Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Development of ATR-FTIR Kretschmann Spectroscopy for In situ Studies of Metal / Polymer Interfaces: and its Intergration with EIS for Exposure to Corrosive Conditions
KTH, School of Chemical Science and Engineering (CHE), Chemistry, Corrosion Science.
2010 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The environmental stability of a metal / polymer interface is essential for the durability and mechanical stability of constructions in several important areas such as the automotive, offshore, building and aerospace industries. The protective capability of a polymer film is strongly connected to its barrier properties, but the transport of water and corrosive constituents through the polymer and the subsequent processes at the metal surface are complicated to analyse in detail. The surface to be analysed is confined between two media that are impermeable to most probing particles used in conventional analytical techniques. Several methods exist to describe separate parts of the system, but few techniques work atambient pressure and have the capacity to conduct real-time analysis at relevant exposure conditions. In this work, attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) in the Kretschmann geometry was successfully employed for systematic studies of metal / polymer interfaces. This technique requires the use of thin metal films deposited on an internal reflection element (IRE). Most studies were performed on aluminium, which is an important structural light-weight material, but also zinc was analysed, being frequently used for corrosion protection of steel. Upon exposure to water and electrolytes, the ATR-FTIR Kretschmann technique was found capable to monitor and to separate early deterioration related processes at the aluminium / polymer interface, including water sorption and transport of ionic species through the polymer film. Other main processes identified were the formation of corrosion products and swelling of the surface-near polymer network. To perform more comprehensive interpretations, a spectro-electrochemical method was further developed for in situ studies of the hidden metal / polymer interfaces. The ATR-FTIR Kretschmann technique was here combined with the complementary acting technique, Electrical Impedance Spectroscopy (EIS). The integrated set-up was able to provide complementary information, with ATR-FTIR Kretschmann being sensitive to the surface-near region and EIS to the whole system. For instance, metal oxidation and delamination processes can be difficult to distinguish by EIS, while on the other hand oxidation and hydration reactions on aluminiumcan be confirmed as IR bands at distinct positions. Delamination and swelling of a polymer both result in negative bands in an IR spectrum, but these processes may be distinguished by EIS as alterations in different frequency regions. While traditional chemical pre-treatments for enhanced hydrolytic stability perform excellent, they are being phased out from industrial applications due to environmental concerns and work health issues. Today there is an intense ongoing research regarding the mechanisms and performance of environmentally friendly pretreatments to develop systems of similar performance, and the analysis of the confined metal / polymer interface is crucial for this development. The capability of the integrated in situ ATR-FTIR Kretschmann and EIS set-up was therefore further applied to systems where a surface pre-treatment had been applied to the metal prior to the organic coating. Studies were first performed on vacuum-evaporated films of zinc treated with a titanium-based conversion coating and further coated with a UV-curing polymer. Alterations of the conversion layer could be detected upon exposure to the electrolyte. Also alkaline-cleaned aluminium coated with an amino-functional silane film and a thermo-curing epoxy top-coat was thoroughlycharacterized by both ATR-FTIR and IRRAS and further investigated upon exposure toelectrolyte and humid air. Changes at the hidden interface were detected upon thermal curingof the epoxy film and during exposure in electrolyte, and the in situ ATR-FTIR Kretschm annanalysis showed a high sensitivity towards alterations in the interfacial region. Complementary studies in the absence of metal could confirm a water uptake within the silane film and water-induced alterations of the siloxane network.

Place, publisher, year, edition, pages
Stockholm: KTH , 2010. , vi, 60 p.
Series
Trita-CHE-Report, ISSN 1654-1081 ; 2010:47
National Category
Physical Chemistry
Identifiers
URN: urn:nbn:se:kth:diva-26996ISBN: 978-91-7415-782-6 (print)OAI: oai:DiVA.org:kth-26996DiVA: diva2:374006
Public defence
2010-12-03, F3, Lindstedtsvägen 26, entréplan, KTH, Stockholm, 10:00 (English)
Opponent
Supervisors
Note
QC 20101222Available from: 2010-12-02 Created: 2010-12-02 Last updated: 2011-02-03Bibliographically approved
List of papers
1. In situ ATF-FTIR studies of the aluminium/polymer interface upon exposure to water and electrolyte
Open this publication in new window or tab >>In situ ATF-FTIR studies of the aluminium/polymer interface upon exposure to water and electrolyte
2006 (English)In: Progress in organic coatings, ISSN 0300-9440, Vol. 57, no 1, 78-88 p.Article in journal (Refereed) Published
Abstract [en]

Attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) with the Kretschmann configuration was applied for in situ studies of the transport of water and ionic species through a polymer film to an aluminium/polymer interface. The time dependent intensity changes of the infrared bands of water were used to follow the transport of water to the aluminium/polymer interfacial region and a NaSCN solution was employed as model electrolyte to follow the transport and accumulation of thiocyanate ions. Apart from water sorption and ion transport, the main processes identified were corrosion/oxidation of the aluminium surface and swelling of the polymer film. The method proved to be useful for detailed in situ studies of changes at a polymer coated metal surface, such as oxidation and surface film formation on the metal. It should also be possible to study the effects of defects and pores in the polymer film on the transport properties of water and ions to the metal/polymer interface, as well as adsorption and other chemical reactions and physical interactions in the metal/polymer interfacial region.

