ISO 11358-2:2021

INTERNATIONAL ISO
STANDARD 11358-2
Third edition
2021-01
Plastics — Thermogravimetry (TG) of
polymers —
Part 2:
Determination of activation energy
Plastiques — Thermogravimétrie (TG) des polymères —
Partie 2: Détermination de l'énergie d'activation
Reference number
©
ISO 2021
© ISO 2021
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ii © ISO 2021 – All rights reserved

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
5 Apparatus . 2
6 Mass and temperature calibration . 2
6.1 Mass calibration . 2
6.2 Temperature calibration . 2
7 Test specimens. 2
8 Procedure. 3
8.1 General . 3
8.2 Non-oxidative reactions . 3
8.3 Oxidative reactions . 3
9 Expression of results . 3
9.1 Graphical presentation . 3
9.2 Determination of activation energy . 3
10 Precision . 5
11 Test report . 5
Bibliography . 6
Foreword
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iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 61, Plastics, Subcommittee SC 5, Physical-
chemical properties.
This third edition cancels and replaces the second edition (ISO 11358-2:2014), which has been
technically revised.
The main changes compared to the previous edition are as follows:
— the designation of rate of conversion has been changed in order to match that used in ISO 11358-3;
— the purge gas requirements have been changed with a reference to ISO 11358-1.
A list of all parts in the ISO 11358 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
iv © ISO 2021 – All rights reserved

INTERNATIONAL STANDARD ISO 11358-2:2021(E)
Plastics — Thermogravimetry (TG) of polymers —
Part 2:
Determination of activation energy
1 Scope
This document specifies a method for the determination of the activation energy, E , in the Arrhenius
a
formula for the decomposition of polymers using a thermogravimetric technique. The method is
applicable only if the reaction proceeds by a single mechanism. It is applicable to multistage reactions if
they consist of clearly separated single-stage steps.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 1135
...