Chiral Liquid Crystals (CLCs) can selectively reflect light of a specific wavelength when the period of its helically twisted structure is appropriately chosen and white light propagates along the helical axis. This phenomenon makes CLCs attractive for reflective-color display, without the needs of backlighting, polarizers, or color filters. Polymer Dispersed Chiral Liquid Crystals (PDCLC) have been developed for reflective switchable, bistable color display. However they suffer from high external driving voltage, low reflectivity, and high cost in pretreatment of the substrates. The key to solve these problems is to understand and control the anchoring behavior of CLC at a polymer surface. This research has two purposes: to develop PDCLC films with high reflectivity and to investigate the factors affecting the anchoring behavior of CLC at the polymer surface of the film. Specifically, commercially available chiral dopant and nematic liquid crystals were carefully chosen to formulate the CLCs reflecting different color. These CLCs are mixed with various acrylate and methacrylate monomers respectively, and UV cured at varied conditions to obtain PDCLC films. The anchoring behavior of these films is characterized using polarized optical microscopy, confocal microscopy, and microscopic-spectrophotometer. The factors influencing the anchoring behavior include chemical structure of the monomers, effective diameter of individual cells in PDCLC, thickness of individual cells in PDCLC, and the pitch of CLC, among which the chemical structure of the monomers is the most important. The PDCLC film made with n-hexyl methacrylate is found to selectively reflect light with the reflectivity larger than that of pure CLC with the same pitch.

In this dissertation molecular dynamics simulations of behavior of polymer liquid crystals (PLC's) under tensile deformation have been performed. PLC's composed of random or block copolymers of rigid and flexible segments have been studies. Systems of fully flexible chains have been simulated for comparison. Stress-strain relations and fracture mechanics have been investigated.

This thesis uses multiscale computational modelling to find the fundamental principles that govern defects forming during the operation of new electro-optical devices and the processing of spider silk fibers. The generalized approach developed in this thesis bridges engineering devices and biological processes based on liquid crystalline materials. / Three types of defects are encountered: inversion walls, lines and points. Inversion wall defects are found in the electro-optical device when a nematic thin film undergoes a temperature-induced surface anchoring transition. Point defects naturally occur in the tubular extrusion duct of spiders, while line defects present close topological connections with point defects and are widespread in many high-performance industrial fibers. Three models are used in this thesis and their usage is dependent on the characteristics of the defects studied. / In the case of inversion wall defects, computational modelling is used to verify, complement and analyze experimental measurements made with fluorescence confocal polarizing microscopy by our collaborator at the Georgia Institute of Technology. The various simulation results agree and explain very well experimental observations and provide a thorough understanding of the wall defects behavior. A computational technique is developed to enable the precise determination of the interaction between the liquid crystal and the device substrate. Understanding the behavior of wall defects and estimating interfacial properties are indispensable to the development and optimization of the electro-optical device as they affect properties like temperature of operation, switching voltages and response time. / Computational modelling is also used to investigate the behavior of nematic point defects confined in cylindrical cavities as observed along spiders' spinning apparatus, and to examined textural connections with other well know structures seen in industrial fibers. The various scenarios investigated include: interactions between point defects, topological transformations between point, line and ring defects as well as interactions between ring defects. The simulation results agree and complement previous investigations but also offer a new fundamental understanding on the nature and stability of defects in cylindrical cavities. Understanding the behavior of nematic point and line defects in cylindrical geometries is important as they play a fundamental role in the processing of natural and industrial high-performance fibers.

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Thesis (Ph.D.)--Tufts University, 2002. / Adviser: Peggy Cebe. Submitted to the Dept. of Physics. Includes bibliographical references. Access restricted to members of the Tufts University community. Also available via the World Wide Web;

Thesis (M.S.)--Rochester Institute of Technology, 1989. / Includes bibliographical references (leaves 131-133).

Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references. Also available via the Internet.

Thesis (M. S.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2010. / Committee Chair: Cressler, John; Committee Member: Laskar, Joy; Committee Member: Papapolymerou, John. Part of the SMARTech Electronic Thesis and Dissertation Collection.

Thesis (Ph.D.)--Kent State University, 2006. / Title from PDF t.p. (viewed Sept. 19, 2006). Advisor: R. S. Prosser. Keywords: membrane, NMR, protein, lovemonkey, lyotropic, liquid crystal, bicelle. Includes bibliographical references (p. 250-256).