Synthesis of conductive yarn to develop wearable electronic device

The demand for soft, flexible, and conformable devices that may offer electrical functionality along with the benefit of comfort is increasing with the emergence of wearable electronic devices in our daily lives. Electronic textiles (e-textile) fabrics have electronic components embedded in them and can be worn. This textile must be conformal to the body, and also smart. This article proposes the synthesis of a conductive yarn that can be knit together to textiles to fabricate a smart textile with integrated electronic capabilities, which can be used as a sensor that detects critical parameters from human body. The proposed conductive yarn has been synthesised from cotton yarn, utilising the simple dip-immersion, and drying technique. Different forms of carbon materials, such as activated carbon (AC), carbon nanotubes (CNTs), and graphite are used as conductive elements with polyvinyl acetate and deionised water as solvent. The conductive elements and the solvent are combined to prepare the conductive solution. The experiment has been carried out by varying yarn thickness and composition of conductive material with fixed yarn length. The coated yarns were analysed by developing their mathematical model using the linear fit technique. The change in resistance per unit length of the yarn was computed as the slope (kΩ/cm). The mathematical model of optimised conductive yarn is derived as y=4.535x+1.93 with a conductivity of 4.17 S/m. The experimental work proves that a commercially available cotton yarn can be infused with electrical properties by coating it with a conductive material. Additionally, it has also been observed that textile-based wearable devices are possible to fabricate with simple and cost-effective techniques.