Hollow Cholesteric Liquid Crystal Elastomer Fiber with Synergistically Enhanced Resilience and Mechanochromic Sensitivity
writer：Wenwen Wang, Weijie Cheng, Feixia Liu, Kangyu Jia, Huihui Zhan, Chenguang Yang等
keywords：Hollow Fiber; Cholesteric Liquid Crystal Elastomer; Mechanochromic; Resilience; Sensitivity
source：期刊
specific source：Advanced Science
Issue time：2025年
Mechanochromic cholesteric liquid crystal elastomers (CLCE) are
unique anisotropic rubbers with the programmable optical properties in response
to external stimuli, bringing considerable interests in display, sensing and smart
textiles. However, creating mechanochromic CLCE fibers with high sensitivity,
excellent resilience and stable color-changing reversibility is still a
challenge. This work describes mechanochromic CLCE symmetric
hollow fibers with excellent radial helix alignment prepared by solvent
evaporation-induced assembly and template assistance. The cylindrical symmetry
renders the response identical in all directions perpendicular to fiber axis. The
hollow fibers show mechanochromic ability in full visible spectrum, a large
wavelength blueshift of 2.25 nm·%-1 under low strain. Excellent
mechanochromic reversibility of 100 cycles and resilience are both devoted by cross-linking
structure in the wall layer, which also contributes to reversible orientation-recovery
of liquid crystal units during stretching-recovery cycles. Numerical models and
experimental measurements demonstrate the hollow structure enabled fibers to
produce air pressure inside when being stretched, and the fiber wall layer is
subjected to greater stress compared to solid fibers, thus achieving high
mechanochromic sensitivity. In addition, hollow fiber can still change
color when subjected to the expansion stress inside the cavity, and
programmable information display in fabric prolongs its application in intelligent
textiles.