The reinforcing effect of montmorillonite on thermoplastic starch/low density polyethylene matrix

Document Type : Original Paper


1 Polymeric Materials Research Group, Department of Materials Science and Engineering, Sharif University of Technology, 11155-9466, Tehran, Iran.

2 polymeric materials research group, Department of Materials Science and Engineering, Sharif University of Technology Tehran,iran

3 Soil Science Department, Faculty of Agricultural Engineering and Technology, University College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran.


As the needs to replace the petroleum-based polymers with more environmentally friendly ones has been growing continuously over the past two decades. As a matter of the fact, lower material costs, easy processing and environmental concerns are the major driving forces for using biodegradable polymers. On the contrary, low mechanical properties and high hydrophilicity are the main challenges of natural polymers. consequently, recently research has focused on the composite preparation. One of the most effective approach to reduce these limitations is blending of thermoplastic starch (TPS) as a biodegradable polymer with the petroleum-based polymers and nanoclay to preparation a nanocomposite with satisfying mechanical properties. In this study, montmorillonite nanoclay was added as as reinforcing agents to alloy of TPS/low density polyethylene (LDPE) by twin-extruder in presence polyethylene grafted maleic anhydride (PE-g-MA). The addition of 5 phr (part per hundred) nanoclay increased the tensile strength and Young’s modulus of the samples by 53% and 19% respectively in comparison to those that have not PE-g-MA. The X-ray diffraction (XRD) was also implemented to investigate the intercalation and exfoliation phenomena. Soil burial biodegradation tests, carried out for samples and followed by CO2 emitted measurements, revealed that biodegradation was enhanced for the hybrid materials in comparison with low density polyethylene.