The Application of Systems Engineering to Functionalize Fabrics at the Nanoscal

The soldier as a system contains many subsystems including the clothing they wear. Stakeholders have acknowledged the need for protective garments for soldiers that are not confining and provide defense against harmful chemicals. This research identifies an approach using metal-organic frameworks (MOFs) as a specific nanostructure of interest to be attached to fibers, creating a protective suit that is lighter and allows the soldier to move with ease.;A bottom-up design approach was used to satisfy the stakeholder requirements and the reactive dye method (RDM) was developed to provide a generic route to attach nanostructures to the surface of the fabric utilizing cyanuric chloride modified with a thiol. This method successfully bound gold nanoparticles, quantum dots, and the MOF, Cu-BTC, to cotton and nylon fibers. Although Cu-BTC fulfilled the MOF requirement, this particular MOF is unstable in air, and therefore, fails to meet other practical operational requirements.;Thus, cotton fabric functionalized with UiO-66-NH2, a water stable MOF, was investigated in this work. The materials were made by seeding the growth of the MOF on the cotton by first attaching zirconium (Zr) to the surface of the fabric via RDM.;After seeding the fabrics with Zr, the UiO-66-NH2 was grown on the fabric using a hydrothermal method. Several different routes of attaching Zr to cyanuric chloride were examined. Scanning electron microscopy (SEM) and powder X-ray diffraction (PXRD) data are shown to be consistent with UiO-66-NH2, and the fabrics have surfaces areas between 35-246 m2/g depending on the synthetic conditions used to produce the materials. The functionalized cotton reacts with DMNP, a chemical nerve agent simulant, as monitored by UV-Vis. The addition of the MOF to the fibers resulted in reaction rates approximately 20 times faster for DMNP than pure cotton alone.;While RDM and UiO-66-NH2 meet many of the stakeholder requirements, when looking more broadly at the life cycle of the fabrics the production of such a fabric introduces several additional requirements to satisfy production requirements. Therefore an alternative microwave based functionalization of fibers was examined. The fabrics produced using this method performed similarly as the RDM fabrics and could be produced using production scale systems, but the MOF structure was damaged during synthesis.;The results show that a trade space of stakeholder requirements exists and that articulation of systems requirements is required to correctly select an attachment method. Moreover, the results show that definition of the stakeholder needs allows for the development of a clear test and evaluation plan that is consistent with the scientific method. Lastly, the results show that systems engineering can be applied to research programs even at the nanoscale.