Use of Recycled Low-Density Polyethylene for Production of Asphalt Mixture: Performance and Emission Characteristics

Abstract Recycled plastic modified asphalt mixtures show varied performance due to the variability in dosage, differences in source of materials, incorporation method, inconsistency in modification techniques, and absence of global standardization. This study addresses the existing research gaps by evaluating the performance and emission characteristics of recycled low-density polyethylene (RL) modified asphalt mixtures (RLMA) produced using dry and wet modification. The RL content was optimized at 8% and 2% (by weight of asphalt binder) for the dry and wet processes, respectively. Five different types of RL in two shapes, collected from four sources were used for RLMA preparation. The moisture resistance of RLMAs prepared using dry and wet modification methods showed similar results, with an average of 5.3% improvement over the control mix (CM). Wet modification exhibited 29.56% higher resilient modulus due to higher binder viscosity. The wet modified mixes showed slightly better rutting resistance compared with dry method, although the difference was not statistically significant. Both modification methods exhibited reduced cracking resistance when RL was incorporated. The emission characteristics of RLMAs were found to be independent to type, source, and incorporation method of RL, compared with control mix, with fume levels remaining safely below standard limits.