Qiao Haiyan, Wu Baohu, Sun Shengtong, Wu Peiyi
State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Chemistry and Chemical Engineering & Center for Advanced Low-dimension Materials, Donghua University, Shanghai 201620, China.
Jülich Centre for Neutron Science (JCNS) at Heinz Maier-Leibnitz Zentrum (MLZ) Forschungszentrum Jülich, Garching 85748, Germany.
J Am Chem Soc. 2024 Mar 20;146(11):7533-7542. doi: 10.1021/jacs.3c13392. Epub 2024 Mar 7.
Impact-stiffening materials that undergo a strain rate-induced soft-to-rigid transition hold great promise as soft armors in the protection of the human body and equipment. However, current impact-stiffening materials, such as polyborosiloxanes and shear-thickening fluids, often exhibit a limited impact-stiffening response. Herein, we propose a design strategy for fabricating highly impact-stiffening supramolecular polymer networks by leveraging high-entropy-penalty physical interactions. We synthesized a fully biobased supramolecular polymer comprising poly(α-thioctic acid) and arginine clusters, whose chain dynamics are governed by highly specific guanidinium-carboxylate salt-bridge hydrogen bonds. The resulting material exhibits an exceptional impact-stiffening response of ∼2100 times, transitioning from a soft dissipating state (21 kPa, 0.1 Hz) to a highly stiffened glassy state (45.3 MPa, 100 Hz) with increasing strain rates. Moreover, the material's high energy-dissipating and hot-melting properties bring excellent damping performance and easy hybridization with other scaffolds. This entropy-driven approach paves the way for the development of next-generation soft, sustainable, and impact-resistant materials.
经历应变率诱导的从软到硬转变的冲击硬化材料作为人体和设备防护中的软质装甲具有巨大潜力。然而，当前的冲击硬化材料，如聚硼硅氧烷和剪切增稠流体，通常表现出有限的冲击硬化响应。在此，我们提出一种通过利用高熵罚物理相互作用来制造高冲击硬化超分子聚合物网络的设计策略。我们合成了一种由聚（α-硫辛酸）和精氨酸簇组成的全生物基超分子聚合物，其链动力学由高度特异性的胍基-羧酸盐桥氢键控制。所得材料表现出约2100倍的异常冲击硬化响应，随着应变率增加，从软耗散状态（21 kPa，0.1 Hz）转变为高度硬化的玻璃态（45.3 MPa，100 Hz）。此外，该材料的高能量耗散和热熔性能带来了出色的阻尼性能以及与其他支架易于杂交的特性。这种熵驱动方法为下一代柔软、可持续且抗冲击材料的开发铺平了道路。
