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Electronic textiles have become a dynamic research field in recent decades, attracting attention to smart wearables to develop and integrate electronic devices onto clothing. Combining traditional screen-printing techniques with novel nanocarbon-based inks offers seamless integration of flexible and conformal antenna patterns onto fabric substrates with a minimum weight penalty and haptic disruption. In this study, two different fabric-based antenna designs called PICA and LOOP were fabricated through a scalable screen-printing process by tuning the conductive ink formulations accompanied by cellulose nanocrystals. The printing process was controlled and monitored by revealing the relationship between the textiles’ nature and conducting nano-ink. The fabric prototypes were tested in dynamic environments mimicking complex real-life situations, such as being in proximity to a human body, and being affected by wrinkling, bending, and fabric care such as washing or ironing. Both computational and experimental on-and-off-body antenna gain results acknowledged the potential of tunable material systems complimenting traditional printing techniques for smart sensing technology as a plausible pathway for future wearables.

Additive manufacturing (AM) enables cost e↵ective production of complex shapes with providing design freedom. Fused deposition modeling (FDM) has been one of the most accessible AM methods which guide thermoplastic filaments to provide accurate and easy production of 3D objects layer by layer fusion. However, this technique has brought some drawbacks associated with limited material choices including relatively weak structural properties, low resolution range, and restrained processability in 3D printers. To overcome these flaws of FDM, herein we described the fabrication of high-performance thermoplastic filaments as an FDM feedstock as a stronger replacement of commodity thermoplastics. For further improvement, carbon nanotubes (CNTs) were incorporated into high performance matrices to provide multifunctionality both by improving mechanical properties and electrical conductivity. To achieve that, composite polyetherimide (PEI) filaments with various CNTs fractions were processed by melt compounding without any solvents or additives. Manufacturing process adopted a sequence of twin and single screw extrusion. Thermal transition and rheological changes due to CNTs incorporation were monitored and morphology, tensile behavior and electrical conductivity of neat PEI and nanocomposite filaments were investigated. The results showed that 5 wt % CNTs reinforced PEI filaments exhibited 55 % higher sti↵ness compared to neat PEI feedstock. Structural analysis supported that these nanofillers were well dispersed in mix state and electrical percolation threshold of CNTs/PEI nanocomposite filaments was found as low as ca. 0.1 wt % CNTs.

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