Resumo

PAMPLONA, Thaís F. et al. Asphalt binders modified by SBS and SBS/nanoclays: effect on rheological properties. J. Braz. Chem. Soc. [online]. 2012, vol.23, n.4, pp. 639-647. ISSN 0103-5053.  http://dx.doi.org/10.1590/S0103-50532012000400008.

In this work, it was investigated the effect of organically modified vermiculite and montmorillonite (OVMT and OMMT, respectively) in asphalt binders (AB) modified by SBS (styrene-butadiene-styrene). The physical and rheological properties were performed for AB, 4.0% SBS MB and nanocomposite AB modified by 2.5% SBS with 2.5% of organoclays. The modified binders (MB) result in the enhancement of complex modulus (G*) and reduction of phase angle (d), which means greater resistance to permanent deformation. The viscosity, penetration and thermal susceptibility were appropriate. The black diagrams show that the effect of nanoclays OVMT and OMMT was similar to the effect of Cloisite^®. The rheological properties of the nanocomposite were comparable to the 4.0% SBS MB, identifying a cost reduction due to the potential of replacing polymer with clay. The presence of OVMT improved the storage stability of SBS MB, an important result, as the phase separation is a major obstacle to the use of SBS in paving.

Palavras-chave : asphalt binder; SBS; montmorillonite; vermiculite; rheology.