Abstract:
Chemical warfare agents (CWAs) are amongst the deadliest known chemicals.
Despite international agreements which ban their use, threats posed by CWAs remain
high, especially considering recent global events.1, 2 Although commonly referred to as
poison gases, CWAs are most often liquids, which exhibit degradation half-lives on the
order of days to several weeks, depending on conditions, classifying them as persistent
threats.3 Therefore, following their dispersion, the most likely mode of exposure an
individual will encounter is contact with residual agent on a contaminated surface. To
reduce the risk, this research incorporated novel catalytic additives into commercial
military urethane coatings, thereby imparting continuous self-decontamination to any
paintable surface. An ideal self-decontaminating coating must quickly detoxify harmful
surface residing chemical agents, maintain the integrity of the original surface and be cost
effective. Novel organic and organometallic additives were designed, synthesized and
incorporated into commercial resin systems at low loadings.
Additives selected for the investigation included fullerene, cyclodextrin, and
polyoxometalate compounds. CWA simulants employed in the examination of surface
reactivity included 2-chloroethyl ethyl sulfide, 2-chloroethyl phenyl sulfide, Demeton-S
and Malathion. Upon illumination with visible light, the fullerene containing coatings
exhibited photocatalytic degradation of CWA simulants on the surface, which resulted in
oxidation by-products. Continuously active, catalytic self-decontaminating coating
surfaces with activity against CWA simulants were developed and demonstrated without
significant alterations to the coating’s physical properties.
