Properties of polyvinylidene difluoride-carbon nanotube blends

Single-walled and multiwalled carbon nanotube blends with polyvinylidene difluoride (and its copolymers) have been characterized. The nanotubes are observed to form a well-dispersed, structurally random nanophase within the fluoropolymer matrix. X-ray analysis coupled with differential scanning calorimetry suggests that the nanophase alters crystal formation within the polymer. For most loadings and nanotube types, the piezoelectric beta-polymorph is significantly enhanced over other crystal phases. Solution-cast composite thin films exhibit enhancements in both the pyroelectric response and mechanical transduction over pure polymer. This is interpreted as resulting from the change in crystallinity.