Thesis (M. S.)--Materials Science and Engineering, Georgia Institute of Technology, 2009. / Committee Chair: Rosario Gerhardt; Committee Member: Gleb Yushin; Committee Member: Hamid Garmestani. Part of the SMARTech Electronic Thesis and Dissertation Collection.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references (leaf 96). Also available via the Internet.

Thesis (Master)--İzmir Institute of Technology, İzmir, 2006 / Keywords: polymer composites, Nanoparticles, glass fiber, mechanical properties, thermal properties. Includes bibliographical references (leaves 75-79).

Cheng, Ka Wing = 聚合物太陽能電池的研究 / 鄭家榮. / "December 2010." / Thesis (M.Phil.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 93-96). / Abstracts in English and Chinese. / Cheng, Ka Wing = Ju he wu tai yang neng dian chi de yan jiu / Zheng Jiarong. / Abstract --- p.i / 概要 --- p.iii / Acknowledgements --- p.iv / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- The Rise of Organic Photovoltaics --- p.1 / Chapter 1.2 --- General Review on Organic Photovoltaics --- p.3 / Chapter 1.2.1 --- Physics of Organic Photovoltaics --- p.4 / Chapter 1.2.2 --- Performance Analysis --- p.10 / Chapter 1.2.3 --- Calibration --- p.11 / Chapter 1.2.4 --- Device Architectures --- p.14 / Chapter 1.3 --- Morphology and Performance of Bulk Heterojunction Polymeric Solar Cells --- p.17 / Chapter 1.3.1 --- Choice of Solvent --- p.17 / Chapter 1.3.2 --- Effect of Annealing --- p.18 / Chapter 1.4 --- The Quest of Higher Efficiency --- p.18 / Chapter 1.5 --- Structure of This Thesis --- p.19 / Chapter 2 --- Optical Properties in a Multilayered Solar Cell --- p.21 / Chapter 2.1 --- Introduction --- p.21 / Chapter 2.2 --- Electromagnetic Waves in a Multilayered Thin Film --- p.22 / Chapter 2.3 --- Microcavity Effect --- p.33 / Chapter 2.4 --- Conclusion --- p.34 / Chapter 3 --- Improvement of Solar Cell Efficiency: Result of Simulation --- p.36 / Chapter 3.1 --- Introduction --- p.36 / Chapter 3.2 --- P3HT:PCBM Bulk Heterojunction Solar Cells --- p.36 / Chapter 3.2.1 --- Standard Devices --- p.37 / Chapter 3.2.2 --- Standard Devices with Inserted Silver Layer --- p.39 / Chapter 3.2.3 --- Silver Layer Inserted Devices Without PEDOT:PSS ... --- p.44 / Chapter 3.3 --- MEH-PPV:PCBM Bulk Heterojunction Solar Cells --- p.46 / Chapter 3.3.1 --- Standard Devices --- p.46 / Chapter 3.3.2 --- Standard Devices with Inserted Silver Layer --- p.50 / Chapter 3.3.3 --- Silver Layer Inserted Devices Without PEDOTiPSS . . --- p.52 / Chapter 3.4 --- Discussion --- p.54 / Chapter 3.5 --- Conclusion --- p.56 / Chapter 4 --- Experimental Results --- p.57 / Chapter 4.1 --- Introduction --- p.57 / Chapter 4.2 --- A General Study on Traditionally Structured Solar cell --- p.58 / Chapter 4.2.1 --- Standard Bulk Heterojunction Devices --- p.58 / Chapter 4.2.2 --- Effects of the Metal Electrodes --- p.59 / Chapter 4.2.3 --- Effects of Annealing Time --- p.60 / Chapter 4.3 --- Modified P3HT:PCBM Bulk Heterojunction Solar Cells --- p.61 / Chapter 4.3.1 --- Optimized Standard Devices --- p.61 / Chapter 4.3.2 --- Standard Devices with Inserted Silver Layer --- p.63 / Chapter 4.3.3 --- Silver Inserted Devices Without PEDOTiPSS --- p.64 / Chapter 4.4 --- Discussion --- p.68 / Chapter 4.5 --- Conclusion --- p.71 / Chapter 5 --- Conclusion --- p.73 / Chapter 5.1 --- Suggestion of Future Works --- p.75 / Chapter A --- Simulation Codes --- p.77 / Chapter A.1 --- P3HT:PCBM (1:1) Standard Device --- p.77 / Chapter B --- Instrumentation --- p.87 / Chapter C --- Sample Preparation --- p.90 / Bibliography --- p.93

Polymer organosilicate nanocomposites have attracted significant attention over the last decade due to improved mechanical, thermal, and barrier properties. Several nanocomposite researchers have recognised potential for biomedical applications, however none have conducted biological investigations. In this project, the predicted ability of the organosilicate to enhance biostability, modulate the release of included drugs, and confer biofunctionality and control over the host response, were assessed as the three primary hypotheses. The studies were conducted with the objective being employment as urinary device biomaterials. Of prime importance was that no detrimental change in cytocompatibility was resultant. Biomedical thermoplastic elastomeric polyurethane organosilicate nanocomposites were prepared from poly(ether)urethane of 1000g/mol poly(tetramethylene oxide) polyol, 4,4??? diphenylmethane diisocyanate, and 1,4 butanediol chain extender chemistry, and various organosilicates with loadings from 1w% to 15w%, using a solution casting technique. Initially, partially exfoliated nanocomposites were produced using a commercially available organosilicate, Cloisite?? 30B. These nanocomposites displayed several advantageous properties, namely i) significant anti-bacterial activity, reducing S. epidermidis adherence after 24h to ~20% for a 15w% organosilicate loading, ii) enhanced biostability, with a 15w% organosilicate loading displaying only slight degradation after a 6 week subcutaneous in vivo ovine implantation, and iii) static modulation of model drug release as a factor of drug properties and organosilicate loading. The former was attributed to the Cloisite?? 30B quaternary ammonium compound, while the latter two were likely primarily barrier effect related and due to changes to poly(ether)urethane permeability. Electrostatic and chemical interactivity between drug and organosilicate was also implicated in the observed drug release modulation. Unfortunately, a lack of in vitro cytocompatibility and poor in vivo inflammatory response will limit in vivo use. Utilising bioinert 1-aminoundecanoic acid as an alternative organic modification, cytocompatible intercalated nanocomposites were produced thus likely allowing in vivo nanocomposite use and exploitation of the barrier effect related properties. However, these nanocomposites were not antibacterial. Variation of the organic modification and/or use of co-modification were viable means of modulating host response and biofunctionality, however nanoscale dispersion of co-modified silicate was poor. Use of nanocomposite technology was concluded beneficial to existing biomaterials, and specifically to biomaterial application as urinary catheters / stents.

