No description available.

This work involves the synthesis of two types of electro-optic monomers and their corresponding polymers. The first type of monomers contain the p-oxy-α-cyanocinnamate structure and were synthesized from ω-hydroxyalkoxy-substituted benzaldehydes and methyl cyanoacetate. These ω-hydroxy-α-cyanoester monomers show a high degree of electron delocalization. Copolyesters were synthesized by copolymerization of these monomers with methyl 12-hydroxydodecanoate by the standard two-stage, high-temperature polyesterification procedure. The copolyesters, incorporating dipolar units all pointing in the same direction, are soluble and solution- and melt-processable. Second harmonic generation (SHG) measurements on chloroform solutions of the copolymers showed enhancements of χ² as large as 20 relative to the dipolar monomers. These are the first known readily soluble main chain polymers that exhibit SHG behavior. The second type of monomers were acrylates containing substituted phenyl esters of benzoic acid as mesogenic (pendant) groups. Specifically, the mesogenic group contained an oxy-aryl-carboxy-aryl-carboxy-alkyl structure separated from the acrylate carbon-carbon double bond by a spacer group, which had a carboxyethyl-carboxyhexyl structure. A synthetic route was established by synthesizing a model monomer containing a 2-methylpropyl group as the alkyl group at the end of the mesogenic group. The model monomer was polymerized free radically and the resulting polymer found to possess a smectic liquid crystalline phase that became isotropic at 103° C. With the synthetic route established, an optically active monomer containing a (S)-2-methyl-1-butyl group as the alkyl group at the end of the mesogenic group was synthesized and polymerized. The optically active polymer was already in a smectic liquid crystalline phase at room temperature (≈25° C) and the phase persisted up to 72.6° C. These results indicate that it is possible to design polymers containing thermotropic liquid crystalline phases by fixing low molecular weight liquid crystalline molecules to a polymer main chain.

A dual inclusion strategy for textile polymers has been investigated to increase elastic energy storage capacity of fibers used in high velocity impact applications. Commercial fibers such as Spectra and Dyneema are made from ultra high molecular weight polyethylene (UHMWPE). Dynamic elastic energy of these fibers is still low therefore limiting their wholesale application without a secondary metallic or ceramic component. The idea in this investigation is to develop methodologies so that the elastic energy of polyethylene based fibers can be increased by several folds. This would allow manufacturing of an all-fabric system for high impact applications. The dual inclusion consists of a polymer phase and a nanoscale inorganic phase to polyethylene. The polymer phase was nylon-6 and the inorganic phase was carbon nanotubes (CNTs). Nylon-6 was blended as a minor phase into UHMWPE and was chosen because of its large fracture strain - almost one order higher than that of UHMWPE. On the other hand, CNTs with their very high strength, modulus, and aspect ratio, contributed to sharing of load and sliding of polymer interfaces as they aligned during extrusion and strain hardening processes. A solution spinning process was developed to produce UHMWPE filaments reinforced with CNTs and nylon-6. The procedure involved dispersing of CNTs into paraffin oil through sonication followed by dissolving polymers into paraffin-CNT solution using a homogenizer. The admixture was fed into a single screw extruder for melt mixing and extrusion through an orifice. The extrudate was rinsed via a hexane bath, stabilized through a heater, and then drawn into a filament winder with controlled stretching. In the next step, the as produced filaments were strain-hardened through repeated loading unloading cycles under tension. / Neat and reinforced filaments were characterized through DSC (Differential Scanning Calorimetry), XRD (X-ray Diffraction), Raman Spectroscopy, SEM (Scanning Electron Microscope), and mechanical tests. Phenomenal improvement in properties was found; modulus, strength, fracture strain, and elastic energy increased by 219%, 100%, 107% and 88%, respectively before strain hardening. Once strain hardened the strength, modulus and elastic energy increased by almost one order of magnitude. Source of these improvements were traced to increase in crystallinity and rate of crystallization, formation of microdroplets as a minor phase, sliding between minor and major phases, coating of nanotubes with polymer and alignment of nanotubes. / by Mujibur Rahman Khan. / Thesis (Ph.D.)--Florida Atlantic University, 2010. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2010. Mode of access: World Wide Web.

