As the bitumen binder in asphalt degrades from ultraviolet-light exposure, oxidation, and mechanical and thermal stresses, crumbling roads appear as a familiar feature of modern transportation infrastructure. Road surfaces are expensive to replace not only from a direct financial perspective but also from indirect costs like lost commuter time and other environmental impacts. To extend the lifetime of asphalt surfaces in an economical manner and replace a fraction of their fossil-fuel-based materials, researchers at NREL and Arizona State University have developed materials and methods to integrate waste plastics within asphalts. By diverting waste plastics into asphalt, these waste plastics represent an economical and existing-process-compatible additive to form composite asphalt materials that are more durable and more eco-friendly than those with only bitumen asphalt binders.
Researchers at NREL and Arizona State University have developed materials and methods for modified asphalts including polymer composites derived from waste-plastic streams. These polymer composites consist of (1) waste-plastic compatibilizers that are surfactants and improve the mixing, dispersion, and interfacial bonding of recycled plastic particles with bitumen and (2) recycled polyolefin and terephthalic-based particles, which add strength and replace a portion of the fossil-fuel-derived asphalt.
To make the compatibilizers, researchers at NREL and Arizona State University have developed economical and efficient single-pot methods to react waste plastics with amine moieties—thereby digesting the waste plastics to form a compatibilizing surfactant for the dispersed particles within the bitumen. The properties of the composite asphalt can be tailored by selecting a range of hydrocarbon chain lengths of the recycled particles to avoid their segregation and enhance asphalt healing capacity and resistance to aging.
To learn more about Durable, Economical, and Eco-Friendly Asphalt Partially Made from Waste Plastics, please contact Eric Payne at:
Applications and Industries
- Asphalt manufacturers, suppliers, and distributors
- Chemical manufacturers and suppliers
- Transportation-infrastructure authorities
The materials and methods for modified asphalts
- Are compatible with industry-standard hot-mix preparation methods,
- Use waste-plastic streams that could include inexpensive low-quality scrap,
- Can extend the service lifetime of asphalt infrastructure,
- Can potentially reduce input material costs,
- Can reduce the weight of asphalt for weight-sensitive infrastructure, and
- Can provide an eco-friendly alternative to conventional asphalts.