A tremendous amount of work is done by rheologists and engineers to measure the physical properties of asphalt. No attention is paid to improving the physical properties. The major method of improving asphalt binder properties is modification with polymers, typically styrene-butadiene-styrene polymers, a technique developed in the United Kingdom nearly 40 years ago. Some chemical modification is done on asphalt for specialized high-cost applications, such as joint sealants and bridge deck pavements. We want to investigate modifying asphalts with different monomers, such as butadiene (or replacements for butadiene containing polymers), epoxy, urethane, acrylic, silane, etc., with a view to developing asphalt with enhanced physical properties in terms of tensile strength, elasticity, fatigue aging, and water resistance.
A number of polymer materials were evaluated; however, only the isocyanates improved the performance of the asphalt binders. Epoxy and acrylic monomers did not show any binder performance grade (PG) increase.