Electrophoretic Deposition of Organic - Inorganic Composites for Biomedical Applications

2012 ◽  
Vol 706-709 ◽  
pp. 617-622
Author(s):  
Rong Ma ◽  
Igor Zhitomirsky

Electrophoretic deposition method has been developed for the fabrication of organic-inorganic composite films, containing bioglass and hydroxyapatite in a hyaluronic acid matrix. The film composition and deposition yield were varied by variation of the electrochemical bath composition and deposition time. The films were studied by scanning electron microscopy, thermogravimetric analysis and X-ray diffraction methods. The deposition method offers the advantages of room temperature processing and allows the fabrication of composite films for biomedical applications.

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Bizuneh Workie ◽  
Brian E. McCandless ◽  
Zewdu Gebeyehu

We have studied electrophoretic deposition of AlN from its suspension in acetylacetone with I2as an additive. AlN powder with particle size <10 μm is dispersed to produce a positive charge and deposited on the cathode by applying fields greater than 10 V/cm between the electrodes. X-ray diffraction and FTIR studies indicate that the AlN before and after deposition has the same composition and structure. An increase in the amount of AlN in the suspension, the deposition potential, and the deposition time results in a linear increase in the weight of the AlN deposited. Electrophoretic deposition from 10 g/L AlN suspension shows an initial increase in the weight of AlN deposited with the concentration of I2, and the weight of AlN decreases after reaching a maximum at 0.20 g/L I2.


2007 ◽  
Vol 72 (3) ◽  
pp. 275-287 ◽  
Author(s):  
Marija Djosic ◽  
Vesna Miskovic-Stankovic ◽  
Vladimir Srdic

An aqueous boehmite sol was prepared by the peptization of Al(OH)3. The electrophoretic deposition of boehmite coatings on titanium from the aqueous sol was performed at a constant voltage (from 1.0 to 10 V) and for a constant deposition time (from 10 to 30 min). Increasing the applied voltage and deposition time increased the mass of the boehmite coating. It was shown that boehmite coatings of maximum thickness, low porosity and good adhesion can be formed at lower deposition voltages and longer deposition times. The boehmite powder, obtained by drying the prepared aqueous sol, and the boehmite coatings were thermally treated at 1000 ?C and 1300 ?C with a holding period of 1 h at the maximum temperature. X-Ray diffraction analysis of the thermally treated samples confirmed the existence of ?-Al2O3 and ????Al2O3 phases, respectively, while scanning electron microscopy revealed the graininess of the structure of the ?-Al2O3 coatings treated at 1300 ?C, indicating a significantly lower sintering temperature of the boehmite coating obtained by electrophoretic deposition.


2010 ◽  
Vol 25 (4) ◽  
pp. 658-664 ◽  
Author(s):  
Chang-An Wang ◽  
Keyu Chen ◽  
Yong Huang ◽  
Huirong Le

Layer-structured polypyrrole/montmorillonite (PPy/MMT) naoncomposite films were synthesized by the electrodeposition method. The fabricated free-standing films consist of about 0∼2 wt% Na+-montmorillonite (NMMT). The thickness of films could be controlled by deposition time. X-ray diffraction (XRD) and scanning electron microscope (SEM) were used to observe the microstructure of the films. After MMT was introduced into the PPy matrix, the interspace between PPy chains decreased, according to the XRD results. The layered structure of the films was observed from the SEM images. Tensile and nanoindentation test results showed that the mechanical properties of the composite films were improved at low clay loading. The electrical conductivity of the films with 1.2 wt% MMT loading was increased from 3.6 to 51 S/cm, probably because of the restricted growth of PPy chains in the interspace of MMT layers.


2018 ◽  
Vol 27 (1) ◽  
pp. 11-19 ◽  
Author(s):  
Emaad T Bakir Al-Tikrity ◽  
Ibrahim F Waheed ◽  
Sabah M Ali

This work reports the synthesis and characterisation of reduced graphene-1,3,4-oxadiazole-2-thiol (rGS) as a novel nanocompound derivative for graphene. The preparation was performed through a series of reactions starting from graphene oxide, followed by incorporation of different proportions of this nanocompound with poly(vinyl alcohol) (PVA), via non-covalent bonding, to afford the rGS/PVA polymer composites. The pure rGS compound, rGS/PVA composite films and pure PVA film were characterised by different techniques including infrared (Fourier transform infrared) spectroscopy, scanning electron microscopy and powder x-ray diffraction. The electrical properties of the composite films, involving dielectric constant, permittivity ( ε′), imaginary permittivity ( ε″), conductivity (σAC) and loss factor tan δ, were investigated. The measurements were performed at frequencies of (5kHz to 0.5 MHz) at room temperature. At low frequency, the dielectric permittivity ( ε′) and imaginary permittivity ( ε″) attained higher values in all cases, although with increasing frequency these values diminished rapidly. It was also found that the alternating current conductivity of the composites increased with increasing frequency.


