Characterisation of siccative oils, resins and pigments in art works by thermochemolysis coupled to thermal desorption and pyrolysis GC and GC-MS

Thermal desorption in the presence of tetramethylammonium hydroxide (TMAH) has been applied to materials belonging to the artistic field to verify the effectiveness of the derivatisation reaction. Thermal desorption of siccative oils and abietane resins give consistent results with traditional pyrolysis in methylation conditions, while as regard antraquinonic dyes the milder thermal treatment leads to the formation of more diagnostic compounds than pyrolysis.