Electrochemical behaviour of RSSR thiuram disulfides

The electrochemical behaviour of tetraalkylthiuram disulfides (RSSR) has be en investigated by using cyclic voltammetry at various scan rates, temperat ures, and for several organic moieties R. The experiments have been run for solutions of RSSR in acetonitrile, and also for solutions of dithiocarbama te salts ( RS-). These experiments show that RSSR is reducible into RSSR-, but this latter is unstable, decomposing into RS- and RS.. Furthermore, RSS R is partly dissociated into 2RS(-), which is also a reducible species. A m odel is proposed, involving two redox couples RS./RS- and RSSR/RSSR-. The c orresponding voltammograms have been simulated and fitted to the experiment al voltammograms at several temperatures. The experimental observation of t he reduction of RS. for tetraisopropylthiuram disulfide solutions supports the proposed model. (C) 1999 Elsevier Science S.A. All rights reserved.