Bitumen is black semi solid heavy hydrocarbon which by cool done of ambient temperature will convert to solid. With increase of temperature the bitumen will become semi solid and then liquid. Main content of bitumen us hydrocarbon with high molecular weight contenting oil, resin and asphalten.

bitumen penetration grades are hard penetration grade bitumen using as paving grade bitumen

suitable for road repair and  construction  also for the production of asphalt pavements with below

technical specification. This grade of bitumen is mainly used in the manufacture of hot mix

itumen has been used for thousands of years and its importance as a valued engineering material continues to increase. The interest in the modification of bitumen using polymers, whether virgin, scrap or polymer blends, is intense. The last two decades, in particular, have seen an increase in the number of academic groups studying polymer-modified bitumen and correspondingly the peer-reviewed literature in the field has increased. Initially, studies on polymer modified bitumen focused more on engineering and empirical measurements, e.g. ageing and softening point. However, in recent years a plethora of techniques have been employed in the study of the effect of the addition of polymers on a range of bitumen properties, polymer_bitumen morphology and polymer_bitumen interactions.