| This study involves the application of two different step scan Fourier transform infrared (FTIR) methods, fast FTIR imaging and microsecond time resolved FTIR spectroscopy.; First, the noise sources inherent to fast FTIR imaging were critically analyzed with respect to both the individual optical components and the adjustable sets of experimental data, a square root improvement in signal to noise ratio was realized. Additionally, the definition of the limits of detection and quantification were defined.; It was subsequently shown that fast FTIR imaging could be used to monitor dynamic processes in real time, in situ, and that quantitative information could be obtained. This idea was applied to the detailed study of the time and temperature dependence of the diffusion of 5CB liquid crystal into poly(butyl methacrylate). The diffusion process was found to follow anomalous behavior, which was modeled using a linear superposition of Fickian and case II behaviors.; Finally, fast FTIR imaging was shown to be a useful new technique for the study of semicrystalline polymer morphology. Because of the high chemical sensitivity and spatial resolution inherent to this technique, new information can be gained form these systems, such as the distribution of amorphous components and the segregation of species of different molecular weight. In addition, images obtained using polarized light were used to generate dichroic ratio images. The data from these images was shown to provide a rapid method of determining the relative amount of order in these systems.; The second part of this study involves the study of interactions at liquid crystal/polymer alignment layer interfaces. Microsecond time resolved FTIR spectroscopy was used to determine the response of the liquid crystal molecules to alignment layers of different chemical structure. These results were compared with the local dipole moments of the polymer layers calculated using semiempirical molecular orbital calculations. It was found that dipole-dipole forces are the most important forces for the control of alignment at these interfaces. |
