Nanomechanical properties of PVDF-ZnO polymer nanocomposite

Poly(vinylidenefluoride)-ZnO (PVDF-ZnO) nanocomposites with mechanically activated ZnO nanoparticle fillers were investigated using thermal and mechanical analysis and AFM and PFM. Differential scanning calorimetry (DSC) investigated the effect of ZnO nanoparticles on the crystallinity of the polymer, under controlled heating and cooling. Atomic force (AFM) microscopy was used to record the surfaces of the samples. Nanocomposite surface roughness shows the presence of the different phases inside of the matrix, where rough samples contain a higher proportion of the beta phase. PFM was performed to investigate the piezoresponse of the composites. Nanoidentation showed that the mechanical activation of the filler (ZnO) increases the Young modulus with the activation time. Molecular simulations in periodic systems (PVDF-ZnO spherical nanocluster and nanocylinder composite) were used to investigate the influence of particle size and shape on the Young modulus of different phases of PVDF.