Recent research in the asphalt industry has focused on promoting sustainability through reducing mixing and compaction temperatures. Sulfur-extended asphalt has been studied extensively for this purpose because of the reduction in price of asphalt concrete that sulfur offers, as well as reducing the mixing and compaction temperatures. However, sulfur can negatively impact the properties of bitumen at lower temperatures and offers little protection against moisture damage. Alternative and bio-based binders have also been explored, because the use of bio-modifiers reduces the cost of the end product and the amount of greenhouse gas emissions produced.
Bio-oils have also shown promising initial results in improving the mechanical properties of bitumen, but there are concerns pertaining to its susceptibility to moisture. Bio-oils naturally have a high acidic content, which promotes nucleation at the interface of bitumen and aggregates. The interactions between waste vegetable oil and sulfur have yet to be explored further to determine potential for improved properties for bitumen.
Researchers at Arizona State University have developed SulfCo, a novel method that enhances asphalt binder properties through the creation of an in-situ polymer within a bitumen matrix. This method involves utilizing sulfur and bio-oils, particularly those rich in unsaturated compounds like waste cooking oil and castor oil, to enable chain reactions that result in the formation of the in-situ polymer. Aiming to address the challenges posed by traditional polymer additives, SulfCo offers a cost-effective solution to enhance bitumen elasticity, crucial for minimizing permanent deformation and cracks in asphalt. Unlike conventional polymers, SulfCo's gradual elasticity development during curing preserves flowability, mitigating issues associated with mixing and compaction.
- Lower-Temperature Pavement Construction
- Sustainable Infrastructure
- Enhanced Pavement Performance
Benefits and Advantages
- Sustainable Alternative to Conventional Polymers
- Cost-Effectiveness and Price Stability
- Enhanced Performance and Durability
- Streamlined Mixing and Compaction