This document describes two methods for identification of antidegradants (antioxidants, antiozonants and stabilizers) which can be present in raw rubber, unvulcanized compounded rubber, or rubber products, by thin layer chromatography.

Method A is a simplified method that provides for the identification of known materials and can be used to check the presence or absence of a particular antidegradant which is expected to be present.

Method B is a more detailed method that enables a greater degree of separation of the spots to be obtained and therefore can be used to detect and identify an unknown antidegradant.

Antidegradants to which these methods are applicable include phosphited polyalkyl phenols, substituted bisphenols, secondary amines, substituted cresols and substituted p-phenylenediamines. Examination for other types of antidegradants is possible under the same condition when there is a standard chromatogram.