INFLUENCE OF THE SUBSTRATE ON THE CRYSTALLINE PHASE AND MORPHOLOGY OF POLY (VINYLIDENE FLUORIDE) (PVDF) THIN FILM

2016 ◽  
Vol 23 (03) ◽  
pp. 1650005 ◽  
Author(s):  
IBTISAM YAHYA ABDULLAH ◽  
MUHAMMAD YAHAYA ◽  
MOHAMMAD HAFIZUDDIN HJ JUMALI ◽  
HAIDER MOHAMMED SHANSHOOL
Keyword(s):  
Thin Film ◽  
Indium Tin Oxide ◽  
Crystalline Phase ◽  
Vinylidene Fluoride ◽  
Average Diameter ◽  
X Ray Diffraction ◽  
X Ray ◽  
Coated Glass ◽  
Poly Vinylidene Fluoride ◽  
Hexamethyl Phosphoramide

The effect of substrate on the crystalline phase and morphology of the poly (vinylidene fluoride) (PVDF) thin film has been investigated. The solution of PVDF/Hexamethyl phosphoramide (HMPA) was deposited on four different substrates, namely, silicon (Si), glass (SiO2), indium tin oxide (ITO) coated glass and silver (Ag) coated glass respectively by using the spin coating technique. The crystalline structure was investigated using X-ray diffraction (XRD) and Fourier transform infrared (FTIR) techniques. The morphology was determined using scanning electron microscopy (SEM). XRD demonstrated that the structure of PVDF thin films on each substrate is [Formula: see text]-phase with different orientations of the molecular chains. FTIR results confirmed XRD that the samples contain [Formula: see text]-phase. SEM shows spherulites structure, which is rough and porous, besides, the size of spherulites and the porosity are different for each sample. The size of spherulites is in average diameter range (1–6[Formula: see text][Formula: see text]m) and this range is attributed to the [Formula: see text]-phase. The nucleation process of [Formula: see text]-phase on the various substrates attributed either to the match of polymer-substrate or to the electrostatic interaction. Among the substrates used, the ITO substrate exhibited a greater tendency for [Formula: see text]-phase formation.

Stretching Induced Crystalline-Phase Transition in Energy-Conversion Poly(Vinylidene Fluoride) (PVDF) Films

2014 ◽  
Vol 1070-1072 ◽  
pp. 589-593
Author(s):  
Fei Peng Wang ◽  
Zheng Yong Huang ◽  
Jian Li
Keyword(s):  
Phase Transition ◽  
Crystalline Phase ◽  
High Speed ◽  
Vinylidene Fluoride ◽  
X Ray Diffraction ◽  
X Ray ◽  
Β Phase ◽  
Α Phase ◽  
Poly Vinylidene Fluoride ◽  
Crystalline Phase Transition

Commercial poly (vinylidene fluoride) (PVDF) films are uniaxially stretched with varying rates at 110 °C in order to endow PVDF piezo-and pyroelectric by crystalline-phase transition from α to β during the stretching. The crystalline phases are determined by infrared spectroscopy. The β-phase content and its fraction in films increase as a result of stretching with high rates. In addition, higher stretching rates yield a slight increase of γ phase. The crystallite size is evaluated by means of X-ray diffraction. It is found that the β-phase crystallites become smaller with fast stretching, whereas the α-phase crystallites are cracked and disappear at high-speed stretching of 2.5 /min.

