Premium
The use of high‐resolution XPS and ToF‐SIMS to investigate segregation phenomena of minor components of a model coil coating formulation
Author(s) -
Leadley S. R.,
Watts J. F.,
Blomfield C. J.,
Lowe C.
Publication year - 1998
Publication title -
surface and interface analysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.52
H-Index - 90
eISSN - 1096-9918
pISSN - 0142-2421
DOI - 10.1002/(sici)1096-9918(19980515)26:6<444::aid-sia387>3.0.co;2-5
Subject(s) - melamine resin , x ray photoelectron spectroscopy , coating , secondary ion mass spectrometry , epoxy , analytical chemistry (journal) , materials science , melamine , chemical engineering , chemistry , composite material , ion , organic chemistry , engineering
The segregation of minor components—a melamine–formaldehyde resin and a poly(acrylic) flow control agent—in a model epoxy resin coil coating applied to hot‐dipped galvanized steel has been investigated by high‐resolution XPS and time‐of‐flight SIMS (ToF‐SIMS). It is shown that by using the highest resolution monochromated XPS currently available, the C 1s spectrum can be peak fitted to account for all eleven carbon functionalities present in the three components of the organic coating. A ToF‐SIMS analysis of the melamine–formaldehyde resin has been undertaken and a comprehensive ion fragmentation scheme for the positive ion spectrum of this molecule in the range 0–500 Da is proposed. It is shown, by both surface analytical techniques, that when the flow control agent is excluded from the formulation the surface of the paint film is enriched in the melamine–formaldehyde component. On addition of the flow control agent such segregation is only identified by XPS; the ToF‐SIMS spectrum resembles that of the flow control agent. This is taken to be an indication of monolayer segregation of this component at the paint/air interface. Such segregation phenomena are shown to be insensitive to substrate surface pretreatment. © 1998 John Wiley & Sons, Ltd.