Physical Sciences and Mathematics Commons^™

Synthesis Of Conjugated Polymers From Xanthene And Alkenyl Flanked Diketopyrrolopyrrole Monomers For High-Performance Electronic Applications., Ranganath Wijesinghe Wahalathantrige Don

Theses and Dissertations

In traditional electronics, inorganic materials such as silicon and germanium are used as semiconductors due to their outstanding semiconducting properties. Unfortunately, inorganic materials are rigid due to their high crystalline nature, and processing these materials is complex and expensive. Furthermore, traditional semiconducting materials do not have favorable mechanical properties in applications such as wearable devices and large-area applications with complicated shapes. Conjugated conducting polymers (CCPs) are being explored as alternative materials to conventional semiconductors due to their mechanical properties and high conductivity. CCPs offer properties such as solution and low-temperature processability, flexibility, thermal and optical properties that traditional semiconductors could …

Higher Energy Gap Control Of Fluorescence In Conjugated Polymers, Chien-Hung Chiang

LSU Doctoral Dissertations

Chemo- and biosensors based on fluorescent conjugated polymer benefit from greater detection sensitivity due to amplification of the electronic perturbations produced by analyte binding. This amplification stems from the exciton-transporting properties of conjugated polymers. A conventional design paradigm relies on the analyte binding events which generate sites of lower energy relative to the polymer energy: either fluorescence quenching sites (turn-off sensors) or bathochromically shifted fluorophores (turn-on sensors). In both type sensors, the excitons migrate to the lower-energy site created by analyte binding.

This dissertation primarily focused the investigation of an alternative paradigm when analyte binding creates higher energy gap sites …

Conjugated Polymer-Based Biomaterials Through Controlled Self-Assembly, Megan Twomey

FIU Electronic Theses and Dissertations

Synthetic polymeric materials have gained significant use as biological materials (biomaterials) in biomedical and pharmaceutical applications. As a result, a demand for well-defined polymers with tunable properties has emerged. The synthetic versatility of polymeric biomaterials allows the opportunity to understand the structure-property relationship of materials and their cellular interactions. A novel class of polymeric biomaterials are conjugated polymers (CPs), which possess desirable physicochemical and excellent photophysical properties, including inherent fluorescence. The synthetic versatility of CPs allows easy modification of the conjugated backbone to tune emission and side chain structures to adjust biocompatibility through increased water solubility, controlled biodegradability, and incorporation …

Design And Application Of Organic Electronic Materials: Pendant Tuning In Polymeric And Molecular Systems, Jonathan S. Tinkham

Doctoral Dissertations

Designing and synthesizing materials for use in organic electronic materials requires fine control over their optical and electronic properties. Variations through substitution can be used to tune solubility and electronic properties, but this can result in degradation of other properties. Substitution with orthogonal pendant groups in both molecular and polymeric systems has the potential for allowing tunability while decreasing the perturbation of other desirable properties of the parent system. This idea was explored through experimental and computational work. Computational modelling was used to understand and predict the properties of molecular and polymeric systems to narrow the wide number of choices …

Synthetic Approaches To Flexible Fluorescent Conjugated Polymers, Tereza Vokata

FIU Electronic Theses and Dissertations

Conjugated polymers (CPs) are intrinsically fluorescent materials that have been used for various biological applications including imaging, sensing, and delivery of biologically active substances. The synthetic control over flexibility and biodegradability of these materials aids the understanding of the structure-function relationships among the photophysical properties, the self-assembly behaviors of the corresponding conjugated polymer nanoparticles (CPNs), and the cellular behaviors of CPNs, such as toxicity, cellular uptake mechanisms, and sub-cellular localization patterns.

Synthetic approaches towards two classes of flexible CPs with well-preserved fluorescent properties are described. The synthesis of flexible poly(p-phenylenebutadiynylene)s (PPBs) uses competing Sonogashira and Glaser coupling reactions …

Optimization Of The Optical And Electrochemical Properties Of Donor-Acceptor Copolymers Through Functional Group And Side Chain Modification, Mark J. Seger

Theses and Dissertations--Chemistry

Donor-acceptor copolymers have received a great deal of attention for application as organic semiconductors, in particular as the active layers in low-cost consumer electronics. The functional groups grafted to the polymer backbones generally dictate the molecular orbital energies of the final materials as well as aid in self-assembly. Additionally, the side chains attached to these functional groups not only dictate the solubility of the final materials, but also their morphological characteristics. The bulk of the research presented in this dissertation focuses on the synthesis and structure-property relationships of polymers containing novel acceptor motifs. Chapter 2 focuses on the synthesis of …