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Rubber from recycled car tires and styrene-butadiene-styrene (SBS) were used for the chemical modification of commercially available road bitumen 50/70 (EN 12591). The modification process began with the addition of rubber into asphalt and heating the whole amount at the temperature of 190 °C or 220 °C. Under such conditions, de-vulcanization of rubber took place. Next, SBS and sulfur as a cross-linker were added and the heating was continued so that cross-linking of SBS and the de-vulcanized rubber proceeded. In the studies on the influence of rubber concentration on the final properties of asphalt 10% or 15% of rubber was considered. Chemical modification reactions were performed within 2, 4, and 8 h. The results showed that both the modification at 190 °C and 220 °C affected the properties of the base asphalt efficiently, although the asphalt modified at 190 °C contained more non-degraded rubber. Increasing the modification time led to dissolution of the rubber crumbs and its de-vulcanization. Bitumens modified in this way are characterized by high storage stabilities. Their behavior at low temperatures also deserves attention.

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The asphalt mixtures rutting resistance depends on many factors connected to mineral composition and its characteristics, volume relationships, binder content and its properties. In the research program 15 samples of different binders were tested, 5 binders in stone matrix asphalt, 5 in asphalt concrete and 5 in high modulus asphalt concrete. The used binders were pure bituminous binder and PMBs with different amount of polymer. The binders' test program contained typical, conventional tests, as well as tests dedicated to Polymer Modified Binders. Finally, the three types of asphalt mixtures were tested at rutting test according EN 12697-22 specification. From the research it was concluded that there are a few relationships between specified binder properties and asphalt mixture characteristics. Among others the Multiple Stress Creep Recovery (MSCR) test results of samples tested at temperature related to rutting test temperature and viscosity are related to the rutting properties.