A sustainable functionalization strategy to improving the material properties of bitumen by incorporating graphene

Abstract

Bitumen is a colloidal system with excellent binder properties, but with poor thermo-mechanical properties. This leads to a poor service life, and as a petroleum derivative this implies a negative environmental impact. To enhance its properties, attempts have been made to modify bitumen with highly thermally conductive nanoparticles, like graphene derivatives. However, the incorporation of graphene derivatives is a challenge due to detrimental interactions between graphene derivatives and asphaltene aggregates, which reduce the colloidal stability. With this study, we show how to not only maintain but also enhance the colloidal stability of bitumen by functionalizing graphene with suitable molecules. By the molecular wedging method, a new and sustainable strategy is developed to overcome any detrimental effects. Thereby, we provide the first successful strategy – a roadmap – to incorporate graphene into bitumen without losing its colloidal stability or negatively affecting the desired properties of graphene.

Keywords

• Graphene modified bitumen
• Non-covalent functionalization
• Colloidal stability
• Asphaltenes
• Graphene
• Molecular wedging method