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The electromagnetic pollution issues have been arising from the fast-growing development for electronic devices. Hence, the demand for materials with high electromagnetic interference (EMI) shielding performance has increased. Here, we developed self-healable, flexible and printable graphene oxide/silver nanowire films and textiles with excellent EMI shielding performance. The maximum electromagnetic interference shielding effectiveness (EMI SE) of 92 dB was recorded for an 18 μm-thickness film. In addition, the specific EMI shielding effectiveness was 31 dB cm3/g or 48,275 dB cm2/g when normalized to film thickness. Both values are higher than reported EMI shielding products. The composite film and coated textile were tolerant of damage induced by cracking or scratching. Damaging the films by cracking reduced the electrical conductivity, mechanical properties, and the EMI SE was decreased from 72 dB to 56 dB at 8.2 GHz. After the healing process, the EMI SE was recovered to 71 dB and mechanical properties restored. The EMI SE of textile reached a maximum of 30 dB which is suitable to use as a commercial EMI shielding product. In addition, the textile exhibited high flexibility, and showed excellent mechanical stability with no change in performance after 1000 bending cycles.

The need for thin and lightweight electromagnetic interference shielding materials is rapidly increasing in several industries, such as aerospace and telecommunication. This research finds that a shielding material, which is developed by the orthogonal pattern of spinnable multiwall carbon nanotubes (MWNTs), is ultra-light weight, thin, and has a high shielding effectiveness (SE). An orthogonal pattern, generated by just alignment of the spinnable MWNTs without adding any support materials such as polymers, ceramics, and magnets demonstrates that it is possible to efficiently attenuate electromagnetic interference (EMI) in the X-band frequency range (8.2–12.4 GHz). EMI SE in the developed shielding material is about 19.2 dB with a specific shielding effectiveness (SSE)/t (thickness) value of 73,633 dB cm2 g−1 at a thickness of about 4.48 μm. In addition, absorption effectiveness in this shielding material is as high as 96.3%, which provides excellent ability to reduce the secondary damage by reflection.

Yarn supercapacitors have attracted renewed interest as promising energy storage for wearable devices due to their lightweight, long cycling lifetime and excellent weavability. There has been much effort to fabricate high performance yarn supercapacitor by depositing pseudo-capacitive materials on the outer surface of the carbon fibers. However, a key challenge still remains to achieve high capacitance and high mass loading without sacrificing the cycling stability. Herein, we perform a phase-controlled of MnO2 at various deposition temperatures with ultrahigh mass loading of 11 mg/cm2 on a MWNT sheets and fabricate it to yarn structure to achieve high capacitance without decreasing in the electrochemical performance. The structure of optimized sample (MnO2/CNTs-60, deposition at 60 °C) consists of the composite of primary α-MnO2 nanosheets and secondary γ-MnO2 nanoparticles. The heteronanostructures of MnO2 provide facile ionic and electric transport in the yarn electrode, resulting in improvement of electrochemical performance and cycling stability. The MnO2/CNTs-60 yarn electrode with ultrahigh mass loading delivers a high areal capacitance of 3.54 F/cm2 at 1 mA/cm2 and an excellent rate capability. Finally, the MnO2/CNTs-60 device exhibits an outstanding high areal energy density of 93.8 μWh/cm2 at the power density of 193 μW/cm2, which is superior to previously reported symmetric yarn supercapacitors.

This research develops a unique material to attenuate electromagnetic interference (EMI) by using spinnable multiwalled carbon nanotubes (MWNTs) combined with bio-polydimethylsiloxane (PDMS) that contains BaTiO3 (MBPBT). In particular, a plaid pattern, formed by the spinnable MWNTs, is very effective in attenuating the propagation of EM waves,which achieves over 20 dB at 8.2–12.4 GHz (X-band frequency range). This means that a filter type of the spinnable MWNTs is actively able to handle the directionality and movement of EMI propagation. In addition, the MBPBT is characterized by its strong mechanical advantage (bending radius 180°).

A buckling structure is a crucial element for materials used in wearable electronics by taking a topographical approach to solve a spatial constraint. This review introduces various buckling structures, with the corresponding theory and fabrication, for the latest materials or devices, including secondary batteries, supercapacitors, sensors, organic thin film transistors, polymer light-emitting diodes, and organic light emitting diodes, all of which have attracted much attention recently in journals. This review demonstrates how various buckling structures can be practically integrated into functional materials to enlarge the active area, to enhance flexibility or stretchability, and to improve unique functionality itself without loss.