2005 ◽  
Vol 04 (03) ◽  
pp. 409-418 ◽  
Author(s):  
XIN PANG ◽  
IGOR ZHITOMIRSKY

New method has been developed for the fabrication of nanocomposite hydroxyapatite (HA)-chitosan coatings. The method is based on the electrophoretic deposition (EPD) of HA nanoparticles prepared by a chemical precipitation technique, and electrochemical deposition of chitosan macromolecules. The deposit composition can be varied by the variation of HA concentration in chitosan solutions. X-ray studies revealed preferred orientation of HA nanoparticles in the nanocomposites with c-axis parallel to the coating surface. Nanocomposite coatings were obtained on Ti and Pt foils, Ti wires and gauzes. Deposition yield can be controlled by the variation of the deposition time. Coatings of various thicknesses in the range of up to 50 μm were obtained. The method enables the formation of dense, adherent and uniform deposits on substrates of complex shape. The obtained coatings provide corrosion protection of Ti and can be utilized for the fabrication of advanced biomedical implants.


2008 ◽  
Vol 388 ◽  
pp. 205-208
Author(s):  
Muneyasu Suzuki ◽  
Tetsuo Uchikoshi ◽  
Yuji Noguchi ◽  
Masaru Miyayama

Magnetic-field-assisted electrophoretic deposition (B-assisted EPD) method has been applied for synthesizing a(b)-axis-oriented Bi5FeTi3O15 ceramics, and the effects of the B-assisted EPD on grain orientation and microstructures have been investigated. The sintering at 1100oC of the green compact obtained by the B-assisted EPD led to dense ceramics with a high relative sintered density of 98%. X-ray diffraction analysis shows that the a(b)-axis-orientation degree of the grain oriented ceramics evaluated by the Lotgering method was 45 %.


2008 ◽  
Vol 368-372 ◽  
pp. 1825-1827
Author(s):  
Wei Lin ◽  
Chang An Wang ◽  
Yong Huang

Electrophoretic deposition (EPD) has been widely studied in preparing clay-modified electrodes (CMEs) and in assembly of nano-laminated composite that mimics nacre. In this paper, the hydrothermal intercalation and EPD were combined to prepare CMEs with a uniform and continuous polymer/clay composite film of brick-and-mortar nano-laminated structure. X-ray diffraction, scanning electronic microscopy and thermal gravimetric analysis were employed to characterize the structure and composition of the films. Stability of aqueous suspension, temperature for hydrothermal intercalation and deposition time, etc. were systematically studied and discussed.


2008 ◽  
Vol 23 (6) ◽  
pp. 1706-1712 ◽  
Author(s):  
Chang-An Wang ◽  
Bin Long ◽  
Wei Lin ◽  
Yong Huang ◽  
Jialin Sun

Poly(amic acid) (PAA)–clay nacrelike composite films have been prepared by electrophoretic deposition of an emulsion of PAA, which was synthesized from pyromellitic dianhydride and 4,4′-dianminodiphenyl ether (ODA), containing various loadings of ODA-modified montmorillonite (MMT). The layered silicate was intercalated through reacting with PAA, and the ordered layered assembly of the PAA–MMT composite films was successfully accomplished, as conformed by Fourier transform infrared analysis and x-ray diffraction. The structural characterization of the films was supported by scanning electron microscopy, which displayed an ordered layered structure. The thermogravimetric analysis showed the content of the ODA-modified clay in PAA–MMT composite films that changed from 14.3 to 32.1 wt% and the improved thermal properties of the composite films. The mechanical properties of the composites were measured by tensile test. It was found that the modulus and strength of the composite films were greatly improved compared to those of the pure polymer film. An increment of about 155% in the modulus and 40% in the tensile strength were obtained from the composite films.


Fibers ◽  
2019 ◽  
Vol 7 (6) ◽  
pp. 57 ◽  
Author(s):  
Rohan S. Dassanayake ◽  
Poorna T. Wansapura ◽  
Phat Tran ◽  
Abdul Hamood ◽  
Noureddine Abidi

A cellulose-cadmium (Cd)-tellurium (TE) quantum dots (QDs) composite film was successfully synthesized by incorporating CdTe QDs onto a cellulose matrix derived from waste cotton linters. Cellulose-CdTe QDs composite film was characterized by field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray (EDX) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), and X-ray diffraction (XRD). The antibacterial activity of the prepared composite film was investigated using the multidrug-resistance (MTR) Staphylococcus aureus bacteria. In vitro antibacterial assays demonstrated that CdTe QDs composite film can efficiently inhibit biofilm formation. Our results showed that the cellulose-CdTe QDs composite film is a promising candidate for biomedical applications including wound dressing, medical instruments, burn treatments, implants, and other biotechnology fields.


2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
Bong Ju Lee ◽  
Jin Jeong

Al-doped CdO thin films were prepared by radio frequency magnetron sputtering at different deposition time and substrate temperature. X-ray diffraction showed that the changes in the intensities of the (200), (220), and (311) planes followed a similar trend with increase in deposition time. The surface of the thin film was examined by scanning electron microscopy. Grain sizes of Al-doped CdO thin films increased significantly with increasing deposition time. The film thicknesses were 0.09, 0.12, 0.20, and 0.225 μm for the deposition times of 1, 2, 3, and 4 h, respectively. The photoluminescence spectra of the Al-doped CdO thin films were measured at room temperature. The photoluminescence wavelength changed in the sequence, green, blue, green, and blue, with increasing deposition time, which indicates that blue light emitting films can be fabricated by adjusting the processing parameters.


Sign in / Sign up

Export Citation Format

Share Document