Doped electrically conductive polymers are one of the critical materials that have allowed the current technological revolution. Essentially all of today's applications of doped conductive polymers involve vinyl-related polymers. While the application of conductive polymers is rapidly increasing, there is need for additional materials with different electrical behaviors. The current focus is on studying condensation polymers that contain a metal atom and the possibility of undergoing entire chain delocalization of electrons. The different series of organometallic condensation polymers were synthesized by employing interfacial polycondensation technique and characterization of these products were carried out using standard techniques like light scattering photometer, fourier transform infrared spectroscopy (FTIR), matrix assisted laser desorption ionization time of flight mass spectroscopy (MALDI TOF MS) and nuclear magnetic resonance spectroscopy (NMR). The electrical measurements were carried out employing Genrad 1650-B impedance spectroscopy. Prior studies conducted in this area have led to the pathway of looking at two aspects; first, surveying 60 metal-containing polymers that can undergo entire chain delocalization studying the effect of different substituents on their electrical properties and secondly, doping selected candidates employing iodine. The products derived from 2-nitro-1,4-phenylenediamine and N-methyl-1,4- pheneylenediamines with titanocene dichloride exhibited about 10 3 to 10 5 fold magnitude increases in the electrical conductivity on doping with iodine, moving it near conductive region. This increase is dependent on the concentration of the iodine and is cyclic. The results support the starting premise that selected metal-containing condensation polymers can be doped to increase their electrical conductivity. / Further investigation is warranted to see if metal-containing condensation polymers can be important materials in the electronic industry. This research sets the stage for studying not only metal-containing polymeric materials but also to investigate the ability to increase the conductivity of other condensation polymers such as nylons and polyesters through doping. / by Amitabh J. Battin. / Thesis (Ph.D.)--Florida Atlantic University, 2009. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2009. Mode of access: World Wide Web.

