Berlin 2005 – wissenschaftliches Programm

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CPP: Chemische Physik und Polymerphysik

CPP 5: SYMPOSIUM: Dynamics of multi-component fluids POSTER

CPP 5.31: Poster

Freitag, 4. März 2005, 17:15–19:00, Poster TU D

Phase Transitions of Block Copolymers under the Influence of External Noise — •Martin Kreis, Nicolaus Rehse und Robert Magerle — Physikalische Chemie II, Universität Bayreuth, D-95440 Bayreuth, Germany

Block copolymers tend to microphase separate and to form a rich variety of ordered structures on the mesoscale in thermodynamic equilibrium. We investigate thin films of polystyrene-block-polybutadiene with film thicknesses (< 100 nm) and lengths of the involved polymer blocks being convenient control parameters. As the films are swollen in a non selective solvent vapor they form a highly concentrated, viscous solution. Our interest is the dynamics of phase transitions between the different morphologies under the influence of external noise which is realized by either fluctuating the vapor pressure or the temperature. These transitions are followed in situ by tapping mode scanning force microscopy.