This study presents the mechanical characterization of polylactic acid (PLA) composites reinforced with agroindustrial waste, including agave bagasse, corn cob, and avocado pit, residues commonly found in the state of Jalisco. The aim of this work is to contribute to the development of sustainable materials, promote the generation of value-added products, and support the circular economy.

PLA composites were produced via injection molding and reinforced with 5 wt% natural fibers. Prior to processing, the fibers were dried and milled to ensure homogeneity and proper dispersion within the polymer matrix. Mechanical testing revealed a decrease in tensile strength ranging from 7% to 18% compared to neat PLA, primarily due to the incompatibility between the hydrophobic PLA matrix and the hydrophilic fibers. In contrast, flexural testing showed an increase in both Young’s modulus and flexural strength, indicating that fiber incorporation enhanced the rigidity of the composites.

These results demonstrate that agroindustrial fibers, despite reducing tensile strength, can improve the stiffness of PLA-based composites, making them suitable for potential applications such as rigid packaging, biodegradable trays, horticultural containers, and other products where structural rigidity is desired.

First author Andrea López González acknowledges the support of the Secretaría de Ciencia, Humanidades, Tecnología e Innovación  for the scholarship granted for her Master's studies.