTs-COOH / TPU,

[0061] (1) Diluting the solid content of CNTs-COOH dispersion liquid to 1%, respectively taking 2%, 4%, 6%, 8%, 10% of CNTs-COOH dispersion liquid of the mass of TPU parts, ultrasonic dispersion for 30 min under the power of 300 W, mechanical stirring at the speed of 300 rpm / min for 20 min;

[0062] (2) Immersing the 3D printed TPU parts in the CNTs-COOH dispersion liquid, using a magnetic stirrer for stirring while heating, respectively heating to 80℃, 85℃, 90℃, 95℃ of the temperature of the dispersion liquid, using a roller to uniformly roll the TPU parts, drying in a convection oven for 12 h, to prepare CNTs-COOH / TPU composite material.

[0063] Among them, the strain tensile image and the resistivity image of the CNTs-COOH / TPU composite material prepared in the embodiment are as shown in Figure 2 .

[0064] Step four: preparing Zr / CNTs-COOH / TPU,

[0065] Zr / CNTs-COOH / TPU composite material was prepared by adding 2 g C6H8O7, 50 mL deionized water, 0.6% Zr(SO4)2 of TPU mass, preparing an acid bath with pH value of 2.5, adding the CNTs-COOH / TPU composite material into the Zr(SO4)2 acid bath, mechanically stirring at 100 rpm / min for 10 min, and drying in a convection oven for 12 h.

[0066] Step five: surface hydrophobicity treatment of Zr / CNTs-COOH / TPU composite material,

[0067] The concentration of the diluted PDMS modified polyurethane emulsion was 5 wt%, the spin-spraying operation was repeated three times, the composite material prepared in step four was placed in a conical flask, the temperature was 20°C, the shaking bed was operated at 200 rpm / min, and the operation time was 30 min, and the composite material was dried in a convection oven for 4 h to prepare a hydrophobic Zr / CNTs-COOH / TPU composite material, i.e. a 3D printing formed TPU-based composite material.

[0068] Example 3

[0069] The present example provides a TPU-based composite material and a preparation method thereof.

[0070] The materials used in the present embodiment are TPU, CNTs, H2SO4, HNO3, C6H8O7, Zr(SO4)2, and deionized water.

[0071] Step one: preparation of TPU parts,

[0072] TPU parts were prepared by using FDM 3D printing technology with TPU as raw material.

[0073] Step two: preparation of CNTs-COOH dispersion,

[0074] (1) CNTs were used as raw material and placed in a ball mill, and ball milled at a speed of 200 rpm / min for 60 min;

[0075] (2) H2SO4 and HNO3 were mixed in a volume ratio of 3:1, CNTs were dispersed in the mixed acid solution, ultrasonic dispersion was carried out at a power of 300 W for 60 min, and mechanical stirring was carried out at a speed of 300 rpm / min at room temperature for 20 min to obtain a CNTs mixed solution;

[0076] (3) The CNTs mixed solution was taken for suction filtration, the suction filtration product was washed with deionized water three times, and vacuum drying was carried out at 60°C for 12 h to obtain CNTs-COOH;

[0077] (4) Take CNTs-COOH, add deionized water, prepare a CNTs-COOH solution with a solid content of 10%, and ultrasonically disperse for 60 min under a power of 300 W to obtain a CNTs-COOH dispersion.

[0078] Step three: preparation of CNTs-COOH / TPU,

[0079] (1) Dilute the solid content of the CNTs-COOH dispersion to 1%, and take 2%, 4%, 6%, 8%, and 10% of the CNTs-COOH dispersion of the mass of the TPU product, respectively, and ultrasonically disperse for 30 min under a power of 300 W, and mechanically stir at a speed of 300 rpm / min for 20 min;

[0080] (2) Gradient temperature dyeing process is used, and the process conditions are as follows: bath ratio 1:20, temperature rising rate 1 ℃ / min, temperature rising from room temperature to 90 ℃, holding time 60 min after reaching the specified temperature of 90 ℃, compounding CNTs-COOH and TPU product by an infrared dyeing machine, and then washing, drying in a convection oven for 12 h to prepare CNTs-COOH / TPU composite material.

[0081] In this embodiment, the strain tensile image and the resistivity image of the prepared CNTs-COOH / TPU composite material are as shown in Figure 3 .

[0082] Step four: preparation of Zr / CNTs-COOH / TPU,

[0083] Add 2 g of C6H8O7, 50 mL of deionized water, and 0.6% of Zr(SO4)2 of the mass of the TPU to prepare an acid bath with a pH value of 2.5, add the CNTs-COOH / TPU composite material to the Zr(SO4)2 acid bath, mechanically stir at a speed of 100 rpm / min for 10 min, and dry in a convection oven for 12 h to prepare a Zr / CNTs-COOH / TPU composite material.

