Abbreviated oxidative induction time method without heating/cooling and gas switching

摘要

The well known standardized procedures of oxidation induction time (OIT) determination incorporate the fast heating of a specimen under nitrogen to the set temperature. After stabilization, the furnace atmosphere is changed to oxygen and from this point on the induction period is recorded. Usually, the differential scanning calorimeter (DSC) heating curves are not being used for further analysis. After the event has occurred, the cell is cooled down to ambient in order to load the next specimen. The new proposed method (SHORT) reduces the usual procedure to the necessary measurement, i.e. the analysis of the specimen under oxygen at the elevated isothermal condition. This method seves the heating and cooling period, leading to a reduction of up to 50 percent of the experimental time. In addition, it is not necessary to change the atmosphere from inert to oxygen. This saves nitrogen, the investment for gas switch equipment and eliminates variations of the OIT values due to a not perfectly well defined start point, i.e. how fast the oxygen concentration is changed.