Sprecher
Beschreibung
Flexible sensors require materials that maintain low mechanical hysteresis under cyclic loading to avoid signal drift [1]. Strain-induced crystallization (SIC) has been proven to effectively enhance the toughness of ion gels, but this process inevitably introduces hysteresis [2]. In this study, the kinetics of strain-induced crystallization in tetra-PEG ion gels were controlled by tuning the network strand length. Gels with short strands favor the formation of planar zig-zag crystals, which melted rapidly, whereas gels with long strands promote helix crystals, which melted slowly. In gels dominated by planar zig-zag crystals, rapid crystal melting suppresses bulk energy dissipation while preserving crack-tip toughening, achieving hysteresis below 2% at 1000% strain and a toughness of approximately 7800 J/m². We also establish a linear correlation between mechanical hysteresis and crystallization hysteresis area, providing a quantitative link between crystallization kinetics and macroscopic energy dissipation. These findings demonstrate that controlling crystal melting kinetics is an effective method for achieving both high toughness and low hysteresis in soft materials.
[1] He, J.; Huang, J.; Li, R.; Chen, Z.; Li, Z.; Zhou, R.; Wang, S.; Gao, W.; Guo, C. F.; Pan, C. Sci. Adv. 12, eaea2450 (2026).
[2] Liu, C.; Morimoto, N.; Jiang, L.; Kawahara, S.; Noritomi, T.; Yokoyama, H.; Mayumi, K.; Ito, K. Science, 372, 6546 (2021),