Phase-Destabilization Mechanism of Polymer-Modified Bitumens in Quiescent Annealing

Bitumen as a binder in coating and insulating materials is modified withpolymers to improve its performance in service conditions. almost allpolymers are incompatible with bitumen, and at high temperatures dueto relatively very low viscosity of the bitumen phase, are separated from it. theselead to a considerable limitation in the use and handling of polymer-modifiedbitumens. an understanding of the mechanisms of phase separation of theseincompatible mixtures help to improve methods of transportation and handlingof polymer-modified bitumens. according to direct observations of the behaviorof polyethylene particles in medium of molten bitumen confirm the indirectconclusion already made by others, (coalescence based phase separation) andreject any possibility of occurring ostwald ripening. this conclusion can alsogeneralized to viscoelastic incompatible polymer blends. prog. color colorantscoat. 2(2009), 53-59. © institute for color science and technology