For the analysis of polymers soft ionization mass spectrometry, in whi
ch only molecular ions are observed, can provide the complete distribu
tion of chains (length, composition, end-groups) in under ten minutes
on microgram quantities of material. Moreover, molecular ion informati
on of neat organic pigments or those present in crosslinked networks c
an also be furnished. No other analytical technique can supply these d
ata in such a short time. The application of mass spectrometry to the
characterization of materials used in today's high performance automot
ive coatings is presented. These include functional monomers, several
acrylic copolymers, organic pigments and an epoxide prepolymer. While
there are a variety of mass spectrometric techniques, in this paper we
will highlight the techniques that we have found useful for the chara
cterization of organic coating components. The selection of the mass s
pectrometric technique is dictated by the molecular weight of the mate
rial and to a lesser extent the chemical composition. We used potassiu
m ionization of desorbed species (K+IDS) performed on a quadrupole mas
s spectrometer for materials under 1000 Daltons (Da). However, many of
the ingredients used in current automotive finishes fall between 1000
and 10 000 Da. For these materials we used a Fourier transform mass s
pectrometer (FTMS) which is well suited for this mass range and boasts
the highest resolution and mass accuracy available. Direct desorption
/ionization using a carbon dioxide laser is our standard method of sam
ple introduction. Recently, we coupled a gel permeation chromatograph
to our FTMS using an electrospray ionization interface. This hyphenate
d technique offers one of the most powerful characterization methods f
or the coatings chemist. (C) 1998 Elsevier Science S.A. All rights res
erved.