Incorporation of polyvinyl alcohol in bacterial cellulose/polypyrrole flexible conductive films to enhance the mechanical and conductive performance.

The integration of polypyrrole (PPy) into bacterial cellulose (BC) has provided significant conductivity and cost benefits. However, this combination has led to a reduction in mechanical properties, particularly in terms of elongation at break and tensile strength. This study investigated the enhancement of BC/PPy composite films by incorporating polyvinyl alcohol (PVA). The resulting BC/PPy/PVA films demonstrated improvements in flexibility, tensile strength and thermal stability. Specifically, with 7 % PVA, the flexible films exhibited remarkable enhancements: tensile strength increased from 11.01 MPa (for BC/PPy) to 25.27 MPa and elongation at break rose from 5.81 % to 11.54 %. Additionally, the electrical conductivity of the BC/PPy/PVA films with a resistance of 38.5 Ω, surpassed that of the BC/PPy films. Furthermore, the equilibrium swelling water absorption rates of BC/PPy and BC/PPy/PVA films were 30.6 % and 81.4 %, respectively, with corresponding resistances of 530 Ω and 540 Ω. The variation in resistance between the dry and swollen states of the BC/PPy/PVA flexible conductive film resulted in differences in the brightness of the small light bulb. These findings highlighted the synergistic effects of PVA within the BC/PPy matrix, presenting a promising avenue for developing high-performance conductive materials suitable for flexible electronics and wearable devices.