ISO 11358-2 Plastics - Thermogravimetry (TG) of Polymers - Determination of Activation Energy

EUROLAB, with its state-of-the-art accredited laboratories and expert team, offers precise and rapid testing services within the scope of ISO 11358-2 testing. ISO 11358-2 specifies a method for determining the activation energy in the Arrhenius formula for the decomposition of polymers using a thermogravimetric technique.

The method can only be applied if the reaction proceeds by a single mechanism. It can be applied to multistep reactions if they consist of clearly separated single-step steps.

Test samples are heated at several different heating rates and the change in mass is measured as a function of temperature. Temperatures corresponding to the given degrees of conversion are determined for each heating rate. For a given degree of transformation, the logarithm of the heating rate is plotted against the reciprocal of the absolute temperature, and the activation energy is calculated from the slope of the straight line thus obtained.

To increase the accuracy of the determination, record the mass of an empty crucible subjected to the same test conditions, such as atmosphere, gas flow, and heating rate, used in working with the sample. If mass change occurs during operation with an empty crucible (usually attributed to buoyancy), subtract the curve obtained with the empty crucible from the curve obtained with the test sample to obtain a corrected thermogravimetric curve for the sample. This procedure will be repeated for all heating rates. Corrected curves will be used to analyze the results.

EUROLAB assists manufacturers with ISO 11358-2 test compliance. Our test experts, with their professional working mission and principles, provide you, our manufacturers and suppliers, the best service and controlled testing process in our laboratories. Thanks to these services, businesses receive more effective, high-performance and quality testing services and provide safe, fast and uninterrupted service to their customers.