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It was once thought either impossible or inefficient to photopolymerize a thickness greater than a thin film because of the optical attenuation of light into the depth of the sample. However, if several considerations are allowed, it is indeed possible. Three particular modifications are essential to enhance light penetration into the depth of the system. An initiator that absorbs in a region of the spectrum where no other components absorb maximizes the incident light intensity for photolysis of the initiator. Concentration and/or molar absorptivity of the initiator lower than typically used in thin films enhance light penetration. Finally, photobleaching initiators exhibit decreased absorbance upon photolysis and thus allow light to penetrate more deeply into the system with time. A need to model these systems is born out of the desirability to use light to initiate polymerizations of all sorts, including thicker systems. In this project, a set of differential equations describing the spatial and temporal evolution of the light intensity gradient, photoinitiator concentration gradient, and the photoinitiation rate profile are developed for a thick polymer system. The generalized model accounts for the consumption of initiator, evolution of the products of photolysis, diffusion of the initiator and photolysis products, and absorbance by all system components. The purpose of these studies was to characterize further these systems so that results accurately capture the photoinitiation process. Several key objectives have been accomplished, including the effects of illumination with polychromatic incident light, various illumination schemes, and verification of the predicative ability of the model. The ultimate goal of this project was two fold; first, to build a tool that models photopolymerization systems well, and second, to develop a means for choosing reaction components for photopolymerization applications. To understand and predict how these systems work contributes significantly to the photopolymerization field because it allows the user to predict system behavior accurately and to choose system components appropriate for a particular application.

The most prevalent polymerization methods are those which fall under the category of thermal polymerizations. The ease of initiation and the abundant knowledge present for these long time standards make implementation straightforward. However in some applications, the drawbacks may be numerous and the use of light induced polymerizations may be advantageous. Because of distinct advantages obtained using photopolymerizations as opposed to the more conventional thermally induced polymerizations science continues to further the knowledge and applications of photopolymers. Structured illumination is one such expansion of photopolymer knowledge and is a method by which variations in light intensity set up differential reaction rates evolving in the migration of monomer. The method can be tailored to produce cured systems with enhanced properties such as the reduction of stress or the control of gloss. Polymerization shrinkage is important for many applications since it leads to residual stresses which can deform a system and undermine its optical or mechanical properties. Also, while photopolymerized coatings are generally high in gloss, it is a characteristic of a polymer system that can have great impact on its function and appearance. Utilizing the simple method of structured illumination, and thereby controlling the coating system for both reductions of stress and gloss, can lead to great advantages for the finished product. This contribution looks at not only producing coatings using the method of structured illumination but also characterizes their properties by standard and unconventional means, alike. Mathematical modeling of the shrinkage, stress and monomer migration is also present in this work.

The seed of Santalum spicatum is rich in a fixed oil (59% by weight), which is characterised by a high percentage of acetylenic, ethylenic ximenynic acid (35% of total fatty acids). A number of important aspects of the seed fixed oil, its composition in developing seeds, its triacylglycerols molecular species in the oil, the nutrition and toxicity of the oil feeding, and the possible bioactivity of ximenynic acid in mice were investigated.The identification of cis and trans isomers of ximenynic acid in the seed oil, and the metabolite of ximenynic acid in mouse liver lipid fractions were achieved using 2-amino-2-methyl-1-propanol to form 2-substituted 4,4-dimethyloxazoline derivatives, which were analysed by gas chromatography with mass spectrometric detection.Changes in proximate and fatty acid composition were investigated in developing seed collected weekly from about seven days after flowering to maturity. It was determined that moisture and carbohydrate contents decreased significantly during the development sequence, while fixed oil content increased from 0.3% to 50% (by weight) with seed development. A corresponding increase in the proportions of both oleic and ximenynic acids occurred suggesting a precursor/product relationship. Mature seed collected from different locations in Western Australia showed minor differences in characteristics and lipid composition, which may have been influenced by geographical origin and harvesting year of samples.The lipid components from the seed oil were separated using thin-layer chromatography and the individual triglyceride bands were characterised by high performance liquid chromatography and gas chromatography using flame ionisation and mass spectrometric detection after removal from the plate. The triximenynin (trisantalbin) band showed no other contaminating fatty acids and was obtained in a relatively pure state.A ++ / nutrition and toxicity study was performed by feeding a semi-synthetic diet containing sandalwood seed oil to a level of 15% of total energy content to a group of mice for one month and another group for two months. The most significant effect of sandalwood seed oil ingestion when compared with a standard lab diet (5% fat, by weight) and a canola oil-enriched diet (15% fat, by weight) was an apparent reduction in body weight gain, which may be the effect of ximenynic acid as a growth retardant. Serum aspartate aminotransferase levels were determined in the mice as an indicator of hepatotoxicity. These levels were higher in mice fed the sandalwood seed oil diet than those fed the standard lab diet, suggesting that ximenynic acid may affect liver-specific enzyme activity. Analysis of the total lipid fatty acids of various tissues and organs of mice showed only a low incorporation of ximenynic acid into the general tissues (0.3-3% by weight), and its absence in the brain.This study suggests a few health benefits from consumption of large quantities of sandalwood seed oil in the diet. These include a low lipid content in blood, heart, muscle, increase in the 16:1/16:0 and 18:1/18:0 ratios, production of increased levels of 18:1 (n-9) and docosahexaenoic acid, and decreased levels of arachidonic acid in certain tissues. There were no specific pathological, morphological or mortality changes observed in the mice.Sandalwood seed may be both a food and a medicine.

Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.

Thesis (Ph. D.)--Rutgers University, 2009. / "Graduate Program in Chemical and Biochemical Engineering." Includes bibliographical references (p. 73-78).

Thesis (Ph. D.)--University of Hong Kong, 2009. / Includes bibliographical references (leaves 149-163). Also available in print.

Thesis (Ph.D.)--University of Delaware, 2009. / Principal faculty advisor: Brian J. Bahnson, Dept. of Chemistry & Biochemistry. Includes bibliographical references.

Thesis (M.S.)--West Virginia University, 2001. / Title from document title page. Document formatted into pages; contains vi, 57 p. : ill. Includes abstract. Includes bibliographical references.

published_or_final_version / Biological Sciences / Master / Master of Philosophy