Sugawara Akihide, Asoh Taka-Aki, Takashima Yoshinori, Harada Akira, Uyama Hiroshi
Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
Department of Macromolecular Science, Graduate School of Science, Institute for Advanced Co-Creation Studies, and Innovative Catalysis Science Division, Institute for Open and Transdisciplinary Research Initiatives (OTRI), Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan.
ACS Macro Lett. 2021 Jul 20;10(7):971-977. doi: 10.1021/acsmacrolett.1c00357. Epub 2021 Jul 9.
We developed a mechano-responsive hydrogel that is driven by the dissociation of a host-guest complex. The hydrogel comprised a thermoresponsive linear polymer with adamantane as a guest molecule in its side chain and a nonthermoresponsive network structure with β-cyclodextrin as a host molecule. Immobilization of the thermoresponsive polymer in the hydrogel via host-guest interaction resulted in a partial restriction of its phase transition, even above its lower critical solution temperature (LCST). The hydrogel demonstrated a decrease in transmittance when mechanical stress was applied at a temperature above its LCST, indicating that the phase transition of the thermoresponsive polymer was induced by the dissociation of the host-guest complex under mechanical stress. Moreover, this mechano-responsive behavior was repeatable by cooling the hydrogel to redissolve the thermoresponsive polymer. The strategy of the mechano-responsive phase transition will be useful for various applications that demand the control of desired functions by applied stress.
我们开发了一种由主客体复合物解离驱动的机械响应水凝胶。该水凝胶由一种热响应性线性聚合物组成，其侧链含有金刚烷作为客体分子，以及一种以β-环糊精作为主体分子的非热响应网络结构。通过主客体相互作用将热响应性聚合物固定在水凝胶中，即使在其低临界溶液温度（LCST）以上，也会导致其相变受到部分限制。当在高于其LCST的温度下施加机械应力时，水凝胶的透光率降低，这表明热响应性聚合物的相变是由机械应力下主客体复合物的解离诱导的。此外，通过将水凝胶冷却以重新溶解热响应性聚合物，这种机械响应行为是可重复的。机械响应相变策略将有助于各种需要通过施加应力来控制所需功能的应用。
