Tunable dielectric characteristics of TPU/PPy composite film and foamyfilm with low loss over a wide range of temperature

In the present research, thermoplastic polyurethane/polypyrrole (TPU/PPy) dielectric composites film and the lightweight foamyfilm are fabricated using the most simplified solvent casting and modified phase separation water immersion techniques, respectively. The establishment of chemical interaction and morphological investigations of the fabricated systems are analyzed by Raman spectroscopy and field emission scanning electron microscope (FESEM), respectively. Various dielectric properties, together with complex impedance, are determined over a wide range of frequencies (1 Hz-1 MHz) and temperatures (25 degrees C-120 degrees C). Most interestingly, above 30 Hz frequency, a significantly low value (<0.1) dielectric loss tangent (tan delta) is obtained at ambient temperature. A 90:10 foamyfilm exhibits a dielectric permittivity (epsilon') and tan d of 236 and 0.05 at 50 Hz frequency, respectively. Both 90:10 film and foamyfilm systems exhibit a significantly increasing trend of epsilon ' as well as low tan d with an increase in temperature over a wide range of frequencies. The thermogravimetric analysis (TGA) results of the 90:10 film and foamyfilm indicate the superior thermal stability of the 90:10 foamyfilm system. Based on the obtained low dielectric loss, the fabricated dielectric film, and foamyfilm can be employed in energy storage and high-temperature sensing applications.

Automated summary

Thermoplastic polyurethane/polypyrrole (TPU/PPy) dielectric composites film and lightweight foamyfilm were fabricated using simplified solvent casting and modified phase separation water immersion techniques. Chemical interaction and morphological investigations were analyzed through Raman spectroscopy and field emission scanning electron microscope (FESEM), respectively. The dielectric properties, including complex impedance, were determined over a wide range of frequencies and temperatures. The fabricated films exhibited low dielectric loss and can be used in energy storage and high-temperature sensing applications.