Chi Zheng, Ma Chenchen, He Ziyuan, Ma Zihan, Chen Xuegang, Huang Zhaoge
Key Laboratory of Rubber-Plastic of Ministry of Education (QUST), School of Polymer Science and Engineering, Qingdao University of Science and Technology, Qingdao 266042, China.
Polymers (Basel). 2022 Jul 13;14(14):2857. doi: 10.3390/polym14142857.
A kind of terpyridine derivative () in which the amino was incorporated by a short alkyl chain was synthesized. Through grafting of terpyridine units into the hydrophilic copolymers of maleic anhydride and acrylic acid via the reaction of the amino groups in and the maleic anhydride units, a series of gelator polymers-, , and -containing different contents of terpyridine units was synthesized. Under coordination of Ni and terpyridine ligands in linear polymers, the supramolecular hydrogels , , and with different cross-linking degrees were prepared. The linear polymers - had a strong absorption peak at about 290 nm in the UV-vis spectra which was attributed to π-π* transition, and there was a new peak at about 335 nm led by the metal-to-ligands charge transfer (MLCT) when coordinated with Ni ions. According to the rheological behaviors, the storage modulus (G') was larger than the loss modulus (G''). These hydrogels showed typical gel-like characteristics when the terpyridine content of the hydrogels exceeded 10%, and the hydrogels showed liquid-like characteristics when the terpyridine content of the hydrogels was less than 7%. The results of the micromorphological investigation of the xerogels from SEM illustrated the metal-terpyridine coordination cross-linking could have an important influence on the microstructures of the resulting hydrogels. Furthermore, these hydrogels based on supramolecular cross-links exhibited reversible solution-gel transition at different environmental temperatures. At the same time, the equilibrium swelling of the supramolecular hydrogels was 8.0-12.3 g/g, which increased with the decrease in the content of the terpyridine units in the resulting hydrogels.
合成了一种通过短烷基链引入氨基的三联吡啶衍生物（）。通过使（）中的氨基与马来酸酐单元反应，将三联吡啶单元接枝到马来酸酐与丙烯酸的亲水性共聚物中，合成了一系列含有不同三联吡啶单元含量的凝胶剂聚合物——、和。在线性聚合物中镍与三联吡啶配体的配位作用下，制备了具有不同交联度的超分子水凝胶、和。线性聚合物——在紫外可见光谱中约290 nm处有一个强吸收峰，这归因于π-π*跃迁，与镍离子配位时，由于金属-配体电荷转移（MLCT）在约335 nm处出现一个新峰。根据流变行为，储能模量（G'）大于损耗模量（G''）。当水凝胶中三联吡啶含量超过10%时，这些水凝胶表现出典型的凝胶状特性，当水凝胶中三联吡啶含量小于7%时，水凝胶表现出液体状特性。扫描电子显微镜对干凝胶的微观形态研究结果表明，金属-三联吡啶配位交联对所得水凝胶的微观结构有重要影响。此外，这些基于超分子交联的水凝胶在不同环境温度下表现出可逆的溶液-凝胶转变。同时，超分子水凝胶的平衡溶胀度为8.0 - 12.3 g/g，其随所得水凝胶中三联吡啶单元含量的降低而增加。