[0084] Step five: surface hydrophobicity treatment of Zr / CNTs-COOH / TPU composite material,

[0085] Dilute the concentration of the PDMS-modified polyurethane emulsion to 5 wt%, repeat the spin-spraying operation three times, place the composite material prepared in step four in a conical flask, run at a temperature of 20 ℃ and a speed of 200 rpm / min for 30 min on a shaking bed, and dry in a convection oven for 4 h to prepare a hydrophobic Zr / CNTs-COOH / TPU composite material, i.e., a 3D-printed TPU-based composite material.

[0086] Example 4

[0087] The present example provides a TPU-based composite material and a preparation method thereof

[0088] The materials used in the present embodiment are TPU, CNTs, H2SO4, HNO3, C6H8O7, Zr(SO4)2, and deionized water.

[0089] Step one: preparing a 3D-printed TPU part,

[0090] Using TPU as the raw material, a 3D-printed TPU part is prepared by FDM 3D printing technology.

[0091] Step two: preparing a CNTs-COOH dispersion,

[0092] (1) Using CNTs as the raw material, the CNTs are placed in a ball mill and ball-milled at a speed of 200 pm / min for 60 min;

[0093] (2) H2SO4 and HNO3 are mixed in a volume ratio of 3:1, the CNTs are dispersed in the mixed acid solution, and ultrasonic dispersion is performed at a power of 300 W for 60 min, and mechanical stirring is performed at a speed of 300 rpm / min for 20 min at room temperature to obtain a CNTs mixed solution;

[0094] (3) The CNTs mixed solution is taken for suction filtration, the suction filtration product is washed with deionized water three times, and vacuum drying is performed at 60°C for 12 h to obtain CNTs-COOH;

[0095] (4) Take CNTs-COOH, add deionized water, prepare a CNTs-COOH solution with a solid content of 10%, and ultrasonic dispersion is performed at a power of 300 W for 60 min to obtain a CNTs-COOH dispersion.

[0096] Step three: preparing CNTs / TPU,

[0097] (1) Dilute the solid content of the CNTs-COOH dispersion to 1%, take 8% of the mass of TPU CNTs-COOH dispersion, ultrasonic dispersion is performed at a power of 300 W for 30 min, and mechanical stirring is performed at a speed of 300 rpm / min for 20 min;

[0098] (2) Gradient temperature low-temperature dyeing process is used, and the process conditions are as follows: bath ratio 1:20, temperature rising rate 2°C / min, temperature rising from room temperature to 90°C, holding time 40 min after reaching the specified temperature of 90°C, CNTs-COOH and TPU parts are compounded by an infrared dyeing machine, and then washed with water, dried in a convection oven for 12 h to prepare a CNTs-COOH / TPU composite material.

[0099] Step four: preparing Zr / CNTs-COOH / TPU,

[0100] Add 2g C6H8O7, 50mL deionized water, Zr(SO4)2 with TPU mass of 0.2%, 0.4%, 0.6%, 0.8%, 1.0% respectively, prepare an acid bath with pH value of 2.5, add the CNTs-COOH / TPU composite material into the Zr(SO4)2 acid bath, mechanically stir at 100rpm / min for 10min, dry in a convection oven for 12h to prepare the Zr / CNTs-COOH / TPU composite material.

[0101] Step five: surface hydrophobicity treatment of the Zr / CNTs-COOH / TPU composite material,

[0102] Dilute the concentration of the PDMS modified polyurethane emulsion to 5wt%, repeat the spin-spraying operation three times, then place the composite material prepared in step four in a conical flask, run at a temperature of 20℃ and a shaking bed speed of 200rpm / min for 30min, dry in a convection oven for 4h to endow the composite material with hydrophobicity, and thus obtain the TPU-based composite material.

[0103] The TPU-based composite material of the present example can be prepared according to the above steps.

[0104] Example 5

[0105] The present example provides a TPU-based composite material and a preparation method thereof.

[0106] The materials used in the present example are TPU, CNTs, H2SO4, HNO3, C6H8O7, Zr(SO4)2, deionized water.

[0107] Step one: preparation of TPU parts,

[0108] Using TPU as raw material, the FDM 3D printing technology is used to prepare the formed TPU parts.

