Highly stretchable conductive fabric using knitted cotton/lycra treated with polypyrrole/silver NPs composites post-treated with PEDOT:PSS

Flexible sensors and wearable electronics have become important in recent years. A good conductive and flexible textile is needed to develop a commercial wearable device. Conductive polymers have generally been used with limitation in reducing the surface resistance to a certain amount. In this research, a method for fabricating a stretchable highly conductive cotton/lycra knitted fabric is introduced by treating the fabric with polypyrrole (PPy), silver nanoparticles (SNPs) composites, and post-treating with poly (3,4-ethylenedioxythiophene) poly (styrenesulfonate) (PEDOT:PSS). Polypyrrole and SNPs were in situ fabricated on the cotton/lycra fabric by consecutive redox reaction of silver nitrate and pyrrole and finally covered by PEDOT:PSS solution through dip-coating. The coated textile was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), X-ray mapping, and energy dispersive X-ray spectroscopy (EDX). Fourier transform infrared spectroscopy confirmed PPy-SNPs (P-S) composites on the fabric surface. Fourier transform infrared spectroscopy results, X-ray mapping, EDAX, and XRD analysis also confirmed the P-S composites and PEDOT:PSS polymeric layer on the fabric. Morphological observation showed a layer of PEDOT:PSS on the P-S caused the higher connection of coating on textiles which resulted in the higher electrical conductivity (43 s/m). Also morphological observations showed penetration of the silver particles inside fibers which represented improving in attachment and stability of the coating on the fibers. Further, the electrical conductivity of PPy-SNPs-PEDOT:PSS coated textile increased under the tension. Hence, the stretchable and highly conductive knitted cotton/lycra fabric has potentiality to be used for fabricating the flexible sensors or wearable electronics.