高性能杂化水凝胶的制备及其性能研究（英文）
作者单位：四川大学高分子科学与工程学院高分子材料工程国家重点实验室
会议名称：《中国化学会2017全国高分子学术论文报告会》
会议日期：2017年
学科分类：07[理学] 070304[理学-物理化学(含∶化学物理)] 0703[理学-化学]
关 键 词：hydrogel mechanical toughness multifunctional cross-linker entanglement
摘 要：Introducing both chemical and physical cross-links into a polymer network has emerged as a prevalent strategy to toughen hydrogels. However, most of these hybrid hydrogels are prepared on a multi-step routes with more than one polymer or cross-linker, which is sophisticated and time consuming. Here, we report on a facile fabrication by in-situ polymerizing acrylamide with a single multifunctional cross-linker. Compressive and tensile tests show the resultant hydrogels exhibit superior mechanical toughness. They can be stretched up to 1900% with a maximal fracture stress of nearly 500 kP a and be compressed to 90%. More impressively, the hydrogels can be fully recovered under compression. Rheological measurements suggest the co-existence of physical and chemical cross-links. Finally, an effective energy dissipation mechanism is observed and discussed. We conclude that the reversible physical cross-links originated from entanglement provide a mechanism of energy dissipation while the chemical cross-links ensure the structural integrity, which could be responsible for the improved mechanical properties.