MODIFICATIONS OF BITUMEN BY ELASTOMER AND REACTIVE POLYMER—A COMPARATIVE STUDY

With increasing demand for higher performance, different modifications to asphalt are being explored. Asphalt is expected to become harder on modification thereby improving its life span. The modification further helps asphalt in developing resistance to cracking/fatigue at low temperatures and stability with minimum creep at higher temperatures. Polymers and rubber are being blended with asphalt to obtain good low temperature as well as high temperature performance. Various factors such as polymer chemical nature, molecular weight and particle size play a crucial role in determining the effect of modified asphalt properties. The effect of these factors and physical/chemical interaction between the additive and asphalt has not yet been fully established due to limitations in appropriate evaluation methodologies. This paper attempts to evaluate the improvements in modification of asphalt due to the addition of an elastomer and a reactive polymer, relatively. The evaluation is made more reliable and valid by considering all the three key characteristics namely cohesion, adhesion and durability aspects of the asphalt as the basis to highlight the improvements in application benefits.