Keyword
Aluminium, ATR-FTIR, Coating, Interface, Water uptake
National Category
Other Chemistry Topics
Identifiers
urn:nbn:se:kth:diva-6635 (URN)10.1016/j.porgcoat.2006.07.002 (DOI)000241021200010 ()2-s2.0-33748162158 (Scopus ID)
Note
QC 20101122Available from: 2006-12-15 Created: 2006-12-15 Last updated: 2010-12-02Bibliographically approved
2. A spectroelectrochemical study of metal/polymer interfaces by simultaneous in situ ATR-FTIR and EIS
Open this publication in new window or tab >>A spectroelectrochemical study of metal/polymer interfaces by simultaneous in situ ATR-FTIR and EIS
2007 (English)In: Electrochemical and solid-state letters, ISSN 1099-0062, Vol. 10, no 4, C27-C30 p.Article in journal (Refereed) Published
Abstract [en]

Buried aluminum/polymer interfaces were studied using a spectroelectrochemical experimental setup based on simultaneous in situ attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) and electrical impedance spectroscopy (EIS). Transport of water and electrolyte through the polymer film to the aluminum/polymer interface and oxidation/corrosion of aluminum was followed by ATR-FTIR, while the impedance behavior of the system was simultaneously studied by EIS. As the ATR-FTIR technique is specific for the aluminum/polymer interfacial region while EIS takes into account alterations of both the polymer bulk and the interface, the combined setup provides complementary information of the system investigated.

Keyword
electrochemical impedance spectroscopy, organic coatings, water, metals, thiocyanate, electrolyte, films, configuration, performance, absorption
Identifiers
urn:nbn:se:kth:diva-16375 (URN)10.1149/1.2436647 (DOI)000244071400015 ()2-s2.0-33846984579 (Scopus ID)
Note
QC 20100525Available from: 2010-08-05 Created: 2010-08-05 Last updated: 2010-12-02Bibliographically approved
3. An integrated in situ ATR-FTIR and EIS study of buried metal/polymer interfaces exposed to an electrolyte solution
Open this publication in new window or tab >>An integrated in situ ATR-FTIR and EIS study of buried metal/polymer interfaces exposed to an electrolyte solution
2007 (English)In: Electrochimica Acta, ISSN 0013-4686, E-ISSN 0019-4686, Vol. 52, 5159-5171 p.Article in journal (Refereed) Published
Abstract [en]

In situ studies of buried aluminium/polymer interfaces were performed by combining Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR) with Electrochemical Impedance Spectroscopy (EIS). The capability of this integrated analytical set-up was explored by studying the characteristics of three different aluminium/polymer systems upon exposure to a 1 M NaSCN solution. Various qualifications of the systems were distinguished and the ingress of water and electrolyte, oxidation/corrosion of aluminium, swelling of the polymer and delamination were identified. This new set of complementary acting tools provides comprehensive information of the aluminium/polymer system, with ATR-FTIR being specific for the surface-near region and EIS taking into account changes within the whole system. While oxidation/corrosion and delamination are processes difficult to distinguish by EIS, oxide formation could be confirmed by ATR-FTIR. While it may be difficult to distinguish between delamination and polymer swelling with ATR-FTIR, these processes were more easily identified with EIS.

Keyword
IMPEDANCE SPECTROSCOPY, COATED ALUMINUM, OXIDE-FILMS, PART II, WATER, EPOXY, THIOCYANATE, CORROSION, SPECTRA, CONFIGURATION
Identifiers
urn:nbn:se:kth:diva-6637 (URN)10.1016/j.electacta.2007.02.007 (DOI)000246292100004 ()
Note
QC 20101122Available from: 2006-12-15 Created: 2006-12-15 Last updated: 2010-12-02Bibliographically approved
4. In situ studies of conversion coated zinc/polymer surfaces during exposure to corrosive conditions
Open this publication in new window or tab >>In situ studies of conversion coated zinc/polymer surfaces during exposure to corrosive conditions
2010 (English)In: Progress in organic coatings, ISSN 0300-9440Article in journal (Refereed) Published
Abstract [en]

This work investigates the hidden interface between a conversion-coated zinc surface and a polymer coating upon exposure to an electrolyte by simultaneous in situ ATR-FTIR and EIS. Various system properties were distinguished, such as the ingress of electrolyte constituents, and an active process of water-induced alterations of the conversion layer. The interface between a polymer film and a surface treated metal surface is of considerable fundamental and technical interest in many areas of application, and the results obtained open up the use of this method for a wide range of important applications.

Keyword
ATR-FTIR, Spectro-electrochemistry, Interface, Conversion coating, Zinc
Identifiers
urn:nbn:se:kth:diva-26328 (URN)10.1016/j.porgcoat.2010.09.012 (DOI)000285904000003 ()2-s2.0-78649631493 (Scopus ID)
Note
QC 20101122Available from: 2010-11-22 Created: 2010-11-22 Last updated: 2012-02-14Bibliographically approved

Open Access in DiVA

fulltext(1112 kB)2812 downloads
File information
File name FULLTEXT02.pdfFile size 1112 kBChecksum SHA-512
3fd7390dff38b81507be623f50751f71495d1802612cb216868de86a8fd7f65998ea734ad9db750741a0b90f8ccdee48c5dfb4bacde3668f0be0cbc00d646d8d
Type fulltextMimetype application/pdf

Search in DiVA

By author/editor
Öhman, Maria
By organisation
Corrosion Science
Physical Chemistry

Search outside of DiVA

GoogleGoogle Scholar
Total: 2821 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 533 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf