Structural Optimization of Vanadium Oxides Prepared via a Polymer Assisted Deposition

Vanadium dioxide film, to be used as a thermochromic material for smart glazing, were prepared and fabricated on glass substrate via a polymer assisted deposition (PAD). Poly (vinyl pyrrolidone) (PVP) and poly (vinyl alcohol) (PVOH) were used as the film former to control the viscosity of precursor solution and interact with vanadium ions. The structural characteristic of vanadium oxides films was optimized in this work using Taguchi's experimental design. The optimization was performed by considering the effect of annealing temperature, annealing time and heating rates on film thickness and XRD patterns of the prepared film. The results from XRD patterns indicated that the optimum conditions corresponding to the formation of vanadium dioxide (VO2), regardless of the polymer type, is that by using the annealing time and temperature of 6 h and 450 °C, respectively.

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Effect of Polyvinyl Pyrrolidone Dosage on Barium Ferrite Fibers via Electrospinning

Materials Science Forum ◽

10.4028/www.scientific.net/msf.848.333 ◽

2016 ◽

Vol 848 ◽

pp. 333-338

Author(s):

Yue Guang Chen ◽

Gui Fang Liu ◽

Shi Jiao Wang

Keyword(s):

Barium Ferrite ◽

Raw Materials ◽

Precursor Solution ◽

Vinyl Pyrrolidone ◽

Dimethyl Formamide ◽

X Ray Diffraction ◽

Sem Images ◽

Vibration Sample Magnetometer ◽

Poly Vinyl Pyrrolidone ◽

Xrd Patterns

Barium ferrite micro/nanofibers were successfully prepared via the electrospinning by using dimethyl formamide (DMF) as the solvent, poly vinyl pyrrolidone (PVP) as the spinning auxiliaries and iron nitrate and barium nitrate as raw materials. The effect of poly vinyl pyrrolidone on the structure, morphology, magnetic and microwave absorbing properties were investigated by scanning electron microscope (SEM), X-ray diffraction analysis (XRD), vibration sample magnetometer (VSM) and vector network analyzer (VNA). XRD patterns of the samples confirmed that when the additive content of PVP was up to 10%, (wt%) pure barium ferrite fibers formed under the condition of the same heat treatment. Also, the FE-SEM images showed that the morphology of the fibers improved with the increase of PVP content. Moreover, the VSM results demonstrated that the saturation magnetization can reach 54.7 emu/g when the PVP dosage is 14% (wt%) in the precursor solution.

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Poly(vinyl alcohol) and poly(vinyl pyrrolidone) blended films for local nitric oxide release

Biomaterials ◽

10.1016/j.biomaterials.2003.10.035 ◽

2004 ◽

Vol 25 (17) ◽

pp. 3773-3782 ◽

Cited By ~ 109

Author(s):

Amedea Barozzi Seabra ◽

Marcelo Ganzarolli de Oliveira

Keyword(s):

Nitric Oxide ◽

Vinyl Alcohol ◽

Vinyl Pyrrolidone ◽

Poly Vinyl Alcohol ◽

Nitric Oxide Release ◽

Poly Vinyl Pyrrolidone

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PREPARATION AND CHARACTERIZATION OF POLY (VINYL ALCOHOL)–POLY (VINYL PYRROLIDONE) MUCOADHESIVE BUCCAL PATCHES FOR DELIVERY OF LIDOCAINE HCL

International Journal of Applied Pharmaceutics ◽

10.22159/ijap.2018v10i1.23208 ◽

2018 ◽

Vol 10 (1) ◽

pp. 115 ◽

Cited By ~ 5

Author(s):

Napaphak Jaipakdee ◽

Thaned Pongjanyakul ◽

Ekapol Limpongsa

Keyword(s):

