Conductive Polyester Fabrics with High Washability as Electrocardiogram Textile Electrodes

Textile electrodes for electrocardiogram (ECG) acquisition should be highly surface conductive and resistant to deterioration during the use of smart clothes in washing, stretching, and bending. In order to obtain conductive fabrics with great potential for practical application in ECG acquisition, thiol groups grafted polyester fabrics were coated with a condensed silver layer via electroless plating, where the electrical resistance was as low as 7.18 mΩ/sq. The stability of the conductive coating on the fabric in application was studied in the process of elongation, bending, oxidation, and washing. Polyester fiber has a high elasticity, the silver layer presented fracture trend after elongation, and the electrical resistance reached 14.74 mΩ/sq after 20% elongation. The conductivity of the fabric was less affected by bending, and silver layer fell off a little after 3000 bending cycles. After being placed in a constant temperature and humidity environment, the electrical resistance was almost unchanged after 9 weeks. The surface square resistance of the fabric is 0.93 Ω/sq after 200 washing cycles because of the high adhesion of silver layer to the thiol groups modified fabrics. The textile electrodes were embedded in smart garment to capture the ECG signals of a human in running states. The ECG waveform was still clear after 200 washing cycles and the measured heart rate increased with the increase of movement speed. The excellent performance of as-prepared conductive fabrics shows the feasibility as textile electrodes in ECG acquisition for practical application.