Tailoring PLA/Gelatin Film Properties for Food Packaging Using Deep Eutectic Solvents

Area of Science:

• Materials Science
• Polymer Science
• Sustainable Packaging

Background:

• Poly(lactic acid) (PLA) is a biodegradable polymer with potential for food packaging.
• Improving PLA's properties is crucial for expanding its application range.
• Challenges include processability, mechanical strength, and barrier properties.

Purpose of the Study:

• To modify poly(lactic acid) (PLA) films using modified gelatin (Gel-mod) and a choline chloride/glycerol deep eutectic solvent (DES).
• To evaluate the effects of these additives on PLA's structure, morphology, thermal, mechanical, and barrier properties.
• To assess the compostability and suitability of the modified PLA for food packaging.

Main Methods:

• Melt processing of PLA with varying concentrations of Gel-mod and DES.
• Characterization using FTIR and SEM for structural and morphological analysis.
• Evaluation of thermal properties (Tg, crystallinity), mechanical behavior, processability, wettability, barrier performance, and compostability.

Main Results:

• Direct incorporation of Gel-mod resulted in better interfacial interactions and dispersion than the masterbatch method.
• DES acted as a plasticizer and nucleating agent, improving processability and crystallinity while maintaining thermal stability.
• Mechanical properties decreased, but PLA_4Gel-mod showed improved elongation at break and processability due to minimized degradation.
• Increased hydrophilicity led to higher water vapor transmission rates and accelerated biodegradation.

Conclusions:

• Synergistic incorporation of DES and gelatin effectively tailors PLA properties.
• The developed materials offer a viable strategy for compostable packaging films.
• Modified PLA films show potential for sustainable food contact applications.