Regensburg 2007 – wissenschaftliches Programm

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CPP: Fachverband Chemische Physik und Polymerphysik

CPP 7: POSTER: INTERNAL SYMPOSIUM Scattering Experiments

CPP 7.19: Poster

Montag, 26. März 2007, 16:00–18:00, Poster B

Reversible Tuning of Block Copolymer Domain Spacings via Electric Fields — •Kristin Schmidt¹, Heiko Schoberth¹, Helmut Hänsel¹, Thomas Weiss², Volker Urban³, Alexander Böker¹, and Georg Krausch¹ — ¹Lehrstuhl für Physikalische Chemie II, Universität Bayreuth, D-95440 Bayreuth, Germany — ²European Synchrotron Radiation Facility (ESRF), F-38043 Grenoble, France — ³Oak Ridge National Lab (ORNL), Oak Ridge, TN 37831, USA

We investigate the influence of electric fields on the domain spacing of a lamellar forming diblock copolymer solution by time-resolved synchrotron small angle X-ray scattering. As a model system we use a polystyrene-b-polyisoprene block copolymer dissolved in toluene or tetrahydrofurane. We find a significant dependence of the characteristic spacing on the electric field strength. For lamellae aligned parallel to the electric field direction we observe a decreasing lamellar distance with increasing field strength, while for perpendicularly orientated lamellae the domain size is increasing. We investigate the influence of the electric field strength, the degree of phase separation, molecular weight, composition and the polarity of the solvent. Furthermore we monitor the relaxation kinetics and show the revesibility of the changes in domain spacing on application and turn off of the electric field.