The dissertation work is devoted to the decision of an actual problem – obtaining of the high-quality road bitumens steady against technological aging. The use of the proposed modified petroleum bitumens, which demonstrateimproved resistance to aging processes that take place at the technological stage, is one of the ways to help extend the service life of the roadway. Given that most Ukrainian bitumens are made from paraffinic and high-paraffinic oils, which differ in their properties from oils that serve as raw materials for the production of bitumen in the world, obtaining an aging binder for Ukrainian roads is especially important. In the process of dissertation research on the basis of existing domestic and foreign experience, the main patterns observed in the aging process were studied, priority areas of research were identified and ways to solve the existing problem were proposed. Given the known laboratory methods of modeling the aging process of the binder, it was proposed to compare the modified method of heating in a stationary layer, derived from the standard method for determining resistance to hardening under heat and RTFOT method to determine resistance to hardening in dynamic mode. The analysis of the obtained results revealed that the use of the RTFOT method contributes to the creation of conditions more closer to those that occur during the preparation and laying of the asphalt concrete mixture. At the same time, the heating of thin bituminous films in the stationary layer, which was carried out for 5 and 10 hours, allowed to clearly separate the stages in which the most active transformations of the mixture components take place. Using these techniques, the study of oxidized and distilled samples of bitumen were carried out and the main differences observed are described. In addition to changes in the most important indicators, the results were confirmed by infrared spectroscopy, derivatographic studies and changes in group composition. Further dissertation research was aimed at studying the effect of modifiers of different classes on their ability to slow down the aging process. In particular, the following were studied as inhibitors of aging: hydrocarbon pyrolysis products (petroleum polymer resins with functional groups and heavy pyrolysis resin); resins obtained from liquid products of coal processing; technical sulfur; crumb rubber and salts of humic acids. It was found that the modification of oxidized bitumen petroleum resins with hydroxy groups in the amount of 5% wt. due to the decrease of the softening temperature after heating and loss of volatile components is also insignificant. The disadvantage of using PR (H) is a significant increase in the hardness of the samples. The use of petroleum resins with carboxy groups leads to a significant increase in the hardness of the obtained sample and greater evaporation of volatile components. That mean, that use of PR (oil petroleum resins) as an inhibitor of oxidized bitumen is impractical. Another situation is observed with the use of these resins as inhibitors of distillated bitumen. Moderate change of properties in the process of heating the distillated bitumen with the addition of PR (H) allows to recommend this compound to slow down the aging process. The use of heavy pyrolysis resin in the amount of 5 % wt. demonstrates resistance to hardening of the modified sample for both oxidized bitumen and distilled. The addition of phenol-cresol-formaldehyde resin obtained from liquid products of coal processing, as well as a complex bitumen-polymer composition based on it, does not allow to obtain a binder sufficiently resistant to technological aging. The results obtained with the use of technical sulfur are also unsatisfactory. Crumb rubber modification was performed for 2 hours at 160 °C to prevent ] binder degradation. The obtained sample of oxidized bitumen with a crumb rubber content of 8 % wt. demonstrated a slight loss of properties during heating, while the addition of crumb rubber to the distilled bitumen revealed insufficient slowing down of the respective processes, in addition, the initial composition of the mixture needed to be improved. Of all the modifiers, the introduction of potassium humate demonstrate the best effect on deceleration the aging process. In addition, the most optimal should be considered the following concentrations: 5 % wt. potassium humate with a humic acid content of 80 % wt. and 3 % wt. potassium humate with a humic acid content of 85 % wt. - for oxidized bitumen, as well as 1-3 % wt. potassium humate with a content of humic acids of 85 % wt. - for distilled bitumen. Another advantage of using this compound is that the mixing of potassium humate with bitumen takes place at a temperature not exceeding 130 °C, which in turn prevents premature loss of binder properties.
