CONTRIBUTION OF GEL PERMEATION CHROMATOGRAPHY (G.P.C.) TO THE QUALITATIVE AND QUANTITATIVE CHARACTERIZATION OF ASPHALTS. COLLOIDAL STRUCTURE

CONTRIBUTION DE LA CHROMATOGRAPHIE SUR GEL PERMEABLE (G.P.C.) A LA CARACTERISATION QUALITATIVE ET QUANTITATIVE DES BITUMES. STRUCTURE COLLOIDALE

In this paper is a report on the application of G.P.C. on micro-packing to the characterization of bituminous binders. This method is shown to provide, in less than ten minutes, an accurate and reproducible figure of the apparent repartition of molecular size of constitutive entities of the binder. It has been found that straight run distilled asphalts, and especially their asphaltenes, give bimodal distributions whereas in air-blown asphalts, a third population appears systematically which is located towards the large molecule sizes. The study of the problems posed by quantitative interpretation reveals the need to corect the response of the detectors. It has been shown that correction curves depend largely on the detector type (differential refractometer and ultraviolet detector) but hardly on asphalt. For several asphalts a calibration curve has been established which relates the number average molecular weight to the elution volume. The curves are fairly superposable and provide a means curve independent of crude origin and production process. The micellar behaviour of asphalts fractions solutions is shown up by viscossimetry. According to this method the concentration below which micelle dissociation occurs is located at about 2-5 g/1. The number aveage molecular weights provided by vapor pressure osmometry are in good agreement with those computed from G.P.C. curves. For weight average molecular weights, the values are overestimated by comparison with those really accounted for by G.P.C. because of dissociation phenomena in dilute solution and underestimated with regard to actual weights in the associated state. /Author/

  • Corporate Authors:

    Central Laboratory of Bridges & Highways, France

    75732 Paris,   France 
  • Authors:
    • BRULE, B
  • Publication Date: 1978-3

Language

  • French

Media Info

  • Features: Figures; References; Tables;
  • Pagination: 73 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00190175
  • Record Type: Publication
  • Source Agency: Central Laboratory of Bridges & Highways, France
  • Report/Paper Numbers: Research Report 76
  • Files: TRIS
  • Created Date: May 26 1979 12:00AM