Skip to Main Content
 

Global Search Box

 
 
 
 

Files

File List


ucin1196088584.pdf (7.88 MB)

ETD Abstract Container

Abstract Header

SMALL-ANGLE SCATTERING FROM NANOCOMPOSITES: ELUCIDATION OF HIERARCHICAL MORPHOLOGY/PROPERTY RELATIONSHIPS

JUSTICE, RYAN SCOTT
http://rave.ohiolink.edu/etdc/view?acc_num=ucin1196088584

Abstract Details

2007, PhD, University of Cincinnati, Engineering : Materials Science.
Loading polymer matrices with nanoscale fillers is widely believed to have the potential to push polymer properties to extreme values. Realization of anticipated properties, however, has proven elusive. Recent nanocomposite research suggests better characterization of the large-scale morphology will provide insight explaining these shortfalls. The chapters in this dissertation present ultra small-angle X-ray scattering (USAXS) as a viable tool for elucidating the hierarchical filler morphology that exists within polymer nanocomposites. In Chapter 1, the relationship between imaging data and scattering data is discussed in the context of filler dispersion, where scattering is presented as a complementary characterization technique that, when combined with microscopy, can reveal significantly more morphological information than possible with either technique independently. Chapter 2 provides the details of both a simplified and a fractal tube form factor for the analysis of tube-like (hollow cylinder) fillers, and the analysis of carbon nanotube-filled bismaleimide composites is presented. In Chapter 3, the fractal tube form factor is also used to augment the analysis of percolative networks in carbon nanofiber-filled epoxy composites. The analysis shows that the morphology resulting in electrical percolation in these systems is much more complicated than more common analysis techniques have shown in the literature. Chapter 4 presents the characterization of a system of colloidal silica/epoxy nanocomposites that shows toughness and modulus improvement without sacrificing the working temperature of the neat resin. USAXS analysis concludes the nanoparticles are individually dispersed up to loadings of 25 wt% with an exclusion zone extending to at least ~10x the particle radius at all loadings. While the exclusion zone is not mechanically significant, the silica particles are shown to be effective in reinforcing hard resins. In Chapter 5, the details of a layered-silicate/epoxy system that is scalable and shows both improved toughness and flexural modulus over the neat resin are documented. The implication from this work is homogeneity in the layered silicate morphology is imperative to have simultaneous improvement of modulus and fracture toughness. However, homogeneity in filler morphology is not exclusive to complete exfoliation of the nanoclay layers.
Dr. Dale Schaefer (Advisor)
177 p.
small-angle scattering; nanocomposites; carbon nanotubes; colloidal silica; layered silcates

Recommended Citations

Citations

  • JUSTICE, R. S. (2007). SMALL-ANGLE SCATTERING FROM NANOCOMPOSITES: ELUCIDATION OF HIERARCHICAL MORPHOLOGY/PROPERTY RELATIONSHIPS [Doctoral dissertation, University of Cincinnati]. OhioLINK Electronic Theses and Dissertations Center. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1196088584

    APA Style (7th edition)

  • JUSTICE, RYAN. SMALL-ANGLE SCATTERING FROM NANOCOMPOSITES: ELUCIDATION OF HIERARCHICAL MORPHOLOGY/PROPERTY RELATIONSHIPS. 2007. University of Cincinnati, Doctoral dissertation. OhioLINK Electronic Theses and Dissertations Center, http://rave.ohiolink.edu/etdc/view?acc_num=ucin1196088584.

    MLA Style (8th edition)

  • JUSTICE, RYAN. "SMALL-ANGLE SCATTERING FROM NANOCOMPOSITES: ELUCIDATION OF HIERARCHICAL MORPHOLOGY/PROPERTY RELATIONSHIPS." Doctoral dissertation, University of Cincinnati, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1196088584

    Chicago Manual of Style (17th edition)

ucin1196088584
984
© 2007, all rights reserved.
This open access ETD is published by University of Cincinnati and OhioLINK.