The thermal degradation of the acrylonitrile-butadiene-styrene copolymer (ABS) was carried out at different temperatures from 360 to 440 degrees C in static and dynamic atmospheres of nitrogen, using semibatch operation. Nitrogen-containing compounds were found in all three degradation fractions: gases (as NH3 and HCN), oil, and residue. The percentage of the oil fraction increases with the increase of the degradation temperature. At 440 degrees C 63 wt % of the initial ABS feed was recovered in the oil fraction. The nitrogen (N) concentration of the oil fraction was in the range of 29-40 mg/mL. 4-Phenylbutyronitrile is the main N-containing degradation product (16-19 wt % in oil). N-compounds were also found as aliphatic and aromatic nitriles, amino derivatives, and heterocyclic compounds containing one or two N atoms such as pyridine, pyrimidine, and quinoline. Dynamic atmospheres of nitrogen and the residence time of the products in the reactor affects the oil recovery rate and the distribution of N in the degradation products.