Fluorescence of molecular probes doped in polymer composites can nondestructively detect mechanical damages of the composites under stress. We have developed a series of novel “turn on” type molecular probes that can be used to quantitatively measure the mechanical stress in real time by fluorescence imaging. Several reaction mechanisms to initiate mechanochemistry that activate fluorescence of the probes under various mechanical damages are being studied. The study includes responses to persistent compression, tensile stretching, and impact indentation. Molecular structures of probes have been specifically designed and engineered with properties that can significantly improve sensitivity of detection for specific polymer matrices of interest. Recently, we have expanded this study to thermal damage probes and developed several probes that can be used to study kinetics of thermal degradation of polymer composites via wide area fluorescence imaging.
- Development of NDE probes for carbon composites (Boeing).
Research Highlight: Contact for detail (jangsh (at) uw.edu)
Examples of developed mechanical damage probes based on aggregation-induced emission
- Z. Shi, J. Davies, S.-H. Jang, W. Kaminsky, and A. K.-Y. Jen, “Aggregation Induced Emission (AIE) of Trifluoromethyl Substituted Distyrylbenzenes”, Chem. Comm. 2012, 48, 7880.
- R. Toivola, Z. Shi, S.-H. Jang, A. K.-Y. Jen, and B. D. Flinn, “Mechanical Damage Detection for Aerospace Composites Using Matrix Resins Functionalized with Fluorescent Probe Molecules”, Proceedings. SAMPE, 2012.
- T. Howie, Z. Shi, S.-H. Jang, A. K.-Y. Jen, “Detection of Thermal Damage of CFRP Composites Using Fluorescent Probes”, Proceedings. SAMPE, 2012.
Current Team Members: Dr. Sei-Hum Jang, Zhengwei Shi, and Jeffrey Yang
Research Collaborators: B. Flinn (UW, MSE)