Improved Tensile Strength and Ferroelectric Phase Content of Self-Assembled Polyvinylidene Fluoride Fiber Yarns

An electrospinning method to obtain well-aligned self-assembled PVDF fibers in the form of yarn structures is presented. Post-treatments such as stretching at 100 degrees C and annealing improve the tensile modulus and strength of the fibers by 17 and 41%, respectively. The results reveal that post-treatment on fiber yarns induce crystallinity and beta-crystalline phase formation, which in turn impart a noticeable effect on the strength and stiffness of the fibers. An approximate to 10% improvement in the ferroelectric beta-crystalline phase fraction is estimated for the post-treated yarns. Such yarn structures with improved strength and ferroelectric beta-phase content can be useful for nanoscale and microscale electronic devices.