Date of Award
Spring 2006
Document Type
Dissertation - Restricted
Degree Name
Doctor of Philosophy (PhD)
Department
Chemistry
First Advisor
Hossenlopp, Jeanne M.
Second Advisor
Tran, Chieu
Third Advisor
Haworth, Daniel
Abstract
Hydroxy double salts (HDSs) and layered hydroxy salts (LHSs) are a class of 2-D nanostructured materials with nanometer sized galleries. These compounds exhibit interesting physical properties and have many potential and demonstrated applications in various fields, including: anion separations, drug delivery, environmental water decontamination, catalysis, magnetism, and fire retardancy. These compounds have structural properties that can be utilized as design parameters to fine-tune for improved effectiveness in chosen areas of application. The goal of this work is to explore the various synthetic methods and characterization techniques for HDSs and LHSs that will yield important structural information and corresponding reactivities of these nano materials. With this fundamental insight into structure/reactivity relationships, these compounds can be tailored for specific applications as detailed above. Chapter 1 gives a general introduction of these nanostructured materials and provides a detailed literature review on structurally similar smectite clays. In Chapter 2, preparation and characterization of three model compounds, zinc copper acetate (ZCA), zinc nickel acetate (ZNA), and zinc hydroxy acetate (ZHA) are described. Anionic exchange kinetics were performed using the three model compounds and the results were correlated to their structures and the exchange anion size. The effect of varying the exchange reaction conditions such as temperature, time, and anion concentration on the morphology of the exchange products are discussed. Chapter 3 presents an investigation of the thermal degradation of ZCA, ZNA, and ZHA and highlights the possible catalytic effect that ZnO may have on the ketonization of acetic acid to acetone in the gas phase. The presence of a second metal with Zn is investigated to see if that has an effect on the ZnO crystal growth. Chapter 4 describes the efforts taken to improve the thermal stability and fire retardancy of poly (methyl methacrylate) using copper-containing layered materials. Thermal stability and flammability are evaluated using thermogravimetric analysis and cone calorimetry respectively. Chapter 5 demonstrates the use of the Flynn-Wall-Ozawa (FWO) isoconversional method to estimate the apparent activation energy as a function of conversion fraction for pure polystyrene versus its respective composites containing putative thermal stabilizers. Copper hydroxy dodecyl sulfate is used as a potential fire retardant with poly (vinyl esters) and this work is presented in Chapter 6. The summary of this work and suggested future endeavors are described in Chapter 7.