Newtonian Viscosity of Dilute, Semidilute, and Concentrated Polymer Solutions

Jamieson, A. M.; Simha, Robert

doi:10.1002/9780470600160.ch1

Cited by 6 publications

(12 citation statements)

References 143 publications

(295 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In fact, the parameter c* marks the onset of significant polymer chain overlap in solution and can be estimated by using Eqn :

c^{*} = \frac{2.5}{[η]}

where[η] is the intrinsic viscosity, defined as the increase in viscosity of a solvent through the addition of an infinitesimal amount of solute. In our case, [η] was experimentally determined by measuring the dynamic viscosity of diluted solutions and extrapolating to infinite dilution by the well‐known Huggins equation (Eqn ), where η sp is the specific viscosity of the polymer solution and K H is the Huggins constant …”

Section: Resultsmentioning

confidence: 99%

“…In fact, for the nanofibers, the T m was only partially identified as a shoulder in the thermograms. According with the literature, the dissolution step or/and the electrospinning process negatively affect the gelatin thermal stability because of the destabilization of its original chemical structure. Based on previous results carried out with acetic acid as a solvent that confirm that electrospinning process is not the main issue affecting the chemical structure of the gelatin fibers, it can be concluded that the dissolution step of gelatin is responsible for the loss of thermal properties of gelatin.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Preparation of electrospun nanofibers from solutions of different gelatin types using a benign solvent mixture composed of water/PBS/ethanol

Erencia

Cano

Tornero

et al. 2015

Polym. Adv. Technol.

View full text Add to dashboard Cite

. Preparation of electrospun nanofibers from solutions of different gelatin types using a benign solvent mixture composed of water/PBS/ethanol. Polymers for Advanced Technologies, 2016, 27, 382-392 ABSTRACTThe feasibility of using Phosphate Buffer Saline (PBS)/ethanol mixtures as a benign solvent to electrospin three types of gelatin was studied. Gelatins with different chemical properties, such as Bloom, were selected and the effect of the gelatin nature and its concentration on the electrospinnability of the dope solution and on the fiber diameter of the electrospun mats were studied. Viscosity of the gelatin solution, which follows a power law relationship with the gelatin concentration, was found to significantly influence the morphology of the mats and the fiber diameter. It was demonstrated that the PBS/ethanol solvent interacted with the gelatins as a good solvent with a Flory exponent of 0.65. In addition, the effect of the solvent composition on the fiber formation process was evaluated corroborating that the ionic strength of the medium and the PBS/ethanol ratio significantly affected the morphology and the diameter of the electrospun fibers. Chemical structure and thermal stability of the electrospun gelatin mats were characterized by Fourier Transform Infrared Spectroscopy (FTIR) and Differential Scanning Calorimetry (DSC). Finally, cytotoxicity of the electrospun mats was analyzed by the Alamar Blue assay, using human foreskin fibroblasts (BJ-5ta), resulting in a high cell viability (80-90%) regardless the type of gelatin.

show abstract

“…In fact, the parameter c* marks the onset of significant polymer chain overlap in solution and can be estimated by using Eqn :

c^{*} = \frac{2.5}{[η]}

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Preparation of electrospun nanofibers from solutions of different gelatin types using a benign solvent mixture composed of water/PBS/ethanol

Erencia

Cano

Tornero

et al. 2015

Polym. Adv. Technol.

View full text Add to dashboard Cite

show abstract

“…In addition to Brownian dynamics simulations, Pan et al [41] have carried out systematic measurements of the intrinsic viscosity of two different molecular weight samples of linear doublestranded DNA at a range of temperatures in the presence of excess salt, and examined the crossover scaling of α η and U ηR (z). Even though a number of experimental measurements of the Flory-Fox constant under good solvent conditions have been reported in the literature [43], the behaviour of Φ with varying solvent conditions and molecular weight had not been understood with any great certainty prior to this work. The results of their simulations and experimental measurements of α η are displayed in Fig.…”

Section: Thermal Crossover In Dilute Solutionsmentioning

confidence: 99%

“…There have been many attempts to understand the origin of this difference in crossover behaviour, and to predict analytically and numerically, the observed universal curves (see Ref. [43] for a recent review). Since both the hydrodynamic and viscosity radii are dynamic properties, hydrodynamic interactions play a crucial role in determining their swelling functions α H and α η .…”

