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The chemical sensing of nerve gas agents has become an increasingly important goal due to the 1995 terrorist attack in a Tokyo subway as well as national security concerns in regard to world affairs. Chemical detection needs to be sensitive and selective while being facile, portable, and timely. In this paper, a sensing approach using a pyrene imine molecule is presented that is fluorimetric in response. The detection of a chloro‐Sarin surrogate is measured at 5 ppmv in less than 1 second and is highly selective towards halogenated organophosphates. The pyrene imine molecule is incorporated into polystyrene films as well as micrometer and sub‐micrometer fibers. Using both a direct drawing approach and electrospinning, micrometer and nanofibers can be easily manufactured. Applications for functional sensing micrometer and nanofibers are envisioned for optical devices and photonics in addition to solution and airflow sensing devices.

Nucleation and growth of holes in free-standing ultrathin (<100 nm) polymer films are examined via optical microscopy in order to gain a better understanding of these phenomena. Hole nucleation is quantified with a free energy barrier based on a simple capillary model. Additionally, holes are found to grow exponentially in accordance with previous studies in the literature. Ultrathin films of polystyrene (between 50 and 100 nm) cast via flow coating are suspended atop lithographically patterned arrays of pillars. The films are then annealed above the glass transition temperature to study the nucleation and growth of holes via optical microscopy. Image analysis is performed to measure the density of nucleated holes as well as hole radius as a function of time. Holes are found to grow exponentially with time in a nonlinear viscoelastic, shear thinning regime under high shear strain. The energy barrier model is applied to the nucleation of holes in free-standing thin films and is found to describe the phenomenon well. This analysis of hole nucleation and growth extends the understanding of ongoing research into suspended fiber formation from the melting of free-standing polymer thin films.