Combined in-situ spectroscopic and electrochemical studies of interfacial and interphasial reactions during adsorption and de-adhesion of polymer films on metals [Elektronische Ressource] / submitted by Monika Santa

Santa

Informations

• Publié par: universitat_paderborn
• Publié le: 01 janvier 2010
• Nombre de lectures: 45
• Langue: English
• Poids de l'ouvrage: 4 Mo

Extrait

Combined in-situ spectroscopic and
electrochemical studies
of interfacial and interphasial reactions
during adsorption and de-adhesion
of polymer films on metals





PhD Thesis
Dr. rer. nat.


Faculty of Science
at the
University of Paderborn



Submitted by
Monika Santa
from Düsseldorf



Paderborn, July 2010


























Submitted: 14 May 2010

Defence: 22 June 2010


First referee: Prof. Dr.-Ing. Guido Grundmeier
Second referee: Prof. Dr. Wolfgang Bremser Acknowledgement
The present work was performed at the Max-Planck-Institut für Eisenforschung in the
working group of Prof. Dr.-Ing. Guido Grundmeier. I would like to thank him for the
opportunity to work under his supervision in Düsseldorf and Paderborn. With his support and
productive discussions he helped me to improve my scientific work and conclude my PhD.
Prof. Dr. Wolfgang Bremser gets my acknowledgment for refereeing my thesis and his
comments.

I would like to thank Dr. Ralf Posner for many fruitful discussions and an efficient
cooperation. Further, I would like to thank Dr.-Ing. Haybat Itani. In our collaboration I had
the opportunity to learn a lot about polyelectrolyte systems.
I am grateful to my dear collegues Dr. Nicole Fink, Dipl.-Chem. Katharina Pohl, M.Sc. Julia
Lengsfeld, Olesja Stöhr, Dr. Patrick Keil, Dr.-Ing. Juan Zuo, Dr. Markus Valtiner and Dipl.-
Phys. Romina Krieg, who supported me with their comments and helped me anytime. I would
also like to thank my former colleagues Dipl.-Phys. René Vlasak, who helped me with IR
spectroscopy, Dr. Ingo Klüppel for advice in electrochemical questions, and Dr. Tobias Titz
for his help with the plasma deposition of TMDS and SKP measurements. I would like to
thank my new colleague Dr. Cindy Münzenberg for helping me with corrections of the
present work.
Further, I would like to thank Monika Nellessen for the FIB preparation of my polymer
samples and SEM analysis. Ralf Selbach and the workshop made it possible to build my in-
situ SERS cell.

I thank Philipp for his unlimited patience and grate support particularly during the last year of
my PhD time.

The present work was carried out with the financial support of Cognis GmbH, Düsseldorf.








Ich versichere, dass ich diese Arbeit eigenständig verfasst und keine anderen als die
angegebenen Quellen und Hilfsmittel benutzt, sowie Zitate kenntlich gemacht habe.




Content

1 Motivation................................................................................................................... 5
2 Introduction................................................................................................................. 7
2.1 Transport of small molecules and ions in polymers.................................................... 7
2.2 Vibrational spectroscopy at polymer/metal interfaces................................................ 9
2.2.1 Vibrational spectroscopy in corrosion science................................................. 10
2.2.2 Buried polymer/metal interfaces ...................................................................... 10
2.3 Fundamentals of adhesion and de-adhesion of polymers on oxides ......................... 11
2.4 Adhesion mechanisms of organosilanes on oxides................................................... 12
2.5 Corrosive de-adhesion of polymers on zinc and iron substrates............................... 13
3 Experimental.............................................................................................................15
3.1 Applied techniques....................................................................................................
3.1.1 Spectroscopic techniques.................................................................................15
3.1.1.1 IR spectroscopy............................................................................................15
3.1.1.2 Surface enhanced Raman spectroscopy (SERS) .......................................... 16
3.1.1.3 X-ray photoelectron spectroscopy (XPS)..................................................... 16
3.1.1.4 Time-of-flight secondary ion mass spectrometry (ToF-SIMS).................... 17
3.1.2 Electrochemical techniques..............................................................................17
3.1.2.1 Scanning Kelvin Probe (SKP)...................................................................... 17
3.1.2.2 Electrochemical impedance spectroscopy (EIS).......................................... 19
3.1.3 Microscopic techniques....................................................................................20
3.1.3.1 Scanning electron microscopy (SEM).......................................................... 20
3.1.3.2 Focused ion beam (FIB)............................................................................... 21
3.1.4 Adhesion tests..................................................................................................21
3.1.5 Contact angle measurement ............................................................................. 21
3.2 Sample preparation....................................................................................................22
4 Comparison of water uptake in solvent and water borne epoxy-amine polymers .... 25
4.1 Film formation...........................................................................................................25
4.1.1 Bulk and interface reaction during film formation........................................... 25
4.1.2 Surface energy during film formation.............................................................. 29
4.2 Water uptake and diffusion ....................................................................................... 31
4.2.1 EIS study..........................................................................................................31
4.2.2 ATR-IR study...................................................................................................34
4.3 Polymer/substrate interface and adhesion................................................................. 38
4.4 Conclusions...............................................................................................................42 5 Organosilane adhesion promoters in water and solvent borne epoxy-amine polymers
................................................................................................................................... 45
5.1 Water uptake of modified water and solvent borne coating...................................... 45
5.1.1 Application of GPS as adhesion promoter ....................................................... 46
5.1.2 Application of APS as a 50
5.2 Polymer/substrate interface and adhesion................................................................. 53
5.2.1 dhesion promoter 54
5.2.2 56
5.3 Conclusions...............................................................................................................62
6 Kelvin probe studies of interfacial wet de-adhesion and corrosion ......................... 65
6.1 Cathodic delamination at the water and solvent borne epoxy-amine/steel interfaces
................................................................................................................................... 66
6.1.1 Cathodic delamination on iron-zinc samples ................................................... 66
6.1.2 ination on steel substrates ....................................................... 66
6.1.3 Effects of reduced humidity on the corrosion process ..................................... 69
6.2 Cathodic delamination of the GPS-modified water borne epoxy-amine film........... 74
6.2.1 ination at reduced humidity..................................................... 74
6.3 ination of the APS-modified water and solvent borne epoxy-amine
film ............................................................................................................................ 78
6.4 Conclusions...............................................................................................................81
7 Molecular understanding of adhesion and diffusion in corrosion protection coatings
................................................................................................................................... 83
7.1 Competitive adsorption of organosilanes and epoxy-amine model molecules on iron
oxide surfaces............................................................................................................ 84
7.1.1 Adsorption of organosilanes on covered iron oxide surfaces .......................... 84
7.1.2 Adsorption of hardener and APS on iron oxide depending on APS
concentration .................................................................................................... 87
7.2 In-situ study of the deterioration of thiazole/gold and silver interfaces during
interfacial ion transport processes ............................................................................ 90