Integrating shape-memory technology and photo-imaging on a polymer platform for a high-security information storage medium

Abstract

Shape-memory polymers (SMPs) have attracted enormous attention in recent years, but most of the research has been focused on the nature of the shape change itself. Actually, there is great potential as well as a big challenge to develop a new class of smart materials with the assistance of shape-memory technology (SMT). Herein, by integrating SMT and photo-imaging in one system, we proposed SMPs as a high-security storage medium featuring information storage, masking and dual-anticounterfeiting. In this work, an anthracene-containing polymer embedded with shape-memory component and photoactive moiety was elaborately designed. The shape-memory component determines the shape-change, that is, produces a three-dimensional (3D) signal, while the localized photo-cross-linking of the anthracene-containing film under 365 nm UV with a photomask generates a photo-image on the surface of the SMP, that is, a two-dimensional (2D) signal, due to the distinct boundaries of areas of strong and weak fluorescence. The stored information, the 2D image produced by photo-imaging, could only be verified by 254 nm UV resource, and with the integrated SMT-generated 3D signal, the safety level of the information could be improved. By implementing sequential photo-imaging and SMT, the high-security information storage medium was proved by a model of a scroll and a practical example of a label.