Investigation of Poly(vinyl pyrrolidone) in methanol by dynamic light scattering and viscosity techniques

e-Polymers ◽  
2007 ◽  
Vol 7 (1) ◽  
Author(s):  
Adel Aschi ◽  
Mohamed Mondher Jebari ◽  
Abdelhafidh Gharbi
Keyword(s):  
Light Scattering ◽  
Dynamic Light Scattering ◽  
Molecular Mass ◽  
Vinyl Pyrrolidone ◽  
Least Squares Regression ◽  
Particle Structure ◽  
Crossover Point ◽  
Molecular Weights ◽  
Poly Vinyl Pyrrolidone ◽  
Methanol System

AbstractThe behavior of poly(vinyl pyrrolidone) (PVP) in methanol was examined using several independent methods. The hydrodynamic radius (Rh) of individual samples, over a range of molecular weights (10,000-360,000), was determined using dynamic light scattering (DLS) measurements. Dynamic Light Scattering (DLS) techniques directly probe such dynamics by monitoring and analyzing the pattern of fluctuations of the light scattered from polymer molecules. Some viscosity measurements were also performed to complete the DLS measurements and to provide more information on the particle structure. The results obtained with PVP-methanol system showed that plotting the variation of intrinsic viscosity versus the logarithm of the molecular mass of this polymer, we observe one crossover point. This crossover point appears when we reach the Θ-solvent behavior and delimit two molecular mass regions. The second order least-squares regression was used as an approach and was in excellent agreement with viscometric experimental results.

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

Geofluids ◽  
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.

Light Scattering Study of Aqueous Poly(Vinyl)pyrrolidone–Fullerene C70 Solutions

2005 ◽  
Vol 12 (1-2) ◽  
pp. 349-352 ◽  
Author(s):  
Elvira V. Tarassova ◽  
Vladimir O. Aseyev ◽  
Heikki J. Tenhu ◽  
Inga A. Baranovskaya ◽  
Stanislav I. Klenin
Keyword(s):  
Light Scattering ◽  
Vinyl Pyrrolidone ◽  
Scattering Study ◽  
Poly Vinyl Pyrrolidone

scholarly journals Experimental measurements and modeling of solvent activity and surface tension of binary mixtures of polyvinylpyrrolidone in water and ethanol

2017 ◽  
Vol 82 (4) ◽  
pp. 427-435
Author(s):  
Majid Taghizadeh ◽  
Saber Amiri
Keyword(s):  
Surface Tension ◽  
Vinyl Pyrrolidone ◽  
Polymer Mixtures ◽  
Temperature Range ◽  
Molecular Weights ◽  
Activity Measurements ◽  
Mass Fractions ◽  
Eyring Model ◽  
Poly Vinyl Pyrrolidone ◽  
Solvent Activity

In this paper, the density (?), viscosity (?) and surface tension (?) of solutions of poly(vinyl pyrrolidone) (PVP) with molecular weights of 25000 (K25) and 40000 g mol-1 (K40) in water and ethanol were measured in the temperature range 20?65?C and at various mass fractions of polymer (0.1, 0.2, 0.3 and 0.45). The solvent activity measurements were performed at 45 and 55?C. Thereafter, two thermodynamic models for predicting the solvent activity and surface tension of binary polymer mixtures (PVP in water and ethanol) were proposed. The Flory?Huggins theory and Eyring model were employed to calculate the surface tension of the solution and the solvent activity, respectively. Additionally, the proposed activity model was dependent on the density and viscosity of the solution. Afterwards, the ability of these models at various temperatures and mass fractions were investigated by comparing the results with the experimental data. The results confirmed that, in the investigated temperature range, these models have good accuracy.

scholarly journals New amphiphilic glycopolymers by click functionalization of random copolymers – application to the colloidal stabilisation of polymer nanoparticles and their interaction with concanavalin A lectin

2010 ◽  
Vol 6 ◽  
Author(s):  
Otman Otman ◽  
Paul Boullanger ◽  
Eric Drockenmuller ◽  
Thierry Hamaide
Keyword(s):  
Light Scattering ◽  
Molecular Recognition ◽  
Dynamic Light Scattering ◽  
Concanavalin A ◽  
Triblock Copolymer ◽  
Polymer Nanoparticles ◽  
Vinyl Pyrrolidone ◽  
Random Copolymers ◽  
Long Time ◽  
Polymer Surfactants

Glycopolymers with mannose units were readily prepared by click chemistry of an azido mannopyranoside derivative and a poly(propargyl acrylate-co-N-vinyl pyrrolidone). These glycopolymers were used as polymer surfactants, in order to obtain glycosylated polycaprolactone nanoparticles. Optimum stabilization for long time storage was achieved by using a mixture of glycopolymers and the non-ionic triblock copolymer Pluronic® F-68. The mannose moieties are accessible at the surface of nanoparticles and available for molecular recognition by concanavalin A lectin. Interaction of mannose units with the lectin were evaluated by measuring the changes in nanoparticles size by dynamic light scattering in dilute media.

Light scattering andin vitro biocompatibility studies of poly (vinyl pyrrolidone) derivatives with amino-acid-dependent groups

2002 ◽  
Vol 63 (6) ◽  
pp. 830-837 ◽  
Author(s):  
Stavroula Baritaki ◽  
George N. Tzanakakis ◽  
John Alifragis ◽  
Alexis Zafiropoulos ◽  
Ravshan I. Tashmukhamedov ◽  
...  
Keyword(s):  
Amino Acid ◽  
Light Scattering ◽  
Vinyl Pyrrolidone ◽  
Poly Vinyl Pyrrolidone

scholarly journals Influence of water-soluble nonionic polymers adsorption on colloidal properties of nanosilica dispersions

2019 ◽  
Vol 7 (1) ◽  
pp. 57-73
Author(s):  
Olena V. Goncharuk ◽  
Maria L. Malysheva ◽  
Konrad Terpilowski ◽  
Salvador Pérez Huertas ◽  
Volodymyr M. Gun’ko
Keyword(s):  
Water Soluble ◽  
Vinyl Pyrrolidone ◽  
Poly Vinyl Alcohol ◽  
Aggregative Stability ◽  
Polymer Content ◽  
Molecular Weights ◽  
Adsorbed Polymer ◽  
Influence Of Water ◽  
Silica Dispersion ◽  
Poly Vinyl Pyrrolidone

The relationships between the adsorption of poly(vinyl alcohol) (PVA), poly(ethylene oxide) (PEO), and poly(vinyl pyrrolidone) (PVP) of various molecular weights onto nanosilica and the stability and rheological properties of the aqueous dispersions were analyzed. The adsorption isotherms for the polymers correspond to the Langmuir-type isotherms. The adsorption maximum slightly increases with increasing molecular weight of the polymers. The sedimentation and aggregative stability of the silica dispersion decreased at a low amount of an adsorbed polymer (less than a monolayer). At this polymer content, a significant increase in the viscosity of dispersions is observed due to the formation of polymeric bridges between silica nanoparticles from neighboring aggregates of them. If the amount of adsorbed polymer exceeds the monolayer then the stabilizing effect is observed due to the steric factor preventing the bridge formation and the viscosity of dispersion decreases slightly compared with systems with a low polymer content.

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