Ruiz-Franco José, Giuntoli Andrea
Zernike Institute for Advanced Materials, University of Groningen, Groningen, The Netherlands.
Nat Commun. 2025 May 1;16(1):4085. doi: 10.1038/s41467-025-59426-6.
Polymer glasses such as the plastics used in pipes, structural materials, and medical devices are ubiquitous in daily life. The nature of their low molecular mobility is still poorly understood and it leads to brittle mechanical behavior, damage, and fracture over time. It also prevents the design of self-healing mechanisms that expand the material's lifespan, as more commonly done in recent years for higher mobility amorphous polymers such as gels and rubbers. We demonstrate through numerical simulations that controlled oscillatory deformations enhance the local molecular mobility of glassy polymers without compromising their structural or mechanical stability. We apply this principle to increase the molecular mobility around the surface of a cylindrical crack, counterintuitively inducing fracture repair and recovering the mechanical properties of the pristine material. Our findings are a first step to establish a general physical mechanism of self-healing in glasses that may inspire the design and processing of new glassy materials.
诸如用于管道、结构材料和医疗设备的塑料等聚合物玻璃在日常生活中无处不在。它们低分子流动性的本质仍未得到充分理解，并且随着时间的推移会导致脆性机械行为、损伤和断裂。这也阻碍了自修复机制的设计，而自修复机制可以延长材料的使用寿命，近年来在凝胶和橡胶等高流动性无定形聚合物中更常见。我们通过数值模拟证明，受控的振荡变形可增强玻璃态聚合物的局部分子流动性，而不会损害其结构或机械稳定性。我们应用这一原理来提高圆柱形裂纹表面周围的分子流动性，反直觉地诱导裂缝修复并恢复原始材料的机械性能。我们的发现是建立玻璃自修复一般物理机制的第一步，这可能会激发新型玻璃材料的设计和加工。