Yip Hin-lap = 以PEDOT:PSS為本的高份子發光器件中銦的擴散之研究 / 葉軒立. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 113). / Text in English; abstracts in English and Chinese. / Yip Hin-lap = Yi PEDOT:PSS wei ben de gao fen zi fa guang qi jian zhong yin de kuo san zhi yan jiu / Ye Xuanli. / Abstract --- p.ii / 論文摘要 --- p.iv / Acknowledgements --- p.v / Table of Contents --- p.vi / List of Figures --- p.x / List of Tables --- p.xii / Chapter CHAPTER 1 --- INTRODUCTION --- p.1 / Chapter 1.1 --- Overview --- p.1 / Chapter 1.2 --- Conjugated Polymer --- p.3 / Chapter 1.2.1 --- Electronic and Geometric Configuration --- p.3 / Chapter 1.2.2 --- Charge Carriers --- p.7 / Chapter 1.2.3 --- Concept of Doping --- p.9 / Chapter 1.2.4 --- Electrical Conductivity and Charge Transport Mechanisms --- p.15 / Chapter 1.3 --- "Poly(3,4-ethylenedioxythiophene) [PEDOT]" --- p.16 / Chapter 1.4 --- Polymer Light Emitting Diodes --- p.20 / Chapter 1.4.1 --- Device Fabrication --- p.21 / Chapter 1.4.2 --- Material Design and Properties --- p.23 / Chapter 1.4.3 --- Interface and surface of PLED --- p.25 / Chapter 1.5 --- """Chemistry"" and Diffusion at Interface" --- p.27 / Chapter 1.6 --- Surface/Interface Modification with Self-Assembled Monolayers --- p.30 / Chapter 1.7 --- Aims of This Thesis --- p.33 / References --- p.34 / Chapter CHAPTER 2 --- INSTRUMENTATION --- p.38 / Chapter 2.1 --- X-ray Photoelectron Spectroscopy --- p.38 / Chapter 2.1.1 --- Fundamental Theory of XPS --- p.39 / Chapter 2.1.2 --- Qualitative Analysis using XPS --- p.43 / Chapter 2.1.2.1 --- Chemical Shifts --- p.43 / Chapter 2.1.2.2 --- Shake-up satellites --- p.45 / Chapter 2.1.2.3 --- Valence band structure --- p.45 / Chapter 2.1.3 --- Quantitative Analysis Using XPS --- p.46 / Chapter 2.1.4 --- Depth Profiling --- p.47 / Chapter 2.1.4.1 --- Non-Destructive Method Using Angled-Resolved XPS --- p.47 / Chapter 2.1.4.2 --- Destructive Method Using Ion Sputtering --- p.49 / Chapter 2.1.5 --- Instrumental Setup of XPS --- p.49 / Chapter 2.2 --- PLED Fabrication and Characterization System --- p.51 / Chapter 2.3 --- Current-Voltage-Luminescence (I-V-L) Measurement --- p.53 / Chapter 2.4 --- Electrical Measurement --- p.54 / Chapter 2.5 --- Kelvin Probe Measurement --- p.55 / Chapter 2.6 --- pH Measurement --- p.56 / Chapter 2.7 --- Film Thickness Measurement --- p.56 / Chapter 2.8 --- Contact Angle Measurement --- p.57 / References --- p.60 / Chapter CHAPTER 3 --- STABILITY OF PEDOT:PSS/ITO INTERFACE --- p.61 / Chapter 3.1 --- Introduction --- p.61 / Chapter 3.2 --- Sample Preparation --- p.62 / Chapter 3.3 --- Results and Discussion --- p.63 / Chapter 3.3.1 --- XPS of Core levels in PEDOT:PSS --- p.63 / Chapter 3.3.1.1 --- XPS of S 2p Core Level --- p.64 / Chapter 3.3.1.2 --- XPS of O Is Core Level --- p.66 / Chapter 3.3.1.3 --- XPS of C Is Core Level --- p.68 / Chapter 3.3.2 --- Composition Analysis of PEDOT:PSS Films --- p.71 / References --- p.80 / Chapter CHAPTER 4 --- ELECTRICAL AND ELECTRONIC PROPERTIES OF PEDOT:PSS WITH DISSOLUTED INDIUM --- p.81 / Chapter 4.1 --- Introduction --- p.81 / Chapter 4.2 --- Sample Preparation --- p.81 / Chapter 4.2.1 --- Four-Point Probe Measurement --- p.82 / Chapter 4.2.2 --- Current-Voltage Measurement --- p.82 / Chapter 4.2.3 --- Work Function Measurement --- p.83 / Chapter 4.2.4 --- XPS Experiment --- p.83 / Chapter 4.3 --- Results and Discussion --- p.85 / Chapter 4.3.1 --- Electrical Properties of PEDOT:PSS --- p.86 / Chapter 4.3.2 --- Electronic Properties of PEDOT:PSS --- p.89 / References --- p.97 / Chapter CHAPTER 5 --- BLOCKING REACTIONS BETWEEN ITO AND PEDOT:PSS WITH A SELF-ASSEMBLY MONOLAYER --- p.98 / Chapter 5.1 --- Introduction --- p.98 / Chapter 5.2 --- Sample Preparation --- p.99 / Chapter 5.3 --- Result and Discussion --- p.103 / Chapter 5.3.1 --- In Diffusion Blocking Effect by SAM --- p.103 / Chapter 5.3.2 --- PLED Devices Performance --- p.107 / References --- p.113 / Chapter CHAPTER 6 --- CONCLUSION --- p.114 / Chapter CHAPTER 7 --- FURTHER WORKS --- p.116

