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Polymer and Organic Materials Commons™
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Articles 1 - 9 of 9
Full-Text Articles in Polymer and Organic Materials
Resistive Switching Characteristics Of Nanostructured And Solution-Processed Complex Oxide Assemblies, Zimu Zhou
Doctoral Dissertations
Miniaturization of conventional nonvolatile (NVM) memory devices is rapidly approaching the physical limitations of the constituent materials. An emerging random access memory (RAM), nanoscale resistive RAM (RRAM), has the potential to replace conventional nonvolatile memory and could foster novel type of computing due to its fast switching speed, high scalability, and low power consumption. RRAM, or memristors, represent a class of two terminal devices comprising an insulating layer, such as a metal oxide, sandwiched between two terminal electrodes that exhibits two or more distinct resistance states that depend on the history of the applied bias. While the sudden resistance reduction …
Rheological Investigations Of Self-Assembled Block Copolymer Nanocomposites With Complex Architectures, Benjamin Yavitt
Rheological Investigations Of Self-Assembled Block Copolymer Nanocomposites With Complex Architectures, Benjamin Yavitt
Doctoral Dissertations
The self-assembly of block copolymers (BCP) into microphase separated structures is an attractive route to template and assemble functional nanoparticles (NP) into highly ordered nanocomposites and is central to the “bottom up” fabrication of future materials with tunable electronic, optical, magnetic, and mechanical properties. The optimization of the co-assembly requires an understanding of the fundamentals of phase behavior, intermolecular interactions and dynamics of the polymeric structure. Rheology is a novel characterization tool to investigate these processes in such systems that are not accessible by other means. With the combination of X-ray scattering techniques, structure-property relationships are determined as a function …
Synthesis, Characterization And Application Of Block Copolymer And Nanoparticle Composites, Yue Gai
Synthesis, Characterization And Application Of Block Copolymer And Nanoparticle Composites, Yue Gai
Doctoral Dissertations
The “bottom-up” fabrication of functional hybrid material can be achieved by using directed self-assembly of functional nanoparticles (NP) and block copolymers (BCP) as templates. The versatile nanostructures of BCP provide possibilities to precisely control NPs spatial distribution and the resulting hybrid materials exhibit enhanced electrical, mechanical and optical functionalities. Three main topics related to BCP/NP composites are discussed in this dissertation: I) the spatial distribution of large NP in linear BCP; II) the morphology control of BCP templates with new architectures; and III) the magneto-optical properties of hybrid material using magnetic NPs. For well-ordered BCP/NP composite, the ratio of NP …
Nanoscience At Interfaces And Surfaces: From Jamming To Electrode Texturing, Mengmeng Cui
Nanoscience At Interfaces And Surfaces: From Jamming To Electrode Texturing, Mengmeng Cui
Doctoral Dissertations
This dissertation focuses on the nanoparticle self-assembly on the liquid/liquid interface and the nanomaterial modification on surface. The self-assembly of nanoparticles at the liquid/liquid interface was utilized to trap non-equilibrium morphology when the nanoparticles reach jamming state. The dynamics of jammed systems were further studied by X-ray photon correlation spectroscopy. For the surface part, the nanomaterials were modified on the electrodes to improve the performance of microbial electrosynthesis. Also, a novel and simple method was developed to prepare nanomaterials including nanoparticle surfactants and carbon nanotubes (CNTs).
Refractive Index Engineering And Optical Properties Enhancement By Polymer Nanocomposites, Cheng Li
Refractive Index Engineering And Optical Properties Enhancement By Polymer Nanocomposites, Cheng Li
Doctoral Dissertations
The major part of this dissertation discusses the engineering of the refractive index of materials using solution-processable polymer nanocomposites and their applications in building optical components and devices. Three particular polymer nanocomposites have been introduced to achieve materials with tunable refractive indices and enhanced optical properties, which can be used to manipulate the behavior of light or electromagnetic radiations. In the first system, polyhedral oligomeric silsesquioxane (POSS)/polymer nanocomposites are developed. Thin films with tunable, low refractive indicies were fabricated from the composites. The mechanical strength of these films was characterized, and their application in antireflective coatings is discussed. In the …
Controlling The Assembly Of Nanoparticles In Polymer Blends, Kyle C. Bryson
Controlling The Assembly Of Nanoparticles In Polymer Blends, Kyle C. Bryson
Doctoral Dissertations
While many novel methods have been devised for directing the assembly of nanoparticles in block copolymers, the topic has not reached the same level of sophistication for polymer blends. The assembly of particles at the interface between phase-separated domains can serve as a means to compatibilize polymer blends, reducing domain sizes and enhancing interdomain adhesion by impeding coalescence and decreasing interfacial tension. Compatibilization optimizes the performance of blended materials in applications where the properties of both components must be expressed synergistically, such as in plastics requiring both high strength and high toughness and in photovoltaic films. Thus, approaches to robustly …
Functional Nanostructures From Nanoparticle Building Blocks, Jimmy Lawrence
Functional Nanostructures From Nanoparticle Building Blocks, Jimmy Lawrence
Doctoral Dissertations
Advances in the synthetic strategies of engineered nanomaterials, multifunctional molecules and polymers have opened pathways for the development of functional nanomaterials having unique optoelectronic, mechanical, and biological properties. By designing the chemistry of surface ligands, the organic interface of nanoparticles, one can further the versatility and utilization of engineered nanomaterials, opening pathways for breakthroughs in sensing, catalysis, and delivery using nanomaterials. This thesis describes the synthesis and characterization of small molecule and polymer ligand functionalized inorganic nanoparticles (e.g., metal, semiconducting). Embedding specific chemical functionality into the ligand periphery of nanoparticles enables the resulting functional nanoparticles to react selectively …
Wear Resistant Polydopamine/Ptfe Nanoparticle Composite Coating For Dry Lubrication Applications, Samuel George Beckford
Wear Resistant Polydopamine/Ptfe Nanoparticle Composite Coating For Dry Lubrication Applications, Samuel George Beckford
Graduate Theses and Dissertations
This dissertation presents an investigation into the effect of nanoparticle fillers and a polydopamine adhesive primer on the tribological performance of thin PTFE films. The principal objective of this investigation was to reduce wear in PTFE films, an issue which precludes the use of PTFE films in tribological applications requiring high durability. The friction and wear of the composite films were evaluated using a ball-on-flat configuration in linear reciprocating motion. It was found that the use of a polydopamine adhesive primer reduces the wear of PTFE films more than 600 times. X-ray photoelectron spectroscopy (XPS) results show that a tenacious …
Functional Nanocomposites From Self-Assembly Of Block Copolymers With Nanoparticles, Xinyu Wang
Functional Nanocomposites From Self-Assembly Of Block Copolymers With Nanoparticles, Xinyu Wang
Doctoral Dissertations
This dissertation studied the proper distribution and location control of nanoparticles (NPs) within block copolymer (BCP) templates. A facile ligand exchange reaction was introduced for the hydrophilic magnetic NPs (MNPs) that are readily dispersed in polar solvents with outstanding stability. Small molecule ligands were selected to associate strongly with particle surfaces, provide hydrophilic termini for polarity matching with polar solvents, and offer the potential for hydrogen-bonding interactions to facilitate NP incorporation into polymers. Areal ligand densities of NPs indicated a significant increase in the ligand coverage after the exchange reaction. Hydrophilic MNPs were shown to drive the self-assembly of BCPs …