论文标题
柔软材料的极端韧性机制
An Extreme Toughening Mechanism for Soft Materials
论文作者
论文摘要
柔软而坚韧的材料本质和日常生活无处不在。软材料的断裂韧性与内在断裂能之间的比率定义了其韧性的增强。软材料的韧性增强长期以来一直归因于它们的散装应力拉伸滞后滞后，这是由穆林斯效应和粘弹性等耗散机制引起的。通过实验和理论的结合，我们在这里表明，大量耗散机制显着低估了软材料的韧性增强。我们提出了一种新的机制和扩展法，以说明各种软材料的极端韧性。我们表明，软材材料的韧性依赖于散装歇斯底里的消散，以及由于聚合物链纠缠等机制而引起的近裂缝耗散。与散装的歇斯底里散发不同，近裂耗散不一定会引起大量材料的大压力拉伸滞后。极端的韧性机制可以普遍应用于各种柔软的坚硬材料，范围从双网水凝胶，互穿网状水凝胶，纠缠网状水凝胶和滑环水凝胶到未填充和填充的橡胶。
Soft yet tough materials are ubiquitous in nature and everyday life. The ratio between fracture toughness and intrinsic fracture energy of a soft material defines its toughness enhancement. Soft materials' toughness enhancement has been long attributed to their bulk stress-stretch hysteresis induced by dissipation mechanisms such as Mullins effect and viscoelasticity. With a combination of experiments and theory, here we show that the bulk dissipation mechanisms significantly underestimate the toughness enhancement of soft tough materials. We propose a new mechanism and scaling law to account for the extreme toughening of diverse soft materials. We show that the toughness enhancement of soft materials relies on both bulk hysteric dissipation, and near-crack dissipation due to mechanisms such as polymer-chain entanglement. Unlike the bulk hysteric dissipation, the near-crack dissipation does not necessarily induce large stress-stretch hysteresis of the bulk material. The extreme toughening mechanism can be universally applied to various soft tough materials, ranging from double-network hydrogels, interpenetrating-network hydrogels, entangled-network hydrogels and slide-ring hydrogels, to unfilled and filled rubbers.