Thin and flexible electromagnetic shielding materials have recently emerged because of their promising applications in drones, portable electronics, and military defense facilities, etc. This research develops an electromagnetic interference (EMI) shielding material by a bi-directional lattice sandwich structure (BLSS) which is formed by liquid crystalline graphene oxide (LCGO) and an orthogonal pattern of spinnable multiwalled nanotubes (OPSM) in consideration of the movement of electromagnetic waves. The average EMI shielding effectiveness (SE) of the developed material with 0.5 wt % reduced LCGO (r-LCGO) and an OPSM composed of 64 layers was approximately 66.1 dB in the X-band frequency range (8.2–12.4 GHz, wavelength: 3.5–2.5 cm), which corresponds to a shielding efficiency of 99.9999%. Also, its absorption effectiveness is 99.7% of the total EMI SE, indicating that it has remarkable ability to prevent secondary damage induced by EM reflection. The specific EMI SE (SSE/t) of the composite material considering the contribution of thickness (t) ranged from 21,953 dB cm2 g-1 to 2,259 dB cm2 g-1.

Magnetically driven torsional actuation of a multiwalled carbon nanotube (MWNT) yarn was realized by first biscrolling NdFeB magnetic particles into helical yarn corridors to make a magnetic MWNT yarn. The actuating device comprised a pristineMWNT yarn that was connected to the magnetic MWNT yarn, with a paddle attached between these yarns. The application of a magnetic field reversibly drove torsional actuation of up to 80° within ∼0.67 seconds. This magnetic actuator was remotely powered, and its actuation stroke was the same when the muscle array was at 20 °C and at -100 °C.

Structural fire-protective clothing must be effective at minimizing the thermal effects of fire. However, water remaining on the outer shell might play an important role in conducting heat transfer, which causes skin burns in a firefighter when he douses a fire with water through a hose. Therefore, this research demonstrated the difference in the heat transfer and humidity created by the remaining water or lack of water on the outer shell under a condition in which the temperature (45 ± 1℃) of the external environment was higher than that of the skin. Two types of multilayered systems, which simulated real fire-protective clothing (outer shell, moisture barrier, thermal liner) were tested by using a human–clothing–environment (HCE) simulator. The experimental results verified that water on the outer shell increased the microclimate temperature in the structural fire-protective clothing. In particular, we assume that air permeability in the outer shell can be an important factor to control heat and mass transfer within the microclimate.

Yarn supercapacitors have attracted renewed interest as promising energy storage for wearable devices due to their lightweight, long cycling lifetime and excellent weavability. There has been much effort to fabricate high performance yarn supercapacitor by depositing pseudo-capacitive materials on the outer surface of the carbon fibers. However, a key challenge still remains to achieve high capacitance and high mass loading without sacrificing the cycling stability. Herein, we perform a phase-controlled of MnO2 at various deposition temperatures with ultrahigh mass loading of 11 mg/cm2 on a MWNT sheets and fabricate it to yarn structure to achieve high capacitance without decreasing in the electrochemical performance. The structure of optimized sample (MnO2/CNTs-60, deposition at 60 °C) consists of the composite of primary α-MnO2 nanosheets and secondary γ-MnO2 nanoparticles. The heteronanostructures of MnO2 provide facile ionic and electric transport in the yarn electrode, resulting in improvement of electrochemical performance and cycling stability. The MnO2/CNTs-60 yarn electrode with ultrahigh mass loading delivers a high areal capacitance of 3.54 F/cm2 at 1 mA/cm2 and an excellent rate capability. Finally, the MnO2/CNTs-60 device exhibits an outstanding high areal energy density of 93.8 μWh/cm2 at the power density of 193 μW/cm2, which is superior to previously reported symmetric yarn supercapacitors.

Highly deformable and electrically conductive fibres with multiple functionalities may be useful for diverse applications. Here we report on a supercoil structure (i.e. coiling of a coil) of fibres fabricated by inserting a giant twist into spandex-core fibres wrapped in a carbon nanotube sheath. The resulting supercoiled fibres show a highly ordered and compact structure along the fibre direction, which can sustain up to 1,500% elastic deformation. The supercoiled fibre exhibits an increase in resistance of 4.2% for stretching of 1,000% when overcoated by a passivation layer. Moreover, by incorporating pseudocapacitive-active materials, we demonstrate the existence of superelastic supercapacitors with high linear and areal capacitance values of 21.7 mF cm-1 and 92.1 mF cm-2, respectively, that can be reversibly stretched by 1,000% without significant capacitance loss. The supercoiled fibre can also function as an electrothermal artificial muscle, contracting 4.2% (percentage of loaded fibre length) when 0.45 V mm-1 is applied., The development of electrically conductive fibres is attractive for wearable electronics, but performance should be maintained upon deformation and tensile strain. Here the authors fabricate flexible, stretchable, carbon nanotube-coated spandex fibres for supercapacitors and artificial muscles.

Electroactive polymers (EAPs) have attracted attention in many fields such as robotics, sensors devices and biomedical devices. However, the practical application of these actuators has still problems due to incomplete reversibility and high applied voltage. In order to overcome these problems, in this study, we have shown actuator based on phase transition that is consisted of the carbon nanotubes yarn infiltrated with the mixture of elastomer and methanol. Our electrothermally driven hybrid coiled yarn muscle provides a work capacity of 0.49 kJ kg−1 and a tensile contraction of 30.5% within ∼3 s on an applied stress of 3.1 MPa at an applied DC voltage of 5 V. The maximum work capacity is under isobaric 23.4 MPa, which is 110 times that of typical mammalian skeletal muscles. This actuator may serve as a promising candidate for the practical use in soft robotics.