[0109] Step two: preparation of CNTs-COOH dispersion,

[0110] (1) Using CNTs as raw material, place the CNTs in a ball mill and ball mill at a speed of 200pm / min for 60min;

[0111] (2) Mix H2SO4 and HNO3 according to a volume ratio of 3:1, disperse the CNTs in the mixed acid solution, ultrasonically disperse at a power of 300W for 60min, and mechanically stir at a speed of 300rpm / min at room temperature for 20min to obtain a CNTs mixed solution;

[0112] (3) Take the CNTs mixed solution to perform suction filtration, rinse the suction filtration product with deionized water three times, and dry in a vacuum drying box at 60°C for 12h to obtain CNTs-COOH;

[0113] (4) Take CNTs-COOH, add deionized water to prepare a CNTs-COOH solution with a solid content of 10%, and perform ultrasonic dispersion treatment for 60min under the condition of a power of 300W to obtain a CNTs-COOH dispersion liquid.

[0114] Step three: preparation of CNTs-COOH / TPU,

[0115] (1) Dilute the solid content of the CNTs-COOH dispersion liquid to 1%, take 8% of the CNTs-COOH dispersion liquid by mass of TPU, perform ultrasonic dispersion for 30min under the condition of a power of 300W, and mechanically stir at a speed of 300rpm / min for 20min;

[0116] (2) Adopt gradient temperature low-temperature dyeing process, and the process conditions are as follows: bath ratio 1:20, temperature rising rate 2°C / min, temperature rising from room temperature to 90°C, holding time 40min after reaching the specified temperature of 90°C, composite CNTs-COOH and TPU parts through an infrared dyeing machine, and then perform water washing and drying in a convection oven for 12h to prepare CNTs-COOH / TPU composite material.

[0117] Step four: preparation of Zr / CNTs-COOH / TPU,

[0118] Add 5g, 4g, 1g, 0.5g, and 0.1g C6H8O7 respectively, 50mL deionized water, and 0.6% of Zr(SO4)2 by mass of TPU to prepare an acid bath with pH values of 2, 2.5, 3, 3.5, and 4 respectively, add the CNTs-COOH / TPU composite material to the Zr(SO4)2 acid bath, mechanically stir at a speed of 100rpm / min for 10min, and dry in a convection oven for 12h to prepare Zr / CNTs-COOH / TPU composite material.

[0119] Step five: hydrophobic treatment of the surface of the Zr / CNTs-COOH / TPU composite material,

[0120] Dilute the concentration of the PDMS-modified polyurethane emulsion to 5wt%, repeat the spin-spraying operation three times, place the composite material prepared in step four in a conical flask, run at a temperature of 20°C and a speed of 200rpm / min for 30min on a shaking table, and dry in a convection oven for 4h to endow the composite material with hydrophobic properties, thereby obtaining a TPU-based composite material.

[0121] The TPU-based composite material of the present embodiment can be prepared according to the above steps.

[0122] The strain tensile image and resistivity image of the Zr / CNTs-COOH / TPU composite material prepared in this embodiment are as shown in Figure 7 .

[0123] Example 6

[0124] The present example provides a TPU-based composite material and a preparation method thereof.

[0125] The materials used in this embodiment are TPU, CNTs, H2SO4, HNO3, C6H8O7, Zr(SO4)2, and deionized water.

[0126] Step one: preparing a TPU part,

[0127] Using TPU as the raw material, a molded TPU part is prepared by FDM 3D printing technology.

[0128] Step two: preparing a CNTs-COOH dispersion solution,

[0129] (1) Using CNTs as the raw material, the CNTs are placed in a ball mill and ball milled at a speed of 200 pm / min for 60 min;

[0130] (2) H2SO4 and HNO3 are mixed in a volume ratio of 3:1, the CNTs are dispersed in the mixed acid solution, ultrasonic dispersion is performed at a power of 300 W for 60 min, mechanical stirring is performed at a speed of 300 rpm / min for 20 min at room temperature, and a CNTs mixed solution is obtained;

[0131] (3) The CNTs mixed solution is taken for suction filtration, the suction filtration product is washed with deionized water three times, vacuum drying is performed at 60°C for 12 h, and CNTs-COOH is obtained;

[0132] (4) CNTs-COOH is taken, deionized water is added, a CNTs-COOH solution with a solid content of 10% is prepared, ultrasonic dispersion is performed at a power of 300 W for 60 min, and a CNTs-COOH dispersion solution is obtained.

[0133] Step three: preparing CNTs-COOH / TPU,

[0134] (1) The solid content of the CNTs-COOH dispersion solution is diluted to 1%, 8% of the mass of TPU of the CNTs-COOH dispersion solution is taken, ultrasonic dispersion is performed at a power of 300 W for 30 min, and mechanical stirring is performed at a speed of 300 rpm / min for 20 min;

[0135] (2) Gradient temperature low temperature dyeing process was used, and the process conditions were as follows: bath ratio 1:20, temperature rising rate 2°C / min, temperature rising from room temperature to 90°C, holding at 90°C for 40 min, CNTs-COOH was compounded with TPU parts by using an infrared dyeing machine, then water washing, drying in a convection oven for 12 h, and CNTs-COOH / TPU composite material was prepared.

