Electroluminescent magnetic fiber and preparation method thereof

Abstract

The invention discloses an electroluminescent magnetic fiber and a preparation method thereof in the technical field of textile composite materials, the electroluminescent magnetic fiber is a composite fiber, and comprises a core layer, an electroluminescent layer and a conductive layer; wherein the core layer is made of silver nanowires (AgNWs); the electroluminescent layer is a mixture of polyvinylidene fluoride (PVDF), neodymium iron boron (NdFeB), gallium phosphide (GaP) and an organic solvent; and the conductive layer is indium tin oxide (ITO). According to the electroluminescent magnetic fiber provided by the invention, magneto-electricity and electroluminescence are effectively combined, the integration of electroluminescent devices is realized, and the electroluminescent magnetic fiber has good conductivity and magnetic response performance and can meet practical application.

Description

Technical Field

[0001] The invention relates to the technical field of textile composite materials, and in particular to an electroluminescent magnetic fiber and a preparation method thereof. Background Art

[0002] At present, magnetoelectricity and electroluminescence are hot topics in fiber research, aiming to develop functional fibers for energy harvesting and luminescence, bringing positive development to smart textiles and wearable devices. The magnetoelectric effect refers to the phenomenon that a material generates an electric field or polarization under the action of a magnetic field. In the existing research, the invention patent application number CN109994315B, "Magnetoelectric composite material composed of magnetic nanofiber ferroelectric film and its preparation method", prepares CoFe2O4 (CFO) magnetic nanofibers by electrospinning method, and coats it with ferroelectric layer Pb(Zr,Ti)O3 film by pulsed laser deposition method, thereby enhancing the magnetoelectric coupling effect. The invention patent application number CN111462943B, "A wireless charging coil enameled wire with an inner layer of magnetic nanoferrite material and its preparation method" mainly includes a magnetic nanoferrite solid core with piezoelectric properties, a conductive middle layer and an insulating outer layer, which can improve the softness and bending performance of the enameled wire, and has high magnetostriction and high magnetoelectric conversion efficiency. Electroluminescence refers to the phenomenon that a material emits light under the action of an electric field. In the existing research, the invention patent application number CN111286975B, "electroluminescent fiber" mainly includes a linear central electrode, a dielectric layer, an electroluminescent layer and a transparent conductive layer. The layer-by-layer coating effect gives the fiber excellent brightness. The invention patent application number CN114990882A, "an electroluminescent fiber and its melt coating preparation method" mainly realizes the loading of the luminescent active layer through melt coating, and obtains a fiber with good luminescent properties and resistance to bending and washing.

[0003] Combining magnetoelectricity and electroluminescence in the same fiber is a complex and innovative research direction. Problems in existing research include material compatibility, ensuring that magnetoelectric materials and electroluminescent materials can coexist in the fiber without interfering with each other, and designing a reasonable fiber structure so that the two functional materials can efficiently play their respective roles in the fiber. Summary of the invention

[0004] The purpose of the present invention is to overcome the deficiencies in the prior art and to provide an electroluminescent magnetic fiber and a preparation method thereof. The electroluminescent magnetic fiber effectively combines magnetoelectricity with electroluminescence, realizes the integration of electroluminescent devices, has good electrical conductivity and magnetic response properties, and can meet practical applications.

[0005] To achieve the above object, the present invention is implemented by adopting the following technical solutions:

[0006] In one aspect, the present invention provides an electroluminescent magnetic fiber, wherein the electroluminescent magnetic fiber is a composite fiber, comprising a core layer, an electroluminescent layer and a conductive layer;

[0007] Wherein, the core layer is silver nanowires AgNWs;

[0008] The electroluminescent layer is a mixture of polyvinylidene fluoride PVDF, neodymium iron boron NdFeB, gallium phosphide GaP and an organic solvent;

[0009] The conductive layer is indium tin oxide ITO.

