Polymers and Materials for Antiterrorism and Homeland Defense: An

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Polymers and Materials for Antiterrorism and Homeland Defense: An Overview John G . Reynolds and Glenn E. Lawson 1

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Downloaded by FORDHAM UNIV on November 23, 2012 | http://pubs.acs.org Publication Date: December 31, 2007 | doi: 10.1021/bk-2007-0980.ch001

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Forensic Science Center, Lawrence Livermore National Laboratory, P.O. Box 808, L-178, Livermore, C A 94551 ([email protected]) Chemical/Biological Defense Center, 17320 Dahlgren Road, Building 1480, Code Z21, Naval Surface Warfare Division, Dahlgren, V A 22448-5000 ([email protected])

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Polymers and materials play key roles in national security through detection and decontamination addressing chemical, biological, radiological, nuclear and explosives threats. Proposed detection and decontamination methods utilize polymers and other materials to combat terrorist threats. Because today's detectors are not sufficiently sensitive and selective and decontamination agents are not selective enough for all threats and every scenario, research is being conducted to bridge the scientific and technical gaps. Collected in this volume are papers that elucidate specific efforts in developing new polymers and new materials that can be used as platforms in detectors, as the matrix to incorporate specific detection sites, as recognition elements for detection, as detectors themselves, as decontamination agents and as key components in detection systems. The chapters are divided into the categories of chemical detection, biological detection, and decontamination. Although these groupings are primarily based on the applications, much of the design of the polymers and materials can be broadened into other pertinent detection and decontamination scenarios. A variety of polymeric materials and the methodology to produce them are described. These polymers include cross© 2008 American Chemical Society

In Antiterrorism and Homeland Defense; Reynolds, J., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 2007.

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4 linked divinyl benzene-substituted methacrylate polymers, polycarbosilanes, non-aqueous chemically cross-linked polybutadiene gels, conducting polyaniline nanofibers, organically doped polystyrene and polyvinyltoluene, electroplated polymer cast resins, amphiphilic functionalized norbornene polymers, cross-linked divinyl-benzamide phospholipids, silica and organo-silyl polymers. Other materials include metal chelating complexes, functionalized porous silicon, siloxyl immobilized enzymes with porphyrins, polycarbosilanes, quantum dots and nano-crystalline oxides, dendritic complexing sites, amphiphilic functionalized norbornene polymers, reactive glass surfaces, and self assembled monolayers.

Introduction Since, the tragedy that occurred on September 11, 2001, there have been dramatic increases in research activities to develop chemical and biological detection systems for anti-terrorism and homeland defense. To protect military personnel and the general public, chemical and biological warfare detection systems are rapidly becoming an essential part of the homeland security and defense strategies of the United States. Critical research is being conducted in government, academic, and industrial laboratories. The majority of this research activity has been in the collection, detection and mitigation of chemical, biological, nuclear and explosive (CBNE) materials related to weapons of mass destruction (WMD). The aim of this research is concentrated in two different directions; one is concerned with protection and decontamination on the battlefield, the other, protection within civilian populated centers. Battlefield protection and decontamination encompasses rapid detection, neutralization and removal of chemical and biological agents from military vehicles, equipment, personnel, and facilities (1-3). Protection of civilian centers encompasses rapid detection and removal of chemical and biological agents from public buildings, equipment, and civilians, to concentrations that are lower than those required for military applications. A t this time, new detection systems are necessary because current technology is not sufficient in warning of the presence of such weapons. New mitigation methods are necessary for protecting military personnel and the civilian population from attack, as well as securing facilities from contamination. The chemical warfare agents (Figure 1) of main focus in this book are H D , V X , G B , and G D . H D is a blistering agent that attacks the mucous membranes and is lethal at high doses. V X , G B , and G D are nerve agents that have the

In Antiterrorism and Homeland Defense; Reynolds, J., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 2007.

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4 Figure L Chemical structures of warfare agents sulfur mustard (1), VX (2), GB (3), and GD (4).

ability to stop respiratory and nerve functions, as well as kill in only minutes, even in fairly low concentrations (4, 5). Due to the toxic nature of the chemical warfare agents, compounds used during initial investigations of new materials and sensors are often simulants or surrogates. Simulants mimic one or more of the physical properties (for example, vapor pressure) of a chemical warfare agent and have significantly lesser toxicities than those of the chemical agents. Surrogates are compounds that are similar in chemical structure (i.e., contain common functional groups) to chemical agents and, for this reason, might have significant, albeit lesser, toxicities. For example organophosphorous pesticides are often used as surrogates for the organophosphorus nerve agents. The use of simulants and surrogates makes it possible to more safely study decontamination mechanisms, like oxidation, at pentavalent phosphorus atoms as substitutes for nerve agents. The results of these studies can then be extrapolated to chemical warfare agents. Although, simulants and surrogates can facilitate detoxification and decontamination studies, critical final testing must be performed with actual agents. Such testing is extremely dangerous, time consuming and expensive. Detection and decontamination of biological threat agents is also covered in this book. Biological agents cover a broad range of pathogens that either attack organisms directly or produce large toxins, which also debilitate and kill. Detection and decontamination is often studied using surrogates, as in the case of chemical warfare agents. Table I, shows a partial list of these threats from the Centers for Disease Control and Prevention (

Polymers and Materials for Antiterrorism and Homeland Defense: An

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