CN-120519979-B - Coaxial aerogel liquid crystal elastomer fiber with sheath-core structure, and preparation method and application thereof

CN120519979BCN 120519979 BCN120519979 BCN 120519979BCN-120519979-B

Abstract

The invention relates to the technical field of functional materials, in particular to a coaxial aerogel liquid crystal elastomer fiber with a skin-core structure, and a preparation method and application thereof. The coaxial aerogel liquid crystal elastomer fiber with the sheath-core structure comprises a core layer and a compact skin layer wrapping the core layer, wherein the core layer is of a porous structure, the compact skin layer is made of a skin layer spinning solution comprising a first liquid crystal monomer, a first chain extender and a first cross-linking agent, the core layer is made of a core layer spinning solution comprising a second liquid crystal monomer, a second chain extender and a second cross-linking agent, and the concentration of the first liquid crystal monomer in the skin layer spinning solution is greater than that of the second liquid crystal monomer in the core layer spinning solution. According to the invention, the liquid crystal elastomer is effectively combined with the aerogel, and the prepared coaxial aerogel liquid crystal elastomer fiber with the skin-core structure has the characteristics of high toughness, high tensile strength, excellent heat insulation performance, actuation performance and self-adaptive heat management function, and has potential application value in the fields of intelligent actuation and self-adaptive heat management.

Inventors

ZHANG XINHAI
GAO HAOQIANG
CHENG YANHUA
ZHU MEIFANG

Assignees

东华大学

Dates

Publication Date: 20260508
Application Date: 20250526

Claims (7)

1. A coaxial aerogel liquid crystal elastomer fiber with a sheath-core structure, which is characterized by comprising a core layer and a compact skin layer wrapping the core layer, wherein the core layer has a porous structure; The compact cortex is made of a cortex spinning solution comprising a first liquid crystal monomer, a first chain extender and a first cross-linking agent; the core layer is prepared from a core layer spinning solution comprising a second liquid crystal monomer, a second chain extender and a second cross-linking agent, wherein the core layer spinning solution and the core layer spinning solution are subjected to drying treatment after a skin-core structure is prepared in a mode of ultraviolet irradiation induced reactive coaxial spinning, so that the coaxial aerogel liquid crystal elastomer fiber with the skin-core structure is prepared; The concentration of the first liquid crystal monomer in the cortex spinning solution is greater than the concentration of the second liquid crystal monomer in the core layer spinning solution, wherein the concentration of the first liquid crystal monomer in the cortex spinning solution is 300-1000 mg/mL, and the concentration of the second liquid crystal monomer in the core layer spinning solution is 100-250 mg/mL; In the core layer spinning solution, the mole ratio of the second liquid crystal monomer to the second chain extender to the second cross-linking agent is (3-4): 1-2): 1; the first liquid crystal monomer or the second liquid crystal monomer comprises at least one of 1, 4-bis- [4- (3-acryloxypropoxy) benzoyloxy ] -2-methylbenzene, 1, 4-bis- [4- (6-acryloxyhexyloxy) benzoyloxy ] -2-methylbenzene, 4-cyanophenyl 4- ((6- (acryloxyhexyl) oxy) benzoate, 4' -propenyl biphenyl cyanide, polysiloxane side chain propenyl liquid crystal and azobenzene acrylate liquid crystal; The first chain extender or the second chain extender comprises at least one of hexanedithiol, octanedithiol, 2'- (1, 2-ethanediylbisoxo) bis-ethanethiol, 1, 3-propanedithiol, 1, 2-propanedithiol, 1, 11-undecanedithiol, 4' -dimercaptodiphenyl ether, pentaerythritol tetrakis (3-mercaptopropionate), 2, 3-dimercaptopropanol, 1, 4-benzenedithiol; The cross-linking agent comprises at least one of pentaerythritol tetra (3-mercaptopropionic acid), tetra-mercaptobenzene, tetra-mercaptoporphyrin and tetra-mercaptopolyethylene glycol.
2. A method of making the coaxial aerogel liquid crystal elastomer fiber having a sheath-core structure of claim 1, comprising the steps of: Adding a first liquid crystal monomer, a first chain extender, a first cross-linking agent, a first catalyst and a first photoinitiator into a first organic solvent for first stirring treatment to obtain a cortex spinning solution; adding a second liquid crystal monomer, a second chain extender, a second crosslinking agent and a second catalyst into a second organic solvent for ultrasonic treatment, and then adding an inhibitor and a second photoinitiator for second stirring treatment to obtain a core spinning solution; Coaxially spinning the cortex spinning solution and the core spinning solution under ultraviolet irradiation to obtain coaxial liquid crystal gel fibers; And drying the coaxial liquid crystal gel fiber to obtain the coaxial aerogel liquid crystal elastomer fiber with the skin-core structure.
3. The method for preparing the coaxial aerogel liquid crystal elastomer fiber with the sheath-core structure according to claim 2, wherein the content of the first catalyst in the sheath spinning solution is 0.5-5 wt%, and the content of the first photoinitiator is 1-3 wt%; And/or, in the core spinning solution, the content of the second catalyst is 0.5-5 wt%, the content of the inhibitor is 1-3 wt%, and the content of the second photoinitiator is 1-3 wt%.
4. The method for preparing the coaxial aerogel liquid crystal elastomer fiber with the sheath-core structure according to claim 2, wherein the first catalyst or the second catalyst comprises triethylamine or n-propylenediamine, the first photoinitiator or the second photoinitiator comprises benzildimethyl ether or phenyl bis (2, 4, 6-trimethylbenzoyl) phosphine oxide, the inhibitor comprises 2, 6-di-tert-butyl-p-cresol, and the first organic solvent or the second organic solvent comprises acetone, toluene or xylene.
5. The method for preparing the coaxial aerogel liquid crystal elastomer fiber with the sheath-core structure according to claim 2, wherein in the first stirring treatment, the temperature is 20-30 ℃ and the speed is 100-500 rpm; and/or in the second stirring treatment, the temperature is 20-30 ℃ and the speed is 100-500 rpm; And/or the drying treatment is supercritical drying treatment or freeze drying treatment; The temperature is 35-50 ℃, the pressure is 1000-1300 Pa, and the time is 6-24 hours in the supercritical drying treatment, and the temperature is-50-90 ℃ and the time is 24-72 hours in the freeze drying treatment.
6. Use of the coaxial aerogel liquid crystal elastomer fiber with a sheath-core structure according to claim 1 or the coaxial aerogel liquid crystal elastomer fiber with a sheath-core structure prepared by the preparation method of the coaxial aerogel liquid crystal elastomer fiber with a sheath-core structure according to any one of claims 2 to 5 for preparing an actuator.
7. A fabric comprising the coaxial aerogel liquid crystal elastomer fiber having a sheath-core structure of claim 1 or the coaxial aerogel liquid crystal elastomer fiber having a sheath-core structure produced by the production method of the coaxial aerogel liquid crystal elastomer fiber having a sheath-core structure of any one of claims 2 to 5.

