Blanc Baptiste, Zhang Zhenkun, Liu Eric, Zhou Ning, Dellatolas Ippolyti, Aghvami Ali, Yi Hyunmin, Fraden Seth
Department of Physics, Brandeis University, 415 South Street, Waltham, Massachusetts 02454, United States.
Key Laboratory of Functional Polymer Materials of Ministry of Education, Institute of Polymer Chemistry, College of Chemistry, Nankai University, 300071 Tianjin, China.
Langmuir. 2024 Apr 2;40(13):6862-6868. doi: 10.1021/acs.langmuir.3c03784. Epub 2024 Feb 22.
We report on a synthesis protocol, experimental characterization, and theoretical modeling of active pulsatile Belousov-Zhabotinsky (BZ) hydrogels. Our two-step synthesis technique allows independent optimization of the geometry, the chemical, and the mechanical properties of BZ gels. We identify the role of the surrounding medium chemistry and gel radius for the occurrence of BZ gel oscillations, quantified by the Damköhler number, which is the ratio of chemical reaction to diffusion rates. Tuning the BZ gel size to maximize its chemomechanical oscillation amplitude, we find that its oscillatory strain amplitude is limited by the time scale of gel swelling relative to the chemical oscillation period. Our experimental findings are in good agreement with a Vanag-Epstein model of BZ chemistry and a Tanaka Fillmore theory of gel swelling dynamics.
我们报告了活性脉动贝洛索夫-扎博京斯基（BZ）水凝胶的合成方案、实验表征和理论建模。我们的两步合成技术允许独立优化BZ凝胶的几何形状、化学性质和机械性能。我们确定了周围介质化学性质和凝胶半径对BZ凝胶振荡发生的作用，通过达姆科勒数进行量化，达姆科勒数是化学反应速率与扩散速率之比。通过调整BZ凝胶尺寸以最大化其化学机械振荡幅度，我们发现其振荡应变幅度受凝胶溶胀时间尺度相对于化学振荡周期的限制。我们的实验结果与BZ化学的瓦纳格-爱泼斯坦模型以及凝胶溶胀动力学的田中-菲尔莫尔理论高度吻合。
