A Thorough Study on the Molecular Weight Distribution in Natural Asphalts by Gel Permeation Chromatography (GPC): The Case of Trinidad Lake Asphalt and Asphalt Ridge Bitumen

The roadway performance is chiefly governed by the chemical composition of asphalt, which in turn depends on the molecular weight distribution in this product. Gel permeation chromatography is one of the most powerful and convenient analytical technique available for characterizing the entire molecular weight distribution of a bitumen. Molecular weight and polydispersity of two natural asphalts viz. Trinidad Lake asphalt (TLA) and Asphalt Ridge bitumen (ARB) have been determined. The number average molecular weight (Mn) of TLA was 893, whereas that of ARB was 993. It is predicted that TLA will deliver a smoother and higher-quality pavement than does ARB.