Preparation technology of self-energized photo-thermal azobenzene fiber
By introducing azobenzene and liquid metal silicone tubes into thermoplastic polyurethane elastomers, TPU@Azo-SR@LMs fibers with core sheath structure were prepared, which solved the low energy storage capacity and insufficient light conversion rate of existing flexible thermal management fabrics. The problem is that efficient energy collection and human heat management are achieved, improving the durability and safety of fibers.
Patent Information
- Application Number
- CN202311029697.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-08-16
- Publication Date
- 2025-02-21
AI Technical Summary
The existing flexible thermal management fabrics have low energy storage capacity under low load levels and limited solid-state isomerization yields, and the light conversion rate and material safety are insufficient under broadband ultraviolet light exposure, which limits its practical application.
Azo-loaded thermoplastic polyurethane elastomer (TPU@Azo) is used as the sheath layer, and combined with a silicone tube (SR@LMs) injected with liquid metal as the core layer, TPU@Azo-SR@LMs fibers with core sheath structure are prepared. . The fiber not only has the function of friction nanogenerator (TENG) for energy collection and sensing, but also has the functions of photothermal conversion, energy storage and release.
It realizes efficient energy collection and human body thermal management, improves the energy storage capacity and durability of fibers, enhances stability and safety under broadband ultraviolet light conditions, and expands its application prospects in wearable devices.
Smart Images
Figure CN119491307A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to a preparation technology of a self-powered photothermal azobenzene fiber, which can be used in the field of human intelligent thermal management and belongs to the field of photothermal composite materials. Background Art
[0002] In recent years, technologies such as micro-integration have become increasingly mature, and portable and wearable electronic products have developed rapidly. Functional fabrics have attracted widespread attention due to their advantages such as light weight, flexibility, comfort and breathability, easy processing and integration. Traditional textiles are not always effective in achieving better personal thermal management. Azobenzene photothermal storage and conversion thermal management fabrics have the advantages of good cycle stability and controllable heat storage and release. The development of self-powered, intelligently controlled thermal fabrics that collaborate with the environment for thermal management has broad application prospects.
[0003] Thermal management consumes a large portion of global energy for human thermal comfort and health. Unlike building heating, ventilation, and air conditioning systems, personal thermal management (PTM) focuses on the microenvironment around people that directly affects thermal sensation. Therefore, it shows great potential in reducing energy consumption because it does not require temperature control of the entire room. PTM systems have broad application prospects not only in protecting the human body from cold damage, but also in disease prevention and hyperthermia therapy. Among the recent PTM developments, solar-based PTMs have attracted much attention due to their sustainability and controllability. To date, there have been a few studies on flexible thermal management fabrics, although to the best of our knowledge, none of them focused on PTM applications. Moth-Poulsen et al. prepared a photo-switchable film with high flexibility and durability. However, the low loading level (typically less than 20%) and limited solid-state isomerization yield resulted in relatively low energy storage capacity of flexible MOST devices. Yu et al. impregnated cotton fabric with molten photo-liquidable azobenzene molecules to fabricate a fabric-based MOST device. Despite its high energy density (201 kJ kg), its practical application will be limited by its poor safety and robustness due to the weak interaction between polyester / cellulose and azobenzene. We previously reported a MOST fabric with 4-tetradecacyclyloxyazobenzene as the core material encapsulating solar energy storage microcapsules, which has fast solid-state isomerization and good wear resistance. However, its energy storage capacity is limited due to the low isomerization energy of azobenzene photoswitch. In addition, under broadband UV light (260-380 nm, solar UV region) irradiation, the E-to-Z photoconversion efficiency is only about 70%, because deep UV light (below 300 nm) can cause Z-to-E back conversion and material degradation.
[10] Light sources with narrow wavelength ranges are expensive, and filtering will cause energy waste. Therefore, it is necessary to explore new designs of flexible MOST fabrics to improve their energy storage capacity and durability. Summary of the invention
[0004] The present invention uses a thermoplastic polyurethane elastomer loaded with Azo as a sheath layer (TPU@Azo) and a silicone tube injected with liquid metal (SR@LMs) as a core layer to prepare a thermoplastic polyurethane elastomer@azobenzene-silicone tube@liquid metal (TPU@Azo-SR@LMs) fiber with a core-sheath structure.
[0005] The technical purpose of the present invention is achieved through the following technical solutions.
