THERMOGRAVIMETRIC ANALYSIS STUDY OF A CYCLIC ORGANO-PHOSPHORUS COMPOUND

Abstract

Four methods were used to study the themdl cyclisation of 2-(2-hydroxyphenyl)-phenyl-phosphonous acid 3, and the results were compared with the thermal decomposition of 9,10-Dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO). The decomposition of DOPO was found to be a simple process composed of at least one stage for which apparent activation energies can be calculated. These investigated methods were those of van Kreve-len, Horowitz-Metzger. Coats-Redfern, and MacCallum-Tanner. These methodologies evaluated the similar apparent activation energies E _a for cyclisation of 3 and for decomposition of DOPO. Moreover, these apparent activation energies for decomposition of DOPO were compared with that calculated by the isothermal method.

Key Words:

• Methodology
• Degradation
• Activation Energy
• 9.10 – Dihydro–9–osea–10– phosphaphenanthrene – 10 – oxide