Properties Of Poly Vinylidene Fluoride Composites Research Articles

On 3D printed polyvinylidene fluoride-based smart energy storage devices

Polyvinylidene fluoride (PVDF) is one of the established thermoplastics with inherent piezoelectric characteristics. In the past two decades, a lot of work has been reported on the use of virgin Polyvinylidene fluoride thermoplastics for sensing applications. But hitherto little has been reported on 3D printing of secondary (2°) recycled Polyvinylidene fluoride as a smart energy storage device (ESD). This work is focused on exploring the possibilities for 3D printing of smart energy storage device comprising of Polyvinylidene fluoride having (melt flow index (MFI) 30 g/(10 min) as per ASTM D 1238) reinforced with MnO2, graphite, ZnCl2, and N [Formula: see text] Cl in different weight proportions to form a feedstock filament for fused deposition modeling (FDM) in the first stage. The MFI of Polyvinylidene fluoride composites reinforced with MnO2, graphite, ZnCl2, and N [Formula: see text] Cl (34.095, 8.480, 42.982, 11.807 g/(10 min) respectively) was ascertained for possible 3D printing on FDM. The results suggest that even with an acceptable MFI of prepared 2° recycled Polyvinylidene fluoride, the same was not printable. Further for possible 3D printing on FDM, low-density polyethylene (LDPE) was blended in a Polyvinylidene fluoride matrix, and successful 3D printing-based energy storage device was prepared in the second stage. The study also highlights the mechanical, and morphological properties of Polyvinylidene fluoride composites have been improved after processing with a twin-screw extruder (TSE) by using different input parameters (screw temperature (T), screw speed (S), and load (L)). Overall, the study suggests that the proportion of LDPE, MnO2, graphite, ZnCl2, and N [Formula: see text] Cl has a significant effect on the rheological, mechanical, and morphological properties. The results have been supported with scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and Fourier-transformed infrared spectroscopy (FTIR) analysis.

Combined effect of hybrid carbon fillers on the physical and rheological properties of polyvinylidene fluoride composites

Combined effect of hybrid carbon fillers on the physical and rheological properties of polyvinylidene fluoride composites

The effect of core-shell BaTiO3@SiO2 on the mechanical and dielectric properties of PVDF composites

ABSTRACT In this study, polymer composite films were prepared by the solution casting method using ceramic filler barium titanate (BT) to enhance the mechanical and dielectric properties of polyvinylidene fluoride (PVDF). A silicon dioxide (SiO2) shell was coated on BT surface by hydrolysis reaction of tetraethyl orthosilicate (TEOS) at different concentrations in order to provide a strong interface between PVDF and BT. The influence of SiO2 coating on morphology, structure, thermal, tensile and dielectric properties of composites were investigated compared to neat PVDF. The results of analyses show that SiO2 is successfully coated on BT and that the ceramic filler enhances the tensile and dielectric properties of the composites. At low BT concentrations (5 and 10 vol.%) the tensile strength and Young modulus are improved compared to neat PVDF. For films having a high content of SiO2, in particular, coated BT high values, such as 24.8 at 102 Hz are found for the dielectric constant, which is greatly improved by almost 2.3 times compared to neat PVDF. Properties, such as flexibility and thermal stability, are well retained in the prepared composites.

Fabrication and Piezoelectric Properties of Polyvinylidene Fluoride Composites with High β Phase

Fabrication and Piezoelectric Properties of Polyvinylidene Fluoride Composites with High β Phase

Effects of suface hydroxylated strontium titanate nanofibers on dielectric and energy storage properties of polyvinylidene fluoride composites

With the rapid development of the electronics industry, the dielectric materials with high energy storage density, fast charge and discharge speed, easy-to-process and easy-to-mold, and stable performance are urgently needed to meet the requirements for lightweight and miniaturization of electronic component equipment. Dielectric ceramics has a high dielectric constant, but low breakdown field strength. Polyvinylidene fluoride (PVDF) has the advantages of good flexibility, high breakdown field strength, and light weight, but its dielectric constant is low. Achieving the ability to tailor the interface between dielectric ceramics filler and PVDF polymer matrix is a key issue for realizing the desirable dielectric properties and high energy density in the nanocomposites. As a result, much effort has been made to prepare the polymer composites through the surface modification of the nanoparticles with high dielectric constant fillers dispersed in a matrix, with the hope of preparing composites containing the high dielectric constant of the ceramic fillers and the high breakdown strength of polymers. In this work, in order to obtain the high dielectric-constant and high-energy-storage-density dielectric ceramics, the electrospinning method is used to prepare the SrTiO<sub>3</sub> one-dimensional nanofibers as the inorganic fillers and the casting method is adopted to prepare PVDF as the polymer matrix. To improve the interface between inorganic nanofiber fillers and PVDF matrix, the SrTiO<sub>3</sub> nanofibers are modified by surface hydroxylation. The effects of suface hydroxylated SrTiO<sub>3</sub> nanofibers on the dielectric properties and energy storage properties of PVDF composites are studied. The correlation between interface modification and energy storage performance of composites is investigated to reveal the mechanism of enhanced energy storage performance of SrTiO<sub>3</sub> nanofibers/PVDF composites. The results show that the dispersion of surface-hydroxylating SrTiO<sub>3</sub> nanofibers in PVDF polymer can be improved. The composites exhibit improved dielectric properties and enhanced breakdown strength. When the filling quantity of the surface-hydroxylating SrTiO<sub>3</sub> nanofiber fillers is 2.5 vol%, the energy storage density of the composite reaches 7.96 J/cm<sup>3</sup>. Suface-hydroxylating SrTiO<sub>3</sub> nanofibers exhibit excellent dispersion in the PVDF polymer matrix and strong interfacial adhesion with the matrix, leading the composites to possess excellent dielectric constant and energy storage performance. The surface hydroxylation of ceramic fillers can improve the energy storage performance of the composites.

Excellent dielectric properties of Polyvinylidene fluoride composites based on sandwich structured MnO2/graphene nanosheets/MnO2

MnO2/graphene nanosheets/MnO2 (MGM) is fabricated by a facile and effective ethanol-assisted graphene-sacrifice reduction method. The morphology and structure of the MGM are examined by scanning electron microscopy, transmission electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. The MGM is used as a dielectric filler to prepare MGM/Polyvinylidene composites by solution casting and hot pressing. The MGM/Polyvinylidene composites exhibit excellent dielectric properties (dielectric constant is 2360, dielectric loss is 2.0) near the percolation threshold at 1kHz which are better than that of most carbon/polymer composites. The excellent dielectric properties originate from the poor conductive MnO2 layers which not only ensure good dispersion of graphene nanosheets in the Polyvinylidene fluoride but also act as inter-particle barriers to prevent direct contact of the graphene nanosheets.