What is bitumen

What is bitumen? 

A colloid compound consisting of several components. The main components are bitumen, asphaltene, and maltene. In this colloidal system, highly polar, heavy, and interconnected asphaltene molecules are suspended and dispersed in the oily environment of maltene solvent. Maltene is a continuous phase constituted of saturates, aromatics, and resins. Carbon and hydrogen are the two main constituents of hydrocarbons in petroleum asphalts, where other elements such as oxygen, sulfur, nitrogen, and small amounts of other metal can be found.  
Hydrocarbons that can be found in non-petroleum compounds abundantly can affect all physical, chemical, and mechanical characteristics, and consequently the behavior of the bitumen. Each of the main compounds of bitumen will influence the features and performance of the bitumen. Generally, the chemical and physical properties of the bitumen can be evaluated from the resultant effect of these compounds with regards to their quantitative ratios, which is different in every type of bitumen. For instance, asphaltene increases the hardness of the bitumen, while maltene will give it adhesion and ductility. Maltene can also affect the viscosity of the bitumen.