Kinetics of thermal degradation of flame retardant copolyesters containing phosphorus linked pendent groups

The thermal decomposition behaviour of phosphorus-containing copolyesters, were studied using a conventional dynamic thermogravimetric analysis (TG) in a flowing air atmosphere at several heating rates between 10 and 40 degreesC/min. The activation energy was determined by using Kissinger method, Flynn-Wall-Ozawa method and Friedman method. The results for copolyesters with the phosphorus linkage as pendent groups, which were synthesized from the condensation of terephthalic acid (TPA), ethylene glycol(EG) and 9,10-dihydro-10 [2,3-di (hydroxy carbonyl) propyl] 10-phosphaphenanthrene-10-oxide (DDP), were compared with those of poly (ethylene terephthalate) (PET) and copolyesters with phosphorus linkage in the main chain, which were synthesized from TPA, EG and 2-carboxyethyl(phenylphosphinic) acid (CEPP). It is shown that the presence of the bulky pendent phosphorus side group in the copolyester tends to decrease the activation energy for decomposition in air. (C) 2003 Elsevier Science Ltd. All rights reserved.