Polyamide/bacterial cellulose nanocomposite films for touchscreen applications

Abstract

The flexible piezoelectric film of polyamide 11 (PA11)/bacterial cellulose (BC) was successfully prepared via a solution casting method and compressed to a thin film. The various weight percentage of extracted BC (0.2, 0.4, 0.6, 0.8, 1 wt% for PA11 and 1 wt% for PA6) were incorporated into PA11 matrix using formic acid as a solvent. The results indicated that the higher amount of BC can slightly increase the thermal stability, crysllinity and mechanical properties of the nanocomposite films. Besides, the dielectric constant was enhanced to 24% compared to that of neat PA11 due to the interfacial polarization between the interfaces of fiber and polymer matrix. Consequently, the noncentrosymmetry structure of odd-numbered polyamide and the dipole orientation under an applied field induce the polarization yielding the good dielectric and piezoelectric properties. The tensional behavior of nanocomposite films was also improved with the increase in Young’s modulus from 678 to 749 MPa compared to neat PA11, However, the obtained films were less transparent. This nanocomposite film can further develop to be an alternative motional for the touchscreen sensor.