(Macromolecules) Enhanced Fatigue Resistance of Liquid Crystal Elastomers Enabled by Dynamic Sacrificial Bonds
writer：Zhu, Y.; Wang, M.; Huang, J.; Mi, H.; Xu, Z.; Wu, F.; Chen, L.*; Yang, H.*; Chen, Y.*
keywords：Liquid Crystal Elastomer
source：期刊
specific source：Macromolecules, 2024, 57, 8329-8337.
Issue time：2024年
Fatigue resistance and elasticity are critical factors in extending the
service life of liquid crystal elastomers (LCEs) and expanding their application fields.
Currently, most of LCE-related studies focus on achieving large reversible
deformations, while research on fatigue-resistant LCE material is relatively limited.
Here, we report a facile strategy to improve the fatigue resistance of LCEs by
introducing partial dynamic sacrificial bonds (tetraarylsuccinonitrile, TASN) into
polymeric matrixes. It is found that increasing the amount of TASN units leads to a
decrease in the LC-to-isotropic phase transition temperature, topology-freezing
transition temperature, and thermal actuation strain, while concurrently resulting in an
increase in elongation at break. Most notably, the LCE-TASN materials exhibit
exceptional fatigue resistance, as evidenced by their ability to withstand 3000 cyclic
stretching with a substantial 100% strain load, and they also demonstrate rapid selfrecovery
in as little as 5 minutes. This remarkable performance is attributed to the
reversible dissociation and recombination of the dynamic central C?C bonds of the
TASN units, a feature not found in conventional LCE materials. The current work
provides insight into the design of fatigue-resistant LCEs, thereby helping to expand
the applications of LCEs.