A study into the processing of bitumen modified with tire crumb rubber and polymeric additives

This work focuses on the influence that processing variables (such as gap between rotor and stator of the mixer, time and temperature) exert on both mechanical properties and hot storage stability of bitumen modified with crumb tire rubber and polymeric additives, with the aim of optimizing the formulation of bitumen modified with low solubility materials.The experimental results obtained reveal that all the polymeric additives used yield an improvement in both the rheological and technological properties of the binder. Processing time leads to an increase in both the primary aging and rubber digestion, with the latter effect predominant for times of up to 2–3 h. Processing temperature increases the amount of rubber digestion and improves the elasticity of the resulting binder.

► Optimized formulation of bitumen modified with low solubility materials is desired.
► Influence of processing conditions on thermomechanical properties is analyzed.
► Elasticity and rubber digestion are improves with temperature and time.
► Gap between rotor and stator hold little influence on the amount of rubber digestion.
► Increase in viscosity due to aging and decrease in mechanical properties above 200 °C.