Thermal analysis of azoic dyes: Part I. Non-isothermal decomposition kinetics of [4-(4-chlorobenzyloxy)-3-methylphenyl](p-tolyl)diazene in dynamic air atmosphere

Thermal analysis of [4-(4-chlorobenzyloxy)-3-methylphenyl](p-tolyl)diazene dye, was performed in dynamic air atmosphere. The compound behavior was investigated using TG, DTG, DTA and DSC techniques, under non-isothermal linear regime. Kinetic parameters of the two decomposition steps were evaluated by means of multi-heating rates methods, such as “mode-free” kinetic methods, IKP method, Perez-Maqueda et al. criterion and Master plot procedure. It was shown that the conversion function which describes the process it is not necessary one of the best-fitting functions (when using single-heating rate methods). IKP method can however reduce the possibilities of choosing the true function which can be precisely obtained by applying discrimination methods.