ISO 11235:2023

This document specifies the methods to be used for the evaluation of sulfenamide accelerators:
—     MBTS: benzothiazyl disulphide;
—     CBS: N-cyclohexylbenzothiazole-2-sulfenamide;
—     TBBS: N-tert-butylbenzothiazole-2-sulfenamide;
—     DIBS: N,N'-diisopropylbenzothiazole-2-sulfenamide;
—     DCBS: N,N'-dicyclohexylbenzothiazole-2-sulfenamide;
—     MBS: N-oxydiethylenebenzothiazole-2-sulfenamide.
NOTE 1        Although MBTS is not a sulfenamide, it is the primary decomposition product of these accelerators and quantitatively determined by the method specified in 5.2.
The analytical methods are applicable for most commercial sulfenamide accelerators:
—     sulfenamides of primary amines (type I);
—     sulfenamides of unhindered secondary amines (type II);
—     sulfenamides of hindered secondary amines (type III).
NOTE 2        Classification and key properties of sulfenamide accelerators are described in Annex A.
The method (5.2) to determine purity by high performance liquid chromatography (HPLC) is the preferred method.