Fuente: Journal of applied polymer Lugar: RESEARCH ARTICLE Ethylene-vinyl acetate effectively compatibilizes waste polyethylene with bitumen, enabling a finely dispersed morphology with strong interfacial adhesion. The resulting ternary system exhibits significantly enhanced self-healing properties, demonstrating that waste plastics can be valorized as functional additives rather than mere fillers in bitumen modification.

ABSTRACT
This study systematically investigates the synergistic enhancement of self-healing properties in bitumen through the incorporation of waste polyethylene (WPE) and ethylene-vinyl acetate (EVA) as a compatibilizer. A series of modified bitumen samples with varying WPE/EVA ratios were prepared via high-shear melt-blending. Comprehensive characterization was conducted, including morphological analysis, chemical structure examination, conventional tests, storage stability assessment, viscoelastic rheology, and self-healing efficiency quantification. The results demonstrate that EVA effectively compatibilizes the inherently immiscible WPE and bitumen, leading to a finely dispersed and homogenous morphology with strong interfacial adhesion. This optimized microstructure not only ensures excellent storage stability (ΔT < 2.2°C) but also significantly improves the stiffness (complex modulus up to 5.95 MPa at 0.1 rad/s) and thermal resistance (softening point up to 57.1°C). Most notably, the ternary system with 3 wt% WPE and 3 wt% EVA achieved a remarkable self-healing efficiency of 45.8%, which is 60% higher than that of neat bitumen, attributed to a synergistic mechanism combining bitumen capillary flow and polymer-induced elastic recovery. This work presents a sustainable and high-performance pavement binder that valorizes plastic waste while concurrently enhancing mechanical properties and autonomous healing capability.