[0010] Furthermore, in the electroluminescent layer, the concentration of PVDF is 15-20 wt%, the concentration of NdFeB is 10-20 wt%, and the concentration of GaP is 6.5-7.5 wt%.

[0011] In another aspect, the present invention provides a method for preparing the electroluminescent magnetic fiber, comprising:

[0012] PVDF, NdFeB particles and GaP particles are prepared into a sheath spinning solution;

[0013] Spinning the sheath layer spinning solution and the core layer spinning solution into a hollow composite fiber, wherein the core layer spinning solution is deionized water;

[0014] injecting the AgNWs suspension into the hollow structure of the hollow composite fiber to obtain a composite fiber matrix;

[0015] Coating ITO on the outer layer of the composite fiber substrate to obtain a three-layer composite fiber;

[0016] The three-layer structure composite fiber is encapsulated to obtain electroluminescent magnetic fiber.

[0017] Furthermore, the step of preparing the sheath spinning solution from PVDF, NdFeB particles and GaP particles comprises:

[0018] Obtaining raw materials of PVDF, NdFeB particles and GaP particles according to the raw material concentration, and completely dissolving them in an organic solvent to obtain a mixed solution, wherein the diameters of the PVDF and NdFeB particles are 20-50 nm, and the diameter of the GaP particles is 10-30 nm;

[0019] The mixed solution was stirred at 70 °C for 7-8 h at a stirring speed of 600-650 r / min, and then ultrasonically stirred for 1-1.5 h to obtain the sheath spinning solution.

[0020] Furthermore, the organic solvent includes N,N-dimethylformamide (DMF).

[0021] Furthermore, spinning the sheath layer spinning solution and the core layer spinning solution into a hollow composite fiber comprises:

[0022] The propulsion speeds of the microfluidic spinning needles corresponding to the core layer spinning solution and the sheath layer spinning solution are set respectively, so that the microfluidic spinning device starts spinning, and the ejected liquid is replaced by a coagulation bath, and then wound, collected and dried to finally obtain a hollow composite fiber.

[0023] Furthermore, the propulsion speed of the microfluidic spinning needle corresponding to the core layer spinning solution is set to 0.2~0.25 mL / min, and the propulsion speed of the microfluidic spinning needle corresponding to the sheath layer spinning solution is set to 0.4~0.45 mL / min;

[0024] and / or, the coagulation bath comprises deionized water;

[0025] And / or, in the fiber winding and collecting device used for the winding and collecting, the drum diameter is set to 5 cm, the rotation speed is set to 15 r / min, and the drying temperature is set to 70°C.

[0026] Further, the injecting of the AgNWs suspension into the hollow structure of the hollow composite fiber to obtain the composite fiber matrix comprises: injecting the AgNWs suspension into the hollow structure of the hollow composite fiber using a syringe, so that the AgNWs suspension completely fills the hollow structure of the hollow composite fiber;

[0027] Wherein, the needle caliber of the syringe is ≤0.2 mm.

[0028] Furthermore, the concentration of the ITO is 3-4 wt%.

[0029] Furthermore, the three-layer structure composite fiber is encapsulated by surface impregnation, and the encapsulation layer material includes polyurethane PU.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] The electroluminescent magnetic fiber provided by the present invention uses AgNWs as a core layer, PVDF, NdFeB and GaP as an electroluminescent layer, and ITO as a conductive layer. PVDF, NdFeB and GaP are prepared into hollow fibers, magnetic dipole interaction is generated between magnetic nanoparticles NdFeB and AgNWs, AgNWs are injected into the core layer, and ITO is coated on the surface to form an electroluminescent device with the core layer AgNWs as a cathode material, the middle layer GaP as an electroluminescent material, and the sheath layer ITO as an anode material, thereby realizing the integration of electroluminescent devices and effectively combining magnetoelectricity with electroluminescence.

