Bitumen is a typical low-cost thermoplastic that has a wide variety of applications in construction and engineering. However, bitumen has poor mechanical properties, being hard and brittle in cold temperatures and soft and fluid in hot temperatures. Blending bitumen with synthetic polymers, either virgin or waste polymer, is one of the many ways to toughen it.
Polymers, such as thermoplastic, thermo hardening, and elastomeric polymers, are the only materials that have shown a real ability to enhance all of the necessary properties. Bitumen emulsion is a combination of fine bitumen droplets and water. However, since bitumen is a petroleum product, it does not blend with water and, because of its sticky nature, it is difficult to disintegrate into fine droplets. Cutback bitumen refers to a group of binders made by combining penetration grade bitumen with a hydrocarbon solvent like paraffin or mineral turpentine.
The primary objective of bitumen modification for use in structural layers is to enhance these layers' resistance to permanent deformation at high road temperatures without losing their properties over the rest of the temperature range.
- As tyre pressures, axle loads, and traffic volumes rise, the use of polymer modified bitumen to improve performance is becoming more common.
- Improving performance can be accomplished in two ways, both of which help to reduce long-term stress:
- • An increase in the elastic component with a corresponding decrease in the viscous component; and bitumen stiffening to minimize the layer's total viscoelastic response.
In terms of volume, Asia Pacific is projected to be the fastest-growing region, with a CAGR of 3.0 percent expected from 2016 to 2024. Over the forecast era, government measures to develop roads to reach rural areas are expected to push up demand for bitumen. As a whole there is a good scope for new entrepreneur to invest in this business.