[0136] Step four: preparation of Zr / CNTs-COOH / TPU,

[0137] 2g C6H8O7, 50mL deionized water, 0.6% TPU mass of Zr(SO4)2, and an acid bath with pH value of 2.5 were added, CNTs / TPU composite material was added into the Zr(SO4)2 acid bath, mechanical stirring was performed at a speed of 100 rpm / min for 10 min, drying in a convection oven for 12 h, and Zr / CNTs-COOH / TPU composite material was prepared.

[0138] Step five: surface hydrophobicity treatment of Zr / CNTs-COOH / TPU composite material

[0139] The concentration of the diluted PDMS modified polyurethane emulsion was 5wt%, the spin coating operation was repeated three times, the composite material prepared in step four was placed in a conical flask, the temperature was 20°C, the shaking bed was operated at a speed of 200 rpm / min, and the operation time was 30 min, drying in a convection oven for 4 h, and the composite material was endowed with hydrophobicity, and TPU-based composite material was obtained.

[0140] The super-depth microscope image of the CNTs-COOH / TPU composite material prepared in this example is shown in Figure 4 The scanning electron microscope image of the 3D printing TPU part is shown in Figure 5 The scanning electron microscope image of the Zr / CNTs-COOH / TPU composite material prepared in this example is shown in Figure 6 The sensing image of the CNTs-COOH / TPU and Zr / CNTs-COOH / TPU composite materials prepared in this example is shown in Figure 8 The water contact angle test of the TPU-based composite material prepared in this example is shown in Figure 9

[0141] Example 7

[0142] The present example provides a TPU-based composite material and a preparation method thereof.

[0143] The materials used in this example are TPU, Gr, H2 S O4, NaNO3, KMnO4, H2O2, HCl, C6H8O7, Al2(SO4)3, and deionized water.

[0144] ​Step one: preparing TPU parts,

[0145] Using FDM 3D printing technology to prepare TPU parts.

[0146] Step two: preparing GO dispersion liquid,

[0147] 98% H2SO4 was added to a 500 mL reaction bottle in an ice water bath, and natural expanded graphite powder and NaNO3 were mixed under stirring conditions at a mass ratio of 2:1, and the reaction was maintained at about 4℃ for 1h;

[0148] Then, appropriate amount of KMnO4 was added in several times, and the reaction temperature was controlled not to exceed 20℃, and the reaction was carried out under stirring conditions for 2h (the color changed from black to dark green);

[0149] The temperature was raised to about 35℃, and the reaction was carried out under stirring conditions for 2h, then 100 mL of deionized water was slowly added, and the stirring was continued for 30 min (the reaction solution was yellow), then 100 mL of deionized water was added for dilution, and the reaction was continued for 2h, finally cooled to room temperature, and H2O2 was added constantly to remove residual oxidizing agent until the solution turned bright yellow;

[0150] (4) hot filtration, washing with 5% dilute HCl solution and deionized water until no-SO4 2- was detected in the filtrate, finally the filter cake was dispersed in deionized water under the condition of 300W ultrasonic for 60 min, and GO water dispersion liquid was obtained.

[0151] Step three: preparing GO / TPU,

[0152] (1) dilute the solid content of GO dispersion liquid to 1%, take 8% GO dispersion liquid of TPU mass, and disperse under the condition of power 300W for 30 min, and mechanical stirring at 300rpm / min for 20 min;

[0153] (2) using gradient temperature low temperature dyeing process, the process conditions are as follows: bath ratio 1:20, temperature rising rate 2℃ / min, temperature rising from room temperature to 90℃, holding time 40 min after reaching 90℃, GO and TPU parts were compounded by infrared dyeing machine, then washed, dried in convection oven for 12h, and GO / TPU composite material was prepared.

[0154] Step four: preparing Al / GO / TPU,

[0155] Add 1 g of C6H8O7, 50 mL of deionized water, 0.6% of TPU mass of Al2(SO4)3, prepare an acidic bath with a pH value of 3, add the GO / TPU composite material to the Al2(SO4)3 acidic bath, mechanically stir at a speed of 100 rpm / min for 10 min, dry in a convection oven for 12 h to obtain the Al / GO / TPU composite material.

[0156] Step five: hydrophobic treatment of the surface of the Al / GO / TPU composite material,

[0157] Dilute the concentration of the HTPDMS modified polyurethane emulsion to 5 wt%, repeat the spin-spraying operation three times, then place the composite material prepared in step four in a conical flask, operate at a temperature of 20°C and a shaking bed speed of 200 rpm / min for 30 min, dry in a convection oven for 4 h to endow the composite material with hydrophobic properties, and obtain the TPU-based composite material.

