Macroscopic Geometry-Dominated Orientation of Symmetric Microwrinkle Patterns.

Orientated wrinkle patterns with controlled microarchitectures are highly attractive because of their potential and broad application in technologies ranging from flexible electronic devices to smart windows. Here, we demonstrate a macroscopic, geometry-dominated strategy to fabricate symmetric microwrinkles with precisely controllable pattern dimensions and orientations through a dynamic interfacial release process. The release-induced approach is based on the release of multilayer elastomer composites from polymeric sacrificial layers in solutions combined with crosslinking-induced contraction of the elastomer substrates. Crosslinking-induced contraction provides the driving force for developing and stabilizing surface wrinkle formation, whereas the polymeric sacrificial layer provides a mild and simultaneous release process to form orientated wrinkles through kinetic control of local strain development. The macroscopic shape of the composite controls release kinetics, hence strain history, leading to the generation of photonic reflective surfaces. Moreover, stable wrinkles fabricated from various materials including metals, ceramics, and carbons can be achieved. This versatile, mold-free, and cost-effective platform technology demonstrates how global strain distributions can be harnessed through kinetics to drive local pattern development.