Although many multi-component polymer systems are well characterised, the surface properties of polymers mixed with low surface energy additives have received little attention. In addition, the new branches of scanning probe microscopy that enable high resolution mapping and modification of surface charge distributions have been infrequently applied to polymer surfaces. The surface segregation of a fluorochemical additive directly from a polypropylene host matrix has been investigated by AFM and other surface analysis techniques. The level of surface enrichment was found to be governed by the temperature and duration of annealing. Further investigation revealed that the speed and extent of surface enrichment of the additive increases with polymer molecular weight. The effect of additive structure on surface segregation has also reported. A method of depositing charge onto polypropylene substrates from a high potential scanning AFM tip was developed. The relation between AFM tip- voltage and the level of charge deposited on the substrate suggested that a localised corona discharge was generated. AFM scanning parameters were found to effect the deposition of charge. The charging behavior of fluorochemical doped polypropylene surfaces was investigated on macroscopic scales using a scanning electrometer probe, and on microscopic scales using EFM. Fluorochemical domains at the surface have been found to preferentially accumulate both positive and negative charge. Surface charge distributions were found to become more uniform during annealing. Sub-micron particle capture by charged surfaces was investigated using EFM. In addition, spatially confined amine beads were deposited onto a patch of localised charge and subsequently functionalised to produce a metallic gold coating.

Thesis (Ph. D.)--University of Texas at Austin, 1999. / Vita. Includes bibliographical references (leaves 115-131). Available also in a digital version from Dissertation Abstracts.

Thesis (Ph.D.)--University of Nebraska-Lincoln, 2009. / Title from title screen (site viewed October 13, 2009). PDF text: xiii, 127, 11 p. : ill. (some col.) ; 6 Mb. UMI publication number: AAT 3352608. Includes bibliographical references. Also available in microfilm and microfiche formats.

No description available.

The purpose of this study was to characterize the micromechanical properties of various structural components in asphalt using Atomic Force Microscopy (AFM). The focus of the study was based on nano-indentation experiments performed within a micro-grid of asphalt phases in order to determine micromechanical properties such as stiffness, adhesion and elastic/plastic behavior. The change in microstructure and micromechanical behavior due to oxidative aging of the asphalt was also a primary focus of the study. The experiment was performed with careful consideration of AFM artifacts, which can occur due to factors such as geometry of the cantilever tip, hysteresis, filtering methods and acoustic vibrations. The materials used in this study included asphalts AAB, AAD and ABD from the Materials Reference Library (MRL) of the Strategic Highway Research Program (SHRP), chosen due to variations in crude source, chemical composition and elemental analysis for each asphalt type. The analysis of nano-indentation creep measurements corresponding to phase-separated regions ultimately revealed heterogeneous domains in asphalt with different mechanical properties, and oxidative aging was found to induce substantial microstructural change within these domains, including variations in phase structure, phase properties and phase distribution. The form and extent of these changes, however, were different for each asphalt studied. Data analysis and information collected during this study were used for comparisons to existing models and asphalt data, which validated results and established correlations to earlier, related studies. From these comparisons, it was found that data parallels followed expected trends; furthermore, analogous interpretations and distinctions were made between results from this study and the micellar and microstructural models of asphalt. This study of micromechanical properties that govern asphalt behavior has yielded information essential to the advancement of hot mix asphalt (HMA) performance, including a new asphalt “weak zone” hypothesis and a foundation of data for implementation into new and existing asphalt models.

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Thesis (M.S.)--Worcester Polytechnic Institute. / Keywords: Bacterial adhesion; ionic strength; polarity; lipopolysaccharides; heterogeneity; elasticity; FJC; steric interactions; AFM. Includes bibliographical references (p. 303-306).

Thesis (Ph. D.)--School of Mechanical Engineering, Georgia Institute of Technology, 2004. Directed by Andrei G. Federov. / Vita. Includes bibliographical references (leaves 155-164).

Thesis (M.S.)--Worcester Polytechnic Institute. / Keywords: Leuconostoc mesenteroides NIRC1542; Atomic Force Microscope; Pseudomonas putida KT2442; Adhesion. Includes bibliographical references (p. 75-83).

No description available.