Search for simulants of sulfur mustard through sorption studies in elastomers

With an aim to probe some of the safe and commercially available nonsulfur chemicals as simulants of sulfur mustard for testing of protective materials, the sorption of bis(2‐chloroethyl) ether (2‐CEE), 1,6‐dichlorohexane, bis(4‐chlorobutyl) ether, n‐octane (OCT), dimethyl methylphosphonate, and ethylene glycol through butyl rubber (IIR) and polyisoprene (PI) rubber was studied at 30 ± 2°C using gravimetric method. Among these compounds, sorption of OCT was maximum while bis(4‐chlorobutyl) ether was sorbed least. The sorption of dimethyl methylphosphonate was intermediate between 2‐CEE and 1,6‐dichlorohexane. With the exception of OCT/IIR, OCT/PI, and 2‐CEE/PI, all other simulant/elastomer systems showed non‐Fickian behavior, implying the potential of OCT as a model compound. The diffusivity of OCT was investigated in IIR and PI; the diffusion coefficient values for OCT/IIR and OCT/PI systems differed by one order of magnitude, being 6.95 × 10^?15 m²/s and 3.74 × 10^?14 m²/s, respectively, indicating the relative impermeability of IIR. The magnitude and dynamics of sorption in OCT/IIR as a function of its concentration and the amount of filler were further studied using the automated gravimetric analyzer. Incorporation of carbon black in IIR further reduced the extent of sorption, thereby implying an improvement in barrier performance. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1801–1806, 2007