Low-Cost, Large-Area, Stretchable Piezoelectric Films Based on Irradiation-Crosslinked Poly(propylene)

Low cost, large area, lightweight, stretchable piezoelectric films, based on space‐charge electret with a foam structure (i.e., ferroelectrets or piezoelectrets), have been fabricated by using commercially available irradiation cross‐linked poly(propylene) (IXPP) foam sheets. Piezoelectric d33 coefficients are as high as 100 pC · N−1. The piezoelectric performance in such IXPP films is well preserved for repeated strains of less than 10%. Piezoelectric d33 coefficients are frequency independent in the range from 2 to 100 Hz. Such new class materials may be applied in sensory skins, smart clothing, bio‐inspired systems, microenergy harvesters, and so on. The preparation of lightweight, large‐area, low‐cost, thin, and stretchable IXPP ferroelectret films is presented and their piezoelectric performance is studied. A possible industrial procedure for the fabrication of stretchable piezoelectric sensor array films is suggested.