Dielectric Response Triggered by a Non-ferroelectric Phase Transition in Poly(Vinylidene Fluoride)/Poly(Ethylene Glycol)/Halloysite Composites

Thermoresponsive dielectric materials have attracted the interest of researchers as they exhibit very important application prospects in stimuli-responsive smart devices. In this contribution polyethylene glycol (PEG), impregnated in halloysite nanotubes (HNTs), was incorporated into poly(vinylidene fluoride) (PVDF) for tailoring the thermoresponsive dielectric properties based on a non-ferroelectric phase transition. The PVDF/PEG/HNTs displayed a remarkable rise of dielectric constant between 20 and 30 degrees C. The mechanism is related to the enhanced orientational polarization effect triggered by the solid-liquid phase transition of the PEG. This make it possible to design stimuli-responsive smart materials through a simple, low-cost and efficient strategy. The present work provides an alternative and innovative routine for tailoring thermal-induced dielectric behaviors via a non-ferroelectric phase transition by introducing PEG into a high-dielectric-constant polymer matrix.