In this work, a novel procedure for fast assessment of the material residual stability is proposed. The method resides in integral isoconversional kinetic analysis of the thermal oxidation of unaged material employing the Berthelot-Hood temperature function. Subsequently, the obtained conversion-independent kinetic parameter D is also employed for samples aged in various regimes. The value of conversion-dependent parameter A for aged samples is calculated from the oxidation onset temperature measured at 5 °C min-1. The residual stabilities are then calculated as a simple ratio of the parameter A of aged material to that of the unaged one. The method has been applied and verified for the samples of low-density polyethylene aged by thermal, radiation and combined ageing. The method can also be employed for high-throughput screening of the effect of various stabilizers and antioxidants in a given organic matrix.
Keywords: Accelerated ageing; Induction period; Residual stability; Thermooxidation.
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