Thesis (M.S.)--University of Wisconsin--Madison, 1982. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 120-124).

Thesis (Ph. D.)--University of Wisconsin--Madison, 1982. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 275-285).

Thesis--Wisconsin. / Vita. Includes bibliographical references (leaves 165-169).

Thesis (M.S.)--University of Wisconsin--Madison, 1969. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (Ph.D.)--Kent State University, 2006. / Title from PDF t.p. (viewed Sept. 19, 2006). Advisor: John L. West. Keywords: nematic isotropic interface, liquid crystal colloids, dielectrophoresis, microparticle, drag effect, Raman mapping, IR imaging. Includes bibliographical references (p. 152-164).

Thesis--University of Florida. / Description based on print version record. Typescript. Vita. Includes bibliographical references (leaves 164-166).

Thesis (Ph.D.)--Brown University, 2005. / Vita. Thesis advisor: Humphrey Maris. Includes bibliographical references (leaves 141-145). Also available online.

A basic introduction to liquid crystals and surfactants has been given, along with a description of the main techniques employed in the study of liquid crystals (in particular optical polarising microscopy, differential scanning calorimetry, nuclear magnetic resonance spectroscopy and x-ray diffraction studies). Conventional surfactants comprise a polar head group and a hydrophobic, hydrocarbon chain ie. they are amphiphilic. Because long chains have high melting points the length of the alkyl chain in these compounds is limited to < ca C[18], as long chain surfactants are usually insoluble. Therefore, in this project the alkyl group has been replaced by a long, hydrophobic polydimethylsiloxane chain. Polydimethylsiloxanes are low melting materials (glass transition at ca -120&deg;C) with very flexible chains, hence surfactants based on them might be readily soluble in water. This project involves chemical attachment of amphiphilic mesogens to alpha-SiH terminated siloxanes of varying lengths and the examination of their surfactant properties. The following type of structure was successfully synthesised: CH[3]CH[2]CH[2]CH[2](Si (CH[3]) [2]O)n Si(CH[3])[2] - m where n = integer; m = amphiphilic mesogen. The amphiphilic head groups of these novel surfactants contained the salts of either a mono-, or a dicarboxylic acid. After the synthesis of these surfactants, the liquid crystal and micelle properties of the sodium and calcium salts, were investigated utilising a number of physical techniques eg. optical microscopy and differential scanning calorimetry. Finally, some work on synergism has been described. When different types of surfactants are purposely mixed, what is sought is synergism, the condition when the properties of the mixture are better than those attainable with the individual components by themselves.

Results are presented from a series of simulations undertaken to investigate the effect of adding small spherical particles to a fluid of rods which would otherwise represent a liquid crystalline (LC) substance. Firstly, a bulk mixture of Hard Gaussian Overlap particles with an aspect ratio of 3:1 and hard spheres with diameters equal to the breadth of the rods is simulated at various sphere concentrations. Both mixing-demixing and isotropic-nematic transition are studied using Monte Carlo techniques. Secondly, the effect of adding Lennard-Jones particles to an LC system modelled using the well established Gay-Berne potential is investigated. These rod-sphere mixtures are simulated using both the original set of interaction parameters and a modified version of the rod-sphere potential proposed in this work. The subject of interest is the internal structure of the binary mixture and its dependence on density, temperature, concentration and various parameters characterising the in-termolecular interactions. Both the mixing-demixing behaviour and the transitions between the isotropic and any LC phases have been studied for four systems which differ in the interaction potential between unlike particles. A range of contrasting microphase separated structures including bicontinuous, cubic, and micelle-like arrangement have been observed in bulk. Thirdly, the four types of mixtures previously studied in bulk are subjected to a static magnetic field. A variety of novel phases are observed for the cases of positive and negative anisotropy in the magnetic susceptibility. These include a lamellar structure, in which layers of rods are separated by layers of spheres, and a configuration with a self-assembling hexagonal array of spheres. Finally, two new models are presented to study liquid crystal mixtures in the presence of curved substrates. These are implemented for the cases of convex and concave spherical surfaces. The simulation results obtained in these geometries indicate segregation of spheres at the topological defect of the director field induced by the surface.

In this project a number of synthetic procedures were investigated with a view to preparing a new type of charge transfer polymer system having a structure based on that of side chain liquid crystal polymers, in that the hoped for polymer was composed of charge transfer acceptors connected to a polymer backbone via a flexible alkyl spacer linkage. As part of this work new charge transfer complexes were prepared some of which have shown possible novel properties, such as, co-operative magnetic effects and film forming capabilities. Finally, in order to characterise materials prepared, a Faraday magnetic susceptibility balance and instrumentation for measuring electrical conductivity has been built.