| PPA Modified Asphalt |
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| Written by Szabolcs Biro |
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Studies have shown that PG grade of the asphalt binder tends to increase with the addition of PPA. This increase has been attributed to the stiffening of one of the two main phases in the asphalt. This study indicated that the stiffening effects were base binder dependent. However, the following mechanisms were proposed to explain the stiffening of the PPA modified asphalt: formation of PPA aducts, alkylation of aromatics, cross linking of neighboring asphalt segments, formation of ionic clusters and the cyclization of alkyl aromatics.
 Furthermore, it has been suggested that the addition of PPA to asphalt contributes to more interactions within the asphaltenes network, thus increasing the elastic behaviour. This occurs through the increases in the complex modulus values (G*) and decreases in the phase angle (d). Typically the amount of PPA added to asphalt binder is between 0.5 -1.5%, resulting in a PG grade increase of the asphalt binder.
Additional benefits of PPA modification include its suitability for use with other polymers. Studies have shown that PPA can successfully substitute for partial quantities of SBS. Thus, it provides economical solutions for reaching desired performance grades. ECOPATH has extensive experience in binder design where emphasis is placed on achieving specified binder in the most cost effective manner. ECOPATH provides unique solutions for every asphalt concern, moreover ECOPATH is dedicated to developing solutions with economic efficiency as a priority. Please contact us for further information on binder design services. |
| Last Updated ( Tuesday, 30 June 2009 18:33 ) |
The addition of PPA has long been known to increase the performance grade (PG) of the asphalt binder. Many studies have shown that appropriate introduction and dosing of PPA into asphalt binder can yield cost effective solutions which translate to improved performance properties.