Spatially Tailorable Liquid Crystalline Elastomer Alignment During Digital Light Process 3D Printing

Abstract

Liquid crystal elastomers (LCEs) are anisotropic polymeric smart materials with promise for soft robotic actuators, dampers, and adhesives. Realizing these applications requires precise 3D alignment of the polymer backbone, yet current manufacturing approaches struggle to produce complex spatial patterns in three dimensions. Here, we introduce a digital light processing (DLP) 3D printing strategy that enables voxel-level control of LCE alignment domains. By integrating a rotatable magnetic array with DLP photomasking, we achieve spatially tunable structures at voxel resolutions. This approach allows freeform 180° alignment within individual voxels, generating highly nonlinear shape transformations in both 2D films and 3D architectures. Finite element modeling and inverse design guide the creation of multidomain alignment patterns that could achieve targeted nonlinear deformation behaviors. As a demonstration, multidomain LCE smart valves are fabricated that exhibit up to 70% improved flow control compared to monodomain analogues. This technique dramatically expands the design space of 3D programmable matter and establishes a pathway toward complex, application-ready LCE systems.