CN116949623B

CN116949623B - A core-shell structured conductive fiber, its preparation method, and its application in thermal management fabrics.

Info

Publication number: CN116949623B
Application number: CN202310711412.5A
Authority: CN
Inventors: 冷劲松; 刘稳; 孔德艳; 刘彦菊
Original assignee: Harbin Institute of Technology Shenzhen
Current assignee: Harbin Institute of Technology Shenzhen
Priority date: 2023-06-15
Filing date: 2023-06-15
Publication date: 2025-11-25
Anticipated expiration: 2043-06-15
Also published as: CN116949623A

Abstract

This invention discloses a core-shell structured conductive fiber, its preparation method, and its application in thermal management fabrics. The conductive fiber uses a flexible polymer fiber as the shell and a carbon fiber as the core. A high-toughness polymer fiber membrane matrix is prepared using multi-level hydrogen bonding cross-linking, allowing its mechanical properties to match those of high-strength, high-modulus carbon fibers. The core-shell structured conductive fiber is obtained by wrapping and twisting the carbon fibers. The prepared conductive fiber is externally insulated and has an internal electrothermal effect, capable of generating heat at a voltage of 2V, reaching temperatures up to 40℃ (a suitable temperature for human physiotherapy). It can be woven into wearable flexible fabrics for thermal therapy and warmth, offering low cost, a simple preparation process, and breakthroughs in traditional filler preparation methods, resulting in greater stability and enabling large-scale production.

Description

Core-shell structure conductive fiber, preparation method thereof and application thereof in thermal management fabric

Technical Field

The invention belongs to the technical field of shape memory polymer fibers and thermal management fiber fabrics, and particularly relates to a core-shell structure conductive fiber, a preparation method thereof and application thereof in thermal management fabrics.

Background

Conventional fibers do not have a conductive function, and thus require an additional filler to impart conductive properties thereto. The existing conductive fibers mainly comprise carbon material conductive fibers, metal conductive fibers and metal composite conductive fibers. The carbon material conductive fiber is prepared by dispersing conductive carbon nano tubes, carbon black, graphite and other particles in a polymer matrix through a physical method, but the fiber prepared through the method is generally unstable in conductive performance and cannot be bent or stretched greatly, and in addition, the metal conductive fiber is stable in conductive performance, but the comfort and the functionality of the prepared clothing are reduced due to the fact that the hardness of metal is too large and the metal does not have a Joule heating effect, so that the market popularization and use progress of the conductive fiber fabric is seriously influenced.

The shape memory polymer fiber is an important branch of the shape memory polymer, and has great application potential and practical value in various fields because of the characteristics of micro-nano structure, large specific surface area, high porosity, three-dimensional structure and the like. Such as drug delivery systems for biomedical applications, wound dressings, and artificial muscles and hand-turns in the field of soft robotics, smart textile garments achieve the goals of thermal wet comfort and pressure comfort. With the advent of the intelligent age, the development of the flexible electronic device has been spanned, and the combination of artificial intelligence, microelectronic technology and new textile materials has promoted the development of functionality and science and technology of textile clothing.

Therefore, how to combine functional polymer fiber and conductive material well, prepare the textile that has the function of generating heat, large deformation electric heat is stable, not only can play cold-proof effect, can also be used for heat recuperation to the patient that has body cold, rheumatism, has antistatic, antibiotic and electromagnetic shielding function simultaneously, and the electricity is driven to generate heat simultaneously, does not cause pollution to the environment, still is a urgent need to solve problem.

Disclosure of Invention

In order to solve the technical problems, the invention provides a preparation method of a core-shell structure conductive fiber and application of the core-shell structure conductive fiber in thermal management fabrics.

In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:

the conductive fiber with the core-shell structure is prepared by taking a polymer fiber membrane prepared from a polymer elastomer through electrostatic spinning as a shell, taking the conductive fiber as a core body, wrapping the core body in the shell and twisting.

Preferably, the polymer elastomer is a polyurea elastomer and the conductive fibers are carbon fibers.

The invention also provides a preparation method of the core-shell structure conductive fiber, which is characterized by comprising the following steps:

(1) Preparing a polymer fiber membrane:

Dropwise adding a diamine monomer solution into a diisocyanate monomer solution, stirring the mixture under ice bath, reacting the mixture at room temperature for 2 to 4 hours, dropwise adding an m-phthalyl hydrazine monomer solution, continuously stirring the mixture for 45 to 55 hours, pouring the transparent viscous reaction solution into a mould, drying the reaction solution to prepare a polymer elastomer;

(2) Preparing core-shell structure conductive fibers:

Cutting the polymer fiber membrane into rectangular strips, wrapping the conductive fibers in the polymer fiber membrane, twisting by using a twisting machine, and finally twisting the two ends in parallel for lock twisting to obtain the conductive fibers with the core-shell structure.

