ABSTRACT
Contents A. Introduction 138 B. Dilational rheology of adsorbed layers 139 1. Generalities on visco-elasticity of surfactant solution 139 2. Theoretical models 140 3. Surface rheology and relaxation phenomena 142 C. The oscillating Drop/Bubble methods 147 1 Drop/ Bubble Profile Tensiometry 148 2 Drop / Bubble Pressure Tensiometry 150 D. Experimental Results on Dilational Rheology 156 1 Non ionic Surfactant at water/air and water/oil interface 156 2 Polymers, Proteins and mixed systems 162 3 Nanoparticles at fluid interface 164 4 Microgravity experiments 168 E. Conclusions 172 F. References 173
A. INTRODUCTION
The mechanical behaviour of liquid interfaces has a large relevance for many technological and natural processes involving multiphase systems subjected to dynamic conditions. This behaviour is primarily linked to the value of the interfacial tension and to its instantaneous variation under the effect of changes of the available interfacial area, i.e, to the dilational rheology of the interfacial layer.
