Avaliação reológica do ligante asfáltico modificado com nanopartículas de óxido de zinco.

Abstract

In order to minimize premature deterioration of asphalt coatings, the use of modified binders by nanomaterials has grown, since traditional modifiers (e.g. polymers, rubbers, fillers) have limitations on the ability to improvements performance (increased lifespan, resistance to permanent deformation). Zinc oxide (ZnO) is a chemical accelerator activator, UV absorber, used as an additive in various materials and products (such as rubber, cement, lubricants) and its introduction has recently been studied in asphalt mixtures. The objective of this research was to evaluate the effect of the incorporation of 3, 5 and 7% of zinc oxide nanoparticles, unmodified (ZnO) and surface modified (ZnO M) by silane agent, in the asphalt binder (CAP 50/70). It is composed of 04 stages: synthesis of the ZnO nanoparticles, chemical analysis of the binders by means of Fourier transform infrared spectroscopy (FTIR), physical (penetration and softening point) and rheological tests (rotational viscosity, performance grade (PG), multiple stress creep recovery (MSCR), linear amplitude sweep (LAS) and master curve). The results indicated that the addition of ZnO nanoparticles increased PG, fatigue life and resistance to permanent deformation of the binder, mainly with the addition of 7% ZnO, indicating the technical feasibility of this modification to the asphalt binder CAP 50/70. Binders with ZnO M presented similar results, but in smaller scales. In addition, they increased the resistance of the modified binders to the short-term aging RTFO, providing benefits to the binder studied.