Wetting Dynamics of Aqueous Surfactant Solutions on Polymer Surfaces - Drops and Bubbles in Contact with Solid Surfaces - page 71

Wetting Dynamics of Aqueous Surfactant Solutions
on Polymer Surfaces

Victoria Dutschk a , b , Alfredo Calvimontes b and Manfred Stamm b

a

Engineering of Fibrous Smart Materials (EFSM), Faculty for Engineering Technology (CTW),
University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands

b

Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Strasse 6, 01069 Dresden, Deutschland

Contents

A. Basics of Wetting . . .......................................... 71

1. Wetting and Wettability . . .................................... 72

2.ThreePhaseContact(TPC)Zone ................................ 72

3.ContactAngleHysteresis..................................... 73

B. Wetting on Rough Surfaces . . .................................... 74

1. Surface Roughness of Solids ................................... 75

2. Different Wetting Regimes .................................... 76

C. Wetting Dynamics . .......................................... 79

1.SpreadingTheories ........................................ 79

2.SpreadingasaRateProcess ................................... 80

3.SpreadingofAqueousSurfactantSolutions........................... 82

4. Spreading in Technological Applications ............................ 83

D.Summary ................................................ 90

E.Acknowledgements........................................... 90

F.References................................................ 90

A. Basics of Wetting

The physical bases of wetting are molecular interactions within a solid or liquid or
across the interface between a liquid and a solid. The wetting behavior of liquids
on solid surfaces is determined by surface tensions (strictly speaking by interfa-
cial tensions) of solid or liquid and liquid-solid interfacial tensions. Curvature and
roughness of contact surface are the two other critical factors for wetting phenom-
ena.