Bone-Inspired Self-Adaptive Material and Its Application for Reprogrammable and Reversible Self-Folding Structures

Adaptability is one of the hallmarks of living systems that provide resilience in a dynamically changing environment. I will present our efforts to study mechanically adaptive materials for dynamically changing loading environments by coupling stress with material synthesis. We are inspired by the findings that bones are formed by mineralizing ions from blood onto collagen matrices. I will present a material system that triggers proportional mineral deposition from electrolytes on matrices upon mechanical loadings. For example, the mineralization rate could be modulated by controlling the loading condition, and a 30-180% increase in the modulus of the material was observed upon cyclic loadings. The mineral growth shows a self-limiting behavior tunable by force, which we could model analytically. To expand the environment where the material can be utilized, we investigated the synthesis of liquid-infused porous piezoelectric composites inspired by bone and pitcher plants. I will present our synthesis approach and resulting properties. The material showed 36 times increase in modulus and 30 times increase in dissipation after 12 million loading cycles. I will also present our approach for reprogrammable self-configurable structures based on the material by controlling the modulus distribution through the applied loading. We envision that our findings can contribute to new strategies for making resilient materials for dynamically changing mechanical environments.