olecular Level
Extensive research on petroleum composition at the molecular level
has been done by many workers for many years. At this point, much of it
is essentially textbook material but worth reviewing here.
2.1.1 Typical Species in Virqin Asphalt. At the molecular level
most of the total mass of neat (tank) asphalt is a mixture of a wide
variety of high boiling hydrocarbons. Some are aliphatic (waxy
materials), some are aromatic (more like air-blown asphalts) and some
molecules have both aliphatic and aromatic carbon. Examples of such
molecular fragments are shown in Structures 1 (aliphatic type) and 2
(aromatic type