Pluripotent Hydrogels With Ion‐Tempered Mechanical Properties

ABSTRACT Functional soft materials have a wide application prospect in many fields. However, these materials often have elaborately designed polymer network structures to generate unique performance for specific applications. In this work, we present a versatile strategy for adjusting the mechanical properties and thermoresponsive behaviors of hydrogels by ion‐tempering, enabling their application in diverse scenarios. Thermoresponsive hydrogels with versatile applications are prepared by treating non‐thermoresponsive poly(acrylic acid) (PAA) hydrogels with acetate solutions containing metal ions of Mg 2+ , Ca 2+ , Sr 2+ , Mn 2+ , Ni 2+, and Zn 2+ , respectively. Except for poly(acrylic acid)/ magnesium acetate (PAA/MgAc), all the other hydrogels exhibit thermo‐induced phase separation behavior and shape memory properties with tunable hysteresis ratios. By exploiting the controllable recovery behavior of stretch‐programmed hydrogels, the poly(acrylic acid)/ manganese acetate (PAA/MnAc) hydrogel could be applied as artificial muscles and generate effective contractile actuation. Furthermore, the strong ionic bonds within the poly(acrylic acid)/zinc acetate (PAA/ZnAc) hydrogel provide remarkable energy dissipation capability, rendering it ideal for damping and impact protection applications.