[0032] The electroluminescent magnetic fiber provided by the present invention is obtained through the interaction between layers, and has good electrical conductivity and magnetic response performance, which can meet practical applications. The outermost layer is dip-coated with PU to protect the electroluminescent magnetic fiber and enhance its mechanical strength. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 is a schematic structural diagram of an electroluminescent magnetic fiber provided in an embodiment of the present invention;

[0034] Figure 2 It is a schematic diagram of the mechanism of magnetoelectric effect of the electroluminescent magnetic fiber provided by an embodiment of the present invention;

[0035] Figure 3 It is a schematic diagram of preparing hollow fibers by using microfluidic technology in electroluminescent magnetic fibers provided by an embodiment of the present invention;

[0036] Figure 4 It is a flow chart of the preparation of electroluminescent magnetic fiber provided in an embodiment of the present invention.

[0037] In the figure: 1, sheath spinning solution; 2, core spinning solution; 3, coagulation bath; 4, winding and collecting device; 5, hollow composite fiber; 20, magnetic field; 21, mechanical stress; 22, mobile charge; 100, core layer; 101, electroluminescent layer; 102, conductive layer; 103, protective layer. DETAILED DESCRIPTION

[0038] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0039] The present invention combines magnetic nanoparticles NdFeB with PVDF, and utilizes the coupling effect of the magnetic field generated by NdFeB and the piezoelectric material PVDF to achieve the magnetoelectric effect and form a magnetoelectric composite material. Figure 2 As shown, specifically, the external magnetic field 20 generated by the NdFeB magnet changes to form mechanical stress 21, and the mechanical stress 21 caused by the change in the magnetic field 20 propagates in the PVDF, causing the PVDF to deform. During the deformation process, the PVDF generates charge separation, and the electric polarization forms a voltage output.

[0040] Example 1

[0041] This embodiment provides an electroluminescent magnetic fiber and a preparation method thereof.

[0042] like Figure 1 As shown, the electroluminescent magnetic fiber is a composite fiber, including a core layer 100, an electroluminescent layer 101, a conductive layer 102 and a protective layer 103;

[0043] The core layer 100 is silver nanowires; the electroluminescent layer 101 is a mixture of polyvinylidene fluoride PVDF, neodymium iron boron NdFeB, gallium phosphide GaP and an organic solvent; the conductive layer 102 is indium tin oxide ITO; and the protective layer 103 is polyurethane PU.

[0044] The concentration of PVDF in the electroluminescent layer is 15 wt %, the concentration of NdFeB is 10 wt %, and the concentration of GaP is 6.5 wt %. In this embodiment, the organic solvent in the electroluminescent layer is N,N-dimethylformamide DMF.

[0045] The preparation method of the electroluminescent magnetic fiber provided in this embodiment is as follows Figure 4 As shown, including:

[0046] (1) Preparation of sheath spinning solution: First, 15 wt% PVDF, 10 wt% NdFeB and 6.5 wt% GaP were dissolved in an appropriate amount of DMF solvent, heated and stirred at 70 °C for 7 h at a stirring speed of 600 r / min, and then ultrasonically stirred for 1 h to obtain a uniform spinning solution.

[0047] (2) Microfluidic spinning: First, the core layer spinning solution 2 and the sheath layer spinning solution 1 are added to the microfluidic spinning needle respectively, wherein the core layer spinning solution uses deionized water, and the extrusion speeds of the core layer and the sheath layer parts of the needle connected to the coaxial needle are set to 0.2 mL / min and 0.4 mL / min respectively, and then the fibers formed by the core layer spinning solution and the sheath layer spinning solution are injected into the coagulation bath 3 containing deionized water to obtain the hollow composite fiber 5, and finally the hollow composite fiber 5 is collected on the winding collection device 4. The roller diameter in the winding collection device 4 is set to 5 cm, the rotation speed is set to 15 r / min, and the drying temperature is set to 70 °C. The schematic diagram of the microfluidic spinning process is shown in the figure. Figure 3 shown.

