Accession Number:

ADA576080

Title:

Electrospinning Applications in Mechanochemistry and Multi-Functional Hydrogel Materials

Descriptive Note:

Master's thesis

Corporate Author:

ILLINOIS UNIV AT URBANA DEPT OF MATERIALS SCIENCE AND ENGINEERING

Personal Author(s):

Report Date:

2012-01-01

Pagination or Media Count:

72.0

Abstract:

Mechanochemistry is the use of mechanical force to perform chemical reactions and has the potential to bring self-healing functionality to the molecular level. The mechanically induced reactions can become productive when stress-sensitive molecules, or mechanophores, are incorporated into materials. One mechanophore that has been heavily investigated is spiropyran a molecule that exhibits a color change when activated, although large strains are required to achieve this activation in elastomeric materials. In addition to color change, the activation of nonpolar spiropyran also results in the formation of a polar species. Electrospinning, a process used to produce very small fibers, has the potential to be used in a number of applications in mechanochemistry. These very small fibers have been shown to possess high molecular orientation, which is a result of the high longitudinal strains imparted to the fibers during their formation. This thesis investigated if low-strain activation of spiropyran could be achieved with the high degree of molecular orientation in electrospun nanofibers. It was also determined whether the high strains during electrospinning could be used to activate gem-dibromocyclopropane, an irreversible mechanophore. Finally, it was explored if the nonpolar-to-polar transition of spiropyran could be used to induce swelling in hydrogels.

Subject Categories:

  • Polymer Chemistry
  • Test Facilities, Equipment and Methods

Distribution Statement:

APPROVED FOR PUBLIC RELEASE