Improving the rheological properties of crumb rubber modified binder using hydrogen peroxide

• Published in: Road materials and pavement design Vol. 14; no. 3; pp. 723 - 734
• Main Authors: Shatanawi, Khaldoun M., Biro, Szabolcs, Naser, Mohammad, Amirkhanian, Serji N.
• Format: Journal Article
• Language: English
• Published: Paris Taylor & Francis 01.09.2013; Lavoisier
• Subjects: Applied sciences; Asphalt; asphalt rubber; bitumen; Bitumen. Tars. Bituminous binders and bituminous concretes; Buildings. Public works; crumb rubber; Exact sciences and technology; hydrogen peroxide; Materials; Recycling; rheology; Rubber; segregation; stability; Strength of materials (elasticity, plasticity, buckling, etc.); Structural analysis. Stresses; Tires; Temperature; Hydrogen peroxide; Stability; rheology; Molecular weight distribution; Segregation; Construction materials; bitumen; Experimental study; Gel permeation chromatography; Polymer modified asphalt; Asphalt; crumb rubber; Test method; Properties of materials; Rubber; asphalt rubber; Aggregate(materials); Rheological properties
• ISSN: 1468-0629; 2164-7402
• DOI: 10.1080/14680629.2013.812535

To overcome the problems of segregation between the rubber particles and the asphalt binder in the crumb rubber modified asphalts (CRMAs) different solutions were tested, including the establishment of chemical bonds between the different components of CRMA and the asphalt materials. In this research, a chemical method was employed to treat variously manufactured (ambient and cryogenic grinded) crumb rubbers' surfaces in order to graft functional groups and improve bitumen-rubber compatibility and reduce segregation. In general, 400 g of crumb rubber was heated to 80±2°C and was continuously stirred with 100.1 ml of hydrogen peroxide and 90.1 ml of FeSO 4 for 30 min. Then the activated crumb rubber was processed into asphalt for 60 min at 177±2°C. Hydrogen peroxide treatment significantly reduced phase separation; it produced even more stable suspension when FeSO 4 catalyst was employed. The surface differences of cryogenic and ambient grinded rubbers resulted differences in the flow properties, especially in shear elasticity.