Ho Ming Kei = 新的有機發光器件的界面研究 / 何銘基. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references. / Text in English; abstracts in English and Chinese. / Ho Ming Kei = Xin de you ji fa guang qi jian de jie mian yan jiu / He Mingji. / Abstract --- p.i / 论文摘要 --- p.iii / Acknowledgements --- p.iv / Table of Contents --- p.v / List of Figures --- p.viii / List of Tables --- p.xiii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Overview --- p.1 / Chapter 1.2 --- Conjugated Polymers --- p.2 / Chapter 1.2.1 --- Electronic and geometric Configuration --- p.2 / Chapter 1.2.2 --- Charge Carries of conjugated polymers --- p.4 / Chapter 1.2.3 --- Polymer Light Emitting Diodes --- p.11 / Chapter 1.2.4 --- Device Fabrication --- p.12 / Chapter 1.2.5 --- Polymeric Luminescent Material Development --- p.18 / Chapter 1.2.6 --- Interface and Surface of PLED --- p.21 / Chapter 1.3 --- Aims of this thesis --- p.22 / References --- p.24 / Chapter Chapter 2 --- Instrumentation --- p.26 / Chapter 2.1 --- X-ray Photoelectron Spectroscopy --- p.26 / Chapter 2.1.1 --- Introduction --- p.26 / Chapter 2.1.2 --- Basic Principles and Theory --- p.28 / Chapter 2.1.3 --- Qualitative Analysis Using XPS --- p.29 / Chapter 2.1.4 --- Angular Effect on XPS --- p.29 / Chapter 2.1.5 --- Chemical Shifts --- p.30 / Chapter 2.1.6 --- Quantitative Analysis using XPS --- p.31 / Chapter 2.1.6.1 --- Survey spectrum --- p.32 / Chapter 2.1.6.2 --- Core level spectrum --- p.32 / Chapter 2.1.6.3 --- Valence band spectrum --- p.33 / Chapter 2.1.7 --- Instrumental Setup for XPS --- p.33 / Chapter 2.2 --- HV physical vapor deposition system with nitrogen glove box --- p.36 / Chapter 2.2.1 --- Nitrogen grove box --- p.38 / Chapter 2.2.2 --- HV physical vapor deposition system --- p.38 / Chapter 2.3 --- L-V-I measurement system --- p.41 / Chapter 2.3.1 --- Keithley 236 source-measure unit --- p.41 / Chapter 2.3.2 --- Photo Research PR-650 photo meter --- p.43 / Chapter 2.3.3 --- Test Environment Chamber --- p.43 / Chapter 2.4 --- a-Step Profilometer --- p.44 / References --- p.45 / Chapter Chapter 3 --- Interface study between MEHPPV: PEG and Aluminum --- p.46 / Chapter 3.1 --- Introduction --- p.46 / Chapter 3.2 --- Sample Preparations --- p.47 / Chapter 3.2.1 --- Si(lll) substrate preparation --- p.47 / Chapter 3.2.2 --- Au sputtering on the clean Si Surface --- p.48 / Chapter 3.2.3 --- Polymer film formation --- p.48 / Chapter 3.3 --- Results and Discussion --- p.49 / Chapter 3.3.1 --- XPS Survey scan ofMEHPPV --- p.51 / Chapter 3.3.2 --- XPS of Cls Core level ofMEHPPV --- p.51 / Chapter 3.3.3 --- XPS ofOls Core level ofMEHPPV --- p.55 / Chapter 3.3.4 --- XPS of A12p Core level ofMEHPPV --- p.59 / Chapter 3.3.5 --- XPS Survey scan of PEG --- p.64 / Chapter 3.3.6 --- XPS of Cls Core level of PEG --- p.64 / Chapter 3.3.7 --- XPS of Ols Core level of PEG --- p.67 / Chapter 3.3.8 --- XPS of A12p Core level of PEG --- p.70 / Chapter 3.3.9 --- XPS survey scan of MEHPPV:PEG(10wt% PEG) --- p.73 / Chapter 3.3.10 --- XPS Cls core level of MEHPPV:PEG(10wt% PEG) --- p.73 / Chapter 3.3.11 --- XPS Ols core level of MEHPPV:PEG(10wt% PEG) --- p.76 / Chapter 3.3.12 --- XPS A1 2p core level of MEHPPV: PEG --- p.80 / Chapter 3.3.13 --- Surface migration of bulk absorbed oxygen --- p.84 / Chapter 3.4 --- Conclusions --- p.84 / Reference --- p.87 / Chapter Chapter 4 --- Efficiency enhancement in polymer light emitting diodes using Crown ether 18-C6 and aluminum cathode --- p.89 / Chapter 4.1 --- Introduction --- p.89 / Chapter 4.2 --- Sample preparation --- p.91 / Chapter 4.2.1 --- The Cleaning of substrate --- p.91 / Chapter 4.2.2 --- PEDOT: PSS film formation --- p.93 / Chapter 4.2.3 --- Emissive polymer layer formation --- p.94 / Chapter 4.2.4 --- Deposition of metal cathode --- p.94 / Chapter 4.2.5 --- Epoxy Encapsulation --- p.95 / Chapter 4.3 --- Results and Discussion --- p.95 / References --- p.101 / Chapter Chapter 5 --- Concluding Remarks and Future Work --- p.102 / Chapter 5.1 --- Concluding Remarks --- p.102 / Chapter 5.2 --- Future Work --- p.103

