Mechanical and Flow Properties of Virgin and Recycled Low-Density Polyethylene (LDPE) Blends Using Twin Screw Extrusion

Abstract:

The utilization of recycled materials in the production of plastic products is an environmentally conscious and economically viable approach. This study delves into the mechanical and flow properties of low-density polyethylene (LDPE) blends, comparing virgin low-density polyethylene (vLDPE), recycled low-density polyethylene (rLDPE) and vLDPE/rLDPE blends with different ratio (100/0, 75/25, 50/50, 25/75, 0/100) for the purpose of reprocess into variable high-quality end products with minimal modification. Mechanical properties, such as tensile strength, elongation at break, Young’s modulus, flexural strength, and flexural modulus, were examined to assess the suitability of rLDPE in comparison to its virgin counterpart. Our results demonstrate that vLDPE/rLDPE blend exhibits mechanical properties comparable to those of vLDPE, suggesting its potential as a sustainable alternative for reprocessing. Flow properties, specifically melt flow index (MFI), were also assessed to evaluate the processability of the LDPE blends. The findings reveal that the flow properties of LDPE blends are within an acceptable range for extrusion moulding, indicating that these materials can be effectively processed without major adjustments to manufacturing processes. This research underscores the feasibility of incorporating rLDPE into vLDPE for reprocessing into variable products, offering both economic and environmental advantages. By extending the lifecycle of LDPE materials through recycling, we can contribute to reducing waste and the overall environmental footprint while maintaining the desired mechanical and flow properties for high-quality end products.

• Periodical: Key Engineering Materials (Volume 997)
• Pages: 71-80
• DOI: https://doi.org/10.4028/p-9y67Y5
• Online since: December 2024
• Authors: Cee Kee Lim*, Mohd Hanif Mohd Pisal, Kean Chong Lim, Muhamad Nurfirdaus Baddrulsham, Joemer Absalon Adorna Jr
• Keywords: Low-Density Polyethylene, Melt Blending, Polymer Blend, Recycle, Reprocessing

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