Rheological evaluation of binder modified with Micronized Polyethylene Terephthalate (PET)

The performance of asphalt binder used neat was considered satisfactory until the end of 20 century. However, the increase of traffic and weather changes became necessary the use of additives to improve the properties of asphalt mixtures. Polyethylene terephthalate (PET) post-consumer micronized can be added in the traditional modified asphalt binders. With regarding to PET chemical, it is a long chain polymer, belonging to the generic family polyesters, and are formed from the intermediates, terephthalic acid (TPA) and ethylene glycol (EG). PET is then ground to a uniform particle size ranging from 0,6 to 0,074 mm. The chemical and physical characterization of the waste were performed according to ASTM D1921-9601 /2001 standards. The rheological tests were performed with pure samples of the binder and a mixture of the binder + PET. The content of PET was 5% by weight of the asphalt binder 50/70. Physical properties, such as dynamic rheological behavior, high temperature storage stability and aging properties of the modified asphalt were investigated. It was demonstrated that the modified binders outperformed the conventional binders at all the test conditions.