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Frequency Dependent Electromagnetic Sensing (FDEMS) provides a sensitive, convenient, automated means for monitoring the infiltration, polymerization, and degradation processes in polymeric systems. In situ FDEMS sensing monitored both the Hercules Corporation's 3501-6 epoxy resin system and the Minnesota Mining and Manufacturing Corporation's PR500 epoxy resin system during the Resin Transfer Molding (RTM) infiltration and cure process. FDEMS sensing observed the resin position, viscosity, degree of cure, and the buildup in macroscopic properties such as modulus. Degradation of Nylon-11 in various accelerated aging and operational environments was also monitored by in situ FDEMS sensing. By monitoring the entire polymerization and degradation process, in situ FDEMS sensing was able to provide important real time information about the current physical state of various polymeric materials.

Norbornene anhydride precursors were functionalized with hydrophilic moieties to yield water soluble monomers which were then polymerized without protecting groups. Homopolymer synthesis was accomplished with excellent control over molecular weight and polydispersity using Grubbs' 3rd generation catalyst at ambient temperature and pressure. Molecular weights ranged from 3 to 76 kDa with polydispersity indexes varied from 1.05 to 1.15. Copolymers were made by sequential addition of two functionalized norbornene anhydrides monomers to produce Double Hydrophilic Block Copolymers (DHBCs). All polymers were demonstrated to exist in solution as single solvated chains by dynamic and static light scattering experiments. Superabsorbent gels were prepared from carboxylic acid, amine and hydroxyl functionalized norbornene monomers. Swelling ratios for these gels were studied as a function of crosslink density and aqueous solution pH.

With the miniaturization of devices, block copolymers (BCPs) are emerging as promising candidates for scaffolds and templates in the fabrication of nanoscopic structures. Key to the use of BCPs is control of the orientation and lateral ordering of their microdomains in thin films. An external electric field was previously shown to effectively orient BCP microdomains in a desired direction. However, complete alignment of microdomains in BCP thin films remains a challenge due to achieve due to the preferential interactions of blocks at the interfaces with the electrodes. Here, we demonstrate that lithium-PMMA complexes, formed by adding lithium salts to polystyrene-block-poly(methyl methacrylate) (PS-b-PMMA) copolymer, markedly enhanced alignment of BCP microdomains in thin films under an electric field, mainly by the increased dielectric contrast and mediated surface interactions, which significantly reduced the critical field strength. In addition, formation of lithium-PMMA complexes induces a transition in the reorientation process of lamellar microdomains, from disruption/re-formation to grain rotation. The transition arises in an increase in the segmental interaction parameter, χeffc., of the ion-complexed copolymer, which drives stronger phase segregation. This feature is evidenced by increase of microdomain spacing and ordering, the induced disorder-to-order transition (DOT), and order-to-order (OOT) transitions (sphere-to-cylinder, S-to-C). The increase in χeffc is further confirmed by small-angle neutron scattering (SANS) from the complexed copolymers in the disordered state. Moreover, the temperature dependence of χ effc for the complexed copolymer becomes weaker than that of the neat copolymer. The electric-field-induced sphere-to-cylinder transition in thin films depends on the strength of the interfacial interactions. As a result, a strong preferential interfacial interaction suppresses the transition. However, the formation of ion-complexes enhances the ability of an applied electric field to induce S-to-C transition even on a surface with unbalanced interfacial interactions, providing a simple route to ordered arrays of high aspect ratio cylinders oriented normal to the surface.

Over recent decades, molecular biology has been transformed by the progression towards a more physical understanding of biological macromolecules, such that familiar biochemical behavior can be understood in terms of individual macromolecular structure. Such physical insight now guides modern approaches to biotechnology and fundamental biology. Langevin dynamics simulations offer the opportunity to build upon static structural models by treating macromolecules as dynamic entities. Results will be presented of the application of Langevin dynamics simulations to viral genome packaging and voltage-induced polyelectrolyte translocation. An overview will be given demonstrating how Langevin dynamics, taken together with remarkable experimental efforts, has revealed the central importance of DNA/RNA dynamics in each of these phenomena. Based on the success of these studies, it is suggested that Langevin dynamics, in coordination with experimental efforts, represents a powerful tool for improving the fundamental understanding of various phenomena of biological and biotechnological import.

