Protection on the road
Road markings ensure traffic safety. But there are differences among them—in terms of quality and eco-friendliness. Evonik has conducted an independent life cycle assessment for its product, which already has decades of success behind it, and found that DEGAROUTE®-based road markings protect not only road users but also the climate.
They shine like gems: tiny glass beads embedded in the road marking material reflect the light from headlights in dark or wet conditions. This is why the markings are still so easy to see in the dark, the fog and the rain. Which means greater safety. Thanks to their structure, the lines and surfaces are extremely durable as well.
Various systems can be used to apply these kinds of structured, three-dimensional markings to roads. One of these is cold-plastic marking based on DEGAROUTE® reaction resin from Evonik Industries. DEGAROUTE® has proven itself in this application for over 50 years, the quality of the product having long produced impressive results. Lately, however, it is not just safety but the environmental aspect that is playing a more important role. Increasing traffic volumes call for more and more markings—but not at the expense of the environment.
Environmental impact study
For this reason, Evonik compared its DEGAROUTE®-based road markings with three other common road marking systems: hotspray plastic, solvent-based paint and water-based paint. The specialty chemicals company studied all four systems as part of a comprehensive life cycle assessment (LCA). An LCA is a systematic tool that analyzes the influence a product has on the environment over its entire lifespan. It takes account of the entire valueadded chain, from the raw materials, through production and application, to disposal or recycling. It even includes transport and packaging materials.
In this case, Evonik studied a two-lane, one-kilometer section of roadway equipped with a middle stripe and two edge stripes. The assessment period was ten years—after this time roads normally have to be resurfaced. Depending on the technology used, the markings have to be renewed at different times in this period.
According to the results of the LCA study, cold-spray plastic with DEGAROUTE® is far superior to the other technologies. It obtained the best results, thanks to its longevity in particular. The study showed that, more than anything, the service life of a marking is key to its environmental impact. And in this respect, the solvent- and water-based systems came off second-best. Over the period of the study, the solvent-based paint had to be reapplied ten times to obtain the marking, while DEGAROUTE®-based cold-spray plastic had to be reapplied only four times. Hotspray plastic did similarly well in terms of longevity, but it consumed more material.
This high durability is primarily a result of the glass beads contained in the marking material. According to the LCA study, durability is also the deciding factor for CO2 emissions and, therefore, the global warming potential of the individual systems. Hot-spray plastic has a 50 percent higher warming potential than DEGAROUTE®-based cold-spray plastic with glass beads, and paint systems are roughly 80 percent higher. In comparison, the application step accounts for only a small percentage of the global warming potential—with the exception of hot-spray plastic, which has to be applied in a melted state at high temperatures, and requires the use of gas burners.
Using DEGAROUTE® in combination with glass beads ensures a long useful life and, therefore, a good life cycle assessment. "DEGAROUTE®-based cold-plastic markings display superior quality and resistance," says Dr. Harald Guder, managing director of Limburger Lackfabrik GmbH, Germany's leading manufacturer of road marking materials. "Particularly when it comes to heavily traveled sections of roadway, such as intersections and main roads, the useful life of cold plastic is impressive." But DEGAROUTE® cold plastic has another point in its favor: it cures very quickly and can therefore be applied in free-flow traffic. "This prevents traffic jams and eliminates the need for closing off sections of road to create detours," says Guder, a road marking specialist. "And because cold-plastic markings have to be re-applied less often than other systems, less intervention in traffic is necessary." All this adds up to reduced CO2 emissions.
So while the more durable cold- and hot-spray plastic systems are proving themselves to be resource-efficient solutions wherever traffic is high, paint systems are a good alternative for areas with less traffic.
The LCA study was conducted in accordance with ISO 14040 and critically reviewed by independent experts from industry, science and research: the University of Stuttgart, the LCA specialist PE International, a recognized marking expert, and a worldwide leading provider of road markings certified that the study reflects the highest scientific quality and objectivity. In early 2012, the system was certified to ISO 14044.