Das Mahapatra Rita, Imani Kusuma Betha Cahaya, Yoon Jinhwan
Department of Chemistry Education, Graduate Department of Chemical Materials, and Institute for Plastic Information and Energy Materials, Pusan National University, 2 Busandaehak-ro 63 beon-gil, Geumjeong-gu, Busan 46241, Republic of Korea.
ACS Appl Mater Interfaces. 2020 Sep 9;12(36):40786-40793. doi: 10.1021/acsami.0c11167. Epub 2020 Aug 25.
The development of multifunctional hydrogels with high strength and stretchability is one of the most important topics in soft-matter research owing to their potential applications in various fields. In this work, a dual physically cross-linked network was designed for the fabrication of ultrastretchable tough hydrogels. The hydrogels were prepared through polymerization of acrylic acid and acrylamide in the presence of positively charged quaternary poly(ethylene imine) (Q-PEI) and micelle-forming Pluronic F127 diacrylate, thus introducing electrostatic interactions between the positively charged Q-PEI and negatively charged poly(acrylic acid--acrylamide). For further mechanical reinforcement, Ca and Cu ions were introduced into the hydrogel network to construct coordination bonds, significantly enhancing tensile strength as well as stretchability. The hydrogel prepared with Ca ion coordination bonds was found to be stretchable to 108 times its original length and exhibited a maximum toughness of 177 MJ·m, representing one of the most robust systems with both extraordinary toughness and superstretchability prepared to date. The hydrogels also exhibited excellent recovery of dimensions and reproducibility in terms of mechanical properties, providing a promising ultrastretchable soft-matter system with outstanding mechanical strength.
由于多功能水凝胶在各个领域的潜在应用，开发具有高强度和拉伸性的多功能水凝胶是软物质研究中最重要的课题之一。在这项工作中，设计了一种双重物理交联网络用于制备超拉伸韧性水凝胶。通过在带正电荷的季铵化聚乙烯亚胺（Q-PEI）和形成胶束的聚环氧乙烷-聚环氧丙烷-聚环氧乙烷三嵌段共聚物二丙烯酸酯存在下使丙烯酸和丙烯酰胺聚合来制备水凝胶，从而在带正电荷的Q-PEI和带负电荷的聚丙烯酸-丙烯酰胺之间引入静电相互作用。为了进一步增强机械性能，将钙离子和铜离子引入水凝胶网络以构建配位键，显著提高拉伸强度以及拉伸性。发现用钙离子配位键制备的水凝胶可拉伸至其原始长度的108倍，并表现出177 MJ·m的最大韧性，代表了迄今为止制备的具有非凡韧性和超拉伸性的最坚固体系之一。这些水凝胶在尺寸恢复和机械性能的可重复性方面也表现出色，提供了一种具有出色机械强度的有前景的超拉伸软物质体系。
