Synthèse des 2,4,6-tri-substitués-sym-triazines contenant des fragments de phénols stériquement encombrés et leurs application

136 p. ; ill. ; 30 cm
Phenols and s-triazines are two great chemical classes to which 2, 4,6-tri-substituted-sym-triazines belong. They are compounds endowed of antioxidizing and thermo-stabilizing properties, whose one finds applications very varied in the fields as well agronomic, petrochemical that medical. The 2,6-di-tert-butyl-4-methylphenol (BHT) and 2,6- di-tert-butylphenol (2,6-DTBPH) used as raw materials for the synthesise of these molecules, are known to terminate the oxidation radical chains by reacting with peroxyls radicals. Hindered phenolics play an important role when used alone or in synergistic mixtures in very small quantities, they are pound to protect effectively certain polymers from action of light and exhibit good antioxidative properties in stabilization of fuels and lubricants. However, the efficiency of such antioxidants decreases sharply at high temperatures because of their insufficient thermal stability…