Dresden 2006 – wissenschaftliches Programm
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CPP: Chemische Physik und Polymerphysik
CPP 27: POSTER Polymer Physics and Materials
CPP 27.43: Poster
Donnerstag, 30. März 2006, 17:00–19:00, P2
Probing Micromechanical Behavior of Semicrystalline Polypropylene Films by Brillouin Spectroscopy — •Olga Priadilova1, Wei Cheng1, Werner Steffen1, Jochen Gutmann1, and George Fytas1,2 — 1Max-Planck for Polymer Research, D-55128 Mainz, Germany — 2Department of Materials Science and Technology,University of Crete and FO.R.T.H P.O.Box 1527, 71110 Heraklion, Greece
The elastic properties of polypropylene films crystallized under different conditions were investigated via Brillouin spectroscopy measurements. It was found that elastic constants of the polypropylene films are dependent on their microstructure. Inelastic Brillouin light scattering from films reveals the presence of up to four bulk and surface phonons. The coexistence of amorphous and crystalline regions with at least submicron sizes allow for the propagation of two longitudinal and transverse elastic excitations. The relation of the acoustic excitations to the surface and bulk morphology of the semicrystalline films is supported by X-ray scattering techniques and optical microscopy images. Inelastic (Brillouin) light scattering from semicrystalline homopolymers can measure the high frequency elastic constant of the two microphases if the formed spherulites exceed the size of the wavelength of the probed phonons. In this case, the film is inhomogeneous over the relevant length scales and there is an access to the transverse phonon in the crystalline phase yielding the elastic constant as well.