Piezoelectric Characterization of Boron Nitride Nanotube-Polyurethane Composites

Boron nitride nanotubes (BNNTs) have exceptional thermal stability, thermal conductivity, mechanical properties, neutron radiation shielding, and piezoelectricity. Due to their multifunctional properties, BNNTs are potential candidates for sensory materials in harsh environments. Brittleness and non-conformity of conventional piezoelectric ceramics have limited their broad applications. Flexible and ultra-light piezoelectric sensors based on BNNTs could be an alternative solution in high temperature, high radiation, high shock, and severe vibration environments. In this study, BNNT-Polyurethane (PU) composites were fabricated and their converse piezoelectric constant of d(33) was assessed using a laser Doppler vibrometer (LDV). This study demonstrated that BNNT could be an excellent piezoelectric nanofiller for flexible sensor applications.