by Wong Tak Ming. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (leaves 74-77). / Contents --- p.i / Acknowledgments --- p.iii / Abstract --- p.iv / Abbreviations --- p.v / Chapter Chapter 1. --- Introduction / Chapter 1.1. --- General background on conducting polymers and oligomers --- p.1 / Chapter 1.2. --- Conjugated oligomers and polymers --- p.3 / Chapter 1.2.1 --- Theory of conducting polymers / Chapter 1.2.2 --- Oligo- and poly-(p-phenylene)s / Chapter 1.2.3 --- Oligo and poly(phenylenevinylene)s / Chapter 1.2.4 --- Oligo and poly(phenylenethynylene)s / Chapter 1.3. --- Synthesis and solubilization of structurally rigid conjugated oligomers by dendritication --- p.19 / Chapter 1.4. --- Introduction of dendrimer chemistry --- p.20 / Chapter Chapter 2. --- Results and discussion / Chapter 2.1. --- An accelerated approach to the synthesis of oligo(phenylenevinylene)s -preparation of the propagating dimeric unit72 --- p.25 / Chapter 2.2. --- Synthesis of the polyether dendritic fragments --- p.29 / Chapter 2.3. --- Attempted coupling reactions between the polyether dendrimer and the propagating unit72 --- p.32 / Chapter 2.4. --- Synthesis and characterization of dendritic-solubilized oligo-(phenylenethynylene)s (OPE) --- p.34 / Chapter 2.4.1 --- Synthesis of conjugated propagating units / Chapter 2.4.2 --- Characterization of conjugated propagating units / Chapter 2.5. --- Synthesis and characterization of dendritic-solubilized oligo-(phenylenethynylene) fragments dendrimerized at one end --- p.39 / Chapter 2.5.1 --- Synthesis / Chapter 2.5.2 --- Characterization / Chapter 2.6. --- Synthesis and characterization of oligo(phenylenethynylene)s dendrimerized at both ends --- p.43 / Chapter 2.6.1 --- Synthesis / Chapter 2.6.2 --- Purification and characterization / Chapter 2.6.3 --- Solubility and physical appearance / Chapter Chapter 3. --- Summary --- p.49 / Chapter Chapter 4. --- Experimental section --- p.50 / References --- p.74 / List of spectra --- p.78

Not available / text

This work is focused on the electrical characterization of polymer field effect transistors. Conventional method of characterizing organic polymeric semiconductors includes field-effect mobility measurement and optical time-of-flight measurement of drift mobility. In this dissertation we have introduced a new method that combines the advantages of both these methods. It involves the injection of carriers at the source of a transistor using a voltage pulse followed by their subsequent extraction at the drain. The delay between the two events is used to extract the velocity of carriers. The electronic time-of-flight method is a fast, simple and direct method to determine the charge transport properties of the semiconductor. In addition it also presents itself as a source of information for understanding injection into the semiconductor and determining the trap distribution. Theoretical modeling of transport was performed. Simulation was also done to include effect of non-idealities that are forbiddingly difficult to be solved analytically. Time of flight measurements of drift mobility were performed in organic transistors with varying semiconductors and dielectrics. It was observed that the electronic time-of-flight mobility lies in the range of the field-effect mobility. Variation in drift mobility was also observed with the applied pulse voltage. This was explained to be caused due to a combination of the increase in mobility with gate voltage and the increase in drift mobility at high lateral fields. Finally mobility measurements were done on transistors with varying channel length and it was concluded that the mobility increases proportional to the exponential square root of the electric field. Finally a derivation of the pulse voltage method is discussed that involves the use of a small signal electronic impulse instead of a large signal voltage pulse. It was shown that this method could not be used to calculate the drift velocity in a polymer transistor as it is valid only for low conductivity materials whose dielectric relaxation time is lower that the transit time of the carriers injected.

No description available.