Section: Thermal Crossover In Dilute Solutionsmentioning

confidence: 99%

Universal dynamics of dilute and semidilute solutions of flexible linear polymers

Prakash

2019

Current Opinion in Colloid & Interface Science

View full text Add to dashboard Cite

Experimental observations and computer simulations have recently revealed universal aspects of polymer solution behaviour that were previously unknown. This progress has been made possible due to developments in experimental methodologies and simulation techniques, and the formulation of scaling arguments that have identified the proper scaling variables with which to achieve data collapse, both for equilibrium and nonequilibrium properties. In this review, these advances in our understanding of universal polymer solution behaviour are discussed, along with a brief overview of prior experimental observations and theoretical predictions in order to provide a context for the discussion. Properties for which the existence of universality is still unclear, and those for which it has not yet been verified theoretically are highlighted, and theoretical predictions of universal behaviour that require experimental validation are pointed out.

show abstract

“…The Martin model is believed to fit the viscosity data over a wider concentration range than the Huggins model. 2 These three models all lead to [η] 0 at infinite dilution so that…”

Section: ■ Results and Discussionmentioning

confidence: 99%

Activation Thermodynamics and Concentration Scaling of the Viscosity of Unimeric and Aggregated Poloxamer EO₉₃PO₅₄EO₉₃ in Water

Quirion

2015

Macromolecules

View full text Add to dashboard Cite

The viscosity of the aqueous solutions of Poloxamer EO 93 PO 54 EO 93 (a triblock copolymer of ethylene oxide, EO, and propylene oxide, PO) was determined at concentrations ranging from 0.002 to 0.12 g•mL −1 at 0.9, 8.9, and 20.0 °C where only unimers are present, at 24.9 and 30.3 °C where the unimers are in equilibrium with aggregates and at 39.8 and 49.8 °C where only aggregates are present. The reciprocal of the intrinsic viscosity derived from Huggins, Kraemer, Martin and Phillies's models is compared to the experimentally determined overlap concentration. A simple model that accounts for intermolecular interactions provides better estimates of the experimental overlap concentration. The concentration scaling exponents of the viscosity at low and high concentrations are compared to the predictions for entangled polymer chains. It is suggested that at low temperature, the Poloxamer molecules evolve from dilute unimers to semidilute unentangled unimers. At high temperature, Poloxamer molecules evolve from dilute aggregates to semidilute entangled aggregates. Finally, the apparent molar contribution of the Poloxamer to the activation free energy and enthalpy for viscous flow can be reproduced with a mass-action model corresponding to the cooperative association of unimers to form aggregates. The model confirms that the association of the Poloxamer molecules is endothermic with a low molecularity.

show abstract

Newtonian Viscosity of Dilute, Semidilute, and Concentrated Polymer Solutions

Cited by 6 publications

References 143 publications

Preparation of electrospun nanofibers from solutions of different gelatin types using a benign solvent mixture composed of water/PBS/ethanol

Preparation of electrospun nanofibers from solutions of different gelatin types using a benign solvent mixture composed of water/PBS/ethanol

Universal dynamics of dilute and semidilute solutions of flexible linear polymers

Activation Thermodynamics and Concentration Scaling of the Viscosity of Unimeric and Aggregated Poloxamer EO₉₃PO₅₄EO₉₃ in Water

Contact Info

Product

Resources

About

Newtonian Viscosity of Dilute, Semidilute, and Concentrated Polymer Solutions

Cited by 6 publications

References 143 publications

Preparation of electrospun nanofibers from solutions of different gelatin types using a benign solvent mixture composed of water/PBS/ethanol

Preparation of electrospun nanofibers from solutions of different gelatin types using a benign solvent mixture composed of water/PBS/ethanol

Universal dynamics of dilute and semidilute solutions of flexible linear polymers

Activation Thermodynamics and Concentration Scaling of the Viscosity of Unimeric and Aggregated Poloxamer EO93PO54EO93 in Water

Contact Info

Product

Resources

About

Activation Thermodynamics and Concentration Scaling of the Viscosity of Unimeric and Aggregated Poloxamer EO₉₃PO₅₄EO₉₃ in Water