Drier influence on the curing of linseed oil

Fourier transform infrared spectroscopy has been used to investigate the oxidative polymerisation of linseed oil in presence of cobalt 2-ethylhexanoate drier. Cobalt drier addition provokes the acceleration of all reactions involved in oxidation and the formation of surface solid film. Quantification of oxidation products using SF4 and NO treatments show lower concentrations in carboxylic acids, ketones and alcohols, for films cured with cobalt drier. Photoacoustic spectroscopy has been used to analyse oxidation profiles at the surface of the solid film formed in presence of cobalt drier. Efficiency as peroxides decomposers of cobalt, zirconium and calcium/zirconium drier, alone and in combination, were compared, by measuring variations of the peroxide value as a function of oxidation time. Indeed, peroxide value determination in oxidised drying oils can be considered as a measure of the extent of curing. II was shown that the activity of primary drier (Co) was modified by addition of secondary drier such as Zr or Ca/Zr. (C) 2000 Elsevier Science S.A. All rights reserved.