The first patent for modifying bitumen with natural rubber was registered almost 170 years ago. Ironically, it took another 150 years before the modified road bitumen has taken a worthy place in road construction.
There were a couple of reasons for this.. Firstly, the traffic loads on roadway are ever-increasing. Secondly, large polymeric materials are available.
Natural rubber, as the first modifier of road bitumen dispersed well. It’s problem was foaming, but it could be controlled by the way it was added.
Other polymers took some time to become available. Approximately 30-40 years ago first new modification additives came into the market. They have necessary solubility and structure, and good rheological and mechanical properties. According to experts, to date, polymer modified bitumen covers 10% of total consumption of bitumen, making it 10 million tones.
Overall, the preliminary cost of asphalt preparation with modified road bitumen is greater than cost for conventional asphalt. So there is an urgent search for cheap modifying additives. Over the past few years the following solutions have been proposed – the use of:
- Polymers from waste;
- Used rubber tires;
- Wax additives;
Rheology modifiers (i.e. polyphosphoric acid).
Each of these methods has its advantages and disadvantages, so the decision to use a particular additive should be taken individually.
For a successful and cost-effective modification – polymers must meet the following requirements:
- Form three-dimensional network in the polymer phase;
- Good interaction with road bitumen for significant absorptionFor implementation of polymer modified bitumen in road construction GlobeCore produces UVB-2 installation. This equipment:
- Works with all known to date, polymers, waxes and various specific additives;
- Uses any form of modifiers : powders, granules, etc .;
- Realizes any formula for bitumen modification;
- Adds plasticizing agents during the modifying process;
- Adding extra polymer during transfer mode;
- Reduces electrical bill with oil heating system.