An approach to durable poly(vinylidene fluoride) thin film loudspeaker

2003 ◽  
Vol 18 (12) ◽  
pp. 2904-2911 ◽  
Author(s):  
C.S. Lee ◽  
J.Y. Kim ◽  
D.E. Lee ◽  
J. Joo ◽  
S. Han ◽  
...  
Keyword(s):  
Thin Film ◽  
Indium Tin Oxide ◽  
Photoelectron Spectroscopy ◽  
Vinylidene Fluoride ◽  
X Ray ◽  
Force Microscopy ◽  
Low Surface Energy ◽  
Oxide Electrodes ◽  
Atomic Force ◽  
Poly Vinylidene Fluoride

The piezoelectric poly(vinylidene fluoride) (PVDF) surface possessing low surface energy was modified by the ion-assisted-reaction (IAR) method for the application of thin film speaker. The IAR-treated hydrophilic PVDF surface was investigated using atomic force microscopy and x-ray photoelectron spectroscopy. The adhesion strength between various types of electrodes and the film was dramatically improved due to the hydrophilic functional groups, such as –C–O–, –(C=O)–, –(C=O)–O–, and so forth. A durable loudspeaker film was fabricated by enhancing the adhesion between the screen-printed poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS) and the modified PVDF films. The PVDF speaker film with the PEDOT/PSS electrode showed higher durability, flatter sound pressure level characteristics, and easier processability compared to metals or indium tin oxide electrodes.

Simulations of High-Strain Electrostrictive Chlorinated Terpolymers

2003 ◽  
Vol 785 ◽  
Author(s):  
George J. Kavarnos ◽  
Thomas Ramotowski
Keyword(s):  
Vinylidene Fluoride ◽  
High Strain ◽  
Polymer Chains ◽  
X Ray Diffraction ◽  
X Ray ◽  
Lamellar Structures ◽  
Annealing Conditions ◽  
Poly Vinylidene Fluoride ◽  
Electromechanical Responses ◽  
Kinetics Of

ABSTRACTChlorinated poly(vinylidene fluoride/trifluoroethylene) terpolymers are remarkable examples of high strain electrostrictive materials. These polymers are synthesized by copolymerizing vinylidene fluoride and trifluoroethylene with small levels of a third chlorinated monomer. The electromechanical responses of these materials are believed to originate from the chlorine atom, which, by its presence in the polymer chains and by virtue of its large van der Waals radius, destroys the long-range crystalline polar macro-domains and transforms the polymer from a normal to a high-strain relaxor ferroelectric. To exploit the strain properties of the terpolymer, it is desirable to understand the structural implications resulting from the presence of the chlorinated monomer. To this end, computations have been performed on model superlattices of terpolymers using quantum-mechanical based force fields. The focus has been on determining the energetics and kinetics of crystallization of the various polymorphs that have been identified by x-ray diffraction and fourier transform infrared spectroscopy. The chlorinated monomer is shown to act as a defect that can be incorporated into the lamellar structures of annealed terpolymer without a high cost in energy. The degree of incorporation of the chlorinated monomer into the crystal lattice is controlled by annealing conditions and ultimately determines the ferroelectric behavior of the terpolymers.

Growth and Characterisation of Ag2S Films on ZnS/Indium-Tin-Oxide Coated Glass

2013 ◽  
Vol 721 ◽  
pp. 33-36 ◽  
Author(s):  
Hong Cheng Pan ◽  
Xue Peng Li ◽  
Wei Hong Liu ◽  
Yan Bin Ren
Keyword(s):  
Tin Oxide ◽  
Indium Tin Oxide ◽  
Phosphate Buffer Solution ◽  
Deposition Method ◽  
X Ray Diffraction ◽  
Buffer Solution ◽  
Solution Ph ◽  
X Ray ◽  
Coated Glass ◽  
Glass Substrates

ZnS thin films were deposited on indium–tin-oxide (ITO) coated glass substrates by a chemical bath deposition method. Then the ZnS/ITO slides were immersed in the solution containing 6 mM phosphate buffer solution (pH 7.4), sodium polyacrylate (0.01% w/w), and 0.24 mM AgNO3 at 37°C for 3 h to growth Ag2S films on the surface of ZnS/ITO slides. The absorption band of Ag2S/ZnS/ITO slide displays a considerably blue-shifted. The X-ray diffraction analysis demonstrated the presence of acanthite Ag2S on the surface of ZnS/ITO slides, which is consistent with the cyclic voltammetic data.