[0158] The TPU-based composite material prepared in this example is a composite material with hydrophobic treatment on the surface of the Al / GO / TPU composite material.

[0159] Example 8

[0160] The present example provides a TPU-based composite material and a preparation method thereof.

[0161] The materials used in this example are TPU, Mxene, LiF, HCl, Ti3AlC2, N2, FeCl3, and deionized water.

[0162] Step one: preparation of a TPU part,

[0163] Using TPU as the raw material, a TPU part is prepared by FDM 3D printing technology.

[0164] Step two: preparation of a Mxene dispersion,

[0165] Dissolve 2 g of lithium fluoride in 20 mL of HCl solution with a concentration of 9 mol / L, and stir in an ice bath;

[0166] Add 6% of TPU mass of Ti3AlC2, stir uniformly, and then place in a 40°C oil bath for etching for 48 h. After etching, centrifuge the solution and collect the precipitate, add 0.1 mol / L HCl solution for acid washing, wash with deionized water, and centrifuge to collect the precipitate;

[0167] Add the precipitate to deionized water, move it to a gas washing bottle, connect the N2 gas source for bubbling, and ultrasonically disperse for 2 h under the condition of 300 W;

[0168] Centrifuge the solution and collect the upper liquid to obtain the Mxene solution;

[0169] The obtained Mxene solution was added to deionized water, ultrasonically dispersed at a power of 300 W for 60 min, and mechanically stirred at a speed of 300 rpm / min for 30 min to obtain a MXene dispersion liquid.

[0170] Step three: preparation of MXene / TPU,

[0171] (1) Dilute the solid content of the Mxene dispersion liquid to 1%, take 8% of the mass of TPU Mxene dispersion liquid, ultrasonically disperse at a power of 300 W for 30 min, and mechanically stir at a speed of 300 rpm / min for 20 min;

[0172] (2) Gradient temperature dyeing process was used, and the process conditions were as follows: bath ratio 1:20, temperature rising rate 2℃ / min, temperature rising from room temperature to 90℃, holding time 40 min after reaching the specified temperature of 90℃, Mxene and TPU parts were compounded by infrared dyeing machine, and then washed, dried in a convection oven for 12 h to obtain Mxene / TPU composite material.

[0173] Step four: preparation of Fe / Mxene / TPU,

[0174] 1g C6H8O7 and 50mL deionized water were added, C6H8O7, deionized water, 0.6% of the mass of TPU FeCl3, an acid bath with a pH value of 3 was prepared, the Mxene / TPU composite material was added to the FeCl3 acid bath, mechanically stirred at a speed of 100 rpm / min for 10 min, dried in a convection oven for 12 h to obtain Fe / Mxene / TPU composite material.

[0175] Step five: hydrophobic treatment of Fe / Mxene / TPU surface,

[0176] The concentration of the HTPDMS modified polyurethane emulsion was diluted to 5wt%, the spin coating operation was repeated three times, and then the composite material prepared in step four was placed in a conical flask, the temperature was 20℃, the shaker was operated at a speed of 200 rpm / min for 30 min, and the composite material was dried in a convection oven for 4 h to obtain a TPU-based composite material with hydrophobic properties.

[0177] The TPU-based composite material prepared in this example is a composite material with hydrophobic treatment on the surface of Fe / Mxene / TPU.

[0178] Example 9

[0179] The present example provides a TPU-based composite material and a preparation method thereof.

[0180] The materials used in this example are TPU, Mxene, LiF, HCl, Ti3AlC2, N2, Ce2(SO4)3, and deionized water.

[0181] Step one: preparing TPU parts,

[0182] Using TPU as raw material, using FDM 3D printing technology to prepare TPU parts.

[0183] Step two: preparing Mxene dispersion,

[0184] Dissolve 2g lithium fluoride in 20mL of 9mol / L HCl solution, ice bath stirring;

[0185] Add 6% of TPU mass Ti3AlC2, stir evenly and place in 40℃ oil bath for 48h. After etching, centrifuge the solution and collect the precipitate, add 0.1mol / L HCl solution for acid washing, wash with deionized water, centrifuge and collect the precipitate;

[0186] Add the precipitate to deionized water and move it to a gas washing bottle, connect the N2 gas source for bubbling, ultrasonic dispersion under the condition of 300W for 2h;

[0187] Centrifuge the solution and collect the upper liquid to obtain Mxene solution;

[0188] Add the obtained Mxene solution to deionized water, ultrasonic dispersion under the condition of 300W for 60min, mechanical stirring at 300rpm / min for 30min, to obtain Mxene dispersion.

