Home – Home – Jornals – Chemistry for Sustainable Development 2016 number 1

Modifiers of the properties of petroleum paving bitumen were developed on the basis of two kinds of acryl-nitrile rubbers BNKSС-18 AM (TU 38.30313-2006) and BNKS-28 AM (TU 38.30313-2006) and the fraction of liquid products of tyre pyrolysis without access of the air, with boiling point above 170 °C. Rubber content in the mixture did not exceed 30 mass %, the temperature of mechanical homogenization was 100-120 °C duration was 3 h. Preliminary studies showed that the mixtures prepared under these conditions do not get separated into phases when kept hot for 6 h. Addition of a modifier in the amount of 3-5 mass % per rubber improves the elasticity of bitumen and, which is especially important, causes a substantial decrease in brittle temperature. Due to this, resistance of paving asphalt concrete to frost and to cracks increases substantially. The composition of the fraction of liquid products of tyre pyrolysis was determined by means of IR spectroscopy and gas chromatography-mass spectrometry. This composition includes more than 100 individual compounds with content >0.1 % of the sum of all detectable peaks. These substances are represented mainly by aromatic hydrocarbons, mainly the derivatives of benzene and naphthalene containing aliphatic fragments with total number of carbon atoms 4 to 10 as substituents (43 rel. %). In addition, hydrocarbons with menthene structure were detected (31 rel. %), and aliphatic acyclic hydrocarbons with chains containing 16 to 27 carbon atoms (18 rel. %). Nitrogen-containing compounds are represented by hexahydro-2Н-azerin-2-one (caprolactam) - 0.5 rel. %, as well as 1,2,3-benzotriazol - 0.9 rel. %.