The effect of asphaltene on thermal properties of bitumen

Chemical composition and any variation of four main components of bitumen (asphaltene, saturated, naphthene aromatic and polar aromatic) have effective impact on its properties and especially, thermal properties. In other words, in order to have asphalt pavements with reasonable temperature susceptibility and thermal stability, first of all it is essential to know the effect of these components on bitumen properties. Therefore, in this research these effects were investigated and it was found that penetration index (PI) and penetration viscosity number (PVN) of bitumen were increased with increasing in asphaltene content.Thermal behavior of bitumen in an oxidizing environment was also studied using thermogravimetric analysis (TGA) technique. The results showed that increasing the asphaltene content of bitumen decreases the temperature susceptibility and improves the resistance of samples to thermal decomposition.

Research highlights
► The effect of bitumen components on its thermal stability were studied.
► Increasing the asphaltene content of bitumen will increase the penetration index.
► Increasing the asphaltene content will increase the penetration viscosity number.
► Increasing the asphaltene content decreases the temperature susceptibility.
► Increasing the thermal stability improves the resistance to thermal decomposition.