[0189] Step three: preparing Mxene / TPU,

[0190] (1) Dilute the solid content of Mxene dispersion to 1%, take 8% of TPU mass Mxene dispersion, ultrasonic dispersion under the condition of 300W for 30min, mechanical stirring at 300rpm / min for 20min;

[0191] (2) Using gradient temperature low temperature dyeing process, process conditions are as follows: bath ratio 1:20, temperature rising rate 2℃ / min, temperature from room temperature to 90℃, after reaching 90℃ specified temperature, holding time 40min, through infrared dyeing machine, Mxene and TPU parts are compounded, then washed with water, dried in convection oven for 12h, to obtain Mxene / TPU composite material.

[0192] Step four: preparing Ce / Mxene / TPU,

[0193] Add 2g C6H8O7, 50mL deionized water, Ce2(SO4)3 of 0.6% of the mass of TPU, prepare an acid bath with a pH value of 2.5, add the Mxene / TPU composite material to the Ce2(SO4)3 acid bath, mechanically stir at a speed of 100 rpm / min for 10 min, dry in a convection oven for 12 h to obtain a Ce / MXene / TPU composite material.

[0194] Step five: hydrophobic treatment of the surface of the Ce / Mxene / TPU composite material,

[0195] Dilute the HTPDMS modified polyurethane emulsion to a concentration of 5wt%, repeat the spin-spraying operation three times, then place the composite material prepared in step four in a conical flask, operate at a temperature of 20℃ and a shaking bed speed of 200 rpm / min for 30 min, dry in a convection oven for 4 h to endow the composite material with hydrophobic properties, and obtain a TPU-based composite material.

[0196] The TPU-based composite material prepared in this example is a Ce / Mxene / TPU composite material with a hydrophobic surface.

[0197] Example 10

[0198] The present example provides a TPU-based composite material and a method for preparing the same.

[0199] The materials used in this example are TPU, Mxene, LiF, HCl, Ti3AlC2, N2, LaCl3, and deionized water.

[0200] Step one: preparation of a TPU part,

[0201] Using TPU as the raw material, a TPU part is prepared by FDM 3D printing technology.

[0202] Step two: preparation of a Mxene dispersion,

[0203] Dissolve 2g of lithium fluoride in 20mL of HCl solution with a concentration of 9mol / L, and stir in an ice bath.

[0204] Add Ti3AlC2 of 6% of the mass of TPU, stir uniformly, and then place in a 40℃ oil bath for etching for 48h. After etching, centrifuge the solution and collect the precipitate, add 0.1mol / L HCl solution for acid washing, wash with deionized water, and centrifuge to collect the precipitate.

[0205] Add the precipitate to deionized water and move it to a gas washing bottle, connect the N2 gas source for bubbling, and ultrasonically disperse for 2h under the condition of 300W.

[0206] Centrifuge the above solution and collect the upper liquid to obtain a Mxene solution.

[0207] The obtained Mxene solution was added to deionized water, ultrasonic dispersion was performed under the condition of power 300 W for 60 min, and mechanical stirring was performed at a speed of 300 rpm / min for 30 min to obtain a Mxene dispersion liquid.

[0208] Step three: preparation of Mxene / TPU,

[0209] (1) The solid content of the Mxene dispersion liquid was diluted to 1%, and a dispersion liquid of 8% Mxene by mass of TPU was taken, ultrasonic dispersion was performed under the condition of power 300 W for 30 min, and mechanical stirring was performed at a speed of 300 rpm / min for 20 min.

[0210] (2) A gradient temperature low-temperature dyeing process was used, and the process conditions were as follows: bath ratio 1:20, temperature rising rate 2 ℃ / min, temperature rising from room temperature to 90 ℃, holding time 40 min after reaching the specified temperature of 90 ℃, Mxene and TPU parts were compounded by an infrared dyeing machine, and then water washing and convection oven drying were performed for 12 h to prepare a Mxene / TPU composite material.

[0211] Step four: preparation of La / Mxene / TPU,

[0212] 1 g of C6H8O7 and 50 mL of deionized water were added, 0.6% of LaCl3 by mass of TPU was prepared, an acid bath with a pH value of 3 was prepared, the Mxene / TPU composite material was added to the LaCl3 acid bath, mechanical stirring was performed at a speed of 100 rpm / min for 10 min, and convection oven drying was performed for 12 h to prepare a La / Mxene / TPU composite material.

[0213] Step five: hydrophobic treatment of La / Mxene / TPU surface,

[0214] The concentration of the HTPDMS modified polyurethane emulsion was diluted to 5 wt%, the spin-spraying operation was repeated three times, the composite material prepared in step four was placed in a conical flask, the temperature was 20 ℃, the shaking bed was operated at a speed of 200 rpm / min for 30 min, and convection oven drying was performed for 4 h to endow the composite material with hydrophobic properties. Thus, a TPU-based composite material was obtained.