Preferably, in the step (1), the concentration of the electrostatic spinning solution is 80-90mg/ml during electrostatic spinning.

Preferably, in the step (1), the diisocyanate monomer is selected from one of toluene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate and dicyclohexyl diisocyanate, and the diamine is selected from at least one of polyetheramine 2000, polyetheramine 400 and 1, 3-diamino-2-propanol.

Preferably, in the step (1), the molar ratio of the diisocyanate monomer to the diamine monomer to the isophthalhydrazide monomer is 10 (7-8): 2-3.

Preferably, in step (1), the concentration of the diisocyanate monomer, diamine monomer, and isophthalhydrazide monomer is 10 to 50wt%.

Preferably, in step (2), the mass ratio of the polymer fiber film to the conductive fiber is (0.5-1): 1.

The invention also provides application of the core-shell structure conductive fiber prepared by the preparation method in a thermal management fabric, which is characterized by comprising the following steps:

and respectively taking the core-shell structure conductive fibers and cotton threads as weft threads and warp threads of the woven fabric, weaving the woven fabric, and electrifying to obtain heat.

Preferably, the fabric temperature reaches 37-40 ℃ when the energizing voltage is 2V. The molecular structure relates to multi-stage hydrogen bond crosslinking, so that the toughness of the material is improved.

To reach different purposes, such as the field of wearable clothes for heating, health preserving and the like.

Compared with the prior art, the invention has the following beneficial effects:

1. The prepared polymer fiber has toughness of up to 256MJ/m ³ through multistage hydrogen bonding, so that the polymer fiber has better compatibility with carbon fiber and metal fiber with higher rigidity;

2. firstly, the carbon fiber and the polymer fiber are twisted and integrated to prepare the conductive fiber with better flexibility, and the preparation method is simple and low in cost;

3. The conductive fiber can be prepared into a braided fabric through braiding, the temperature (33-40 ℃) suitable for a human body can be generated by using lower voltage (1-2V), the effects of warming, cold dispelling and physiotherapy are achieved, and when the voltage is 3-5V, the conductive fiber can be used as heating equipment, and the highest temperature can reach 50-120 ℃.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and together with the description, serve to explain the principles of the invention, wherein:

FIG. 1 is a diagram of a polymer fiber membrane prepared by electrospinning in example 1;

FIG. 2 is a scanning electron microscope image of the polymer fiber of example 1;

FIG. 3 is a schematic diagram of the preparation of the conductive fiber with the core-shell structure in example 1;

fig. 4 is a fabric diagram of the conductive fiber of the core-shell structure of example 1.

FIG. 5 is a graph of mechanical properties of the polyurea elastomer of example 1.

Detailed Description

The following disclosure provides many different embodiments, or examples, for implementing different features of the invention. In order to simplify the present disclosure, components and arrangements of specific examples are described below. They are, of course, merely examples and are not intended to limit the invention. Furthermore, the present invention may repeat reference numerals and/or letters in the various examples, which are for the purpose of brevity and clarity, and which do not themselves indicate the relationship between the various embodiments and/or arrangements discussed.

In order to solve the technical problems, the invention provides a core-shell structure conductive fiber, a thermal management fabric and a preparation method thereof, natural or artificial fibers and the conductive fiber can be simply combined by the method to prepare the conductive flexible fiber which has stable conductive performance and is feasible and can be produced in a large scale, and the wearable textile clothing can be prepared by braiding.

(1) Preparation of polymer fibers

The polymer fiber is polyurea fiber with excellent mechanical properties, which is prepared by introducing multi-stage hydrogen bonds into a molecular structure and gradually polymerizing diisocyanate monomers, diamine monomers and dihydrazide monomers by utilizing the multi-stage hydrogen bond acting force among molecules.

(2) Preparation of conductive fibers

The prepared conductive fiber is of a core-shell structure, the shell material is the polyurea fiber membrane prepared by the method, and the core material is a conductive carbon fiber material. The preparation process of the conductive fiber comprises the steps of cutting a fiber membrane obtained by the electrostatic spinning, wrapping carbon fibers in the fiber membrane according to a certain mass ratio, and carrying out twisting-lock twisting forming by using a rotating speed machine and loading 2g to prepare the hemp-shaped conductive fiber.

(3) Testing of heating function

First, the highest temperature that can be generated by using Joule heat was studied for conductive fibers having a length of 10cm and a diameter of 0.5mm at different voltages.

Preferably, the highest temperature is 38-40 ℃ which is acceptable for human body and can achieve the effect of thermal physiotherapy.

Preferably, the conductive fiber has better thermal stability, and continuously circulates for 20 times, and the maximum temperature amplitude changes by not more than 1 ℃.