Structures and Physical Properties of Multi-Walled Carbon Nanotube-Filled PVDF Thermoplastic Composites

2007 ◽  
Vol 124-126 ◽  
pp. 1117-1120 ◽  
Author(s):  
Dong Wook Chae ◽  
Young Wan Nam ◽  
Seung Sangh Wang ◽  
S.M. Hong
Keyword(s):  
Carbon Nanotube ◽  
Vinylidene Fluoride ◽  
Thermoplastic Composites ◽  
Wide Angle ◽  
X Ray Diffraction ◽  
X Ray ◽  
Loading Level ◽  
Multi Walled Carbon Nanotube ◽  
Poly Vinylidene Fluoride ◽  
Internal Mixer

Poly(vinylidene fluoride) (PVDF) / multi-walled carbon nanotube (MWNT) thermoplastic composites was melt compounded in an internal mixer. The percolation level for this system in electrical conductivity clearly occured between 2 and 2.5 wt%. PVDF/MWNT thermoplastic composites exhibited an increased crystallization temperature with the loading level, at 10 wt% loading by ca. 6. In addition, they presented a shoulder posterior to the main melting peak and an increased endpoint of the peak. In the Wide Angle X-ray Diffraction (WAXD) patterns, the incorporation of MWNT produced a larger shoulder at 2θ =20.7° with increasing the loading level, corresponding to the β-form crystal of PVDF.

scholarly journals Influence of molecular weight on dielectric properties and piezoelectric constant of poly(vinylidene fluoride) membranes obtained by electrospinning

Polimery ◽  
2021 ◽  
Vol 66 (10) ◽  
pp. 532
Author(s):  
Aminatul Sobirah Zahari ◽  
Muhammad Hafiz Mazwir ◽  
Izan Izwan Misnon
Keyword(s):  
Molecular Weight ◽  
Dielectric Properties ◽  
Vinylidene Fluoride ◽  
Electrochemical Impedance ◽  
Piezoelectric Constant ◽  
Phase Content ◽  
X Ray Diffraction ◽  
X Ray ◽  
Β Phase ◽  
Poly Vinylidene Fluoride

A significant influence of the molecular weight on the dielectric properties and piezoelectric constant of poly(vinylidene fluoride) (PVDF) membranes obtained by electrospinning was demonstrated. Electrochemical impedance spectroscopy and d33 meter were used to evaluate dielectric properties and piezoelectric constant respectively. The presence of the β-phase was determined by Fourier transform infrared spectroscopy (FTIR) and X-Ray diffraction (XRD). The membranes with the lowest molecular weight (180,000 g/mol) possessed the best dielectric properties. They also had the highest piezoelectric constant (21 pC/N) and dielectric constant (2.9 at 50 Hz) as well as the highest β-phase content (80.25%).

Effect of Thermal Treatment on the Physical Properties of Electrospun PVDF Membrane

2012 ◽  
Vol 591-593 ◽  
pp. 1113-1116
Author(s):  
Si Chen Cheng ◽  
Yin Zheng Liang ◽  
Yi Ping Qiu
Keyword(s):  
Thermal Treatment ◽  
Tensile Property ◽  
Tensile Testing ◽  
Vinylidene Fluoride ◽  
X Ray Diffraction ◽  
Electrospinning Technique ◽  
Pvdf Membrane ◽  
X Ray ◽  
Before And After ◽  
Poly Vinylidene Fluoride

The electrospinning technique was used to produce poly (vinylidene fluoride) (PVDF) membrane. Thermal treatment was introduced to improve the mechanical property and dimensional stability. In this paper, the PVDF membranes before and after thermal treatment were characterized by Scanning electron microscope (SEM), differential scanning calorimeter (DSC) and wide angle X-ray diffraction (WAXD), tensile testing. The crystallinity, tensile property, as well as melting temperature changed with the treated temperature. The results hows that thermal treatment could notably increase the tensile property of electrospun PVDF membrane and 160°C is a proper temperature for thermal treating

