Multimaterials by Patterning Microphase Separation of a Single Copolymer

Abstract Living systems achieve robustness by integrating soft and rigid components into seamless architectures, yet synthetic emulation of this strategy remains limited. Here, we present a strategy to generate multimaterials from a single copolymer by patterning phase separation. Specifically, we design a block copolymer of metastable nanostructure, and then spatially program photocrosslinking to locally arrest phase separation at different levels during annealing, thereby producing patterns that span moduli from regimes of rubbers to plastics. The resulting multimaterial exhibits spatially distinct mechanical properties, but is chemically identical, and is seamlessly integrated through a shared polymer network topology. This approach inherently eliminates interfacial incompatibility of dissimilar materials, enhances structural integrity of the multimaterial, and establishes a versatile platform for programmable, multiscale rigid‐soft integrated devices.