Complex 3D‐Printed Mechanochromic Materials with Iridescent Structural Colors Based on Core–Shell Particles

A scalable protocol for design and subsequent 3D-printing of polymeric core-shell-particles is reported. The particle synthesis by emulsion polymerization in starved-feed mode used tailoring architecture composition. Control size, mechanical properties, chemical functionalities allow to achieve the specific requirement profile extrusion-based additive manufacturing. core-shell particles consist hard polystyrene cores a comparably soft polyalkylacrylate-based shell. Size monodispersity, as well core-to-shell ratio, are determined means dynamic light scattering transmission electron microscopy. Thermal rheological properties investigated scanning calorimetry thermogravimetric analysis oscillation capillary rheometry. During 3D-printing, monodisperse self-assemble into an ordered close packed lattice structure, leading visible reflection colors according Bragg's law diffraction. Distinct angle-dependent recorded via UV-vis spectroscopy. As structural color depends, inter alia, on underlying sizes, resulting easily tunable adjusting applied parameters. Under deformation, changes due controlled which enables mechanochromic sensing with printed objects. They also promising candidates decorative ornaments, smart optical coatings, or advanced security devices.