3D-printed carrageenan-based nanocomposites for sustainable resistive sensing devices

Abstract

In the scope of natural based materials for sustainable technologies, this work reports on resistive sensors based on carrageenan composites with multi-wall carbon nanotubes (MWCNT). The materials were processed by direct-ink-writing with water as a solvent and mechanical, thermal and electrical property of printed composites have been tailored by varying filler content. It is shown that the inclusion of the carbonaceous fillers does not affect the morphology, polymer phase and the thermal properties of the polymer matrix. On the other hand, the Young modulus increases from 2 to 5 MPa, and the electrical conductivity from 8.3×10-6 up to 0.03 S·m-1 , with increasing filler content. The highest d.c. conductivity value, 0.03 S·m-1 , has been obtained for the MWCNT/Carrageenan composite with 5wt.% filler content. This composite has been evaluated as a piezoresistive sensor, showing high sensibility (57 Ω/N), excellent reproducibility, no hysteresis, and being stable for more than 100 cycles. This work demonstrates that it is possible to obtain high performance sustainable resistive sensing materials and devices based on carrageenan composites and produced by additive manufacturing.