Preferably, the conductive fiber has better stability of resistance value, and the resistance change is smaller in the bending and straightening processes, so that the function of thermal physiotherapy is not affected.

(4) Preparation of wearable intelligent fabric

Preferably, the wearable intelligent textile is composed of a plurality of conductive fibers and knitting yarns with different colors.

The conductive fibers are warp yarns, two ends of the conductive fibers are fixed, the woolen yarns are weft yarns, the conductive fibers are woven by using a small tapestry loom of 10cm x10 cm, multicolor collocation can be carried out according to the colors of different woolen yarns, and a woven fabric with a thermal physiotherapy function is woven, so that the conductive fiber fabric has the functions of thermal insulation and physiotherapy.

Example 1

1. Preparation of a polymer fiber film:

The polymer elastomer is polyurea elastomer, and the polyurea polymer is prepared by gradual polymerization, and the preparation steps involved are as follows:

(1) Diamine monomer (50 wt% polyether amine 2000 solution, 10wt% 1, 3-diamino-2-propanol solution) solution is dropwise added into 50wt% isophorone diisocyanate monomer solution (N, N-dimethyl acetamide solvent) dropwise, the mixture is continuously stirred for 20min in ice bath, the mixture is placed at room temperature for continuous reaction for 3h, 20wt% m-phthalhydrazide solution is dropwise added, the mixture is continuously stirred at room temperature for 48h, and transparent viscous reaction liquid is obtained after the reaction is finished. Pouring into a mould, and drying in a drying oven to obtain the polyurea polymer elastomer.

Wherein the molar ratio of isophorone diisocyanate to polyetheramine 2000:1, 3-diamino-2-propanol to isophthalhydrazide monomer is 10:4:4:2.

(2) The polyurea elastomer prepared by the method is dissolved in methanol solution, and is stirred uniformly until uniform transparent viscous liquid is formed, and the electrostatic spinning solution with the mass concentration of 80-90mg/ml is prepared.

(3) Pouring the prepared polyurea spinning solution into a 20mL syringe, mounting the syringe on a propelling device, connecting the device, adhering a receiving cloth on a roller, starting an electrostatic spinning power supply, starting spinning, wherein the power supply voltage is 15kV, the rotating speed is 500r/min, the propelling speed is 0.5mL/h, and collecting a polyurea fiber membrane, as shown in figure 1, wherein the microscopic view of the polyurea elastomer is shown in figure 2, and the diameter of a single silk thread is 3-4 mu m. As shown in FIG. 5, the toughness of the polyurea elastomer is 256MJ/m ³, the toughness is 1.5 times of that of spider silk, the polyurea elastomer has mechanical strength of 30MPa and 700% ductility, and the polyurea elastomer has both strength and toughness, so that theoretical support is provided for preparing a tough polyurea fiber film shell to match with a high-strength carbon fiber inner core.

2. Preparing core-shell structure conductive fibers:

the polyurea fiber film prepared by the electrostatic spinning was cut into a long strip shape with a width of 1cm, a length of 25cm and a thickness of 0.15 mm.

Wrapping carbon fibers with the length of 30cm and the diameter of 0.5mm in a polyurea fiber film, twisting the polyurea fiber film and the carbon fibers with the mass ratio of 1:0.5 by using a twisting machine, wherein the twisting speed is 1000r/min, twisting for 30s, and finally twisting the two ends of the twisted yarn. The schematic diagram of the preparation process of the core-shell structure conductive fiber is shown in fig. 3.

3. Conducting performance test:

The resistance of the conductive fiber is tested by using a digital multimeter, the resistance value is tested, and after the digital multimeter is subjected to a 360-degree folding test for 1000 times, the resistance change range is 37-39Ω, and the change value does not influence the resistance value as the wearable clothes for heat management.

4. And (3) testing heat management performance:

The thermal management performance means that heat generated by joule heat causes an increase in the temperature of the fiber, and thus can be applied to thermal management fabrics such as thermal treatment, heating, and the like of fabrics by utilizing the effect.

The thermal management performance is recorded by researching the temperature and the temperature rising speed of the surface of the conductive fiber under different voltages, so that the optimal voltage is selected.

The conductive fiber prepared in this example 1 reached a maximum temperature of 33 ℃ after 40 seconds at a voltage of 1V.

5. Preparation of wearable intelligent fabric:

the wearable intelligent fabric is composed of 12 conductive fibers and knitting yarns with different colors.

The core-shell structure conductive fiber prepared by the embodiment is used as warp, two ends are fixed, the woolen yarns are used as weft, the knitting is performed by using a small tapestry loom of 10cm x 10cm, multicolor collocation can be performed according to the colors of different woolen yarns, a knitting fabric with a thermal physiotherapy function is knitted, the thermal physiotherapy function is achieved, and a fabric diagram is shown in fig. 4.

