This article presents the results of the synthesis and morphological characterization of carbon nanostructures obtained from the decomposition of residual solid from waste tires (RSWT) in quartz tubes under reduced pressure (1.33 Pa) at 900°C for 15 min. The synthesis led to the formation of two phases, a fragmented solid black powder composed of multi‐walled carbon nanotubes (MWCNTs), onion‐type fullerenes, and spheres, and a very bright metallic dark film. Analysis by microscopy (SEM and TEM) showed that the MWCNTs had an average diameter of approximately 25 nm and a length greater than 100 nm while the diameter of the onion‐type fullerenes was found to be 8 nm. The nanospheres showed different diameters ranging from 500 nm to 1.5 μm, and some had a metallic core surrounded by layers of carbon. The infrared spectra of the nanotubes exhibited absorption bands at 1558 and 1458 cm−1, corresponding to CC and CC bonds, and signals at 3438 and 1080 cm−1 related to the OH and CO groups from oxidized graphite as it was identified in the dark film. The Raman spectra of the carbon nanostructures present D and G‐bands at 1331 and 1597 cm−1, respectively. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012