Module Notes
Suspensions and Emulsions
This module will not be offered for this semester
Module Details
Acquaintance with dispersed systems (Definitions, preparation, characterization)
Deviation of electrolyte solutions from ideal behaviour. Ion-ion interactions.
Mechanism of development of surface charge on particles suspended in electrolyte solutions
Methods and techniques of measurement of surface charge of colloids suspended in electrolyte solutions
Films and Foams
Stability of colloid suspensions and of foams. Theoretical and practical aspects
Kinetics of destabilization of colloidal systems
Prerequisites desired: Knowledge of electrolyte solutions theory
Dispersed matter. Liposomes and emulsions. The solid-liquid interface. DEBYE-HUCKEL theory for electrolytes. Extension to charged interfaces. The electrical double layer. Negative adsorption, Donnan equilibria and ion exchange. The point of zero charge. Thermodynamic analysis of the electrical double layer. The electrocapillary curve (Lippmann equation). Experimental measurements of the electro capillary curves and their significance for the electrical double layer parameters. Specific adsorption. Potentiometric titrations. Surface and ζ potential. Electrokinetic phenomena. Films and foams and their respective stability. The role of surfactants and drain. Repulsion between approaching double layers. Stability of lyophobic colloids. The DLVO theory. The Schultze-Hardy rule. The interaction between two particles. The Hamaker coefficient. The aggregation concentration
Teaching Organization
LECTURES: 3 h/w
PROJECT / HOMEWORK: 5/semester
Total Module Workload (ECTS Standards):
Final mark based on the final written exam. Homework assignments are taken into consideration.
- Κ. Παναγιώτου, “Διεπιφανειακά Φαινόμενα & Κολλοειδή Συστήματα”, Εκδ. Ζήτη, Θεσσαλονίκη, 1998.
- Π.Κουτσούκος, “Χημεία Κολλοειδών”, Πανεπιστήμιο Πατρών, 1996
- P.C.Hiemenz, R.Rajagopalan, “Principles of Colloid and Surface Chemistry”, 3rd Ed. CRC Press, 1997
- D.J.Shaw, “Introduction to Colloid and Surface Chemistry”, 4th ed., Butterworth-Heinemann, Oxford, 1992