Structure-Property Relationships of Exchangeable Liquid Crystal ElastomersComprising Dynamic Thiourea Bonds
발표자
()
초록
내용
Liquid crystal elastomers (LCEs) combine both the anisotropic properties of rod-like mesogens and a loosely cross-linked polymer network. Acting together, molecularly aligned LCEs can exhibit unique properties, such as muscle-like contraction along the LC director upon heating above nematic-isotropic temperature. Thus, LCEs have long been recognized as potential candidates for artificial muscles since a theoretical framework by De Gennes.[1] In this study, we synthesized dynamically cross-linked LCEs capable of reprocessing and reprogramming, namely “exchangeable LCEs (xLCEs)”, by incorporating oligo(ether-thiourea) as crosslinkers. In particular, the impact of molecular structure and composition of LCE building blocks on the physical properties of the xLCEs was investigated. A structure-property relationship of xLCEs was developed, which demonstrated an effective modulation in a broad range of actuation temperature (30-90 oC) and actuation strain (20-40%).