Dresden 2003 – wissenschaftliches Programm
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CPP: Chemische Physik und Polymerphysik
CPP 20: POSTER A
CPP 20.2: Poster
Montag, 24. März 2003, 19:00–21:00, ZEU/250
Mesoscopic Fibrillation of Polymer Latex Films -Micromechanical Investigations Based on AFM Noise Analysis — •Tatiana Dimitrova1, Diethelm Johannsmann2, Norbert Willenbacher3, and Andreas Pfau3 — 1MPI for Polymer Research, Ackermannweg 10, D-55128 Mainz — 2Institute of Physical Chemistry, TU Clausthal, Arnold-Sommerfeld-Str. 4, — 3BASF AG, Polymerphysik, D-67056 Ludwigshafen
Slow pulling experiments with AFM tips were performed, where the thermal motion of the tip was monitored in parallel to the static force. The analysis of the thermal excitation of the cantilever, as the latter is withdrawn from the film surface, permitted to obtain in situ local mechanical parameters of the system AFM-tip?polymer filament. We monitored the time evolution of surface morphology of the studied films with conventional AFM. The fraction of successful pulls - meaning pulls where an extended adhesion hysteresis loop is observed - decreases with aging. Presumably, the internal cohesion of the material increases as film formation proceeds, such that the formation tip-induced deformations of the surface becomes less likely. For the tackiest material the formation of a continuous film was incomplete even after months of storage. This system exhibits the larger fraction of successful pulls as well. The evolution of the micro mechanical properties of the filaments is discussed.