We propose a new concept that utilizes the difference in Poisson's ratio between component materials as a strengthening mechanism that increases the effectiveness of the sacrificial bond toughening mechanism in macroscale double-network (Macro-DN) materials. These Macro-DN composites consist of a macroscopic skeleton imbedded within a soft elastic matrix. We varied the Poisson's ratio of the reinforcing skeleton by introducing auxetic or honeycomb functional structures that results in Poisson’s ratio mismatch between the skeleton and matrix. During uniaxial tensile experiments, high strength and toughness were achieved due to two events: (1) multiple internal bond fractures of the skeleton (like sacrificial bonds in classic DN gels) and (2) significant, biaxial deformation of the matrix imposed by the functional skeleton. The Macro-DN composite with auxetic skeleton exhibits up to 4.2 times higher stiffness and 4.4 times higher yield force than the sum of the component materials. The significant improvement in mechanical performance is correlated to the large mismatch in Poisson's ratio between component materials, and the enhancement is especially noticeable in the low-stretch regime. The strengthening mechanism reported here based on Poisson's ratio mismatch can be widely used for soft materials regardless of chemical composition and will improve the mechanical properties of elastomer and hydrogel systems.

我们提出了一个新概念，利用组分材料之间泊松比的差异作为增强机制，提高宏观双网络 (Macro-DN) 材料中牺牲键增韧机制的有效性。这些 Macro-DN 复合材料由嵌入软弹性基质中的宏观骨架组成。我们通过引入拉胀或蜂窝功能结构来改变增强骨架的泊松比，这导致骨架和基质之间的泊松比不匹配。在单轴拉伸实验中，高强度和韧性的实现是由于两个事件：（1）骨架的多次内部键断裂（如经典 DN 凝胶中的牺牲键）和（2）由功能施加的基体的显着双轴变形骨骼。具有拉胀骨架的 Macro-DN 复合材料的刚度和屈服力比组件材料的总和高 4.2 倍，屈服力高 4.4 倍。机械性能的显着改善与组分材料之间泊松比的大不匹配有关，并且在低拉伸状态下增强尤其明显。此处报道的基于泊松比失配的强化机制可广泛用于软材料，无论其化学成分如何，并将提高弹性体和水凝胶系统的机械性能。s 组分材料之间的比率，并且在低拉伸状态下增强尤其明显。此处报道的基于泊松比失配的强化机制可广泛用于软材料，无论其化学成分如何，并将提高弹性体和水凝胶系统的机械性能。s 组分材料之间的比率，并且在低拉伸状态下增强尤其明显。此处报道的基于泊松比失配的强化机制可广泛用于软材料，无论其化学成分如何，并将提高弹性体和水凝胶系统的机械性能。