The Copolymers and their Effect on the Rheological Properties of Sulfureted Asphalt

Abstract

Due to the harsh climatic conditions and the maximum loads on the original unmodified asphalt used in paving process, some defects appear over time such as cracks and deformation of roads. This calls for work to improve the rheological properties of asphalt to produce asphalt paving more resistant to the factors above. This study focuses on the use of polymeric mixtures of consumed copolymers in asphalt modification processes. These polymers were thermally treated to find out the temperature at which they could be used in the modification process. Asphalt was treated with different percentages of sulfur as a catalyst under specific conditions of temperature and reaction time, during which the optimum catalyst ratio that can be used in the modification processes was determined. Asphalt was treated with a polymer mixture consisting of (ASA and SBS) (1:1) in different weight ratios with the presence of the optimum catalyst ratio and under the above reaction conditions. Several samples were obtained and the rheological properties of the original and modified asphalt were measured by penetration, softening point, ductility and penetration index calculation as well as calculating the weight percentage of asphaltene. The best sample obtained from the above modification process was determined, and reactions were performed on it again to determine the optimal temperature and reaction time, as well as to determine the optimal percentage of sulfur as a catalyst by measuring the rheological properties of the best sample. The best sample obtained in this study was (AS9), and to find out the suitability of this sample that was selected for paving process, the Marshall, chemical immersion and aging test as well as the field emission scanning electron microscope were performed. The modified sample gave better rheological properties and a resistance greater by 56% than the original asphalt when compared with the standard specifications approved in the field of paving.