Description

Coaxial aerogel liquid crystal elastomer fiber with sheath-core structure, and preparation method and application thereof Technical Field The invention relates to the technical field of functional materials, in particular to a coaxial aerogel liquid crystal elastomer fiber with a skin-core structure, and a preparation method and application thereof. Background Aerogels are recognized as one of the most desirable insulating materials due to their high porosity, large specific surface area, and low thermal conductivity. In recent years, aerogel fibers have received increasing attention in the fields of smart fabrics, flexible electronic devices, and the like by combining the thermal insulation properties of aerogels with the flexibility of the fibers. However, most aerogel fibers are single-function, rely on static insulation, and limit the application scenarios. For example, chinese patent publication No. CN116555930a discloses a composite aerogel fiber for adaptive thermal management and dynamic display, and the prepared composite aerogel fiber has good heat insulation performance and temperature response color change function by compounding thermochromic material into cellulose aerogel fiber, but the composite aerogel fiber lacks active actuation capability (no actuation performance). With the rapid development of flexible electronics, soft robots, and wearable devices, there is an increasing demand for smart materials that have both thermal insulation and active actuation capabilities (e.g., actuation capabilities). As an emerging intelligent high polymer material, the Liquid Crystal Elastomer (LCE) can realize bidirectional driving response (with actuation performance) under external stimulus due to the orientation order of liquid crystal elements in a molecular structure, and has wide application prospects in the fields of artificial intelligence, photoelectric materials, bioengineering, soft robots and the like. However, conventional liquid crystal elastomers generally suffer from poor thermal insulation, insufficient toughness, low actuation stress, and the like, which greatly limits their application. At present, how to organically combine the heat insulation performance of aerogel with the actuation performance of liquid crystal elastomer is still a technical problem to be solved. In addition, fiber materials capable of simultaneously realizing high toughness, high-efficiency heat insulation performance, actuation performance and self-adaptive heat management function are rarely reported in the prior art. This lack of materials makes the development of next generation smart devices that are adaptive to extreme environments, with active tuning capabilities, a significant challenge. Therefore, the novel fiber material with high toughness, high-efficiency heat insulation performance, actuation performance and self-adaptive heat management function is developed, not only has important scientific significance, but also provides an innovative material solution for the leading-edge fields of flexible electronics, self-adaptive heat management systems, soft robots and the like. Disclosure of Invention The coaxial aerogel liquid crystal elastomer fiber with the sheath-core structure has the advantages of high toughness, high tensile strength, excellent heat insulation performance, actuation performance and self-adaptive heat management function, and good braiding property. The invention also provides a preparation method of the coaxial aerogel liquid crystal elastomer fiber with the sheath-core structure, and the coaxial aerogel liquid crystal elastomer fiber with the sheath-core structure with high toughness, high tensile strength, excellent heat insulation performance, actuation performance, self-adaptive heat management function and good braiding property can be prepared by the method. The invention also provides the coaxial aerogel liquid crystal elastomer fiber with the sheath-core structure or the application of the coaxial aerogel liquid crystal elastomer fiber with the sheath-core structure prepared by the preparation method of the coaxial aerogel liquid crystal elastomer fiber with the sheath-core structure in the preparation of an actuator. The coaxial aerogel liquid crystal elastomer fiber with the sheath-core structure has actuating performance, so that the coaxial aerogel liquid crystal elastomer fiber can be applied to an actuator. The invention also provides a fabric, which comprises the coaxial aerogel liquid crystal elastomer fiber with the sheath-core structure or the coaxial aerogel liquid crystal elastomer fiber with the sheath-core structure prepared by the preparation method of the coaxial aerogel liquid crystal elastomer fiber with the sheath-core structure. The inventor researches show that the coaxial aerogel liquid crystal elastomer fiber with the skin-core structure has good braiding property, and the fabric obtained by braiding the coaxial aerogel liquid crystal elastomer fiber wi