CHARACTERIZATION BY DYNAMIC THERMAL METHODS OF SOME BIS-AZOPOLYETHERS WITH AN OCTAMETHYLENE SPACER
Journal Title: Analele Universitatii din Bucuresti. Chimie - Year 2011, Vol 20, Issue 1
Abstract
This paper presents the characterization by dynamic thermal methods of some bis-azopolyethers with an octamethylene spacer. For the thermal analysis we used a MOM-Budapest derivatograph which enables the simultaneous recording of the thermogravimetric (TG), derivative thermogravimetric (DTG) and differential thermal (DTA) analyses. The recordings were performed in the air – static conditions, at different heating rates (10, 15, 20 °C/min), whereas the other working parameters remained constant, in order to obtain comparable data. The performed study led to some conclusions on structure – thermostability – degradation mechanism. The kinetic characteristics, correlated with the thermogravimetric ones, illustrate the degradation via successive reactions and the complexity of the second degradation stage, due to the static division of the methylene groups depending on structure and heating rate.
Authors and Affiliations
N. Hurduc, Gabriela Lisa, Silvia Alazaroaie, Natalia Hurduc
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