Tough and fatigue-resistant functional elastomer enabled by hierarchical nanophase-separated microparticle-reinforced strategy

Enhancing the mechanical performance of rubbery materials while integrating functionality remains one of the timeless subjects for expanding their applications. Many current strategies often involve incorporating microscale fillers or nanoscale structure heterogeneity to reinforce rubbery materials. Structure heterogeneity at various scales within polymer networks is inferred to enhance the mechanical performance of rubbery materials. Herein, we propose a hierarchical nanophase-separated microparticle-reinforced strategy (denoted as NSMR strategy) to create tough, fatigue-resistant, and functional elastomers by integrating structure heterogeneity across different length scales. By integrating hierarchical heterogeneity across multiple length scales—from millimeter-sized microparticles to nanometer-scale phase-separated domains—we fabricated elastomers that are free-shapeable, strong, ultra-stretchable, and exhibit remarkable fatigue resistance, all achieved through a simple one-pot synthesis process. Notably, the incorporation of the ionic polymer poly(2-acrylamido-2-methyl-1-propanesulfonic acid) (PAMPS) imparts slight water-swelling capabilities to the NSMR elastomers, enabling novel applications beyond conventional dry rubbers. These functionalities include reversible information storage and on-demand activation/deactivation of sensing mechanisms. We believe this design concept offers a straightforward and versatile approach to creating advanced functional elastomers with enhanced mechanical properties and expanded application potential.