Mechanical and Biodegradation Properties of Warp Knitted Polylactic Acid (PLA) for Smart Food Packaging Applications

Packaging is one of the essential elements of today’s life and it plays a major role in our daily lives. Packaging is inevitable to different communities of people: manufacturer’s shopkeepers, sellers, and consumers. Food packaging is crucial for prevents contamination and preserves quality by reducing spoilage, extending shelf life, and ensuring safety. In the recent years, various studies have been executed on biodegradable materials to replace petroleum based plastics for food packaging applications. The demand of biodegradable packaging is increasing as it can be disposed with minimum environmental impact, but the growing market is still in its infancy predominantly due to the lack of materials. Biodegradable polymers such as PLA has given a significant attention in food packaging because it has an excellent properties such as environmentally, friendly, biocompatibility and energy savings. So, this study investigates the mechanical and biodegradation properties of 18 warp knitted polylactic acid (PLA) samples, produced with pick densities of 2, 3, and 4 courses/cm and mesh sizes ranging from 0.03 to 10.37 cm², for smart food packaging applications. Mechanical tests (tensile strength, burst resistance, abrasion resistance) revealed an inverse relationship between mesh size and strength, with sample P4M (mesh size 0.03 cm²) achieving the highest tensile strength (78.67 N/m²) and burst resistance (773.33 kPa). Biodegradation tests showed complete decomposition in soil after 8 months. PLA fabrics infused with red cabbage indicator exhibited color changes to detect banana ripening, demonstrating smart packaging functionality."