ROOH was a key intermediate compound in oxidation of polymer because it was only source of (OH)-O-center dot radicals. ROOH was believed to be produced by ROO center dot abstraction H-atom from polymer, which is thermodynamically unfavorable, but it may be facilitated due to the high polymer concentration. However, ROOH also could be produced by ROO center dot reaction with HO2 center dot. For examining the formation scheme of ROOH, kinetics and mechanism for the thermal-oxidative degradation of PEO at 473 K in air was investigated by using the experimental and modeling approaches. The contribution of HO2 center dot reaction with ROO center dot to the formation of ROOH was estimated. (C) 2016 Elsevier B. V. All rights reserved.