Thermal and thermo-oxidative degradations of poly block copolymers: a kinetic study

• Published in: Journal of thermal analysis and calorimetry 2013-04, Vol.112 (1), p.375
• Main Authors: Blanco, I, Cicala, G, Latteri, A, Mamo, A, Recca, A
• Format: Article
• Language: English
• Subjects: Block copolymers
• ISSN: 1388-6150
• DOI: 10.1007/s10973-012-2793-5

The thermal degradation of a series of three novel ABA block copolymers of different molar mass ([M.sub.n]), were the block A is a poly(2,6-dimethyl-1,4-phenylene oxide) (PPO), while the block B is a random copoly(aryl ether sulfone) P(ESES-co-EES), was studied in both inert (flowing nitrogen) and oxidative (static air) atmospheres, to investigate the effects of [M.sub.n] of the central block on the thermal stability. Copolymers were synthesized with a two step method: in the first stage, a linking molecule is selectively attached as end group to the P(ESES-co-EES) which reacts in the second step with the phenolic hydroxyl group of PPO. Degradations were carried out into a thermobalance, in the scanning mode, at various heating rates, and the characteristic parameters of thermal stability, namely initial decomposition temperature ([T.sub.i]) and the activation energy ([E.sub.a]) of degradation, of the various copolymers were determined. Both [T.sub.i] and degradation [E.sub.a] values increased exponentially as a function of [M.sub.n] of copolymers. The results were discussed and interpreted.