Thermo-oxidative degradation behavior and tribological mechanism of dipentaerythritol isononanoate under thermal treatment conditions

Purpose This study aims to investigate the thermal behavior and thermo-oxidative degradation of dipentaerythritol isononanoate (DIPE) under atmospheric conditions; analyze the impact of baking time at 240 °C on its thermal, chemical and tribological properties; and improve lubricant science. Design/methodology/approach A multi-technique approach probed DIPE’s thermo-oxidative and tribological behavior: FT-IR/GPC characterized chemical composition (functional groups, molecular weight); PDSC/TGA analyzed thermal properties (oxidation behavior, decomposition); SRV measured tribological performance (friction, wear) and molecular dynamics (LAMMPS-ReaxFF) explored oxidation mechanisms. The Kissinger–Crane method estimated thermo-oxidative degradation kinetics (activation energy, reaction order). Findings The oxidation of DIPE is a first-order reaction, with products having similar structures but different configurations; DIPE heated for a short time has better tribological performance, which may be related to organic acid products; baking time regulates the oxidation activation energy (Ea) through oxygen concentration; and the Kissinger–Crane method can effectively evaluate the thermal stability of ester oils. Originality/value This research systematically studies DIPE’s thermo-oxidative behavior with multi-technique integration; uncovers baking time’s oxidation Ea regulation mechanism via simulations; and introduces the Kissinger–Crane method for ester oil kinetics, guiding lubricant selection and advancing sustainable lubricant science.