Study of PLA / TPU /Sodium Lignosulfonate Composite for Eco‐Friendly 3D Printing of Wood‐Like Materials

Polylactic acid (PLA) is a popular biodegradable polymer but suffers from brittleness and limited aesthetic options. To address this, we developed eco‐friendly wood‐like composites via melt blending of PLA, thermoplastic polyurethane (TPU), and sodium lignosulfonate (LS). TPU served as a toughening agent, increasing the elongation at break by 112%, while LS provided a wood‐like color and improved interfacial adhesion. The structural, morphological, thermal, mechanical, and chromatic properties of the composites were systematically investigated. The optimized composite (with 2 wt% LS) exhibited a minimal color difference (Δ E = 5.72) compared to poplar wood, good thermal stability, and enabled high‐fidelity 3D printing of wood‐grain textures with over 92% reproduction accuracy. This work presents a sustainable and versatile material for personalized and eco‐friendly 3D printing applications.