Synthesis and characterization of dextran palmitate for extrusion 3D printing

The fabrication of objects with complex shape and geometry has been greatly facilitated with the advancements in additive manufacturing. While synthetic polymers like ABS and PLA have found widespread use in extrusion 3D printing, other biobased thermoplastics that are both biodegradable and biocompatible could offer strategic advantages over traditional synthetic materials. In this work dextran of low (20 kDa) and medium (40 kDa) molecular weight (MW) was modified with palmitic acid to obtain meltable polymers for extrusion 3D printing/fused deposition modeling additive manufacturing. The dextran derivatives were characterized by FTIR, NMR and elemental analysis. The degree of substitution (DS) varied between 0.94 ± 0.31 and 1.36 ± 0.16. Our findings reveal a melting temperature near 40 °C, independent of the DS or MW. Extrudability varied depending on the DS. Cubes with dimensions of 15 × 15 × 10 mm³ were printed from the dextran palmitate. The swelling degree of the cubes in water remained limited, up to 0.17 ± 0.02 g/g. This work demonstrates the great potential of dextran palmitate as biobased and biodegradable polymers for 3D printing for future applications in human health.