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Aachen, Techn. Hochsch., Habil.-Schr., 2012; Aachen : Publikationsserver der RWTH Aachen University 309 S. : Ill., graph. Darst. (2012). = Aachen, Techn. Hochsch., Habil.-Schr., 2012, This thesis describes the strongly interdisciplinary work carried out in the corrosion group at the Karl-Winnacker-Institute of DECHEMA e.V. on the development of new ways of corrosion protection for metals by a combination of chemical nanotechnology and materials sciences. On the one hand by following innovative nanotechnological concepts oxidic nanoparticles were used to produce or modify inorganic coating systems. On the other hand nano-scaled polymer films have been investigated as self-assembling adhesion promoter films and as biogenic protective coatings against microbially influenced corrosion processes., Published by Publikationsserver der RWTH Aachen University, Aachen

Diese Arbeit hat sich mit der Herstellung und Charakterisierung von Schichtsystemen für Verpackungsfolien auf Polymerbasis befasst. Anorganische Siliziumoxidschichten und Barrierelacke auf Basis von anorganisch-organischen Hybridpolymeren wurden auf die Polymerfolien aufgetragen um möglichst hohe Sperreigenschaften gegenüber Sauerstoff und Wasserdampf zu erzielen. Die produzierten Systeme wurden hinsichtlich ihrer Funktionalitäten getestet. Es wurde gezeigt, dass man mit einer Kombination dieser Barriereschichten auf einem Polymersubstrat sehr hohe Barriereeigenschaften erreichen kann. Weiterhin wurden Maßnahmen empfohlen, mit welchen eine weitere Verbesserung der Sperreigenschaften dieser Schichtsysteme möglich ist. The aim of the work was the production and characterisation of barrier layer systems for packaging films on polymeric basis. Inorganic silicon oxide layers and barrier lacquers on basis of inorganic-organic hybrid polymers were coated on polymeric films with the target to achieve high oxygen and water vapour barrier properties. The produced systems were tested for their functionalities. It was demonstrated that the combination of barrier layers allows for a huge improvement of barrier properties of coated polymeric films. Further, measures for improvement of barrier properties of the produced systems could be derived from the results.

In this thesis several polymer materials have been investigated with respect to their application as optical chemo-sensors, which are based on molecule diffusion into thin sensitive layers. The dynamic response of such sensors is mainly controlled by the diffusion kinetics of the molecules in the film. The solution of the diffusion differential equation (2nd Fick’s law) in the case of thin films yields the temporary concentration profile of the molecules in the film. Linearity between the refractive index changes and the concentration follows directly from the Lorentz-Lorenz equation and therefore gives the same variation for the index changes. With that the development of the refractive index profile during in- and out-diffusion is well described by the diffusion theory and consequently the dynamic response of the optical sensor can be modelled by a suitable theory. Thin glass/silver/polymer multilayer systems have been characterised with respect to their optical sensing parameters by using metal film enhanced leaky mode spectroscopy. This useful optical technique, which offers the observation of the surface plasmon resonance and the leaky modes of thin dielectric films, has been improved for the analysis of inhomogeneous refractive index profiles by using a transfer-matrix formalism for layered media. Furthermore, waveguide birefringence experiments on thin anisotropic polyimide films as planar lightguides have been carried out to show how the sensitivity of the sensor can be optimised by a suitable choice or a specific modification of the polymer material.