In Situ Loading of Polypyrrole onto Aramid Nanofiber and Carbon Nanotube Aerogel Fibers as Physiology and Motion Sensors

Abstract

Nanocomposite conductive fiber has been newly developed as a lightweight material with high flexibility and strong weavability, which can meet the requirements of flexible wearable devices. Herein, lightweight porous aramid nanofibers (ANF) and carbon nanotube (CNT) aerogel fibers coated with polypyrrole (PPy) layers are prepared by a wet spinning method for motion detection and information transmission. The ANF/CNT/PPy aerogel fiber with low density (56.3 mg/cm3), conductivity (6.43 S/m), and tensile strength (2.88 MPa) were used as motion sensors with high sensitivity (0.12) and long life (1000 cycles). At the same time, the differential conductivity of aerogel fibers is utilized to reduce the information transmission time (up to 46%). High- and low-temperature-resistant (−196 to 100 °C) aerogel fibers are also available as a quick heater and ionic solution detector. In summary, the prepared ANF/CNT/PPy aerogel fiber can be used as a multifunctional sensor for human-health detection and motion monitoring.

‘Rigid‐soft’ synergistic effects to improve the microstructure and superflexibility properties of aramid nanofiber aerogel

“…The pore structure and morphology of aerogel are related to the freezing method and composition of aerogel. Through the directional freezing and the CNF/PVA synergistic, the composite gel is frozen and layered crystals occur 19 . When the ice crystals sublimate form layered pores and polygonal secondary pores.…”

“…Through the directional freezing and the CNF/PVA synergistic, the composite gel is frozen and layered crystals occur. 19 When the ice crystals sublimate form layered pores and polygonal secondary pores. Therefore, composition and freezing mode directly determine the shape of secondary pores in ANF-based nanofiber aerogel.…”

Stretchable One-Dimensional Conductors for Wearable Applications

“…Compared with bulk aerogels, aerogel-based fibers demonstrate high flexibility and weavability. Currently, aerogel fibers have been successfully fabricated from various materials, such as Kevlar, silica, graphenes, , carbon nanotubes, Mxene, conductive polymers, etc. Different from bulky aerogels based on a static sol–gel transition (SST) method, the preparation of aerogel fibers must ensure a continuous and stable gel fiber by a fast dynamic sol–gel transition (DST) method that obeys the following two rules: (i) the spinning dope should have a good spinnability, and (ii) the gelation process must be fast to maintain the shape of the fiber…”

Enhanced Electromagnetic Shielding and Thermal Management Properties in MXene/Aramid Nanofiber Films Fabricated by Intermittent Filtration

“…In general, polymer composites with conductive fillers (such as graphene, − carbon nanotubes, − metal nanoparticles and nanowires , ) have been widely explored in terms of flexible EMI shielding and thermal management films owing to their favorable lightweight, anticorrosion, and machinability. − Nevertheless, most fillers are short of functional groups, which are difficult to disperse uniformly in the matrix. On the other hand, the EMI shielding and thermal management performance should be further enhanced simultaneously to satisfy commercial requirements.…”