My research has focussed on the development of a technique to tailor photochromic switching rates by creating a customised local environment for the dye within an otherwise rigid host matrix. Living radical polymerisation offers the potential to design such a system. A living radical initiator based on a spirooxazine compound was used to polymerise a polymer chain of well controlled molecular weight and polydispersity. This technique facilitated the construction of a conjugate with every photochromic moiety convalently attached to a polymer chain with uniform characteristics. The photochromic behaviour of these new polymer-spirooxazine conjugates were investigated in a cross-linked polymer matrix with a Tg of approximately 120??C. It is well known that photochromic switching is susceptible to local environment effects such as rigidity, free volume and polarity.1, 2 The goal of these systems was to create a uniform local environment which would facilitate controlled changes in the photochromic switching rates. The photophysical investigation of these systems demonstrated the success of this technique. The photochromic rates were directly related to the characteristics of the polymer conjugate. It was postulated the conjugates acted as a customised local environment for the photochromic moiety, encapsulating it from the host matrix. Consequently systematic tailoring of the photochromic switching rates was achieved by changes in the characteristics of the attached polymer. To our knowledge this is the first technique to control local environment of a photochromic compound and thus the first example of systematic tuning of photochromic switching rates. Throughout this research, several characteristics of the attached polymer were modified to give a series of rules for the tuning of photochromic switching rates using this technique. The largest variation in switching speed is achieved through variation of Tg. A range of photochromic rates from extremely slow to near solution-like can be easily achieved. The necessary variations in Tg can be achieved easily using living radical polymerisation techniques. The use of different homopolymers, block and random copolymers were all demonstrated successfully in this work. For finer tuning of the photochromic rates, changes in chain length can be used. It was also found the best living radical polymerisation method for this work was ATRP due to the bulky or incompatible halogen which contributed to efficient encapsulation. However this endgroup effect is only important in systems which do not have a low Tg component. The incorporation of such a component overrides all other contributions to the overall behaviour.

Polymer materials are commonly reinforced with organic or inorganic fillers to improve their mechanical properties and to reduce the cost. Such reinforcement strongly depends on the characteristics of fillers (e.g. size, shape, aspect ratio and surface feature) and their dispersion in polymer matrix. The use of inorganic fillers exploits the synergistic effect of high mechanical strength and heat durability of fillers and processing ease of polymers. However, it often causes interfacial incompatibility and an increase in density and a loss of tenacity and opacity. Because layered clays possess rich intercalation chemistry and can be delaminated into disk-like nanopartciles, we investigate the possibility of developing polymer nanocomposites from montmorillonite (MMT). As a result, two nanomaterials, intercalated polyaniline (PANI) nanocomposites and exfoliated PS nanocomposites, have been fabricated via in situ polymerization. Morevoer, experimental work shows that the surface modification of clays and the dispersion of organically modified clays (i.e. organoclays) are crucial to the success of fabricating polymer nanocomposites. Therefore, molecular dynamics (MD) simulations are used to investigate such fundamental aspects on the structure and dynamics of organoclays and the interfacial interactions and structure of diblock copolymer (i.e. PU) nanocomposites. The simulated results are in good agreement with the available experimental data. For organoclays, the results indicate that the alkyl chains exhibit strong layered structures in the interlayer space of clays. Such layering behaviors strongly depend on the chain length and layer charge. More importantly, a pseudo-quadrilayer structure is observed for organoclays modified with dioctadecyldimethyl ammoniums in which the alkyl chains do not lie flat within a single layer but interlace and spread into the adjacent layers. Finally, different orientaion of chain segments is found in the middle and end segments, and within and out of the layer structure. For polyurethane (PU) nanocomposites, van der Waals interaction between apolar alkyl chains and PU soft segments dominates the interactions between organoclay and PU. In addition, hydrogen bonding can form between the siloxane oxygen of clay surface and nitrogen (hard segment) or oxygen (soft segments) of PU. Furthermore, there is no distinct phase-separated structure for PU in the nanocomposites, which is attributed to the results of competitive interactions among PU, alkyl ammonium and clay surface.

Thesis (Ph. D.)--University of Washington, 2001. / Vita. Includes bibliographical references (leaves 162-169).

Thesis (Ph. D.)--Florida State University, 2003. / Advisor: Dr. Chuck Zhang, Florida State University, College of Engineering, Dept. of Industrial Engineering. Title and description from dissertation home page (viewed Apr. 06, 2004). Includes bibliographical references.

Thesis (M.S.)--Florida State University, 2004. / Advisor: Dr. Chuck Zhang, Florida State University, College of Engineering, Dept. of Industrial Engineering. Title and description from dissertation home page (viewed 6/16/04). Includes bibliographical references.