DIN 53568-2:1978-05

The procedure described is designed to determine the residue on ignition of rubber, rubber mixtures, elastomers and plastics after pretreatment with sulphric acid. It should preferably be adopted in the case of halogenated products, for which the determination of the residue on ignition in accordance with Part 1 is not possible. This test procedure is as a general role not suitable for the preparation of samples for the quantitative determination of metals in halogenated products. The residue on ignition consists of inorganic substances. These substances are no longer present in the residue on ignition in their original form, as a general rule, but may have undergone changes as a consequence of the treatment with sulphuric acid and under the heating conditions.