[0006] A preparation technology of a self-powered photothermal azobenzene fiber is carried out according to the following steps:
[0007] Step 1, Preparation of TPU hollow fibers
[0008] A coaxial wet spinning process was adopted, and a 11 / 14G coaxial needle was used. TPU spinning solution was injected into the No. I port (14G) of the spinneret, and deionized water was injected into the No. II port (11G) of the spinneret. The TPU solution wrapped the deionized water and squeezed out from the spinneret hole and then entered the coagulation bath (deionized water). When the TPU solution reached the critical concentration, it gradually coagulated in the deionized water to form hollow fibers. After soaking in water overnight, the prepared hollow fibers were taken out from the deionized water and freeze-dried to finally obtain dried hollow fibers.
[0009] In step 1, the spinning speed was 0.01 mm s -1 The flow of the TPU solution in the No. I port of the spinneret is the same as that of the deionized water in the No. II port, so that the deionized water continuously exists inside the TPU hollow tube, and at the same time plays a role in accelerating the solidification of the TPU and supporting the shaping of the hollow tube inside.
[0010] Step 2, Preparation of TPU@Azo hollow fibers
[0011] The synthesized azobenzene (Azo) was dissolved in a dichloromethane solvent to obtain an azobenzene solution and poured into a glass container. The prepared TPU hollow fiber was immersed in the azobenzene solution and shaken for 1 minute. The TPU@Azo hollow fiber was obtained after being taken out and dried.
[0012] Step 3, Preparation of SR@LMs fibers
[0013] The purchased hollow silicone tube (SR, inner diameter 0.5 mm, outer diameter 1 mm) was cut into a suitable length. Liquid metal (LMs) was sucked up using a syringe and injected into the SR to obtain conductive SR@LMs fibers.
[0014] In step 3, the resistance of the obtained conductive SR@LMs fiber is 2-10Ω.
[0015] Step 4, Preparation of TPU@Azo-SR@LMs
[0016] 4) The prepared conductive SR is inserted into the prepared TPU@Azo hollow fiber to obtain self-powered photothermal azobenzene fibers (TPU@Azo-SR@LMs).
[0017] The fiber prepared by the present invention has both the function of a friction nanogenerator (TENG) and a thermal management function. TENG can be used as an energy harvesting device and a sensing device. It can effectively collect various types of mechanical energy and effectively monitor signals such as human pulse. The TPU@Azo part can be used as a photothermal conversion, energy storage and release device. In addition, the prepared fiber can be woven into a fabric as a wearable, self-powered, effective photo-energy storage and thermal management fabric to achieve effective human thermal management. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Figure 1 Schematic diagram of the structure of TPU@Azo-SR@LMs fiber.
[0019] Figure 2 The pulse signal at the wrist monitored by TPU@Azo-SR@LMs.
[0020] Figure 3 Temperature change curve of TPU@Azo-SR@LMs fabric under blue light irradiation after UV charging. DETAILED DESCRIPTION
[0021] Three embodiments of the present invention are provided below to further illustrate the present invention, but not to limit the scope of the present invention.
[0022] Example 1
[0023] 1) Preparation of TPU hollow fibers: A coaxial wet spinning process was adopted with a 11 / 14G coaxial needle. TPU spinning solution was injected into the No. I port (14G) of the spinneret, and deionized water was injected into the No. II port (11G) of the spinneret. The TPU solution wrapped the deionized water and squeezed out from the spinneret hole and then entered the coagulation bath (deionized water). When the TPU solution reached the critical concentration, it gradually coagulated in the deionized water to form hollow fibers. After soaking in water overnight, the prepared hollow fibers were taken out of the deionized water and freeze-dried to finally obtain dried hollow fibers.
[0024] 2) Preparation of TPU@Azo: The synthesized azobenzene (Azo) was dissolved in a dichloromethane solvent to obtain an azobenzene solution and poured into a glass container, the prepared TPU hollow fiber was immersed in the azobenzene solution and shaken for 1 min, and then taken out and dried to obtain the TPU@Azo hollow fiber.
[0025] 3) Preparation of SR@LMs fibers: The purchased hollow silicone tube (SR, inner diameter 0.5 mm, outer diameter 1 mm) was cut into appropriate lengths. Liquid metal (LMs) was sucked up using a syringe and injected into the SR to obtain conductive SR@LMs fibers.
[0026] 4) Preparation of TPU@Azo-SR@LMs: The prepared conductive SR was inserted into the prepared TPU@Azo hollow fiber to obtain self-powered photothermal azobenzene fibers (TPU@Azo-SR@LMs).
[0027] Example 2
[0028] 1) Preparation of SR@LMs fibers: The purchased hollow silicone tube (SR, inner diameter 0.5 mm, outer diameter 1 mm) was cut into appropriate lengths. Liquid metal (LMs) was sucked up using a syringe and injected into the SR to obtain conductive SR@LMs fibers.
