Depolarized dynamic light scattering from three low molecular weight glass forming liquids: A test of the scattering mechanism

1997 ◽  
Vol 106 (20) ◽  
pp. 8401-8408 ◽  
Author(s):  
A. Patkowski ◽  
W. Steffen ◽  
H. Nilgens ◽  
E. W. Fischer ◽  
R. Pecora
Keyword(s):  
Molecular Weight ◽  
Light Scattering ◽  
Dynamic Light Scattering ◽  
Low Molecular Weight ◽  
Scattering Mechanism ◽  
Glass Forming

Supramolecular Structures of Low-Molecular-Weight Polybutadienes, as Studied by Dynamic Light Scattering, NMR and Infrared Spectroscopy

2001 ◽  
Vol 34 (26) ◽  
pp. 9023-9031 ◽  
Author(s):  
Jiří Podešva ◽  
Jiří Dybal ◽  
Jiří Spěváček ◽  
Petr Štěpánek ◽  
Peter Černoch
Keyword(s):  
Molecular Weight ◽  
Infrared Spectroscopy ◽  
Light Scattering ◽  
Dynamic Light Scattering ◽  
Supramolecular Structures ◽  
Low Molecular Weight

Density and confinement effects of glass forming m-toluidine in nanoporous Vycor investigated by depolarized dynamic light scattering

2013 ◽  
Vol 138 (11) ◽  
pp. 114501 ◽  
Author(s):  
Thomas Blochowicz ◽  
Emmanuel Gouirand ◽  
Sebastian Schramm ◽  
Bernd Stühn
Keyword(s):  
Light Scattering ◽  
Dynamic Light Scattering ◽  
Confinement Effects ◽  
Glass Forming

scholarly journals COMPLEXATION OF POLYETHYLENE-GLYCOL WITH THE SODIUM SALTS OF CITRIC AND SUCCINIC ACIDS IN THE AQUEOUS SOLUTIONS. STUDIES BY DYNAMIC LIGHT SCATTERING AND UV/VIS SPECTROPHOTOMETRY

2015 ◽  
Vol 11 (8) ◽  
pp. 3866-3872
Author(s):  
E.A. Masimov ◽  
Etibar Hummat Ismailov ◽  
S.Y. Odzhaqverdiyeva
Keyword(s):  
Molecular Weight ◽  
Light Scattering ◽  
Dynamic Light Scattering ◽  
Aqueous Solutions ◽  
Polyethylene Glycols ◽  
Hydrodynamic Diameter ◽  
Absorption Bands ◽  
Sodium Salts ◽  
And Diffusion ◽  
Formation Of Complexes

Dynamic light scattering (DLS) method in combination with the UV/VIS spectrophotometry is used to study the interaction of polyethylene- glycols with a molecular weight  6000 ( PEG6000 ) with sodium salts of citric and succinic acids in aqueous solutions. The values of density, viscosity, refractive and diffusion indexes, the values of the hydrodynamic diameter, wavelength electronic absorption bands for PEG6000 aqueous solutions, their mixtures with succinic and citric acids are determined. It was shown that depending on the composition of the solutions the values of hydrodynamic diameter for aqueous solutions containing 1-5 wt.% PEG6000 and their mixtures with succinic and citric acids (~ 1 wt%) ranges from 3.6 to 5.2 nm. It is assumed that the formation of complexes with the sizes  that are within the above range is due to the features of interaction  and the structure of the complexes formed in solution.

scholarly journals Activation volume in superpressed glass-formers

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Aleksandra Drozd-Rzoska
Keyword(s):  
Molecular Weight ◽  
Relaxation Time ◽  
Absolute Stability ◽  
Activation Volume ◽  
Stability Limit ◽  
Low Molecular Weight ◽  
Glass Forming ◽  
Deep Earth ◽  
Structural Relaxation Time ◽  
The Given

Abstract In pressurized glass-forming systems, the apparent (changeable) activation volume Va(P) is the key property governing the previtreous behavior of the structural relaxation time (τ) or viscosity (η), following the Super-Barus behavior: $${\boldsymbol{\tau }}{\boldsymbol{(}}{\boldsymbol{P}}{\boldsymbol{)}}{\boldsymbol{,}}{\boldsymbol{\eta }}{\boldsymbol{(}}{\boldsymbol{P}}{\boldsymbol{)}}{\boldsymbol{\propto }}{\bf{\exp }}{\boldsymbol{(}}{{\boldsymbol{V}}}_{{\boldsymbol{a}}}{\boldsymbol{(}}{\boldsymbol{P}}{\boldsymbol{)}}{\boldsymbol{/}}{\boldsymbol{R}}{\boldsymbol{T}}{\boldsymbol{)}}$$ τ ( P ) , η ( P ) ∝ exp ( V a ( P ) / R T ) , T = const. It is usually assumed that Va(P) = V#(P), where $${{\boldsymbol{V}}}^{{\boldsymbol{\#}}}{\boldsymbol{(}}{\boldsymbol{P}}{\boldsymbol{)}}={\boldsymbol{R}}{\boldsymbol{T}}{\boldsymbol{d}}\,{\boldsymbol{ln}}\,{\boldsymbol{\tau }}{\boldsymbol{(}}{\boldsymbol{P}}{\boldsymbol{)}}{\boldsymbol{/}}{\boldsymbol{d}}{\boldsymbol{P}}$$ V # ( P ) = R T d ln τ ( P ) / d P or $${{\boldsymbol{V}}}^{{\boldsymbol{\#}}}{\boldsymbol{(}}{\boldsymbol{P}}{\boldsymbol{)}}{\boldsymbol{=}}{\boldsymbol{R}}{\boldsymbol{T}}{\boldsymbol{d}}\,{\boldsymbol{ln}}\,{\boldsymbol{\eta }}{\boldsymbol{(}}{\boldsymbol{P}}{\boldsymbol{)}}{\boldsymbol{/}}{\boldsymbol{d}}{\boldsymbol{P}}$$ V # ( P ) = R T d ln η ( P ) / d P . This report shows that Va(P) ≪ V#(P) for P → Pg, where Pg denotes the glass pressure, and the magnitude V#(P) is coupled to the pressure steepness index (the apparent fragility). V#(P) and Va(P) coincides only for the basic Barus dynamics, where Va(P) = Va = const in the given pressure domain, or for P → 0. The simple and non-biased way of determining Va(P) and the relation for its parameterization are proposed. The derived relation resembles Murnaghan - O’Connel equation, applied in deep Earth studies. It also offers a possibility of estimating the pressure and volume at the absolute stability limit. The application of the methodology is shown for diisobutyl phthalate (DIIP, low-molecular-weight liquid), isooctyloxycyanobiphenyl (8*OCB, liquid crystal) and bisphenol A/epichlorohydrin (EPON 828, epoxy resin), respectively.

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