THERMAL AND THERMOOXIDATIVE DEGRADATION OF POLY(TRIMETHYLENE OXIDE) AND ITS COMPLEXES WITH NACNS AND LICLO4

The thermal degradation of poly(trimethylene oxide) (PTMO) shows many features common with its homologue poly(ethylene oxide) (PEO) and its isomer poly(propylene oxide) (PPO), the main degradation processes bei ng accounted for by homolysis of C-O (preferentially) and C-C bonds of the backbone, followed by further reaction of the radicals so formed. Complexation with NaSCN slightly increases the PTMO thermal stability , possibly due to the mildly reducing effect of SCN-, in contrast to t he usual destabilising effect of metal complexation, which makes the C -O bonds of the backbone weaker. On the other hand, the formation of f ormate and eater groups in the PTMO-NaSCN complex in oxidative conditi ons is greatly slowed down in comparison to pure PTMO. The same mechan isms suggested for PEO and PPO complexes is invoked here to explain th e thermo-oxidative stability of PTMO alkaline metal complexes. (C) 199 8 Elsevier Science Limited. All rights reserved.