Polypyrrole/poly(vinyl alcohol-co-ethylene) nanofiber composites on polyethylene terephthalate substrate as flexible electric heating elements

Polypyrrole/poly(vinyl alcohol-co-ethylene) (PPy/PVA-co-PE) nanofiber composites on polyethylene terephthalate (PET) substrates were prepared using spray coating technique and in situ polymerization process. The electric heating behaviors of composites were investigated as functions of the amounts of nanofiber and PPy. It was observed that, the electrical resistivity of composites decreased significantly with increasing nanofiber and PPy contents. Scanning electron microscope images and infrared spectrum studies confirmed the formation of well dispersed network-like structure of PPy/PVA-co-PE nanofibers on PET substrate. Furthermore, maximum temperature attained at a given applied voltage for the composites could be well controlled by changing nanofibers and PPy amounts. PPy/PVA-co-PE nanofiber/PET composites exhibited excellent electric heating performance in aspects of rapid temperature response, long retaining behavior, thermal and operational stability. The incorporation of PPy on PVA-co-PE nanofibers/PET nonwoven substrates resulted in high conductivity and enhanced heating behavior, which have potential to be used as efficient electric heating elements.