Asymmetric supercapacitors are receiving much research interests due to their wide operating potential window and high energy density. In this study, we report the fabrication of asymmetrically configured yarn based supercapacitor by using liquid-state biscrolling technology. High loading amounts of reduced graphene oxide anode guest (90.1 wt%) and MnO2 cathode guest (70 wt%) materials were successfully embedded into carbon nanotube yarn host electrodes. The resulting asymmetric yarn supercapacitor coated by gel based organic electrolyte (PVDF-HFP-TEA·BF4) exhibited wider potential window (up to 3.5 V) and resulting high energy density (43 μW h cm−2). Moreover, the yarn electrodes were mechanically strong enough to be woven into commercial textiles. The textile supercapacitor exhibited stable electrochemical energy storage performances during dynamically applied deformations.

Cable-type stretchable electrochemical pseudocapacitors based on multi-walled carbon nanotube (MWCNT) sheets and two different metal oxide nanopowders (NP), i.e., MnO2 and RuO2 are developed using a newly-devised dry painting method to mechanically fix the NP to the elastic rubber-based MWCNT electrode substrate, resulting in a porous buckling structured pseudocapacitor yarn. Highly stretchable stylene-ethylene/butylene-stylene (SEBS) is used as the supporting elastomeric core for wrapping with the MWCNT sheets and the electroactive NP. The dry painting can successfully deposit NP on the soft SEBS surface, which is normally an unfavorable substrate for coating alien materials. The resulting yarn-type pseudocapacitor, composed of eight-layered MWCNT sheets, three-layered RuO2, and two-layered MnO2, showing a diameter of approximately 400 μm with a porous buckling structure, records a specific capacitance of 25 F g−1. After being stretched by 200% in strain with no sacrifice of the porous buckling structure, the cable-type stretchable electrochemical pseudocapacitor yarn retains its electrical capacity, and is potentially applicable to energy storage devices for wearable electronics.

Functional clothing, sportswear and military uniforms, are mainly made of polyester or cotton fabrics for dealing with sweat absorption and heat transfer produced by the human body. The human body typically wears two or three garments, such as innerwear, T-shirt, and jacket, thus comprising a multilayered system. Garments’ responses to heat transfer and vapor flow differ depending on whether their physical structures are hydrophobic or hydrophilic. Hence, this study analyzes differences in heat transfer and vapor flow, induced by the human body covered with multilayered garment systems, consisting of three polyester or cotton layers. In particular, it verifies three differences in the heat transfer and relative humidity, amount of relative humidity, and response time of thermal equilibrium in multilayered systems by using a new measurement system, “H&M evaluation device”. Resultant data provide precise information regarding several differences in hydrophilic and hydrophobic multilayered fabric systems.

Ever since the spinning process was developed, numerous research studies have been conducted and many precision instruments have been developed to control the tension in moving yarn. These efforts, however, have remained insufficient because many factors that need to be considered have not been handled in an integrated manner. To overcome this limitation, various parameters that affect the tension must be examined and the relationships among them must be discovered. Hence, the present paper reviews a variety of parameters for yarn moving from a ring spinning machine to a winding machine. These two machines, in particular, involve a series of phenomena in which the yarn passes over a stationary surface. In addition, the relevant parameters related to force, tension, and yarn motion need to be separately investigated in each spinning section (e.g., the balloon, the section from the bobbin to the traveler, and the section from the bobbin to the unwinding package) and at each part (e.g., the traveler, yarn guide, package, and tensioner).

This paper reviews four factors involved in apparel and textile manufacturing procedures under international economic fluctuation. This work will be helpful to evaluate the efficiency of global manufacturing systems. Production costs including direct costs related to material and labor costs, and indirect costs associated with manufacturing running ones are significantly correlated to diverse visible and invisible elements such as infrastructure and the labor skills of foreign manufacturing areas, which might create an apparent difference in production costs. Manufacturers can consider how to improve the efficiency of manufacturing systems through a review of the co-relationship between manufacturing procedures and four factors such as manufacturing systems, production outsourcing types, manufacturing locations, and production costs in detail. In addition, the four factors are the core parameters of determining or contributing to the efficiency of a production schedule that is ultimately associated with the supply chain management (SCM) to efficiently conduct Quick Response (QR).

Chitosan is a safe and friendly substance for the human organism; therefore, it has become of great interest not only as an underutilized resource, but also as a new functional material of high potential in various fields. Some unique properties make chitosan an excellent material for the development of new industrial applications and recent progress in chitosan material is quite noteworthy. In this review, we mainly take a closer look at various chitosan applications and intend to provide interdisciplinary insight in the scientific knowledge immediately usable to realize fabrications. In addition, based on current research and existing products, some new approaches in this fascinating area are thoroughly discussed.