Spacer Knitted Structures Coated with Polyaniline: A Quality Assessment for Use in Wearables

Wearables have received considerable attention due to their ability to monitor physiological and environmental data in real time. Their performance depends on innovative structures and materials that respond to diverse stimuli. A major challenge is to provide flexibility and breathability. In this context, textiles with intrinsically conducting polymers (ICPs), such as polyaniline (PANI), show great potential. This study aimed to develop a conductive material for wearable textiles through the in situ polymerization of PANI on the surface of a spacer weft-knitted fabric. Different concentrations of aniline (ANI) solution (0.05, 0.10, and 0.20 mol·L−1) were used. Analyses included thermal characterization, electrical conductivity tests, and electromechanical evaluations under compression–decompression cycles. Usability simulation tests included washing fastness, abrasion resistance, tensile strength, and perspiration tests. Samples coated using 0.10 mol·L−1 ANI exhibited the best overall performance, combining good conductivity, coating uniformity, and electromechanical stability. Morphological analyses confirmed the homogeneous deposition of PANI, while mechanical tests revealed increased tensile strength and a slight increase in material stiffness. Thermal characterization indicated slight reduction in transition temperatures associated with the presence of the polymer. Overall, the PANI-coated knitted fabric demonstrated strong potential for smart textile applications, particularly in flexible wearable textiles.