Piezoelectric Poly Vinylidene Fluoride-trifluoroethylene Research Articles

Flexible nano-vibration energy harvester using three-phase polymer composites

In this article, we present the new three-phase piezo-polymer composite energy harvester, scavenging the electrical energy form ambient vibration. Nano magnesium oxide (MgO) and piezoelectric nano zinc oxide (ZnO) fillers in piezoelectric PolyVinyliDene fluoride-TriFluoroEthylene P(VDF-TrFE) polymer chain to form the hybrid composite material. P(VDF-TrFE)/ZnO with 2 wt%, 4 wt%, 6 wt% of MgO composite and pure P(VDF-TrFE) thin film nanoparticle allocation, crystalline structure, dielectric behavior and frequency analysis results, electrical output are characterized scanning electron microscopy (SEM), X-Ray diffraction (XRD, Impedance analyzer, Laser Doppler vibrometer and vibration shaker setup, respectively. The dielectric constant and crystalline structures improved by increasing the weight percentage of MgO nanofillers. The cantilever model Flexible Vibration Energy Harvester (FVEH) under the resonance frequency (56 Hz), it produces the maximum harvester output AC voltage (1.89 V) in size of 10 mm × 10 mm active piezoelectric layer. The resonance frequency generated through base excitation at a newly designed vibration shaker. The generated voltage used for microelectronics devices, medical application MEMS sensors.

Enhanced noradrenergic axon regeneration into schwann cell-filled PVDF-TrFE conduits after complete spinal cord transection.

Schwann cell (SC) transplantation has been utilized for spinal cord repair and demonstrated to be a promising therapeutic strategy. In this study, we investigated the feasibility of combining SC transplantation with novel conduits to bridge the completely transected adult rat spinal cord. This is the first and initial study to evaluate the potential of using a fibrous piezoelectric polyvinylidene fluoride trifluoroethylene (PVDF-TrFE) conduit with SCs for spinal cord repair. PVDF-TrFE has been shown to enhance neurite growth in vitro and peripheral nerve repair in vivo. In this study, SCs adhered and proliferated when seeded onto PVDF-TrFE scaffolds in vitro. SCs and PVDF-TrFE conduits, consisting of random or aligned fibrous inner walls, were transplanted into transected rat spinal cords for 3 weeks to examine early repair. Glial fibrillary acidic protein (GFAP)+ astrocyte processes and GFP (green fluorescent protein)-SCs were interdigitated at both rostral and caudal spinal cord/SC transplant interfaces in both types of conduits, indicative of permissivity to axon growth. More noradrenergic/DβH+ (dopamine-beta-hydroxylase) brainstem axons regenerated across the transplant when greater numbers of GFAP+ astrocyte processes were present. Aligned conduits promoted extension of DβH+ axons and GFAP+ processes farther into the transplant than random conduits. Sensory CGRP+ (calcitonin gene-related peptide) axons were present at the caudal interface. Blood vessels formed throughout the transplant in both conduits. This study demonstrates that PVDF-TrFE conduits harboring SCs are promising for spinal cord repair and deserve further investigation. Biotechnol. Bioeng. 2017;114: 444-456. © 2016 Wiley Periodicals, Inc.

Electro‐active polymer transduction for distributed netted sensing

The Naval Undersea Warfare Center in Newport, RI is developing an electro‐active polymer‐based sensing node for use in a persistent distributed underwater surveillance system. Persistence demands extreme energy conservation measures. The node will resemble a jellyfish in form, complete with tentacles housing a volumetric array of light‐weight piezoelectric polyvinylidene fluoride trifluoroethylene (PVDF‐TrFE) copolymer cylindrical hydrophones designed for an ultra‐low power acoustic receiver. Each cylinder has conductive silver electrodes on the inside and outside surfaces, a length of 2.5 cm, an outside diameter of 11 mm, a 1 mm wall thickness, and a mass less than 2 g. Operating in the hydrostatic mode, the hydrophone sensitivity is typically ‐195 dB//1 V/μPa and is stable with both hydrostatic pressure (50 to 1000 psi) and temperature (‐1 to 35°C). [Work supported by the Office of Naval Research.]