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3D inkjet printing is a fast, reliable, and non‐contact bottom–up approach to printing small and large models and is one of the fastest additive manufacturing technologies available. These attributes position inkjet printing as a promising tool for the additive manufacturing of biomaterials, for example, tissue engineering scaffolds. However, due to the stringent technical rheological requirements of current inkjet technologies, there is a lack of photopolymer resins suitable for the inkjet printing of biomaterials. Hence, a novel ink engineered for 3D piezoelectric inkjet printing of biomaterials is designed and developed. The novel resin leverages a biodegradable amino acid phosphorodiamidate matrix copolymerized with a dialkyne ether to modulate the viscosity. Copolymerization with commercially available thiols facilitates the photochemical thiol‐yne curing reaction. The ink exhibits optimal viscosity, eliminating the need for solvents, as well as reliable jetting and sufficiently swift curing kinetics. Furthermore, the formulation is successfully demonstrated in an industrial inkjet printhead. Notably, the resulting materials have low cytotoxicity and, hence, have significant promise in advancing the applications of 3D inkjet printing of biological scaffolds. [ABSTRACT FROM AUTHOR]

Magnetoresponsive polymers have gained increased attention in the design of soft actuators as they can be spatially as well as temporally activated and enable an external noninvasive control of movement. By introducing the magnetoresponsive properties in photocurable resins, one can fabricate personalized and complex structures (via vat photopolymerization 3D printing), whose movement can be conveniently controlled by an external magnetic field. Advancing from acrylate‐based photopolymers, which often suffer from shrinkage stress, low monomer conversion, and oxygen inhibition, the fabrication of magnetoresponsive thiol‐click photopolymers containing Fe3O4 nanoparticles as magnetic fillers is highlighted. The addition of the thiol crosslinker yields soft and flexible polymer composites, whose cure kinetics, viscosity, thermal, and mechanical properties are studied as a function of the thiol and filler content. Although cure rate and final monomer conversion decrease with rising filler concentration, the cure kinetics is reasonably fast at 6 wt%. The short pot life, a result of thiol‐Michael reactions induced by Fe3O4 nanoparticles, and a high thiol content, are overcome by the addition of an appropriate stabilizer. As proof of concept, 3D structures are fabricated by digital light processing (DLP) 3D printing and their magnetically driven movement is demonstrated. [ABSTRACT FROM AUTHOR]