Evaluation of Transparent Polymers for Chemically Hardened Army Systems

摘要

Polymers being considered for use as transparent armor are evaluated for resistance to degradation in a chemical environment and consequently for their ability to be decontaminated. Immersion of these materials in organic liquids chosen as simulants for the CW agents, as well as the decontaminant DS2, is performed as a preliminary screening. These materials include polycarbonate (PC), four forms of polymethyl methacrylate (PMMA), a developmental polyurethane, and polyetherimide (PEI). Environmental stress crazing and cracking (ESC) tests are also used to determine the chemical resistance of PC. The use of linear elastic fracture mechanics (LEFM) for determining the fracture toughness of several of these transparent polymers is illustrated. The development of a crack propagation study based on LEFM is demonstrated with PEI. Ballistic testing is also reported on to further characterize the mechanical properties of these materials. Keywords: Stress testing; Thermoplastic resins; Crazing; Fracture mechanics; Polycarbonates; Polymethyl methacrylates; Ballistics; Decontamination; Cracking (Fracturing). (mjm)