Department of Organic Biomaterials, Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, 12-3-10 Kanda-Surugadai, Chiyoda, Tokyo, 101-0062, Japan.
Macromol Rapid Commun. 2019 Oct;40(20):e1900323. doi: 10.1002/marc.201900323. Epub 2019 Aug 20.
Reversible covalent bonds yield polymeric materials with functional characteristics such as self-healing, shape memory, stress relaxation, and stimuli-responsiveness. Here, photo-reversibly cappable polyrotaxanes are designed and the on-off controlled dissociation of their supramolecular architectures is demonstrated. The polyrotaxanes are synthesized by capping dithiobenzoates at both terminals of polyethylene glycol threaded through multiple α-cyclodextrins. Since dethreading of the α-cyclodextrins is prevented by the dithiobenzoate stoppers, the supramolecular dissociation is induced by their photo-cleavage. Subsequently, the cleaved dithiobenzoates spontaneously re-cap the polyrotaxane terminals in darkness. Thus, the supramolecular dissociation can be modulated by photo-reversible capping of the dithiobenzoate stoppers. These polyrotaxanes with dithiobenzoate stoppers are promising functional materials for photo-controlling physical properties and structures.
可逆共价键赋予聚合物材料具有自修复、形状记忆、应力松弛和刺激响应等功能特性。在这里，设计了光可逆封端的聚轮烷，并证明了它们的超分子结构的开-关控制解离。聚轮烷通过将多个α-环糊精穿过的聚乙二醇的两端封端二硫代苯甲酸酯来合成。由于二硫代苯甲酸酯止动器阻止了α-环糊精的脱螺纹，因此超分子的解离是由其光裂解诱导的。随后，在黑暗中，断裂的二硫代苯甲酸酯自发地重新封闭聚轮烷的末端。因此，超分子的解离可以通过二硫代苯甲酸酯止动器的光可逆封端来调节。这些带有二硫代苯甲酸酯止动器的聚轮烷是用于光控物理性质和结构的有前途的功能材料。
