Physical Chemistry-Informed Multimaterial Printing of Rapidly Curing Resins

Frontal ring-opening metathesis polymerization (FROMP) enables rapid, energy-efficient curing of polymeric thermosets and provides a promising foundation for free-standing additive manufacturing. Despite its potential, most FROMP formulations remain incompatible with extrusion-based printing due to premature polymerization at low viscosities. We apply principles of polymer physics to establish how the projected chain pervaded volume and extent of chain transfer govern resin stability during polymer growth. Using these insights, we design copolymeric formulations that remain stable at print-relevant viscosities, enabling direct ink writing (DIW) of multimaterial thermosets. Building on this foundation, we introduce multimaterial morphogenic growth printing (MMGP),an engineering strategy that circumvents premature polymerization through direct FROMP of liquid resins. This advance extends our previously developed morphogenic growth printing (MGP) approach¹, which relies exclusively on DCPD-based systems, by integrating multiple reactive inks within a single, self-propagating front. We formulate a suite of co-monomeric and graft-copolymer inks with tunable crosslinking and energy densities that produce materials spanning over six orders of magnitude in stiffness (E ≈ 1 MPa–2 GPa). By adjusting resin composition and front energetics, MMGP enables the morphogenesis-inspired creation of interfaces—ranging from continuous mechanical gradients that emulate tendon-to-bone transitions to discrete junctions reminiscent of articulating joints. These structures exhibit exceptional cohesion without delamination, even under repeated flexural loading, highlighting the synergy between physical and organic chemistry in advancing next-generation additive manufacturing.

 

 

References

[1] Kim, Y. S.; Zhu, M.; Hossain, M. T.; Sanders, D.; Shah, R.; Gao, Y.; Moore, J. S.; Sottos, N. R.; Ewoldt, R. H.; Geubelle, P. H.; Tawfick, S. H. Morphogenic Growth 3D Printing. Advanced Materials 2025, 37 (20).