Abstract

Three-network hydrogels have a wide range of applications due to their different network structures and diverse cross-linking methods. In this work, a triple-network hydrogel strategy based on double network coordination and cross-linking is proposed, including gelatin (Gelatin) network, polyacrylamide acrylic acid (PAMAAc) network, and sodium alginate (SA) network. SA and AAc molecular chains contain a large amount of -COO-, which can coordinate with metal ions and generate a large number of dynamic coordination bonds. The hydrogel forms the PAMAAc network through free radical polymerization, and at the same time the interpenetrating cross-linked Gelatin network and SA network are formed through hydrogen bonding. In addition, the addition of metal ions realizes the coordination cross-linking of the double network in the hydrogel. Moreover, the prepared composite hydrogels exhibit good mechanical properties and self-recovery properties. It should be noted that the concentration of different metal ions and the time of coordination and crosslinking will affect the mechanical properties of the hydrogel. The current work provides an idea for preparing a three-network hydrogel with high compressive strength and fast self-recovery.

摘要

三网络水凝胶由于其不同的网络结构和多样的交联方式而具有广泛的应用。在这项工作中，提出了一种基于双网络协调和交联的三网络水凝胶策略，包括明胶（Gelatin）网络、聚丙烯酰胺丙烯酸（PAMAAc）网络和海藻酸钠（SA）网络。SA和AAc分子链中含有大量的-COO-，能与金属离子配位，生成大量动态配位键。水凝胶通过自由基聚合形成PAMAAc网络，同时通过氢键形成互穿的交联明胶网络和SA网络。此外，金属离子的加入实现了水凝胶中双网络的配位交联。而且，制备的复合水凝胶具有良好的力学性能和自恢复性能。需要注意的是，不同金属离子的浓度和配位交联的时间都会影响水凝胶的力学性能。目前的工作为制备具有高抗压强度和快速自恢复的三网状水凝胶提供了思路。