RATE OF FORMATION OF POLYSULFIDES OF 2-BISBENZOTHIAZOLE-2-2'-DISULFIDE IN THE PRESENCE OF SULFUR AND 2-MERCAPTOBENZOTHIAZOLE

2-Bisbenzothiazole-2,2'-disulfide was heated isothermally with and wit hout sulfur at temperatures between 130 and 178 degrees C for various periods of time and the mixture analyzed by high-pressure liquid chrom atography (HPLC). 2-Bisbenzothiazole-2,2'-monosulfide formed rapidly a nd 2-bisbenzothiazole-2,2'-polysulfides after an induction period of a bout 5 min. Polysulfides of higher sulfur rank are formed by the seque ntial addition of sulfur atoms. 2-Mercaptobenzothiazole catalyzes the formation of 2-bisbenzothiazole-2,2'-polysulfides and elimates the ind uction period. Mechanisms for the decomposition of 2-bisbenzothiazole- 2,2'-disulfide and the catalytic role of 2-mercaptobenzothiazole are p roposed. (C) 1995 John Wiley and Sons, Inc.