Investigation of structural and thermal characteristics of PVDF/ZnO nanocomposites

Zinc Oxide PVDF Nano‐Composites–Tuning Interfaces toward Enhanced Mechanical Properties and UV Protection

“…The non-isothermal crystallization data, obtained from the DSC, demonstrate the heterogeneous nucleating activity of the NPs associated, with a shift of the crystallization temperature toward higher temperatures (Figure 4). [38] At the slowest cooling rates of 5 and 10 C min À1 , PVDF was found to crystallize much faster (by up to 40%) in the presence of the ZnO NPs, highlighting again the nucleating ability of the ZnO (Figure 4). This effect was, however, not so pronounced at higher cooling rates potentially due to the higher quenching of the material, due to the sharply increased viscosity of the dope.…”

“…This result is also consistent with the quantitative infra-red analysis of the films, showing that the ratio of the a-crystal phase increased from 64.7 to 68.8% prior to being reduced down to 60.6% ( Figure S3). [38,39] The sharp reflection peaks of ZnO at 31.9 , 33.5 , and 36.2 of 2u visible in both injection molded samples and films, increased gradually in intensity as the ZnO content increased, indicating the presence of phase separated crystalline aggregates across the sample. [25,31,36] This is supported by recent results showing that reduced drawing speeds during the processing of PVDF nano-composites, with clay led to a ato b-crystal transition.…”

“…The high surface area of the ZnO nano-particles, and therefore, provided sites for crystal nucleation and potentially Van der Waals forces. [38,39] The sharp reflection peaks of ZnO at 31.9 , 33.5 , and 36.2 of 2u visible in both injection molded samples and films, increased gradually in intensity as the ZnO content increased, indicating the presence of phase separated crystalline aggregates across the sample. For this reason, the extent of the ZnO dispersion throughout the samples was also analyzed from the cross-sectional FIB-SEM images.…”

“…The scale of the aggregates (%250 nm) relative to the thickness of the films (%100 mm) suggests that the aggregates can potentially act as stress concentration sites and that the mechanical performance is no longer controlled by the polymer-filler interfacial interaction. Furthermore, although PVDF ZnO nanocomposites were previously processed by solution mixing, [38] the current report is the first of its kind to present a simple and efficient non-solvent based method to homogeneously incorporate nanoscale ZnO nano-particles across hydrophobic PVDF matrixes. The reason is likely related to the difficulty to achieve high dispersion of particles across such hydrophobic matrix.…”

Fabrication and Characterization of Zinc Oxide-Based Electrospun Nanofibers for Mechanical Energy Harvesting

“…Piezoelectric material-based NGs may play an important role because they can scavenge mechanical energy and transform it into a more flexible form, such as electrical energy. To date, piezoelectric materials based on PZT (lead zirconate titanate) [1][2][3], BaTiO 3 [4,5], polyvinylidene difluoride (PVDF) [6,7], BNT (bismuth sodium titanate) [8], and zinc oxide (ZnO) [9][10][11][12][13][14][15][16][17][18][19][20] have been the most widely investigated ones for use in transducers, actuators, transformers, photonics, optoelectronics, and sensors. However, fiber-based piezoelectric NGs [21][22][23] have not been extensively developed for keyboards because they must be resistant to large mechanical loads.…”