The Effect of Mixing Procedure on Rheology and Morphology of Bitumen Modified by Polybutadiene –Nanoclay

A 60/70 penetration grade bitumen was modified by incorporating a combination of high cis 1,4-Polybutadiene Rubber (PBR) and organophilic montmorillonit Closite 15A (C15A). Two procedures were employed to prepare the mixtures: 1) The three components PBR, C15A and Bitumen were loaded into a high shear mixer simultaneously; 2) Closite 15A was initially mixed with the rubber by using melt blending method and then obtained nanocomposite was blended with bitumen in the high shear mixer. The X-ray diffraction analysis results showed different structure with various level of intercalation for the mixtures prepared by the two mentioned procedures. Meanwhile morphological analysis by using florescence microscopy showed better dispersion of PBR in bitumen in presence of C15A. Rheological properties of nanocomposite modified bitumen were evaluated in linear viscoelastic region and higher complexmodulus and lower damping factor was observed for modified systems in compare with neat bitumen

کلیدواژه ها:

Rubber ، Modified Bitumen ، Rheology ، Morphology ، Organoclay