Alkyd coating

I am a conservation student at the University of Canberra who is
just about to finish my honours dissertation.  The subject of my
dissertation is a horse-drawn vehicle with a coated upholstery
material (imitation leather) which I believe dates to between 1922
and 1938.

I have performed Fourier transform Infrared Spectroscopy which has
returned results of an alkyd and shellac.  I don't think that the
material is PVC.

I have then performed a Py-GC-MS analysis with a few of the top hits
in the NIST library being contemporary PVC plasticisers like Mono
(2-ethylhexyl) phthalate (MEHP) and 1,2-Benzenedicarboxylic acid,
butyl octyl ester (BOP).  Some of the other number one hits have
been Oleic acid, methyl ester and phthalic anhydride.  Many of the
mass spectra in my analysed sample have a M+ peak of around 345, and
some of the Nist hits are up around that molecular weight.  Many of
the mass spectra have the phthalate peak at 149.  As I am not really
that competent at reading these, I am wondering if I could be
finding these results of an alkyd (as they are phthalate esters) or
whether anyone else has encountered this in their work?


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                  Conservation DistList Instance 29:20
                 Distributed: Saturday, October 3, 2015
                       Message Id: cdl-29-20-013
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