Autonomous Triboelectric Smart Textile Sensor for Vital Sign Monitoring.

Wearable smart textile sensors for monitoring vital signs are fast, noninvasive, and highly desirable for personalized health management to diagnose health anomalies such as cardiovascular diseases and respiratory dysfunction. Traditional biosignal sensors, with power consumption issues, constrain the use of wearable medical devices. This study introduces an autonomous triboelectric smart textile sensor (AUTS) made of reduced graphene oxide/manganese dioxide/polydimethylsiloxane (RGO-M-PDMS) and polytetrafluoroethylene (TEFLON)-knitted silver electrode, offering promise for vital sign monitoring with self-powering, flexibility, and wearability. The sensor exhibits impressive output performance, with a sensitivity of 7.8 nA/kPa, response time of ≈40 ms, good stability of >15,000 cycles, stretchability of up to 40%, and machine washability of >20 washes. The AUTS has been integrated to the TriBreath respiratory belt for monitoring respiratory signals and pulse strap for pulse signals concurrently at different body pulse points. These sensors wirelessly transmitted the acquired biosignals to a smartphone, demonstrating the potential of a self-powered and real-time vital sign monitoring system.

Industrially Scalable Piezoresistive Smart-Textile Sensor for Flexible Electronics Application.

Industrially scalable pressure-sensitive smart textile sensors have been developed using graphite-polyurethane (G-PU) composite materials by the plasma-assisted dip-pad-dry-cure method. The advantage of this technique is that it is easy, simple, and suitable for high-volume production with industrially available machinery. The sandwich structure sensor has been constructed with the pressure-sensitive textile semiconductor and embroidery electrodes for manufacturing a single sensor and sensor matrix, which can detect touch, pressure, movement, etc., and send information wirelessly (via smartphone) to the user in real-time. The sensibility, hysteresis behavior, repeatability, and stability against washing, martindale abrasion, etc. of the piezoresistive polyester (PES) textile sensor have been optimized by the plasma-assisted semiconductive coating. The smart textile sensor built into this work provides flexibility, breathability, and wearability and can be easily integrated into wearable items allowing for object detection by scanning their weight, movement, interactive floor mate, and seat sensor mate for dynamic posture detection and sensor hand glove to translate finger movement into sign language (e.g., text or audio able). All necessary electronics and software associated with the relevant application have been developed to demonstrate the effectiveness of the products in a real-world demonstration, which encourages the widespread use of smart textile piezoresistive sensors for a variety of applications in flexible electronics sectors.

Advanced and Smart Textiles during and after the COVID-19 Pandemic: Issues, Challenges, and Innovations.

The COVID-19 pandemic has hugely affected the textile and apparel industry. Besides the negative impact due to supply chain disruptions, drop in demand, liquidity problems, and overstocking, this pandemic was found to be a window of opportunity since it accelerated the ongoing digitalization trends and the use of functional materials in the textile industry. This review paper covers the development of smart and advanced textiles that emerged as a response to the outbreak of SARS-CoV-2. We extensively cover the advancements in developing smart textiles that enable monitoring and sensing through electrospun nanofibers and nanogenerators. Additionally, we focus on improving medical textiles mainly through enhanced antiviral capabilities, which play a crucial role in pandemic prevention, protection, and control. We summarize the challenges that arise from personal protective equipment (PPE) disposal and finally give an overview of new smart textile-based products that emerged in the markets related to the control and spread reduction of SARS-CoV-2.

Super tough bilayer actuators based on multi-responsive hydrogels crosslinked by functional triblock copolymer micelle macro-crosslinkers.

Intelligent hydrogels responsive to external stimuli have been widely studied due to their great potentials for applications in artificial muscles, soft robotics, sensors and actuators. However, the weak mechanical properties, narrow response range, and slow response speed of many responsive hydrogels have hindered practical applications. In this paper, tough multi-responsive hydrogels were synthesized by using vinyl-functionalized triblock copolymer micelles as macro-crosslinkers and N-isopropyl acrylamide (NIPAM) and acrylamide (AAm) or 2-(dimethylamino)ethyl methacrylate (DMAEMA) and 2-acrylamido-2-methyl-1-propane-sulfonic acid (AMPS) as monomers. The P(NIPAM-co-AAm) hydrogels presented tensile strength of up to 1.6 MPa and compressive strength of up to 127 MPa and were tunable by changing their formulations. Moreover, the lower critical solution temperature (LCST) of the thermosensitive hydrogels was manipulated in a wide range by changing the molar ratio of NIPAM to AAm. Responsive hydrogel bilayers were fabricated through a two-step synthesis. A second layer of P(DMAEMA-co-AMPS) was synthesized on the first P(NIPAM-co-AAm) layer to obtain a bilayer hydrogel, which was responsive to temperature, pH and ionic strength changes to undergo fast and reversible shape transformation in a few minutes. This kind of strong and tough multi-responsive hydrogel device has broad prospects in soft actuators.