[0029] 2) Preparation of TPU-SR@LMs fibers: The coaxial wet spinning process was adopted, and a 11 / 14G coaxial needle was used. The TPU spinning solution was injected into the spinneret port I (14G), and the deionized water was injected into the spinneret port II (11G) and introduced
[0030] SR@LMs fiber, TPU solution wrapped deionized water and SR@LMs fiber are extruded from the spinneret and then enter the coagulation bath (deionized water). When the TPU solution reaches the critical concentration, it gradually solidifies in deionized water to form hollow fibers, which are then pulled to obtain incompletely solidified TPU-SR@LMs fibers. After soaking in water overnight, the prepared hollow fibers are taken out of the deionized water for freeze drying, and finally dry TPU-SR@LMs fibers are obtained.
[0031] 3) The synthesized azobenzene (Azo) was dissolved in a dichloromethane solvent to obtain an azobenzene solution and poured into a glass container, the prepared TPU-SR@LMs fiber was immersed in the azobenzene solution and shaken for 1 min, and then taken out and dried to obtain TPU@Azo hollow fiber.
[0032] Example 3
[0033] 1) Preparation of TPU hollow fiber: 13.5 g of TPU was added to a beaker containing 37.5 g of DMF, and the precursor solution was obtained by magnetic stirring at 25°C for 2 h to completely dissolve TPU in DMF, and stirred at room temperature for 6 h to obtain TPU spinning solution. TPU hollow fiber was obtained by wet spinning process.
[0034] 2) Preparation of TPU@Azo: The two ends of the prepared TPU hollow fiber were sealed and immersed in an azobenzene solution to obtain TPU@Azo fiber.
[0035] 3) Preparation of SR@LMs fibers: Liquid metal (LMs) was injected into a purchased hollow silicone tube (SR, inner diameter 0.5 mm, outer diameter 1 mm), and both ends were sealed to obtain conductive SR@LMs fibers.
[0036] 4) Preparation of TPU@Azo-SR@LMs: The prepared conductive SR was inserted into the prepared TPU@Azo hollow fiber to obtain self-powered photothermal azobenzene fibers (TPU@Azo-SR@LMs).
[0037] The present invention is described above by way of example. It should be noted that, without departing from the core of the present invention, any simple deformation, modification or other equivalent replacement that can be made by those skilled in the art without inventive effort falls within the protection scope of the present invention.
Claims
1. A preparation technology of self-powered photothermal azobenzene fiber, its characteristics and The preparation steps are as follows: 1) Preparation of TPU hollow fibers: A coaxial wet spinning process was adopted with a 11 / 14G coaxial needle. TPU spinning solution was injected into the No. I port (14G) of the spinneret, and deionized water was injected into the No. II port (11G) of the spinneret. The TPU solution wrapped the deionized water and squeezed out from the spinneret hole and then entered the coagulation bath (deionized water). When the TPU solution reached the critical concentration, it gradually coagulated in the deionized water to form hollow fibers. After soaking in water overnight, the prepared hollow fibers were taken out of the deionized water and freeze-dried to finally obtain dried hollow fibers. 2) Preparation of TPU@Azo: The synthesized azobenzene (Azo) was dissolved in a dichloromethane solvent to obtain an azobenzene solution and poured into a glass container, the prepared TPU hollow fiber was immersed in the azobenzene solution and shaken for 1 min, and then taken out and dried to obtain the TPU@Azo hollow fiber. 3) Preparation of SR@LMs fibers: The purchased hollow silicone tube (SR, inner diameter 0.5 mm, outer diameter 1 mm) was cut into appropriate lengths. Liquid metal (LMs) was sucked up using a syringe and injected into the SR to obtain conductive SR@LMs fibers. 4) Preparation of TPU@Azo-SR@LMs: The prepared conductive SR was inserted into the prepared TPU@Azo hollow fiber to obtain self-powered photothermal azobenzene fibers (TPU@Azo-SR@LMs).
2. The preparation method according to step 1) in claim 1, characterized in that: The flow of the TPU solution in the No. I port of the spinneret is the same as that of the deionized water in the No. II port, so that the deionized water continuously exists inside the TPU hollow tube, and at the same time plays a role in accelerating the solidification of the TPU and supporting the shaping of the hollow tube inside.
3. The preparation method according to step 2) in claim 1, characterized in that: Before impregnation of the TPU hollow fiber, both ends were sealed with Ecoflex to prevent the Azo solution from entering the tube, causing waste and affecting the electronegativity of TPU.
4. The preparation method according to step 4) of claim 1, characterized in that Its characteristics are TPU hollow fiber and SR@LMs form a single-electrode triboelectric nanogenerator (TENG), in which TPU and SR serve as friction pairs and LMs serve as electrodes. TPU-SR@LMs-based TENG serves as both an energy harvesting device and a sensing device. It can effectively collect various types of mechanical energy and effectively monitor human pulse and other signals.