In this research project, the way in which a bitumen binder modified with polymers can be recovered without its properties being faded will be assessed. In complement, one will seek with which testing method a modification of the polymer modified binders can be clearly and easily proven. Moreover, the selection or the development of a suitable method to determine the solvent remainders is necessary. The main outcome of this research will be the development of a procedure for the recovering of polymer modified binders from mix samples and cores This method will be used as a basis for the revision of the standard SN 671 955 or for the establishment of a specific standard for the recovery of the polymer modified binders.
To develop an adequate method for recovering polymer modified binders from bituminous concrete cores.
The project includes the following activities:
Modified binder of the inventory used in Switzerland, existing recovery methods, the state of the art in recuperation binder, particularly polymeric binders, solvent and commercially available.
Selection of polymer bitumen categories, methods for recovering binder based on their ability to recover polymer bitumens and solvents depending upon their ability to dissolve the binder polymers considered and their impact on morphological and rheological properties of the binders.
3. Experience Map
Evaluation of the effect of recovery methods retained on the micro-morphological and rheological properties of selected binders. Overall rating results.
If necessary, some methods will be adapted to be better able to meet the needs (goals).
This will contain a proposal developing a polymer bitumen recovery process on samples of asphalt and tar coating. This method creates a basis for the revision of the standard SN 671 955 or for the establishment of a specific standard for recovery of polymer binders.
A study conducted jointly by the LAVOC and laboratory IMP Bautest for assessing the future CEN recovery method (VSS 1999-122 "Recovery of asphalt binder from extraction; Implementation and adaptation to the new European standard screws à-vis the Swiss experiment "report VSS 14/99) revealed the difficulties encountered during recovery of polymer binders. Using this method, it was found poorer repeatability and reproducibility of the results in the case of recovery of binder plastomers compared with the values obtained with a sample of elastomeric binders.
Another study by the LAVOC on the morphological evolution of modified binders in different stages of aging revealed:
- The problem of solvent; Indeed, depending on the type of solvent used there may be a significant change in the micromorphology of certain polymeric binders,
- The problem of the recovery method used; For some of them, it was found that at certain stages of the recovery, there is a change of the micromorphology of certain modified binders.