Electrodeposition of lithium phthalocyanine thin films: Part I. Structure and morphology

1999 ◽  
Vol 14 (5) ◽  
pp. 2162-2172 ◽  
Author(s):  
M. Brinkmann ◽  
S. Graff ◽  
C. Chaumont ◽  
J-J. André
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Indium Tin Oxide ◽  
Film Growth ◽  
Oxidation Potential ◽  
Thin Film Growth ◽  
Ex Situ ◽  
X Ray Diffraction ◽  
X Ray ◽  
Film Synthesis

A new thin film synthesis route based on the electrochemical oxidation of PcLi2 and deposition of lithium phthalocyanine (PcLi) onto indium tin oxide (ITO) substrate is demonstrated. The effects on the thin film morphology of various parameters such as the electrolysis time, the nature of the solvent, and the oxidation potential are investigated. The thin film growth is studied via x-ray diffraction, potential step experiments, and ex situ scanning electron microscopy. Various morphologies of the x-form thin films are observed for different electrolysis times and solvents. Thin films grown in acetonitrile of thickness above 1 μm consist in unidirectionally oriented needle-shaped crystallites.

The Evolution of Activation Field with Temperature in Ferroelectric Copolymer of Vinylidene Fluoride and Trifluoroethylene Films

2013 ◽  
Vol 785-786 ◽  
pp. 761-766
Author(s):  
Lin Jiang ◽  
Xiang Jian Meng ◽  
X. L. Zhao ◽  
B. B. Tian ◽  
B. L. Liu ◽  
...  
Keyword(s):  
Thin Film ◽  
Glass Transition ◽  
Vinylidene Fluoride ◽  
Ferroelectric Thin Film ◽  
Transition Process ◽  
The Other ◽  
Polarization Reversal ◽  
X Ray Diffraction ◽  
X Ray ◽  
Polyimide Substrate

Vinylidene fluoride and trifluoroethylene [P(VDF-TrFE)] ferroelectric thin film was spin-coated on Au-coated polyimide substrate and its polarization reversal was investigated by analyzing the evolution of activation field (α) with temperature. Although α is nearly a constant between 300 and 330 K, it increases linearly when temperature rates between 200 and 230 K, and between 230 and 300 K. On the other hand, the intensity of X-ray diffraction for P(VDF-TrFE) films from 200 to 330 K indicates that glass-transition process plays a significant role in both the microstructure and the polarization reversal of P(VDF-TrFE) copolymer.

Micro-Structure and Electrical Properties of Nanocrystalline Pt Thin Film Prepared By R.F. Sputtering

1992 ◽  
Vol 286 ◽  
Author(s):  
Xiangyang Mei ◽  
Mingde Tao ◽  
Hui Tan ◽  
Ying Han ◽  
Wei Tao
Keyword(s):  
Thin Film ◽  
Annealing Temperature ◽  
Average Diameter ◽  
Prepared Film ◽  
X Ray Diffraction ◽  
Micro Structure ◽  
Temperature Coefficient Of Resistance ◽  
X Ray ◽  
Transmission Electron ◽  
Cubic Structure

ABSTRACTNanocrystalline Pt (nc-Pt) thin film was prepared by R. F. sputtering on liquid N2 cooled substrate. Transmission Electron Microscopy (TEM)analyses clearly show that the as prepared film is constructed by numerous nanometer sized particles with average diameter of about 8-9nm. The interfaces between particles can be clearly seen and the interface width is about nmm. Electron Diffraction (ED) photograph and X-ray Diffraction (XRD) spectroscopy both confirm that the nanometer sized particles in the film are ultra fine crystallites with a cubic structure. The crystallite size increases gradually with annealing temperature. The temperature coefficient of resistance (TCR) of nc-Pt film are much lower than that of polycrystalline Pt film. DC conductivity and TCR also increase gradually with the increase of annealing temperature. It is suggested that the interfaces between the nanoorystallites greatly influence the properties of nc-Pt thin film.

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