RM257 consists of photoactive mesogenic end groups. By in situ polymerization of the mesogen, the optical information can be recorded into RM257 thin film. In this study, the RM257 thin films were exposed to a holography irradiation created using an Ar+ laser. The holography patterns have been found to be imprinted into the polymer thin films. The refractive efficiency can be increased when the sample temperature is properly controlled during holography irradiation. The work was started from the use of two beam interferometry, and further to use three beam interference. The molecular arrangement in the resultant polymer film and their function in optical modulation have been studied.

Abstract This research focuses on the morphologies of polymers after the heat treatment, as the different temperature and time. To make a polymeric light emitting device (PLED), the wet procedure is used to composite the organic layer, such as spin coating, and has the very tremendous influence to its efficiency and performance. Thermal annealing plays an important role on it, especially the relationship between the glass transition temperature (Tg) and the boiling temperature of the solvent. In the experiment of wet procedure, we dissolved the green light polymer (PFG) into the chlorobenzene, and the Tg of PFG is about 108¢XC, and the solvent has been boiled at 134¢XC. After spin coating in the glove box, the organic layer became the liquid thin film, and we must bake it to the solid state. It took different morphologies of the polymers by changing the thermal temperature and time. And we can suppose the molecular arrangement from the ultraviolet-visible absorption spectrometry (UV-vis) and photoluminescence spectrometry (PL). Otherwise, we analyzed the surface morphology by using atomic force microscopy (AFM). Though the measurement of X-ray diffraction made the crystallinity of polymers discovered. After all, we prepared ITO(140nm) / PEDOT:PSS(65nm) /PFG(60nm)/ LiF(1nm) / Ca(10nm) / Al(200nm) for the PLED structure. According to the characteristic of the device, we can discuss what happen to the light emitting layer after thermal annealed. In the conclusion, we got the best performance when thermal temperature is nearby or above the Tg with the longer baking time. Respectively, the green light had the maximum luminance at 10.5v of 38710 cd/m2, and the current efficiency was 7.62 cd/A, and power efficiency was 2.66 lm/watt. And we have found higher baking temperature than Tg, as more than 135oC, made the worse performance through the longer time; except the 125oC. A transition thermal temperature, a little higher than Tg, made the performance keep stable after baking for a long time.

<p>The use of degradable biomedical materials has during the past decades indeed modernized medical science, finding applications in e.g. tissue engineering and drug delivery. The key question is to adapt the material with respect to mechanical properties, surface characteristics and degradation profile to suit the specific application. Degradation products are generally considered non-toxic and they are excreted from the human body. However, large amounts of hydroxy acids may induce a pH decrease and a subsequent inflammatory response at the implantation site.</p><p>In this study, macromolecular design and a combination of cross-linking and adjusted hydrophilicity are utilized as tools to control and tailor degradation rate and subsequent release of degradation products from biomedical polyester-ethers. A series of different homo- and copolymers of -caprolactone (CL) and 1,5-dioxepan-2-one (DXO) were synthesized and their hydrolytic degradation was monitored in phosphate buffer solution at pH 7.4 and 37 °C for up to 546 days. The various materials comprised linear DXO/CL triblock and multiblock copolymers, PCL linear homopolymer and porous structure, and random cross-linked homo- and copolymers of CL/DXO using 2,2’-bis-(ε-caprolactone-4-yl) propane (BCP) as a cross-linking agent.</p><p>The results showed that macromolecular engineering and controlled hydrophilicity of cross-linked networks were useful implements for customizing the release rate of acidic degradation products in order to prevent the formation of local acidic environments and thereby reduce the risk of inflammatory responses in the body.</p>

Cotton based highloft nonwovens have been used in consumer goods such as pillows, upholstered furniture and mattresses for years. Cotton provides comfort, soft hand and cost effectiveness to these products. In contrast to its desirable properties, cotton products have a higher proneness to burning and are characterized as highly flammable materials. During the last decade, the fire safety has been an important issue, and there has been increasing focus on approaches to reduce hazardous fire risks and effects. Incorporating flame resistant (FR) chemicals and fibers is one of the most effective methods to improve thermal resistance of cotton to ignition, and provide high degree of flame retardancy performance in the final product. The major aim of using flame retardants is to provide more time for people to escape from fire and reduce death and injuries. Most of the approaches to produce FR cotton based nonwovens are for applications where durability is not important. For some of the applications wash durability is desired and needed. The focus of this research was to develop semi-durable and durable FR treatments for cotton rich nonwovens in an economical way using a binder fiber, going through-air bonding process and treating them with commercially available FR chemicals in the presence of a chemical binder. These FR treated webs have been evaluated for their FR performance before and after washing. Selected FR chemicals and binder types have effect on the wash durability of the produced webs. Selection of appropriate chemicals and binders in the right combination is important so that desired degree of flame resistancy can be achieved. A neural network model was used to understand these effects, so it can help in selecting the best combination for optimum FR performance and reveal the unknown behavior of FR characteristics. Also, importance of FR chemical type, chemical binder type, chemical add on level and binder percentage based on flammability results was revealed through a statistical analysis.

Thesis (Ph. D.)--University of Washington, 2001. / Vita. Includes bibliographical references (leaves 143-148).

Thesis (Ph. D.)--West Virginia University, 2002. / Title from document title page. Document formatted into pages; contains xii, 138 p. : ill. Includes abstract. Includes bibliographical references (p. 111-118).

Thesis (M.S.)--Tennessee Technological University, 2009. / Title from title page screen (viewed on Feb. 10, 2010). Includes bibliographical references.

Thesis (Ph. D.)--Lehigh University, 2003. / Includes vita. Includes bibliographical references (leaves 164-170).

Thesis (Ph. D.)--Hong Kong University of Science and Technology, 2003. / Includes bibliographical references (leaves 308-330). Also available in electronic version. Access restricted to campus users.

Thesis (Ph.D.)--Lehigh University, 2009. / Advisers: Mohamed S. El-Aasser; E. David Sudol.