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Flexible wearable devices for various applications have attracted research attention in recent years. To date, it is still a big challenge to fabricate strain sensors with a large workable strain range while maintaining their high sensitivity. Herein, we report the fabrication of highly sensitive wearable strain sensors from braided composite yarns (BYs) by in situ polymerization of polypyrrole (PPy) on the surface of yarns after polydopamine templating (BYs-PDA). The electromechanical performance and strain sensing properties of the fabricated braided composite yarn@polydopamine@polypyrrole (BYs-PDA-PPy) were investigated. Because of the unique braided structure of BYs, the BYs-PDA-PPy strain sensors exhibit fascinating performance, including a large workable strain range (up to 105% strain), high sensitivity (gauge factor of 51.2 in strain of 0%-40% and of 27.6 in strain of 40%-105%), long-term stability and great electrical heating performance. Furthermore, the BYs-PDA-PPy sensors can be used in real-time monitoring subtle and large human motions. The BYs-PDA-PPy strain sensors can also be woven into fabrics for large area electric heating. These results demonstrate the potential of BYs-PDA-PPy in wearable electronics.

The development of wearable electronic devices has greatly stimulated the research interest of textile-based strain sensors, which can effectively combine functionality with wearability. In this work, the fabrication of highly stretchable and compressible strain sensors from weft-knitted spacer fabric was reported. Carbon nanotubes and polypyrrole were deposited on the surface of fabric via an in situ polymerization approach to reduce the electrical resistance. The as-fabricated WSP-CNT-PPy strain sensor exhibits high electrical conductivity and stable strain-sensing performance under different stretching deformations. The WSP-CNT-PPy strain sensor can be stretched up to 450% and compressed to 60% with a pressure of less than 50 KPa, which can be attributed to the unique loop and interval filament structures. The distinguishing response efficiency of WSP-CNT-PPy can effectively detect faint and strenuous body movements. In addition, the electrochemical behavior of WSP-CNT-PPy was also characterized to study the comprehensive properties. The electro-heating performance was also evaluated for feasible Joule heater applications. This work demonstrates the practicability of WSP-CNT-PPy strain sensor fabric for real-time monitoring in promising wearable garments. [ABSTRACT FROM AUTHOR]

The development of cooling textiles has a significant impact on energy saving and cost‐effectiveness in the context of global warming. Engineering textiles with cooling performance while maintaining their intrinsic traits, for example, lightweight, washable, comfort, and durability, is a great challenge in developing personal cooling garments. Here, the synthesis of nanodiamond/polydopamine/wool (ND‐PDA‐wool) nanocomposites through a facile dip‐coating approach is demonstrated. Different types of ND including detonation ND (DND), carboxylated ND (ND‐COOH) and hydroxylated ND (ND‐OH), are used, and dopamine templating is applied to achieve strong adhesion and bonding between fiber and ND. The morphology, structure, and properties of the as‐coated fabrics are characterized, and the cooling performance together with comfort are measured. Due to the excellent thermal conductivity of ND, the temperature difference between the coated fabrics and uncoated ones is around 2.4–3.9 °C within a short time span of 30 min. The coated ND‐PDA‐Wool fabrics demonstrated enhanced thermal stability and improved mechanical properties with excellent durability, and the water absorbency is greatly enhanced with well‐maintained air permeability. ND‐PDA‐wool composite fabrics offer a strategy to develop durable, lightweight, washable, and comfortable cooling textiles with immense potential in energy saving and reducing space cooling costs. [ABSTRACT FROM AUTHOR]

This work aims to develop durable functional cotton fabrics by growing zinc oxide (ZnO) nanoparticles on polydopamine (PDA) templates. ZnO nanoparticles were grown on the PDA-templated cotton fabrics by the hydrothermal method at room temperature. The surface morphology, chemical composition, and crystalline structure of the ZnO-coated cotton fabrics were characterized by scanning electron microscope (SEM) with energy dispersive X-ray analysis (EDX), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The ZnO nanoparticles were found to disperse evenly on the surface of cotton fabrics. The ultraviolet (UV) protection factor (UPF) value of the ZnO-coated cotton fabrics was maintained at 122.5, and 99% reduction in bacterial load was observed against Gluconobacter cerinus even after five cycles of laundering. The PDA was found to be effective in fixing the ZnO seeds tightly on the surface of cotton fabrics, resulting in excellent durability of the coating of ZnO nanoparticles. [ABSTRACT FROM AUTHOR]

• Different kinds of plied yarns were used to fabricate crochet fabric sound absorber. • Both plied yarns and multilayer configurations determine the sound absorption efficiency. • Monolayer crochet fabric exhibited the sound absorption coefficient as high as 0.57, and the value of multilayer structure is 0.80. This work has provided an experimental study on the sound absorption properties of crochet fabrics. Four kinds of three-plied, four-plied, five-plied, and six-plied yarns were used in the study due to their different structural features. The porous structure and acoustical characteristic of fabricated crochet fabrics were characterized. The effects of different multi-layer structures and plied yarns on sound absorption were also further investigated using impedance measurement tube method. It has been found that both plied yarns and multilayer configurations can significantly determine the sound absorption efficiency. The results indicated that the absorption coefficient of monolayer crochet fabric with six-plied yarns is 0.57, and all the multilayer crochet fabrics exhibited the absorption coefficient of higher than 0.65. In summary, this work has demonstrated that crochet fabrics with good sound absorbability is promising for potential noise reduction and control applications in interior decorations. [ABSTRACT FROM AUTHOR]