[0048] (3) AgNWs injection: Use a micro syringe with a specification of 0.2 mm to slowly inject the AgNWs suspension into the inner cavity of the hollow composite fiber to ensure that the AgNWs suspension completely fills the inner cavity of the hollow fiber to obtain AgNWs-PVDF / NdFeB / GaP composite fibers.

[0049] (4) Surface coating with ITO: The AgNWs-PVDF / NdFeB / GaP composite fiber was surface coated with 4 wt% ITO and dried in air to obtain a three-layer composite fiber, which mainly includes the core layer cathode material AgNWs, the middle layer electroluminescent material GaP, and the sheath layer anode material ITO.

[0050] (5) Surface impregnation with PU: PU is used as a protective layer for the AgNWs-PVDF / NdFeB / GaP-ITO three-layer composite fiber to give the composite fiber good mechanical strength and obtain electroluminescent magnetic fibers.

[0051] In this embodiment, the core-sheath structure fiber prepared by microfluidic spinning has magnetoelectric properties, and is prepared into electroluminescent magnetic fiber by coating, combining magnetoelectricity and electroluminescence in the same fiber to form an integrated electroluminescent device, wherein the core layer AgNWs is used as the cathode material, the middle layer GaP is used as the electroluminescent material, and the sheath layer ITO is used as the anode material.

[0052] Example 2

[0053] This embodiment provides a method for preparing electroluminescent magnetic fibers, which is different from the first embodiment in that:

[0054] (1) Preparation of sheath spinning solution: First, 15 wt% PVDF, 15 wt% NdFeB and 6.5 wt% GaP were dissolved in an appropriate amount of DMF solvent, heated and stirred at 70 °C for 7 h at a stirring speed of 600 r / min, and then ultrasonically stirred for 1 h to obtain a uniform spinning solution.

[0055] Example 3

[0056] This embodiment provides a method for preparing electroluminescent magnetic fibers, which is different from the first embodiment in that:

[0057] (1) Preparation of sheath spinning solution: First, 15 wt% PVDF, 20 wt% NdFeB and 6.5 wt% GaP were dissolved in an appropriate amount of DMF solvent, heated and stirred at 70 °C for 7 h at a stirring speed of 600 r / min, and then ultrasonically stirred for 1 h to obtain a uniform spinning solution.

[0058] The magnetostrictive strain measurement of the electroluminescent magnetic fibers provided in Examples 1 to 3 of the present invention was respectively performed. The magnetostrictive coefficient of the sample when the longitudinal length was parallel to the external magnetic field was measured by the resistance strain gauge method using a JDAW-2011 magnetostrictive tester. The impedance change of the sample was measured using an impedance analyzer. The coupling effect of the electric field and the magnetic field was further analyzed. The magnetoelectric coupling coefficient was calculated and the results are shown in Table 1.

[0059] Table 1

[0060]

[0061] Through comparative analysis of the electroluminescent magnetic fibers prepared in Examples 1-3, the sample in Example 2 has the best magnetoelectric performance.

[0062] The mechanical properties of the electroluminescent magnetic fibers provided in Examples 1-3 were characterized using an Instron-5967 universal material testing machine. The breaking strength and breaking elongation of the electroluminescent magnetic fibers were tested, respectively. The luminescence degree of the electroluminescent magnetic fibers after successful preparation was observed. The results are shown in Table 2.

[0063] Table 2

[0064]

[0065] It can be seen from Table 2 that the luminescence intensity of the electroluminescent magnetic fibers provided in Examples 1-3 is good, among which the electroluminescent magnetic fibers provided in Example 2 have the highest breaking strength and the smallest breaking elongation, and the mechanical properties are the best.

[0066] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the enlightenment of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the purpose of the present invention and the claims, which all fall within the protection of the present invention.

