May 24, 2017 | No Comments | By Sarah Preis
Congratulations to HEMI Fellows Prof. Vicky Nguyen and Prof. Sung Hoon Kang for receiving funding from the Army Research Office to investigate extreme dissipation behavior of main-chain liquid-crystalline elastomers (LCEs) and structures with Prof. Christopher Yakacki of University of Colorado, Denver.
The research conducted with this funding will answer fundamental questions regarding the processing-structure-property relationships of LCEs. It will enable the design of new elastomeric materials that can paradoxically exhibit the dissipative behavior of a viscous liquid. The superior dissipation behavior of LCEs then will be harnessed to develop new architected cellular structures for energy absorption and control of wave propagation with vastly improved performance compared to current elastomer-based structures. The ability to locally tune and spatially pattern the chemical structure, molecular arrangement, and cellular architecture will provide a large multi-scale design space for optimization of the dissipative properties.
Demonstration of extreme dissipation behavior of LCE from drop test. Comparison of a LCE ball with a rubber ball from a drop test. After being released, 95% of the energy in the LCE ball was dissipated, as measured by the initial drop height compared to the recovered height. A rubber ball keeps bouncing for a while as it has limited energy dissipation capability. (Movie credit: Christopher M. Yakacki and Mohand O. Saed)
Multi-scale material design for extreme dissipation. The polymer chain alignment can be tailored at the nano-scale and arrangement of liquid crystals can be controlled at the micro-scale. Architected LCEs can be designed to create energy trapping and dissipative structures. (Image credit: Christopher M. Yakacki)
