OPTIMIZING PLA PERFORMANCE: EFFECTS OF INJECTION MOLDING PARAMETERS AND OROTIC ACID ON MECHANICAL, THERMAL PROPERTIES AND ITS COMPOSTABILITY

Polylactic acid (PLA) is a biodegradable, bio-based polymer derived from renewable resources, making it an attractive alternative to petroleum-based plastics in various industries. However, its limited mechanical properties and thermal performance hinder its application in high-performance sectors such as aerospace. This study investigates the impact of crystallization behavior on PLA's mechanical, thermal, and composting properties, focusing on enhancing PLA's crystallization through the addition of orotic acid (OA) as a nucleating agent. PLA samples were processed with varying injection molding parameters and compounded with 2wt. % OA to enhance crystallization. Differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), tensile testing, and industrial composting experiments were employed to evaluate the material's properties. The results demonstrate that the addition of OA significantly improved the crystallization of PLA, increasing its crystallinity from 17.34% to 53.44%, boosting the heat deflection temperature (HDT) from approximately 58°C to over 130°C, and enhancing ultimate tensile stress from 50.26 MPa to 59.63 MPa. These improvements in mechanical and thermal performance make PLA-2OA a more viable candidate for aerospace applications, where material durability and temperature resistance are crucial. Additionally, the material exhibited enhanced composting behavior, maintaining its biodegradability while achieving the necessary performance standards for high-stress environments in aerospace.