Berlin 2015 – scientific programme

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CPP: Fachverband Chemische Physik und Polymerphysik

CPP 2: Focus: Field Controllable Functional Polymers I

CPP 2.1: Invited Talk

Monday, March 16, 2015, 09:30–10:00, C 264

Polymer films with optically controlled shape and functionality on a nanometer scale — •Svetlana Santer — Universität Potsdam

When azo-modified photosensitive polymer films are irradiated with light interference patterns, topographic variations in the film develop that follow the field vector distribution resulting in the formation of surface relief gratings (SRG). In my talk I plan to address two major points concerning the experimental efforts to understand SRG formation in azobenzene containing thin polymer films: (i) how is the orientation of the electric field vector within the interfering electromagnetic fields related to the topographical pattern within the SRG; (ii) how can one measure locally the opto-mechanical forces emerging during topography change. In the first part, I will present a new set-up combining an atomic force microscope (AFM) and two-beam interferometry, with which it is possible to track the topography change in-situ while at the same time changing polarization and phase of the impinging interference pattern. In the second part of my talk I will present how graphene can be utilized as a nanoscopic probe in order to characterize local opto-mechanical forces generated within photosensitive azobenzene containing polymer films. Based upon our experimental results we can deduce that internal stresses within the film due to grating formation can exceed 1 GPa. To demonstrate the strength of the opto-mechanical forces generated within the polymer film in the last part of my talk I will report on opto-mechanical scission of polymer chains in photosensitive polymer brushes.