Low‐Entropy‐Penalty Elastomers With Synergistic Resilience and Strength Via Resilin‐Inspired Microphase Separation

Abstract The inherent trade‐off between elasticity and strength in elastomers continues to present a significant challenge due to the difficult‐to‐reconcile soft and hard networks. In this study, inspired by the heterogeneous structure of resilin in dragonfly cuticle, a nano/micro engineering is introduced to regulate microphase separation by constructing dynamic hard domains with well‐defined sizes, optimal spacing, and uniform aggregation. During deformation, the dynamic hard domains progressively disintegrate, while strain‐induced crystallization (SIC) occurs in the soft segments. This process is governed by an entropy‐enthalpy compensation mechanism to minimizes the net Gibbs free energy barrier (ΔG = ΔH – TΔS), which therefore establishes a synergistic balance between entropy gain (ΔS↑) due to domain disassembly and enthalpy release (ΔH↓) resulting from SIC‐induced lattice ordering. Upon recovery, the reversible SIC interfaces release stored interfacial Gibbs energy (ΔGs) to compensate the conformational entropy loss (‐TΔS), thereby facilitating molecular rearrangement. Consequently, the proposed elastomers exhibit minimal entropy penalties and achieve recovery efficiency over 88% along with a record tensile strength exceeding 80 MPa. Additionally, the elastomers show outstanding toughness, tear strength, and puncture resistance. This low‐entropy‐penalty strategy paves the way toward resolving the elasticity and strength conflict in elastomers, advancing the functional elastomer machines for engineering applications.