Decoupling between thermodynamics and dynamics during rejuvenation in colloidal glasses

Abstract Four kinds of solvent were chosen to prepare poly(ether sulfones) (PES) filtration membranes by the nonsolvent induced phase separation (NIPS) method. Ternary phase diagram and shear viscosity measurement were conducted to analyse the formation of prepared membrane from thermodynamic and kinetic perspectives. The micro-structure of the membranes with different solvents were analysed, and the result showed a high relevance to the thermodynamics and dynamics of the casting solutions, and promoted the proposal of a reasonable membrane formation mechanism.

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What can be learnt from dielectric relaxation spectroscopy about ion solvation and association?

Pure and Applied Chemistry ◽

10.1351/pac200880061239 ◽

2008 ◽

Vol 80 (6) ◽

pp. 1239-1252 ◽

Cited By ~ 77

Author(s):

Richard Buchner

Keyword(s):

Dielectric Relaxation ◽

Ion Association ◽

Electrolyte Solutions ◽

Ion Solvation ◽

Dielectric Relaxation Spectroscopy ◽

Major Focus ◽

Solvent Interactions ◽

Solution Studies ◽

Key Features ◽

Thermodynamics And Dynamics

Ion solvation and ion association are key features of ion-solvent interactions, and their balance largely determines structure, thermodynamics, and dynamics of electrolyte solutions. Despite being studied for many years with various techniques, these effects are still intriguing because too often results obtained with different methods-each having its individual merits and limitations-cannot be connected properly due to lacking information. In this contribution, we would like to bring dielectric relaxation spectroscopy (DRS) as a further tool for solution studies to the attention of the audience. The principles of DRS and the required instrumentation are briefly introduced. The major focus will be on the kind of results obtained with this technique regarding ion solvation and association and how this information compares with results obtained from other techniques.

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Effects of Anion Impurities on the Solubility and Nucleation of Borax Decahydrate Crystals in Carbonate-Type Brine

Crystals ◽

10.3390/cryst9060304 ◽

2019 ◽

Vol 9 (6) ◽

pp. 304

Author(s):

Jing Chen ◽

Jiaoyu Peng ◽

Xingpeng Wang ◽

Yaping Dong ◽

Wu Li

Keyword(s):

Nucleation Theory ◽

Theory Approach ◽

Carbonate Solutions ◽

Common Ion ◽

Chloride Sulfate ◽

Metastable Zone ◽

Thermodynamics And Dynamics ◽

Hoff Equation ◽

And Diffusion ◽

Main Factor

Measurements of the solubility and metastable zone width (MSZW) of borax decahydrate (disodium tetraborate decahydrate) within chloride, sulfate and carbonate solutions were carried out. The MSZW was measured by the conventional polythermal method with turbidity technology. The results showed that the addition of impurities decreased solubility. The main factor reducing solubility is the common ion effect, but the salt effect is also significant in the complex system. The addition of impurities broadened the MSZW. The MSZW was wider at first, then decreased with the addition of NaCl, yet the MSZW widened with the addition of Na2SO4 within the concentration range studied. This can be explained by adsorption and diffusion. The data of solubility and MSZW were analyzed by applying the Van’t Hoff equation and the classical 3D nucleation theory approach, respectively. By calculating the corresponding parameters, the experimental phenomena are further explained from the perspective of thermodynamics and dynamics.

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