Initiation of radical chains by singlet oxygen (1g), and their propagation underpin the mechanism of oxidation of linseed oil, leading to the self-heating and formation of volatile organic species and higher molecular weight compounds. The review also discusses the role of metal complexes of cobalt, iron and manganese in catalysing the oxidative drying of linseed oil, summarising some kinetic parameters such as the rate constants of the peroxidation reactions.
Peccianti, M., Lieg deres, F., Seyed Sadr, M., Sabau, C., Sharma, G., Blanchard, F., Razzari, L., Maret, D., Seyed Sadr, E., Alshami, J., Siu, V., Gobbi, G., Ozaki, T., Del Maestro, R. et Morandotti, R.. 2010. « Evaluation of the electromagnetic hazard of intense THz pulses on neural cells ». In Conference on Lasers and Electro-Optics (CLEO) and Quantum Electronics and Laser Science Conference (QELS), 2010 (San Jose, CA, USA, May 16-21, 2010) IEEE.
Linseed oil has found numerous applications in painting, varnishes, wood treatment and linoleum due to its drying properties. However, in the presence of a metal catalyst, the oxidation of linseed oil soaked into lignocellulosic materials, such as cotton rags, may induce their spontaneous heating. As a consequence of the importance of the unsaturated fatty acid (present in linseed oil as triacylglycerols) to nutrition, several studies have been undertaken to investigate the oxidation of the active components in linseed oil; often deploying surrogate compounds, such as ethyl linoleate. These studies led to establishing a generally good understanding of the overall radical chain reactions that operate in the oxidation process. The chemical reactions involve initiation, propagation and termination steps. They comprise oxygen addition to the radicals, formation of hydroperoxides, which are known to be important intermediates, and decomposition of peroxides leading to the formation of volatile organic species and higher molecular weight compounds. However, critical details have eluded comprehension, such as the emergence of the initial radicals, the detailed mechanistic understanding of important chemical species observed in experiments, or the role of most of the transition metals suspected to induce catalytic enhancement of the oxidation reactions. d2c66b5586