In Chapter 5, we discussed poly(vinylidene fluoride) (PVDF) as a popular matrix material for nanocomposites with high dielectric performances. In particular, because of its high polarization, piezoelectricity, and pyroelectricity, ferroelectric β-phase has been extensively studied. β-phase is widely considered the most useful PVDF structures contributing to the high energy storage and sensitivity to external stimuli. However, the crystal structure in PVDF also accounts for the biggest disadvantage of PVDF homopolymers: the high dielectric loss caused by dipole switching. This has been the major obstacle to the practical applications of PVDF-based materials in related energy and electronic applications.