Injectable bottlebrush triblock copolymer hydrogel crosslinked with ferric ions
Injectable bottlebrush triblock copolymer hydrogel crosslinked with ferric ions
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DOI：
10.1016/j.polymer.2022.124519
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发表时间：
2022-01-06
期刊：
影响因子：
4.6
通讯作者：
Ito, Taichi
中科院分区：
文献类型：
--
作者：
Nakagawa, Yoshiyuki;Oki, Yuichiro;Ito, Taichi
金属离子可交联水凝胶在许多领域有着广泛的应用，但其合理的设计和合成是一个难点。本研究采用原子转移自由基聚合法合成了A嵌段为聚丙烯酸（PAA），B嵌段为聚低聚乙二醇甲醚丙烯酸酯（POEGA）的阿坝瓶刷型三嵌段共聚物。所得到的瓶刷状三嵌段共聚物PAA-POEGA-PAA在相对高的聚合物浓度下显示出低粘度，并且在低于20wt%的水溶液中表现为牛顿流体。在超过重叠浓度后，通过与三价铁离子混合使溶液胶凝。在达到缠结浓度之前，水凝胶的G'在半稀溶液区域急剧增加。由于POEGA嵌段的瓶刷结构的保水性和空间效应，没有发生共聚物的沉淀，但通过PAA嵌段螯合铁离子可以原位快速胶凝。
Metal ionically crosslinkable hydrogels are useful in many fields; however, it is difficult to design and synthesize them rationally. In this study, we synthesized ABA bottlebrush triblock copolymers, whose A block is poly(acrylic acid) (PAA) and B block is poly(oligo (ethylene glycol) methyl ether acrylate) (POEGA), by atom transfer radical polymerization. The obtained bottlebrush triblock copolymers, PAA-POEGA-PAAs, showed low viscosity at relatively high polymer concentrations and behaved as a Newtonian fluid below 20 wt% in aqueous solutions. The solutions were gelled by mixing with ferric ions after exceeding the overlap concentration. The G' of the hydrogels increased sharply at the region of semi-dilute solutions before reaching the entanglement concentration. Thanks to the water-retention and steric effect of the bottlebrush structure of POEGA blocks, precipitation of the copolymers did not occur, but in situ and rapid gelling was possible via chelation of ferric ions by PAA blocks.