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Handbook of Size Exclusion Chromatography and Related ...

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8<br />

<strong>Size</strong> <strong>Exclusion</strong><br />

<strong>Chromatography</strong> <strong>of</strong><br />

Asphalts<br />

Richard R. Davison, Charles J. Glover, Barry L. Burr, <strong>and</strong><br />

Jerry A. Bullin<br />

Texas A&M University<br />

College Station, Texas, U.S.A.<br />

1 INTRODUCTION<br />

Early researchers in the application <strong>of</strong> size exclusion chromatography (SEC) to<br />

asphalt (1–7) noted that size exclusion chromatography (SEC) [also called gel<br />

permeation chromatography (GPC)] was very sensitive to differences in asphalts<br />

<strong>and</strong> to changes in composition. This was exploited by Adams <strong>and</strong> Holmgreen (8)<br />

to show differences between various asphalts <strong>and</strong> between asphalts from the same<br />

supplier at different locations. Glover et al. (9,10) used SEC to show how asphalts<br />

from a number <strong>of</strong> suppliers changed with the seasons. It has also been used to<br />

compare fractions produced by preparative SEC <strong>and</strong> other methods (9,11–24).<br />

SEC can be quite sensitive to contamination by material <strong>of</strong> low molecular<br />

weight or narrow molecular weight distribution. This was used by Burr et al. (25)<br />

to prove incomplete solvent removal by st<strong>and</strong>ard American Society for Testing <strong>and</strong><br />

Materials (ASTM) extraction <strong>and</strong> recovery procedures.<br />

Bynum <strong>and</strong> Traxler (4) were the first to use SEC to study road aging. SEC is<br />

very sensitive to the changes that occur when an asphalt hardens. Minshull (5) <strong>and</strong><br />

© 2004 by Marcel Dekker, Inc.

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