Stability measuring dust tires bitumen solubility in organic solvents

Antonio Perez Lepe
Antonio Páez Dueñas
Technology Management
Repsol YPF

ABSTRACT
Modification wet bitumen with crumb rubber (PNFU) produces, in most cases, highly unstable systems due, among other causes, to the rubber bitumen incompatibility vulcanized, heterogeneity and the presence of solids in the scrap rubber . The stability criteria commonly used consists of storing a sample tube at high temperature (163ºC; 5 days) and observing the variation in penetration and softening temperature between the top and bottom of the tube part. The use of certain additives in the formulations of rubber bitumen can mask stability data showing binding as a stable high solids decanted. using a more stringent method, which measures both the solids content and the state of the vulcanized rubber it is proposed in this paper. By a measure solubility you can determine the amount of insoluble unincorporated or effectively anchored to the bitumen material. This method has been applied to various formulations of modified binders crumb rubber and other additives widely studying the stability of such systems. Indeed, how stable binding it is observed from the viewpoint of penetration and softening temperature, they present problems of solids settling and heterogeneity during manufacture and application.

Keywords
Bitumen, tires, wet, tire out of use, NFU, stability.