Thermal degradation of pentaerythritol phosphate alcohol: TG and TG–MS studies

Intumescent material, 2,6,7-trioxa-1-phosphabicyclo-[2,2,2]-octane-4-methanol phosphate (PEPA), is synthesized and characterized using FTIR, 1 HNMR and 13 CNMR. The degradation properties of PEPA are studied by employing TG and TG–MS technique. The activation energies for the degradation process of PEPA are calculated by using TG curves obtained from multiple heating rates (Friedman, Kissinger–Akahira–Sunose and Flynn–Wall–Ozawa methods). The degradation that is occurring in the temperature region 307–366 °C has the highest activation energy. Eventhough the calculated activation energies for the degradation differ depending on the approximation method employed, the trend in variation of activation energy for degradation is similar. Single ion monitoring technique proved the evolution of H 2 O, CO/C 2 H 4 , HCHO, C 2 H 5 OH/HCOOH and trace amounts of C 2 H 7 O 3 P and C 4 H 9 O 4 P from the degrading PEPA. The thermal conductivity and stability of the char formed during the TG analysis are also discussed.