Claims

1. An electroluminescent magnetic fiber, characterized in that: The electroluminescent magnetic fiber is a composite fiber, comprising a core layer, an electroluminescent layer and a conductive layer; Wherein, the core layer is silver nanowires AgNWs; The electroluminescent layer is a mixture of polyvinylidene fluoride PVDF, neodymium iron boron NdFeB, gallium phosphide GaP and an organic solvent; The conductive layer is indium tin oxide ITO.

2. The electroluminescent magnetic fiber according to claim 1, characterized in that: The concentration of PVDF in the electroluminescent layer is 15-20 wt %, the concentration of NdFeB is 10-20 wt %, and the concentration of GaP is 6.5-7.5 wt %.

3. A method for preparing the electroluminescent magnetic fiber according to claim 1-2, characterized in that: include: PVDF, NdFeB particles and GaP particles are prepared into a sheath spinning solution; Spinning the sheath layer spinning solution and the core layer spinning solution into a hollow composite fiber, wherein the core layer spinning solution is deionized water; injecting the AgNWs suspension into the hollow structure of the hollow composite fiber to obtain a composite fiber matrix; Coating ITO on the outer layer of the composite fiber substrate to obtain a three-layer composite fiber; The three-layer structure composite fiber is encapsulated to obtain electroluminescent magnetic fiber.

4. The method for preparing the electroluminescent magnetic fiber according to claim 3, characterized in that: The method of preparing the sheath spinning solution from PVDF, NdFeB particles and GaP particles comprises: Obtaining raw materials of PVDF, NdFeB particles and GaP particles according to the raw material concentration, and completely dissolving them in an organic solvent to obtain a mixed solution, wherein the diameters of the PVDF and NdFeB particles are 20-50 nm, and the diameter of the GaP particles is 10-30 nm; The mixed solution was stirred at 70 °C for 7-8 h at a stirring speed of 600-650 r / min, and then ultrasonically stirred for 1-1.5 h to obtain the sheath spinning solution.

5. The method for preparing the electroluminescent magnetic fiber according to claim 4, characterized in that: The organic solvent includes N,N-dimethylformamide (DMF).

6. The method for preparing the electroluminescent magnetic fiber according to claim 3, characterized in that: The spinning of the sheath layer spinning solution and the core layer spinning solution into a hollow composite fiber comprises: The propulsion speeds of the microfluidic spinning needles corresponding to the core layer spinning solution and the sheath layer spinning solution are set respectively, so that the microfluidic spinning device starts spinning, and the ejected liquid is replaced by a coagulation bath, and then wound, collected and dried to finally obtain a hollow composite fiber.

7. The method for preparing the electroluminescent magnetic fiber according to claim 6, characterized in that: The propulsion speed of the microfluidic spinning needle corresponding to the core layer spinning solution is set to 0.2-0.25 mL / min, and the propulsion speed of the microfluidic spinning needle corresponding to the sheath layer spinning solution is set to 0.4-0.45 mL / min; and / or, the coagulation bath comprises deionized water; And / or, in the fiber winding and collecting device used for the winding and collecting, the drum diameter is set to 5 cm, the rotation speed is set to 15 r / min, and the drying temperature is set to 70°C.

8. The method for preparing the electroluminescent magnetic fiber according to claim 3, characterized in that: The step of injecting the AgNWs suspension into the hollow structure of the hollow composite fiber to obtain the composite fiber matrix comprises: injecting the AgNWs suspension into the hollow structure of the hollow composite fiber using a syringe, so that the AgNWs suspension completely fills the hollow structure of the hollow composite fiber; Wherein, the needle caliber of the syringe is ≤0.2 mm.

9. The method for preparing the electroluminescent magnetic fiber according to claim 3, characterized in that: The concentration of the ITO is 3-4 wt %.

10. The method for preparing the electroluminescent magnetic fiber according to claim 3, characterized in that: The three-layer structure composite fiber is encapsulated by surface impregnation, and the encapsulation layer material includes polyurethane PU.

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