Academic Journal

Structural Relaxation and Thermodynamics of Viscous Aqueous Systems: A Simplified Reappraisal

التفاصيل البيبلوغرافية
العنوان: Structural Relaxation and Thermodynamics of Viscous Aqueous Systems: A Simplified Reappraisal
المؤلفون: Alberto Schiraldi
المساهمون: A. Schiraldi
سنة النشر: 2023
المجموعة: The University of Milan: Archivio Istituzionale della Ricerca (AIR)
مصطلحات موضوعية: Aqueous system, Viscosity, Excess entropy, Metastable state, Relaxation processe, “Dynamic” phase diagram, Settore CHIM/02 - Chimica Fisica
الوصف: The attainment of true equilibrium conditions is a dynamic process that encompasses a time span. For slow relaxing systems, non-quilibrium steady states can often look like equilibrium states. This is the case of viscoelastic systems, whose properties reflect their thermo-rheological history. After a summary of the seminal woks by Eyring, Adam & Gibbs and Angell, and mention of promising recent approaches that imply updated theoretical and experimental techniques, the paper suggests a simplified approach for aqueous systems, through a modified expression of the chemical potential of water and use of the “dynamic” phase diagram, so far proposed by Slade and Levine. For homogeneous systems (aqueous solutions), an extra term in the expression of the chemical potential accounts for the energy related to the residual strains produced during the thermo-rheological history of the system. This approach allows estimation of the effect of viscosity on the observed freezing point of polymer solutions. For heterogeneous systems (hydrogels, colloidal glasses), changes of the phase boundaries in the phase diagram explain the gel/sol hysteresis and the syneresis process as the result of water exchange between hosting meshes and trapped aqueous solution. Finally, physical hurdles that hinder inter-phase water displacements and/or the access to the headspace of the system can lead to the coexistence of aqueous phases with different aW within the same heterogeneous system.
نوع الوثيقة: article in journal/newspaper
اللغة: English
Relation: info:eu-repo/semantics/altIdentifier/wos/WOS:000919695900001; journal:JOURNAL OF SOLUTION CHEMISTRY; https://hdl.handle.net/2434/951891; info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-85146648271
DOI: 10.1007/s10953-022-01238-z
الاتاحة: https://hdl.handle.net/2434/951891
https://doi.org/10.1007/s10953-022-01238-z
Rights: info:eu-repo/semantics/openAccess
رقم الانضمام: edsbas.EA37C6C6
قاعدة البيانات: BASE
الوصف
DOI:10.1007/s10953-022-01238-z