Current processing of engineering materials relies on calving, molding, extruding, rolling, packing, and weaving of solid materials. However, Mother Nature’s toolbox for creating things is far beyond just solids. Clearly both solid and liquid play indispensable roles in living systems and the magical combination of the two by Mother Nature produces a wide spectrum of exquisite properties. For example, articular cartilage, a natural hydrogel that contains 70% water, can maintain impressively high fracture toughness under millions of cycles of loads. Skeletal muscles can achieve high actuation stress, strain and energy efficiency, yet operating over years. Mussel secrets soft glues to form extremely robust adhesions to rocks and metals in flowing water with high salinity. The underlying principles and tactics totally elude current synthetic technologies.

The liquid-solid hybrid soft material’s concept opens new avenues for novel dynamic adaptive mechanisms and new multifunctional materials. Its hybrid nature offers tremendous combinatorial potential for mixing and matching a broad range of inputs and outputs. In recent years, there have been noticeable efforts in this line of studies. For instance, various stimuli-responsive hydrogels have been developed and widely applied as actuators, sensors, drug carriers, and tissue scaffolds; liquid inclusions have been explored to tune the mechanical properties of soft materials; liquid-impregnated porous substrates could be used to generate tunable wettability and optical properties. The new emerging manufacturing techniques also bring new space for design. The understanding of how to integrate these recent advances in material properties and function (e.g. toughness, self-healing, multi-functional hydrogels) with manufacturing (3D/4D printing) for the purpose of building smart materials is incomplete.

This symposium will bring together experts from diverse and multidisciplinary research areas with a strong interest in soft living materials such as biopolymer, synthetic hydrogels and liquid infused porous materials. Together they will contribute to the improvement in mechanical and chemical performance of these materials, and to expand the capability of additive manufacturing techniques to include actuating and responsive elements. This symposium will cover the complete range of fundamental mechanics, physics and materials science research to application areas such as tissue engineering, bionics and soft robotics. The following scientific questions will be discussed: What are nature’s strategies in designing various soft living materials? How to fabricate soft materials that possess properties and functions as living organisms? Can we integrate soft living and engineered machines to create new forms of machines or life?

adhesion adsorption diffusion elastic properties ion-solid interactions reactivity strength surface chemistry toughness viscoelasticity