Evaluation of thermal stability of quinones by thermal analysis techniques

The thermal behavior of quinones, such as 1,4-benzoquinone; 1,2-naphthoquinone; 1,4-naphthoquinone: 9,10-phenanthraquinone and 9,10-anthraquinone, was evaluated by simultaneous thermogravimetry (TG) and differential scanning calorimetry (DSC). Headspace analysis in GC-MS in different temperatures previously identified by TG and DSC was also performed and provided information about thermal behavior of quinones and their degradation products. Results showed that 1,4-benzoquinone, 1,4-naphthoquinone and 9,10-anthraquinone are thermally stable over the range of the temperature evaluated, while 1,2-naphtoquinone and 9,10-phenanthraquinone decompose above 100 degrees C and 215 degrees C, respectively. Overall, results indicate that the molecular structure influences strongly the course of the thermal decomposition of these quinones and it is a determining factor for its thermal stability. (C) 2011 Elsevier B.V. All rights reserved.