Abstract
The development of multi-stimuli-responsive shape memory polymers has received increasing attention because of its scientific and technological significance. In this work, epoxy elastomers with reversible crosslinks are synthesized by polymerizing an anthracene-functionalized epoxy monomer, a diepoxy comonomer, and a dicarboxylic acid curing agent. The synthesized elastomers exhibit active responses to both light and heat enabled by the incorporated anthracene groups. When exposed to 365 nm UV light, additional crosslinking points are created by the photo-induced dimerization of pendant anthracene groups. The formation of the crosslinking points increases modulus and glass transition temperature of the elastomers, allowing for the fixation of a temporary shape at room temperature. The temporary shape remains stable until an external heat stimulus is applied to trigger the scission of the dimerized anthracene, which reduces the modulus and glass transition temperature and allows the elastomers to recover their original shapes. The effects of external stimuli on the thermal and dynamic mechanical properties of the elastomers are investigated experimentally and are correlated with molecular dynamics simulations that reveal the changes of structure and dynamics of the anthracene molecules and flexible chains.
| Original language | English |
|---|---|
| Article number | 20214 |
| Journal | Scientific Reports |
| Volume | 10 |
| Issue number | 1 |
| DOIs | |
| State | Published - Dec 2020 |
Funding
This work was supported by the Air Force Office of Scientific Research (Award FA-9550-12-1-0108). The MD simulations were performed at the National Center for Computational Sciences (NCCS) and used resources of the Oak Ridge Leadership Computing Facility (OLCF) at the ORNL, which is supported by the Office of Science of the U.S. DOE under contract number DE-AC05-00OR22725. The MD simulation works were done at Center for Nanophase Materials Sciences, which is a DOE Office of Science user facility. MG acknowledges financial support from Laboratory Director’s R&D program of Oak Ridge National Laboratory, managed by UT-Battelle, LLC for the US DOE. We also thank the China Scholarship Council (No. 201506600009) for their financial support. Also, some of the research was sponsored by the Critical Materials Institute, an Energy Innovation Hub funded by the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, and Advanced Manufacturing Office, under contract DE-AC05-00OR22725 with UT-Battelle, LLC.
| Funders | Funder number |
|---|---|
| Critical Materials Institute | |
| National Center for Computational Sciences | |
| U.S. Department of Energy | DE-AC05-00OR22725 |
| Air Force Office of Scientific Research | FA-9550-12-1-0108 |
| Office of Science | |
| Office of Energy Efficiency and Renewable Energy | |
| Oak Ridge National Laboratory | |
| UT-Battelle | |
| China Scholarship Council | 201506600009 |