| 초록 |
Liquid crystalline elastomers (LCEs) are renowned for reversible shape transformation upon application of external stimuli which causes the reduction in order. In the thermotropic LCEs, the shape transformation parallel to the director orientation occurs when heated above Tni. Here, we synthesized a series of surface aligned LCEs by aza-Michael addition between diacrylate functionalized nematic monomers and alkylamine chain extenders followed by photopolymerization. In particular, we used the spacer length of nematic monomers and the type of chain extender as a handle to manipulate actuation temperature of LCEs. Specifically, both Tni and actuation temperature significantly decrease with decreasing methylene spacer from 11 to 3. In addition, the use of co-chain extenders was effective to further lower the actuation temperature. Our simple and efficient strategy to manipulate the actuation properties of the LCEs can advance in developing actuators for soft robots and dynamic surfaces. |