This dissertation describes computer simulations and theoretical analyses of polymer crystallization and amyloid fibrillization. Langevin Dynamics simulations of polymer chains in dilute solutions suggest that chains are prefolded before crystallization, in contradiction with the traditional view that chain folding occurs only on the growth front. The prefolded chain reveals a thickness plateau in low-temperature region (solving the puzzle of "δL catastrophe"), suggesting that lamellar thickness might be a predetermined equilibrium result. Based on the above prefolding and predetermined thickness concepts, the prefolded chains are then taken as the smallest dynamic units in Monte Carlo simulations, where an anisotropic aggregation model is proposed to study single crystals, shish-kebab crystals, and crystal melting. This model is further extended to amyloid fibrillization. The single crystal study shows a rough-flat-rough habit transition, solving a long-standing puzzle for the existing theories. The lamellar growth rate is confirmed to vary exponentially with temperature and concentration. The shish-kebab study confirms that the distribution of kebab spacings is lognormal. In contrast to Pennings' and Hill's models, a new model is proposed to describe the relation between the spacing and temperature: the logarithm of the spacing growth rate is proportional to the inverse of temperature. The spacing is also found to be proportional to the inverse of polymer concentration. A broad melting transition for shish-kebab crystals is observed in simulations. The melting point is confirmed to be proportional to the square root of heating rate, increase exponentially with crystallization temperature, and increase with the logarithm of crystallization time in sigmoidal fashion. It is proposed that the melting point is related to the lamellar diameter, rather than the lamellar thickness in the traditional view. The seeding phenomenon for amyloid fibrils is reproduced in simulations. It is proposed that nucleation of the amyloid fibril is due to its semi-two-dimensional nature, because a pure one-dimensional growth does not require nucleation and does not exhibit sigmoidal curves. The importance of the second layer of β-sheet is stressed. It is proposed that Ostwald ripening (bigger fibrils grow at the expense of smaller ones) is the dominating mechanism for amyloid fibril growth.

The research presented in this thesis focuses on the development of novel functional hybrid organic-inorganic architectures containing chemically-tethered icosohedral carboranes. The motivation behind this work was to understand and overcome the challenges associated with the incorporation of inorganic boron clusters into a variety of well-defined polymeric architectures. This task was critical for the advancement of scientific understanding, as well as the improvement and implementation of novel hybrid materials towards technological applications. Chapter 1 illustrates some of these potential target applications, and highlights the advantages associated with the utilization of hybrid materials, in particular those containing boron. The synthesis of a novel silyl-protected oxanorbornene imide carborane (SONIC) monomer as well as its copolymerization by ring-opening metathesis polymerization (ROMP) to obtain amphiphilic diblock copolymers is described in Chapter 2. The subsequent functionalization and labeling of the polymers, and their solution behavior have been investigated. Initial biological studies have shown the incorporation of the carborane-containing polymers in carcinoma cells. These findings pave the way for future investigations of these polymeric architectures as delivery agents for boron neutron capture therapy in cancer treatment. The random copolymerization of SONIC and cyclooctene is reported in Chapter 3. Polymers with varying compositions have been obtained and hydrogenated to afford polyethylene-like materials. The structural and thermal properties of these materials have been evaluated and compared to model compounds. Carboranes have also been introduced into conjugated polyaromatic structures as side chains. The synthesis of a polyfluorene monomer having two pendant silylcarborane groups is reported in Chapter 4. The homopolymerization of this monomer, and its copolymerization with 2,7-dibromo-9,9-di-n-hexylfluorene by microwave-assisted nickel(0)-mediated coupling was investigated. The advantage offered by the presence of bulky silylcarborane groups is described. Finally, the versatility of carborane-containing polymers is demonstrated through their utilization as resists for nanoimprint lithography (NIL). A novel silylcarborane-containing acrylate has been synthesized as described in Chapter 5. The utilization of only 10 wt% of the carborane-containing resist lead to a two-fold decrease in etch rate. Excellent image transfer was also observed, allowing for the fabrication of gold interdigitated electrodes. This work provides a new set of tools for the efficacious implementation of NIL.