Synergistic enhancement of mechanical, thermal, and 3D printing properties of polylactic acid via methyl methacrylate-modified pinus sylvestris char

This work used pinus sylvestris char (PS) modified with methyl methacrylate (MMA) surface functionalization as a filler, which effectively improved the mechanical properties (such as tensile strength , which increased by 166 %, and bending strength , which increased by 227 %), along with thermal stability and crystallinity of polylactic acid (PLA). Mechanistic studies have shown that the MMA units work through the formation of strong interactions (such as dipole forces and molecular bonding) as well as spatial effects of PS. This improves the interface between PLA and PS, effectively absorbing and dispersing stress, thus enhancing stress transfer and increasing the relaxation temperature of PLA molecular chains . This interaction also hinders the movement of PLA molecular chains in the molten state and strengthens the crystalline structure of PLA. The mechanical and thermal stability of modified PLA is superior to pure PLA when used for complex 3D printing . This provides a reference for synthesis optimization and performance enhancement of other green materials. • MMA reinforced pinus sylvestris char and PLA interface strength. • Pinus sylvestris char-PMMA increases the tensile strength of PLA by up to 166 %. • Pinus sylvestris char-PMMA enhances the thermal stability and crystallinity of PLA. • Composites exhibit excellent 3D printing properties.