Development of PANI-TPU/MWCNTs based nanocomposites for piezoresistive strain sensing applications

• TPU-PANI/MWCNTs blends were prepared by in-situ polymerization. • The Polyaniline and MWCNTs content affect the performance of conducting blend. • FTIR analysis confirms the interaction between the blend components. • Electrical properties of blend improve by adding conductive filler. • LCR testing was used to study the piezoresistive properties of TPU-PANI/MWCNTs. Thermoplastic polyurethane (TPU) nanocomposites were prepared containing multiwalled carbon nanotubes (MWNTs) and polyaniline (PANI) by an in-situ polymerization for piezoresistive strain sensing applications. TPU has the ability to sustain large strain. While the synergistic effect of PANI and MWCNTs increases the overall conductivity and mechanical flexibility of composites. The electrical resistivity and resistivity–strain behavior of these composites were measured. The results indicate that the concentration of MWCNTs drastically affects the conductivity of composites. The strain sensing properties of PANI-TPU/MWCNTs sensors show good recoverability and reproducibility over 10 cycles up to a strain of 20%. Composite having 1.2 wt % MWCNTs content, 15% Ani-DBSA at 30% strain demonstrated a gauge factor of 4.3.