Doctoral thesis (Dissertations and theses)
Nichtgleichgewichtsphänomene, Strukturbildung und Grenzflächeneinflüsse in netzwerkbildenden Systemen aus optischer und akustischer Sicht.
Philipp, Martine
2009
 

Files


Full Text
Philipp-Thesis.pdf
Author postprint (3.04 MB)
Download

All documents in ORBilu are protected by a user license.

Send to



Details



Keywords :
Nichtgleichgewichtsprozesse; Isostrukturelle Phasenübergänge; Grenzflächen; Interphasen; Chemische und physikalische Netzwerkbildung; Epoxid; Brillouin Spektroskopie
Abstract :
[en] Isostructural phase transitions occurring under non-equilibrium conditions are investigated using technologically relevant epoxies. The evolution of the hypersonic and optical properties during the genesis of the polymeric network leads to deeper insight into the chemically induced sol-gel transition and glass transition, as demonstrated e.g. by the elastic anharmonicity and the generalised Cauchy relation. During gelation the refractive index versus chemical conversion behaves in an unexpected manner, indicating that in addition to the mass density an excess polarisability seems to contribute to the optical polarisability. The clarification of the isostructural phase transitions is impeded by the demixing tendency of the epoxy components which leads to different types of epoxy inhomogeneities on the nano- to mesoscopic scale. Taking benefit from a sample arrangement where both epoxy components are layered, the spatio-temporal evolution of acoustic properties gives supplementary information about trans-interfacial transport and structure formation processes. Of special technological relevance, but also of fundamental interest, is the influence of nanoscopic disturbances placed into the epoxy matrix. So-called interphases surrounding the nanoparticles modify and complicate the epoxy network formation, leading to long-lived metastable morphologies and properties. The role of the mixing sequence of the epoxy resin, the hardener and the nanoparticles for the polymerised epoxy state and the transient states during network formation, as well as the isostructural phase transitions is further elucidated.
Disciplines :
Physics
Author, co-author :
Philipp, Martine ;  University of Luxembourg > Faculty of Science, Technology and Communication (FSTC) > Physics and Materials Science Research Unit
Language :
German
Title :
Nichtgleichgewichtsphänomene, Strukturbildung und Grenzflächeneinflüsse in netzwerkbildenden Systemen aus optischer und akustischer Sicht.
Defense date :
20 November 2009
Institution :
Unilu - University of Luxembourg, Luxembourg, Luxembourg
Degree :
Docteur en Physique
Promotor :
Krüger, Jan-Kristian
Available on ORBilu :
since 11 February 2014

Statistics


Number of views
114 (1 by Unilu)
Number of downloads
410 (0 by Unilu)

Bibliography


Similar publications



Contact ORBilu