Abstract
This paper presents a study that uses gel permeation chromatography (GPC) to characterize the aging process of blends of aged crumb rubber-modified (CRM) binders containing rejuvenating agents. Two aging processes proposed by SHRP binder specifications - rolling thin-film oven (RTFO) and RTFO + pressure-aging vessel (PAY) - were used for the aging of the blends. The GPC profiles-namely, the molecular size distributions-of the blends of aged binders and rejuvenating agents were measured by GPC, and different molecular sizes of these blends were calculated. Three aged CRM binders and two aged control binders of PG76-22 (3% styrene-butadiene-styrene-modified binders) were mixed with several percentages of either a rejuvenator or a softer binder to produce the blends. In addition, performance properties of these blends at three different aging states - that is, no aging, RTFO aging, and PAY aging-were tested and correlated with the larger molecular sizes of the GPC results. It was concluded that compositional changes of these blends due to the RTFO and RTFO+PAV aging processes were well reflected by GPC results. In addition, correlations between the large molecular size and the performance properties of the blends are rather good.
| Original language | English |
|---|---|
| Title of host publication | Bituminous Materials and Nonbituminous Components of Bituminous Paving Mixtures 2006 |
| Publisher | National Research Council |
| Pages | 21-27 |
| Number of pages | 7 |
| Edition | 1962 |
| ISBN (Print) | 0309099714, 9780309099714 |
| DOIs | |
| State | Published - 2006 |