In recent years, research has expanded the uses of triblock copolymer gels to a wide variety of applications including everything from ceramics processing to regenerative medicine and drug delivery. The research presented in this dissertation focuses on a physically crosslinked, block copolymers gel system in a selective solvent. This system...
Liquid metal melt-lubrication of high-power and high-speed sliding electrical contacts improves electrical current collection and reduces friction. However, armature material loss may cause transition to arcing or plasma contact. Boundary lubrication of the sliding contact with low melting-point alloys can provide comparable improvement in current collection at reduced temperatures. Bismuth,...
The measurement of weak adhesive energies has previously been difficult to obtain. To measure these energies, I designed a technique that uses the combined sensitivities of both a quartz crystal resonator and the inflation of an elastomeric polymer membrane. The surfaces of the quartz crystal and/or the membrane are modified...
The use of composites is increasing as they afford scientists and engineers the ability to combine the advantageous properties of each constituent phase, e.g. metal ductility and ceramic stiffness. With respect to materials design, biomimetics is garnering increasing attention due to the complex, yet efficient, natural microstructures. One such biomimetic,...
The current trend of ceramic nanotechnology has motivated an ever-increasing need to achieve exquisite control over size, shape, and spatial confinement for functional oxide architectures, in an equivalent manner demonstrated for semiconductors. However, the unique nature of ceramics has posed major challenges for most traditional nanofabrication technologies, putting the development...
Metal nanoparticles in polymeric matrices are of particular scientific interest due to their useful ability to self-assemble into complex nanocomposites. Recent examples involve using ultrathin diblock copolymers coupled with metal nanoparticles in the fabrication of novel electronic, magnetic and photonic devices. As this ordering process takes place far from equilibrium...
Two main topics are addressed in this dissertation: (1) adhesion in hydrogels; (2) interfacial interactions between model glassy polymers. A self-assembly technique for the formation of hydrogels from acrylic triblock copolymer solutions was developed, based on vapor phase solvent exchange. Structure formation in the gels was characterized by small angle...
A novel cryogenic variable temperature UHV STM has been constructed and utilized to investigate the dynamical behavior of isolated organic molecules covalently bound to silicon surfaces.
The microscope can be operated from 8-300 K, and exhibits extremely low drift rates. A new design has been implemented for the rails (used...
This dissertation demonstrates how self-assembly can direct nanoscale ordering and optimize electronic properties of organic semiconductors, as well as organic-inorganic hybrids. In excitonic solar cells, controlling the ordering and interfaces between electron-transporting (n-type) and hole-transporting (p-type) domains is crucial. In addressing this challenge, hybrid nanostructures were designed by mineralization of...
The kinetics of nanoscale Cu-rich precipitates of multicomponent concentrated steels has been investigated utilizing primarily APT and supplemented with a synchrotron radiation experiment, first-principles calculations, Thermo-Calc study, and CTEM (at the longest aging time). Results on mechanical properties and microstructure at a greater length scale are also presented. The studied...