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Orientation, conformation and phase transitions of thin polymer films and self-assembled monolayers studied by SFG spectroscopy [Elektronische Ressource] / put forward by Volker Luiz Siegmar Kurz

145 pages
Dissertationsubmitted to theCombined Faculties for theNatural Sciences and for Mathematicsof the Ruperto{Carola University of Heidelberg, Germanyfor the degree ofDoctor of Natural SciencesPut forward byMaster of Science: Volker Luiz Siegmar KurzBorn in: Campinas, BrazilOral examination: February 1st, 2011Orientation, conformation and phasetransitions of thin polymer lms andself-assembled monolayers studied bySFG spectroscopyReferees: Prof. Dr. Michael GrunzeProf. Dr. Annemarie PucciOrientation, conformation and phase transitions of thin polymer lms andself-assembled monolayers studied by SFG spectroscopyThe aim of this dissertation was the characterization of thin polymeric lms on metal substrates. Ofspecial interest were lms of poly-N-isopropylacrylamide (pNIPAM). Their lower critical solution tem-perature (LCST) at 32 C makes this polymer attractive for many applications. The changes in themolecular structure and the dynamic of these changes at the LCST are related to macroscopic prop-erties. Using inherently interface speci c sum-frequency generation spectroscopy, gave insights intothe molecular arrangement even through bulk media. The molecular groups responsible for the phasetransition were identi ed and the inuence of the molecular weight was analyzed. Order parameterswere also deduced.
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Dissertation
submitted to the
Combined Faculties for the
Natural Sciences and for Mathematics
of the Ruperto{Carola University of Heidelberg, Germany
for the degree of
Doctor of Natural Sciences
Put forward by
Master of Science: Volker Luiz Siegmar Kurz
Born in: Campinas, Brazil
Oral examination: February 1st, 2011Orientation, conformation and phase
transitions of thin polymer lms and
self-assembled monolayers studied by
SFG spectroscopy
Referees: Prof. Dr. Michael Grunze
Prof. Dr. Annemarie PucciOrientation, conformation and phase transitions of thin polymer lms and
self-assembled monolayers studied by SFG spectroscopy
The aim of this dissertation was the characterization of thin polymeric lms on metal substrates. Of
special interest were lms of poly-N-isopropylacrylamide (pNIPAM). Their lower critical solution tem-

perature (LCST) at 32 C makes this polymer attractive for many applications. The changes in the
molecular structure and the dynamic of these changes at the LCST are related to macroscopic prop-
erties. Using inherently interface speci c sum-frequency generation spectroscopy, gave insights into
the molecular arrangement even through bulk media. The molecular groups responsible for the phase
transition were identi ed and the inuence of the molecular weight was analyzed. Order parameters
were also deduced. In order to obtain quantitative information from the SFG spectra a spectral simula-
tion program was implemented allowing for quanti cation of molecular orientation in the polymer lms
investigated. The composition of an n-layer system of the sample, angle of incidence, and molecular
symmetry groups were used as parameters. Furthermore, the existing SFG spectrometer was adapted
to investigate the solid/liquid interface using a freshly developed in situ cell as well as a novel pulse
shaping technique allowing for the clear separation of the spectral phase of vibrational resonances. A
reference beam line for absolute intensity measurements was also added. In addition, samples of self
assembled monolayers of oligo(ethylene glycol) OEG, often used as model systems for the understanding
of anti fouling materials, were investigated. The e ect of di erent aqueous environments, temperatures,
chain lengths and terminal groups on the conformations of the molecules in the lm were characterized.
Untersuchung von Orientierung, Konformation und Phasenubergangen von
dunnen Polymer

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