Fabrication of Remotely Activated Shape-Memory Polymer Composites via Single-Step Photopolymerization

Abstract

A simple one-step photopolymerization strategy is presented to fabricate multifunctional shape-memory polymer composites capable of remote and programmable light-triggered actuation. The composites integrate gold nanoparticles and semicrystalline poly(ethylene)-block-poly(ethylene oxide) nanoribbons within a cross-linked epoxy network. During curing, the block copolymer undergoes crystallization-driven self-assembly, generating micrometer-long nanoribbons that act as reversible thermal switching domains, while gold nanoparticles are simultaneously formed in situ, enabling efficient conversion of visible light into localized heat through plasmonic excitation. Spectroscopic and microscopic analyses confirm the successful incorporation of both components without compromising their native morphology. Differential scanning calorimetry reveals two distinct thermal events corresponding to the glass transition of the epoxy matrix and the melting of the polyethylene domains, providing two independently addressable switching temperatures. Under green-light irradiation, the embedded gold nanoparticles rapidly raise the local temperature, enabling not only remote activation of the shape-memory effect but also programmable sequential shape recovery by selectively activating each thermal transition through laser power adjustment. These results demonstrate that combining crystalline block copolymer nanostructures with plasmonic nanoparticles enables remotely controlled multi-stage actuation using a single external stimulus. This scalable and ambient-compatible approach provides a versatile platform for the design of light-responsive composites with tunable thermal and mechanical behavior, offering opportunities for applications in smart coatings, remote actuators, and programmable materials.