Mechanical, in-situ electrical and thermal properties of wearable conductive textile yarn coated with polypyrrole/carbon black composite

Abstract

Smart electronic textiles integrate the advantages of flexibility in textiles and the capability of electronics in a wearable form for biomedical monitoring, energy and sensing applications. This work investigated mechanical, in situ electrical properties, and thermal conductivity of polypyrrole/carbon black composite coated cellulose (cotton) yarn. An inexpensive and straightforward coating method of pre-treatment, dipping, and drying was reported. Mechanical properties on the bare and coated cotton yarn were determined from the stress versus strain response. The coated yarn is mechanically stable with the tensile strength of ∼11.6 N. The resistivity and conductivity properties of the yarn are measured from the linear response of the I–V curve, showing an ohmic behavior. The improvement was observed in electrical conductivity from 11.4 to 12.6 s m−1 as the force is varied from 1–2 N at .5 N intervals. Characterization of the coated surface was done to check for the coating uniformity using scanning electron microscopy. Transient-hot-bridge method was used to measure the thermal conductivity of coated and uncoated cotton fabric. Thermal conductivity for coated fabric was measured to be 0.12 W m−1 K−1 at ambient temperature.