Full metadata
Title
Development of mehanochemically active polymers for early damage detection
Description
Identification of early damage in polymer composite materials is of significant importance so that preventative measures can be taken before the materials reach catastrophic failure. Scientists have been developing damage detection technologies over many years and recently, mechanophore-based polymers, in which mechanical energy is translated to activate a chemical transformation, have received increasing attention. More specifically, the damage can be made detectable by mechanochromic polymers, which provide a visible color change upon the scission of covalent bonds under stress. This dissertation focuses on the study of a novel self-sensing framework for identifying early and in-situ damage by employing unique stress-sensing mechanophores. Two types of mechanophores, cyclobutane and cyclooctane, were utilized, and the former formed from cinnamoyl moeities and the latter formed from anthracene upon photodimerization. The effects on the thermal and mechanical properties with the addition of the cyclobutane-based polymers into epoxy matrices were investigated. The emergence of cracks was detected by fluorescent signals at a strain level right after the yield point of the polymer blends, and the fluorescence intensified with the accumulation of strain. Similar to the mechanism of fluorescence emission from the cleavage of cyclobutane, the cyclooctane moiety generated fluorescent emission with a higher quantum yield upon cleavage. The experimental results also demonstrated the success of employing the cyclooctane type mechanophore as a potential force sensor, as the fluorescence intensification was correlated with the strain increase.
Date Created
2014
Contributors
- Zou, Jin (Author)
- Dai, Lenore L (Thesis advisor)
- Chattopadhyay, Aditi (Thesis advisor)
- Lind, Mary L (Committee member)
- Mu, Bin (Committee member)
- Yu, Hongyu (Committee member)
- Arizona State University (Publisher)
Topical Subject
Resource Type
Extent
xiii, 168 p. : ill. (some col.)
Language
eng
Copyright Statement
In Copyright
Primary Member of
Peer-reviewed
No
Open Access
No
Handle
https://hdl.handle.net/2286/R.I.26843
Statement of Responsibility
by Jin Zou
Description Source
Viewed on January 21, 2015
Level of coding
full
Note
thesis
Partial requirement for: Ph.D., Arizona State University, 2014
bibliography
Includes bibliographical references (p. 124-139)
Field of study: Chemical engineering
System Created
- 2014-12-01 07:02:13
System Modified
- 2021-08-30 01:32:15
- 3 years 2 months ago
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