A comprehensive evaluation of mixture and binder properties to explore the use of low-density polyethylene (LDPE) as an asphalt modifier and co-modifier

ABSTRACT

There has been growing interest in the use of polyethylene (PE) in the asphalt industry as one way to mitigate the adverse environmental impact of waste plastics. The main goal of this study was to evaluate the potential use of low-density polyethylene (LDPE) as a modifier for use in asphalt mixtures. In addition, this study also explored the potential synergistic impact of using elastomeric polymers typically used with asphalt binders as a co-modifier along with LDPE. This study was based on a comprehensive evaluation of the rheological and performance-related properties of asphalt binder from two very different sources as well as asphalt mixtures produced using a subset of these binders. Typical methods that are standard practice in the industry and methods that are being developed to evaluate the performance metrics of asphalt binders and mixtures were used. The two chemically diverse base binders and redundancy in the evaluation process were introduced to ensure a more robust evaluation of the expected properties. Overall, results demonstrate that although the impact of LDPE on the expected performance of the binder may vary with the source of binder, LDPE can be successfully used to enhance the properties of the asphalt binder in most respects, particularly with the synergistic use of a conventional elastomeric modifier.

KEYWORDS:

• Waste plastics
• low-density polyethylene
• environmental impact
• rheological properties
• performance properties

Acknowledgments

All the statements are those of the authors. The authors also acknowledge the (i) co-funding of Qatar Petrochemical Company (QAPCO) for supplying the LDPE, and RAETEX; (ii) Kraton and Dow chemical for supplying the elastomers used in this study; and (iii) Mr. Tyler Seay for his help in laboratory evaluation of the materials.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the Qatar National Research Fund (QNRF): NPRP11S-1128-170041.