Vinyl Alcohol ◽

Vinyl Pyrrolidone ◽

Poly Vinyl Alcohol ◽

Scanning Calorimetry ◽

X Ray ◽

Casting Technique ◽

In Vitro Permeation ◽

Lidocaine Hcl ◽

Poly Vinyl Pyrrolidone

Objective: The objectives of this study were to prepare and characterize a buccal mucoadhesive patch using poly (vinyl alcohol) (PVA), poly (vinyl pyrrolidone) (PVP) as a mucoadhesive matrix, Eudragit S100 as a backing layer, and lidocaine HCl as a model drug.Methods: Lidocaine HCl buccal patches were prepared using double casting technique. Molecular interactions in the polymer matrices were studied using attenuated total reflectance-fourier transform infrared spectroscopy (ATR-FTIR), differential scanning calorimetry (DSC) and X-ray diffractometry. Mechanical and mucoadhesive properties were measured using texture analyzer. In vitro permeation of lidocaine HCl from the patch was conducted using Franz diffusion cell.Results: Both of the free and lidocaine HCl patches were smooth and transparent, with good flexibility and strength. ATR-FTIR, DSC and X-ray diffractometry studies confirmed the interaction of PVA and PVP. Mechanical properties of matrices containing 60% PVP were significantly lower than those containing 20% PVP (*P<0.05). Mucoadhesive properties had a tendency to decrease with the concentration of PVP in the patch. The patch containing 60% PVP had significantly lower muco-adhesiveness than those containing 20% PVP (*P<0.05). In vitro permeation revealed that the pattern of lidocaine HCl permeation started with an initial fast permeation, followed by a slower permeation rate. The initial permeation fluxes follow the zero-order model of which rate was not affected by the PVP concentrations in the PVA/PVP matrix.Conclusion: Mucoadhesive buccal patches fabricated with PVA/PVP were successfully prepared. Incorporation of PVP in PVA/PVP matrix affected the strength of polymeric matrix and mucoadhesive property of patches.

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Testing the Performance of Various Polymeric Antiscalants for Mitigation of Sb-Rich Precipitates Mimicking Stibnite-Based Geothermal Deposits

Geofluids ◽

10.1155/2020/8867084 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10

Author(s):

Celal Çiftçi ◽

Emre Karaburun ◽

Serhat Tonkul ◽

Alper Baba ◽

Mustafa M. Demir ◽

...

Keyword(s):

Power Plants ◽

Vinyl Pyrrolidone ◽

Poly Vinyl Alcohol ◽

Poly Ethylene Glycol ◽

Molecular Weights ◽

Geothermal Fields ◽

The World ◽

Testing Potential ◽

Poly Ethylene ◽

Poly Vinyl Pyrrolidone

Scaling is frequently observed in geothermal fields and reduces the energy harvesting of power plants. Recently, Sb-rich deposits have developed in many fields around the world. Various polymeric macromolecules have been used as antiscalants to mitigate the formation of scale. Testing potential commercial antiscalants in field conditions is a tedious and costly process. The artificial synthesis of geothermal deposits in the lab is a more practical and economical way to test the performance of antiscalants. This study obtained a Sb-rich deposit by refluxing SbCl3 and Na2S·3H2O in 18 h. The product was found to be a mixture of Sb2O3 and Sb2S3. We examined the performance of antiscalants such as poly(ethylene glycol), poly(vinyl pyrrolidone), Gelatin, and poly(vinyl alcohol) of various molecular weights at 5 to 100 ppm. The formation of Sb2S3 is suppressed in the presence of the polymeric antiscalants. The dosage was found to be critical for the solubilization of Sb-rich deposits. Gelatin of 5 ppm showed the highest performance under the conditions employed in this study. While low dosages improve the concentration of [Sb3+], high dosages are required to increase the solubility of [S2-]. Moreover, the amount of deposit is reduced by 12.4% compared to the reference (in the absence of any polymeric molecules). Thus, comparatively, Gelatin shows the most promising performance among the molecules employed.

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