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Updated: Jan 30, 2026
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Isolation of Native Soil Microorganisms with Potential for Breaking Down Biodegradable Plastic Mulch Films Used in Agriculture
Published on: May 10, 2013
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Structural changes of cassava starch and polylactic acid films submitted to biodegradation process
Margarita Del Rosario Salazar-Sánchez1, Sergio David Campo-Erazo1, Héctor Samuel Villada-Castillo1
1Grupo de Investigación en Ciencia y Tecnología de Interés Agroindustrial, CYTBIA, Departamento de Ingeniería Agroindustrial, Facultad de Ciencias Agrarias, Universidad del Cauca, 190002, Cauca, Colombia.
International Journal of Biological Macromolecules
|February 2, 2019
Summary
This study shows that biodegradable films made from polylactic acid (PLA) and starch undergo disintegration and fragmentation during composting. These eco-friendly packaging materials exhibit structural changes throughout the biodegradation process.
Area of Science:
- Materials Science
- Environmental Science
- Polymer Chemistry
Background:
- Polylactic acid (PLA) and starch are utilized in packaging as biodegradable alternatives to petroleum-based products.
- These materials offer environmental benefits due to their eco-friendly nature.
Purpose of the Study:
- To evaluate the structural and surface changes of a cassava starch and PLA composite film during biodegradation.
- To analyze the biodegradation process under standard compost conditions (ISO 4855-2:2007).
Main Methods:
- Extrusion was used to manufacture the composite film.
- Fourier Transform Infrared Spectroscopy (FT-IR) identified functional groups.
- High-Resolution Optical Microscopy (HROM) and Scanning Electron Microscopy (SEM) examined structural and surface alterations.
Main Results:
- The addition of PLA increased the carbonyl index in the composite film.
- Anhydrous malic acid (MA) in PLA/Thermoplastic Starch (TPS) mixtures may further increase the carbonyl index.
- The TPS/PLA composite film exhibited three biodegradation phases: disintegration, fragmentation, and mineralization.
- By week 4, the film showed reduced size, thinning, and fractures, indicating disintegration and fragmentation.
Conclusions:
- The TPS/PLA composite film demonstrated a complete biodegradation cycle under compost conditions.
- Structural and surface analyses confirmed the material's degradation pathway.
- The findings support the use of starch-PLA composites as sustainable packaging solutions.
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