Digital coding of mechanical stress in a dynamic covalent shape memory polymer network

作者：Zhang Guogao; Peng Wenjun; Wu Jingjun; Zhao Qian; Xie Tao^*

来源：Nature Communications, 2018, 9(1): 4002.

DOI：10.1038/s41467-018-06420

Controlling stresses in materials presents many unusual opportunities for their engineering applications. The potential for current approaches is severely limited by the intrinsic tie between the stress and the geometric shape. Here, we report a material concept that allows stress management in a highly efficient digital manner while decoupling the stress and the geometric shape. This is realized in a dynamic covalent shape memory polymer network, for which the elastic shape memory sets the baseline stress level and maintains the geometric shape while the plasticity enabled by the dynamic bond exchange allows stress tuning. With a digital gray scale photothermal mechanism, any arbitrarily defined stress distribution can be created in a free-standing polymer film. The naturally invisible stresses can be further visualized as mechanical colors under polarized light, revealing its potential for encoding hidden information. Our approach expands the technological potential in many areas for which stresses are relevant.

• 出版日期2018-10-1
• 单位浙江大学