Morphogenic composites: Frontal polymerization induced autonomously shaped composites

Abstract

Traditional shaping and curing of continuous fiber composites is an equipment, time, labor, and energy intensive process. This work investigates the integration of frontal polymerization (FP) with additively printed continuous-fiber tows to produce composite structures with controlled curvature. We combine the patterned tows with frontally polymerizable gel of poly(dicyclopentadiene) (pDCPD) to achieve rapid, autonomous, energy efficient, and predictable 3D curvatures, referred to as morphogenic composites. Due to the transient wave-like nature of FP, the propagation direction of the reaction front provides an additional means to vary the final shape of the morphed composite part. Digital image correlation and numerical simulation are used to quantify the influence of the transient strain effects, initiation locations, and front propagation paths on the composite’s final 3D shape. Overall, morphogenic composites can be autonomously and rapidly morphed to predictable and diverse 3D shapes through frontal polymerization with low energy and without tooling.