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.