ENHANCING THE MECHANICAL PROPERTIES OF BIO-BASED FILMS FOR FOOD PACKAGING

The increase in global population has intensified the need for innovative waste management solutions, making biodegradable plastics increasingly important. Polylactic acid (PLA) is one of the most widely used biobased and biodegradable polymers in the packaging industry due to its biocompatibility and environmental sustainability. However, PLA is inherently brittle and rigid, which limits its processing and packaging performance. To overcome these limitations, this study investigates the incorporation of Mater-Bi, a flexible biobased granule commonly used in shopping bags, into PLA films. Biodegradable films were prepared with varying PLA/Mater-Bi ratios: 100% PLA, 80% PLA–20% Mater-Bi, 70% PLA–30% Mater-Bi, 60% PLA–40% Mater-Bi, and 100% Mater-Bi. The films were characterized for mechanical properties, including thickness, surface density, tensile strength, elongation at break, and puncture resistance. Sealing performance was assessed to ensure food safety, while optical properties were evaluated to meet marketing requirements. FTIR spectroscopy was performed to analyze molecular interactions, and residual solvent levels were verified using gas chromatography to comply with food safety standards. Results indicated that increasing Mater-Bi content enhanced film flexibility and elongation but reduced tensile strength and puncture resistance. Transparency decreased with higher Mater-Bi content, producing a more yellowish tint compared to pure PLA. This study provides a methodology for optimizing PLA-based biodegradable films, offering an alternative for sustainable food packaging with improved mechanical performance.