Smart fibers, usually fibers that are sensitive to environmental changes or stimuli and capable of reacting, are important building blocks in smart wearable fabrics. Smart fibers can be integrated into armbands, sleeves, garments, helmets in the form of smart fabrics. Among the belts and other parts, and as the core unit of functional components such as wearable sensors, brakes, energy devices, temperature control fabrics and heaters, they are used in flexible wearable intelligent systems. However, most fabric fibers are now made of natural polymers. Or synthetic polymers. These polymers have intrinsic thermal insulation and electrical insulation properties, making it difficult to integrate organically with miniaturized circuits, thus limiting not only the application of fabric fibers in conventional electronic devices, but also the new types of The development of wearable electronic devices and intelligent robots. In addition, how to realize the functional integration of intelligent fibers in the face of complex environment and human-computer interaction with multiple stimuli is still a major challenge, and it is also important for the development of new multifunctional intelligent wearable systems in the future. opportunity.
Based on the functional integration of intelligent fiber multi-stimulus response, the aerogel team of the Suzhou Institute of Nanotechnology and Nano-Bionics of the Chinese Academy of Sciences ingeniously combines graphene aerogel fibers, phase change materials and superhydrophobic coatings to obtain a flexibility. Self-cleaning graphene aerogel intelligent phase change fiber, which realizes energy conversion and storage of composite fiber, self-cleaning, intelligent temperature regulation, heating and other multiple stimuli response functions. The specific preparation process is as follows: Firstly, wet spinning In the silk process, the graphene oxide liquid crystal is spun into a specific coagulation bath, and a regular, continuous, porous graphene aerogel fiber is prepared by chemical reduction-supercritical drying; then the organic phase is changed by impregnation filling. Materials (such as paraffin, polyethylene glycol, higher fatty acids, etc.) are introduced into the porous network structure of aerogel fibers to obtain graphene aerogel phase change composite fibers; finally, a fluorocarbon hydrophobic coating is coated on the composite fibers to obtain Flexible graphene aerogel smart fiber with self-cleaning function and multiple stimulating response behavior.
Studies have shown that this new type of smart fiber has an adjustable phase transition enthalpy (0-186 J/g), excellent mechanical/electrical properties, self-cleaning and multiple stimuli response (light, electricity, temperature) thermal energy conversion and Storage/release function, and fiber can be twisted and woven. Analyze and explore the stimuli response behavior in complex environments for individual fibers, fiber bundles and fabrics: Electro-thermal response of fibers when the fibers are bent or knotted The behavior is not affected. When the fibers are bundled into bundles, heat exchange between the fibers can reduce the heat loss of the fibers to the environment, thereby exhibiting a faster electric heating response and a higher response temperature; the fiber fabric is at room temperature and The photo-thermal response behavior is observed in low temperature environments, and as the density of the fiber fabric increases, the photothermal response has a faster, higher temperature response. Further, the thermocouple and data logger are used to analyze the single Root fiber, electric heating of fiber fabric, photothermal response history, and detailed study of fiber types (fiber blended fabrics of different phase change materials), fiber fabric density, external environment (temperature, humidity and stress) The effect of thermal energy capture and release is achieved by the thermal energy storage, release and temperature regulation functions of the multi-temperature zone of the smart fabric (as shown).
The graphene aerogel smart fiber obtained by ingeniously combining graphene aerogel fiber, phase change material and fluorocarbon resin realizes multi-functional integration under multiple stimuli response, and can be reproduced in fiber-twisted yarn and Among the woven fabrics, it has broad application prospects in the field of new generations of smart wearable fabrics and portable electronic devices. Related research results are based on Multiresponsive Graphene-Aerogel–Directed Phase-Change Smart Fibers, which has been published online in the international journal “Advanced”. Materials (Advanced Materials, 2018, 30, DOI: 10.1002/adma.201801754).
Ph.D. student Li Guangyong (Beijing Institute of Technology and Suzhou Nano Institute) is the first author of the paper. Zhang Xuetong, a researcher at Suzhou Nano Institute, is the author of the paper. The collaborators include Hong Guo, a professor at the University of Macau, and Song Wenhui, a professor at University College London. The National Key Research and Development Program (2016YFA0203301), the National Natural Science Foundation of China (51572285), the British Newton Senior Scholars Fund (NA170184) and the Natural Science Foundation of Jiangsu Province (BK20170428) were jointly funded.
Figure: Schematic diagram of the multiple stimuli response of graphene aerogel smart fibers (a), optical photographs of the woven pattern (b, c,) and infrared photos of the photo-thermal response (b1, c1), its smart fabric (d Internal illustration) Thermal energy conversion and storage/release history under light/electric stimulus response (d).
