Dresden 2009 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
CPP: Fachverband Chemische Physik und Polymerphysik
CPP 23: Electronic and Optical Properties
CPP 23.11: Vortrag
Mittwoch, 25. März 2009, 16:45–17:00, ZEU 114
Effect of chemical architecture on light-induced deformation in azobenzene polymer films — •Marina Saphiannikova1, Vladimir Toshchevikov1,2, and Gert Heinrich1 — 1Leibniz-Institut für Polymerforschung, Dresden, Germany — 2Institute of Macromolecular Compounds, Saint-Petersburg, Russia
Photoresponsive azobenzene polymers have been extensively explored as highly functional materials which have a fascinating potential for technical applications (data storage media, artificial muscles, etc). We propose a microscopic theory which describes the light-induced deformations in amorphous azobenzene polymers taking the chemical architecture of macromolecules explicitly into account. Our theory provides the values of the light-induced stress comparable and higher than the values of yield stress typical for glassy polymers. Thus, the theory explains the possibility for the inscription of surface relief gratings in glassy azobenzene polymers in the absence of light-induced softening. We show that the photo-elastic behaviour of azobenzene polymers is very sensitive to the chemical architecture. Depending on the chemical architecture, a sample can be either stretched or uniaxially compressed along the electric vector of the linearly polarized light. For some chemical architectures, elongation of a sample displays a non-monotonic behaviour with the light intensity. These predictions are in agreement with experimental observations [1] and MD simulations [2].
This work was supported by the RFBR (08-03-00150).
[1] D.Bublitz et al. Appl. Phys. B 2000, 70, 863
[2] J.Ilnytskyi et al. MCLC 2008, 496, 186