Example 2

The embodiment differs from embodiment 1 only in that the voltage is 2V, and at this voltage, the surface temperature of the core-shell structure conductive fiber prepared in this embodiment may reach the highest temperature of 40 ℃ after 40 s. This temperature, slightly above the human body temperature, can be used as a driving voltage for thermal management.

Example 3

The difference between this example and example 1 is that the voltage is 3V, and the surface temperature of the core-shell structure conductive fiber prepared in this example can reach 54 ℃ and the highest temperature can reach 60 ℃ after 40s.

Example 4

The difference between this example and example 1 is that the voltage is 4V, and the surface temperature of the core-shell structure conductive fiber prepared in this example reaches 82 ℃ and the highest temperature reaches 87 ℃ after 40 s.

Example 5

The difference between this example and example 1 is that the voltage is 5V, and the surface temperature of the core-shell structure conductive fiber prepared in this example reaches 115 ℃ and the highest temperature reaches 120 ℃ after 40s.

Application example 1

The fabric prepared in the embodiment 1 is connected with leads at different positions, then is powered on, and can observe the temperature generated on the surface of the fabric under the action of Joule heat with the aid of a thermal imager, so as to achieve the effects of heating, thermal therapy and the like.

Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention herein. This invention is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.

It is to be understood that the invention is not limited to the precise arrangements and instrumentalities shown in the drawings, which have been described above, and that various modifications and changes may be effected without departing from the scope thereof. The scope of the invention is limited only by the appended claims.

Claims

1. A method for preparing a core-shell structured conductive fiber, characterized by comprising the following steps:

(1) Preparation of polymer fiber membrane:

A diamine monomer solution was added dropwise to a diisocyanate monomer solution, and the mixture was stirred in an ice bath. After reacting at room temperature for 2–4 hours, an isophthalic hydrazide monomer solution was added dropwise, and the mixture was stirred for another 45–55 hours. The transparent, viscous reaction solution was poured into a mold and dried to prepare a polymer elastomer. The polymer elastomer was dissolved in a methanol solution and stirred until a uniform, transparent electrospinning solution was formed. The electrospinning solution was poured into a syringe and installed on a propulsion device. The receiving cloth was attached to a roller, and the polymer fiber membrane was electrospun and collected.

(2) Preparation of core-shell structured conductive fibers:

The polymer fiber membrane is cut into rectangular strips, and conductive fibers are wrapped inside the polymer fiber membrane. The strips are then twisted using a twisting machine, and finally the two ends are twisted together for locking, thus producing the core-shell structure conductive fiber.

2. The method for preparing core-shell structured conductive fibers according to claim 1, characterized in that, in step (1), the concentration of the electrospinning solution during electrospinning is 80-90 mg/ml.

3. The method for preparing core-shell structured conductive fibers according to claim 1, characterized in that, in step (1), the diisocyanate is selected from at least one of toluene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, and dicyclohexyl diisocyanate; and the diamine is selected from at least one of polyetheramine 2000, polyetheramine 400, and 1,3-diamino-2-propanol.

4. The method for preparing core-shell structured conductive fibers according to claim 1, characterized in that, in step (1), the molar ratio of the diisocyanate monomer: the diamine monomer: the isophthalic acid hydrazine monomer is 10:(7-8):(2-3).

5. The method for preparing core-shell structured conductive fibers according to claim 1, characterized in that, in step (1), the concentrations of the diisocyanate monomer, the diamine monomer, and the isophthalic acid hydrazine monomer are all 10-50 wt%.

6. The method for preparing core-shell structured conductive fibers according to claim 1, characterized in that, in step (2), the mass ratio of the polymer fiber membrane to the conductive fiber is (0.5-1):1.

7. The core-shell structured conductive fiber prepared by the preparation method according to any one of claims 1-6, characterized in that the core-shell structured conductive fiber uses a polymer fiber membrane made by electrospinning a polymer elastomer as the shell and a conductive fiber as the core, and the core is wrapped in the shell and twisted to form the core-shell structured conductive fiber.

8. The core-shell structured conductive fiber according to claim 7, wherein the polymer elastomer is a polyurea elastomer and the conductive fiber is a carbon fiber.

9. The application of the core-shell structured conductive fiber prepared by the preparation method according to any one of claims 1-6 in thermal management fabrics, characterized in that it comprises the following steps:

The core-shell structure conductive fibers and cotton threads are used as the weft and warp threads of the woven fabric, respectively, and then woven into a fabric to generate heat when electricity is applied.

10. The application according to claim 9, wherein when the energizing voltage is 2V, the temperature of the fabric reaches 37-40℃.