Proactively modulating mechanical behaviors of materials at multiscale for mechano-adaptable devices.

How materials behave when subjected to mechanical stresses is studied by mechanics of materials. However, the application of flexible and stretchable devices exposes materials to dynamic mechanical environments. Therefore, mechano-adaptable materials and devices that can respond as pre-designed have been explored. There are two main ways to proactively modulate mechanical behaviors for materials, which involve molecular design and structural design. Molecular design has effectively integrated mechanically sensitive groups into synthetic materials for anticipated mechano-response. Structural design has broadened the boundary of conventional materials, generating mechanical metamaterials at multiscale with unique mechanical properties. Furthermore, molecular, structural plus systematic design for the application of mechano-adaptable devices have realized better electrical performance, human interaction, long-term sustainability, and even higher efficiency. Various devices based on design ideas are summarized and future challenges for proactively modulating mechanical behaviors of mechano-adaptable devices are discussed.