A Solvent and Initiator Free, Low-Modulus, Degradable Polyester Platform with Modular Functionality for Ambient-Temperature 3D Printing

3D printing has enabled the design of biomaterials into intricate and customized scaffolds. However, current 3D printed biomaterial scaffolds have potential drawbacks due to residual monomers, free-radical initiators, solvents, or printing at elevated temperatures. This work describes a solvent, initiator, and monomer-free degradable polyester platform for room temperature 3D printing. Linoleic acid side chains derived from soybean oil lowers the Tg and prevents packing and entanglement, ensuring that G″ > G′ during room temperature printing. Upon printing, cross-linking of pendant functionalized coumarin moieties fixes the viscous filaments to elastomeric solids. Furthermore, the modular design of the polyester platform enables conjugation of ligands, as demonstrated by the conjugation of FITC to surface amines on the 3D printed scaffolds. This low modulus, printable polyester platform addresses several design challenges in 3D printing of functional biomaterials and could potentially be useful in many ti...