This study explores a sustainable method for bioplastic production using agricultural waste. Polylactic acid (PLA)-based films were developed by incorporating cellulose extracted from rice husks (RH) and sunflower stalks (SS). The cellulose extraction process achieved an average efficiency of 85% based on total agricultural waste mass. Chemical structures of PLA and composite films were examined using FTIR spectroscopy. All films were flexible and transparent, with pure PLA films exhibiting higher transparency. Such properties make PLA films ideal for packaging, biomedical, and electronic applications due to their lightweight and adaptable nature. Films containing SS-derived cellulose showed slightly greater thickness (0.197–0.232 mm) compared to those with RH cellulose. FTIR analysis revealed interactions between PLA and cellulose, indicated by reduced intensity of the –OH stretching band at 3338 cm⁻¹ and PLA characteristic peaks at 1452, 1748, and 1181 cm⁻¹. These changes suggest hydrogen bonding and limited polymer chain mobility due to conformational adjustments. The spectra of composite films resembled those of PLA and cellulose, confirming enhanced crystallinity and molecular interactions. This is the first comparative study using cellulose from both RH and SS in PLA-based bioplastics, demonstrating their combined potential as sustainable reinforcements for biodegradable materials.

PETG composite filaments containing 1 wt%, 3 wt%, and 5 wt% hexagonal boron nitride (h-BN) were produced. The produced filaments were transformed into test specimens using the fused deposition modeling (FDM) technique. The tensile, compression, and wear behaviors of the composite polymer test specimens produced by the FDM method were investigated. The wear characteristic was measured using a ball-on-flat tribometer under normal loads of 5, 10, and 15 N. The worn surfaces were characterized by profilometer, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). PETG/1hBN showed the lowest coefficient of friction (COF) at all tested loads and provided a 40–46% reduction compared to neat PETG. In addition, it was observed to have the wear track with the lowest depth and the smoothest surface. Furthermore, the highest compressive yield strength among the investigated compositions was reached in these specimens. For specimens containing higher h-BN contents, a proportional improvement could not be achieved, and this was interpreted as being due to the agglomeration of the filler material reducing its effectiveness in the transfer film layer. These results show that the addition of a low amount of h-BN to PETG is an effective and easily processable method for improving the wear resistance of the PETG matrix.