Dual-wavelength photopatterning unlocks spatially programmable heterogeneity in liquid crystal elastomers

Liquid crystal elastomers (LCEs) are blooming in soft robotics and intelligent devices due to their reversible and anisotropic deformation. To imitate sophisticated biological systems, photopatterning plays a crucial role in introducing programmable spatial heterogeneity into LCEs, due to its high resolution and non-contact operational simplicity. However, current photo-regulation methods either modify pre-formed homogeneous networks, offering limited tunability, or inevitably rely on thermal curing and specially designed monomers/reactions, which compromises spatial resolution, flexibility, and generality. Here, we introduce a dual-wavelength photopatterning strategy that enables spatially programmable heterogeneity directly during synthesis, using two wavelength of lights and the most widely accessible thiol-acrylate formulation in LCEs. By selectively triggering radical-mediated (365 nm) or base-catalyzed polymerization (450 nm), we create hard and soft networks with distinct properties. By flexibly regulating the triggering sequence and duration, we achieved seamless integration of continuous gradients within a single LCE: achieving the continuous tuning of modulus (1.3-14.8 MPa), actuation strain (54-93%) and, the broadest tuning range of nematic-isotropic transition temperature (Ti, 55-110 °C). It is indicated that even conventional LCE formulations can achieve multilevel encryption, mechanical differentiation, and bio‑inspired sequential actuation. This strategy establishes a versatile platform for designing functionally heterogeneous LCE devices for next-generation soft materials. Liquid crystal elastomers are of interest for soft robotics, though it is challenging to program response. Here the authors use a dual wavelength photopatterning method to tune mechanical properties and responsiveness.