Vat photopolymerization of tough glassy polymers with multiple shape memory performances

Shape memory polymers (SMPs), undergoing shape-shifting from a predefined temporary shape to the original one under the external stimulus, have been employed in aerospace and other smart devices with this unique shape transformation feature. How to obtain SMPs with arbitrary geometries, excellent mechanical performances, and precisely controlled transformation pathways simultaneously is still challenging. Herein, we demonstrate vat photopolymerization of tough glassy polymers with multiple shape memory effects. By introducing sacrificial non-covalent hydrogen bonding within the polymer network, the printed SMPs exhibit excellent mechanical performance in the glassy state, e.g., a toughness of 38.3 +/- 4.3 MJ m- 3, Young's modulus of 1.1 +/- 0.1 GPa, breaking stress of 46.2 +/- 1.9 MPa, and strain-at-break of 99 +/- 14%. The multiple shape memory capability is derived from a single broad glass transition (ranging from 70 degrees C to 150 degrees C) introduced during the formulation of the resin. The printed tough multi-SMPs can be potentially applied as smart devices where both good mechanical performance and precise control of complex shape transformation are needed.

Automated summary

In this study, tough glassy polymers with multiple shape memory effects were successfully fabricated through vat photopolymerization with the introduction of sacrificial non-covalent hydrogen bonding within the polymer network. The printed polymers exhibited excellent mechanical performance in the glassy state and showed multiple shape memory capability.