Bitumen

Bitumen

Bitumen is a solid or resinous substance made of hydrocarbons and their derivatives in the form of nitrogenous, sulfurous, oxygenated and sulfur-containing compounds. The name comes from Latin bitumen, which means "mountain tar" and "asphalt".

The fractional (chemical) composition and characteristics of bitumen

carbon - no more than 80%;

hydrogen - no more than 15%;

sulfur, 2-9%;

oxygen, up to 5%;

nitrogen, up to 2%.

All substances in the composition by consistency are divided into 3 groups:

Solids. These include paraffins and hydrocarbon polymers (asphaltenes). Resins. Amorphous substances with a dark brown color. Oily. Hydrocarbon compounds with a density not exceeding 1000 kg/m3. Depending on the composition of bitumen may have different properties. If it is dominated by asphaltenes, the material becomes hard, but at the same time it becomes more brittle and begins to melt under the influence of high temperature.

Important characteristics and properties:

Density - 950 to 1500 kg/m3. Low thermal and electrical conductivity. Resistance to various chemical reagents. Water- and gas-tightness. No melting point (bitumen goes to liquid state at softening temperature).