[0215] The TPU-based composite material prepared in this example is a composite material with hydrophobic treatment on the surface of La / Mxene / TPU.

[0216] Example 11

[0217] This example is a performance test of a TPU-based composite material and an intermediate product thereof

[0218] The performance of the composite materials and intermediate products prepared under different conditions was tested. The mechanical properties of the composite materials were analyzed using a universal tensile testing machine; the electrical conductivity was analyzed using a four-probe resistivity tester; the sensing performance was analyzed using an electrochemical workstation. The sensing performance was determined by observing the change amplitude of the composite materials under the bending action at different angles of 30°, 90°, and 150°. The dispersion of CNTs was tested using scanning electron microscope images and 3D images. The performance test results are as follows:

[0219] (1) Conductivity and mechanical property test results

[0220] The intermediate product CNTs-COOH / TPU of the TPU-based composite material prepared in Example 1 was subjected to mechanical property and conductivity tests. The mechanical property test results are shown in Figure 1 (a). The CNTs / TPU composite material with a TPU mass of 8% had little effect on the overall strain tensile properties of the CNTs-COOH / TPU composite material under different temperature gradients. The results showed that the addition of CNTs within a specific temperature range had low sensitivity to the mechanical properties of the CNTs-COOH / TPU composite material, indicating that the CNTs were firmly combined with the TPU parts and had good mechanical properties. The conductivity test results are shown in Figure 1 (b). The CNTs-COOH / TPU composite material had a resistivity of 75.2 Ω·cm at a specific temperature of 90°C. This indicated that the CNTs-COOH / TPU composite material exhibited good conductivity.

[0221] The intermediate product CNTs-COOH / TPU of the TPU-based composite material prepared in Example 2 was subjected to mechanical property and conductivity tests. The mechanical property test results are shown in Figure 2 (a). The CNTs / TPU composite material with a TPU mass of 8% had little effect on the overall strain tensile properties of the CNTs-COOH / TPU composite material under different temperature gradients. The results showed that the addition of CNTs within a specific temperature range had low sensitivity to the mechanical properties of the CNTs-COOH / TPU composite material, indicating that the CNTs were firmly combined with the TPU parts and had good mechanical properties. The conductivity test results are shown in Figure 2 (b). The CNTs-COOH / TPU composite material had a resistivity of 246.46 Ω·cm at a specific temperature of 90°C. This indicated that the CNTs-COOH / TPU composite material exhibited good conductivity.

[0222] Example 1 adopts gradient temperature process to prepare TPU composite material, and Example 2 adopts conventional process to prepare TPU composite material. Through data comparison, the mechanical properties of CNTs-COOH / TPU composite materials prepared by the two processes are not much different, but the conductivity of CNTs-COOH / TPU composite material prepared by gradient temperature process is significantly improved compared with conventional process.

[0223] The mechanical properties and conductivity of the intermediate product CNTs-COOH / TPU of the TPU-based composite material prepared in Example 3 are tested. The mechanical property test results are shown in Figure 3 (a). At a temperature of 90°C, the mechanical properties of TPU composite materials with different amounts of CNTs. Compared with the TPU parts formed by 3D printing, the overall strain tensile properties of CNTs-COOH / TPU composite materials are almost unaffected under different amounts of CNTs. The results show that the addition of CNTs and the change of temperature within a certain range have low sensitivity to the mechanical properties of the composite material, indicating that CNTs are firmly combined with the TPU parts and have good mechanical properties. The conductivity test results are shown in Figure 3 (b). At a temperature of 90°C, the conductivity of CNTs-COOH / TPU composite materials with different amounts of CNTs. From the data in the figure, it can be clearly observed that when the amount of CNTs is 8% of the mass of TPU, the resistivity of CNTs-COOH / TPU composite material is significantly reduced to 75.2 Ω·cm, which shows that the CNTs-COOH / TPU composite material exhibits good conductivity.

[0224] The mechanical properties and conductivity of the TPU-based composite material Zr / CNTs-COOH / TPU prepared in Example 5 are tested. The mechanical property test results are shown in Figure 7 (a). At a temperature of 90°C, the mechanical properties of TPU composite materials with 8% CNTs and 0.6% Zr(SO4)2 of TPU mass in different pH value acid baths. Compared with the intermediate product CNTs-COOH / TPU prepared in Example 1 and Example 3, the strain tensile properties are almost unchanged. The results show that the introduction of transition metal ions also indicates that the composite material has good mechanical properties. The conductivity test results are shown in Figure 7 (b). At a temperature of 90°C, the conductivity of TPU composite materials with 8% CNTs and 0.6% Zr(SO4)2 of TPU mass in different pH value acid baths. Compared with the intermediate product CNTs-COOH / TPU prepared in Example 1 and Example 3, the conductivity is improved. The results show that the introduction of transition metal ions improves the conductivity of the composite material.

