Coaxial Melt Electrowriting

ABSTRACT Coaxial melt electrowriting (MEW) was established and produced dual‐property microfibers with diameters ranging from 1.6 to 29.2 µm. Integrated into the MEWron hardware platform, this system achieves stable Taylor cone formation and jetting, with performance visualized and quantified by using polycaprolactone blended with two color contrasting [ n ]cycloparaphenylene fluorophore additives. Material switching tests demonstrated controlled transitions within 12 min of pressure adjustment, enabling binary and gradient dual‐property scaffolds. Design of experiments characterized the effects of the core and shell pressure ratios on fiber diameter and jet stability across a functional window. Following a 20‐min stabilization period to ensure jet stability, the system displayed distinct regimes of linear deposition, nonlinear patterns, and coiling geometries. Functional demonstrations include the fabrication of dual‐thermochromic scaffolds operating as microfiber thermal sensors with visible transitions at 10°C and 31°C and combined magnetic‐thermochromic scaffolds exhibiting both properties within discrete fiber regions. By enabling coaxial distribution of multiple materials within individual microfibers, this study expands MEW capabilities from single‐material architectures to multi‐functional, compositionally programmable microfiber prints that were made on open‐source hardware that is accessible to the broader research community.