[0225] (2) Results of CNT dispersion test

[0226] Super depth-of-field microscopy image of the intermediate product CNTs-COOH / TPU of the TPU-based composite material prepared in Example 6, as shown. Figure 4 As shown. Figure 4 As shown in (a), CNTs-COOH are uniformly distributed on the surface of the CNTs-COOH / TPU composite material; as Figure 4 As shown in (b), this is a 3D model of the CNTs-COOH / TPU composite material, where CNTs-COOH are uniformly distributed in TPU parts of varying thicknesses. Scanning electron microscope (SEM) images of the 3D-printed TPU parts at different magnifications are shown below. Figure 5 As shown; Scanning electron microscope (SEM) images of the TPU-based composite intermediate product CNTs-COOH / TPU prepared in Example 6 at different magnifications, as shown. Figure 6 As shown, CNTs are relatively evenly dispersed in 3D printed TPU parts.

[0227] (3) Sensor performance test results

[0228] The TPU-based composite material prepared in Example 6 was subjected to sensing performance testing. The sensing performance test results are as follows: Figure 8 As shown in (a), the CNTs-COOH / TPU composite material exhibits approximately 40%, 50%, and 60% sensitivity at bending angles of 30°, 90°, and 150°, respectively; Figure 8 As shown in (b), the Zr / CNTs-COOH / TPU composite material exhibits approximately 70%, 90%, and 120% sensitivity at bending angles of 30°, 90°, and 150°, respectively. This indicates that the composite material possesses good sensing performance, and the introduction of transition metal ions further enhances its sensing performance.

[0229] The hydrophobicity test results of the TPU-based composite material prepared in Example 6 are as follows: Figure 9 As shown in (a), the water contact angle of the 3D-printed TPU-based composite material reaches 138.8°; Figure 9 As shown in (b), the water contact angle of the 3D-printed TPU-based composite material reached 141.5°, demonstrating excellent hydrophobic properties. This is due to the combined effect of CNTs and hydrophobic materials on the surface of the TPU part, including reducing surface energy, enhancing interlayer bonding, and generating synergistic effects. These effects work together on the surface of the composite material, giving it excellent hydrophobic properties and a long service life. The slight differences in water contact angle are due to variations in the sample surfaces, resulting in minor differences in the water contact angle test results. Furthermore, the hydrophobic treatment of the composite material has minimal impact on its electrical conductivity and sensing properties.

[0230] As described above, the application can be realized well, the above-mentioned embodiments are only used to describe the preferred embodiments of the application, and do not limit the scope of the application, and various changes and improvements of the technical solutions of the application made by those skilled in the art without departing from the design spirit of the application should fall within the scope of protection of the application.

Claims

1. A process for the preparation of a TPU-based composite material, characterized in that, The method comprises the following steps: S1, providing a TPU part prepared by a fused deposition modeling 3D printing technology; S2, providing a dispersion liquid containing a nano-conductive material, the nano-conductive material being selected from one or more of carbon nanotubes, graphene, Mxene; S3, immersing the TPU part in the dispersion liquid for temperature dyeing treatment; the temperature dyeing treatment is: increasing the temperature from room temperature to 80-95℃ at a temperature increasing rate of 1-2℃ / min, and keeping the temperature at 80-95℃ for 40-60 min; S4. The material treated in step S3 is placed in an acidic bath for further treatment. The acidic bath contains a mixture selected from Zr(SO4)2, Al2(SO4)3, FeCl3, Ce2(SO4)3, and LaCl3. 3- At least one metal salt in the acid bath, wherein the pH value of the acid bath is 2 to 4; S5, performing surface hydrophobic treatment on the material treated in step S4, the surface hydrophobic treatment using polydimethylsiloxane modified polyurethane and / or hydroxyl-terminated polydimethylsiloxane modified polyurethane as a treating agent.

2. The production method according to claim 1, characterized by, In step S2, the nano-conductive material is used in an amount of 2-10% of the mass of the TPU part.

3. The preparation method according to claim 1, characterized in that, In step S2, before the dispersion liquid is compounded with the TPU part, the dispersion liquid is subjected to ultrasonic and mechanical stirring treatment; the power of the ultrasonic is 300-500 W, and the time is 30-60 min; the rotating speed of the mechanical stirring is 100-500 rpm / min, and the time is 10-30 min.

4. The method of claim 1, wherein, In step S5, the concentration of the treating agent is 2-5% by mass.

5. A TPU-based composite material, characterized in that, Prepared by the preparation method of any one of claims 1-4.

Images