2020-02-112019-02-14OTUKI, Gabriela Fleith. Química forense aplicada em acidentes de trânsito. 2019. 65 f. Dissertação (Mestrado em Engenharia Química) - Universidade Federal de Alfenas, Poços de Caldas, 2019.https://repositorio.unifal-mg.edu.br/handle/123456789/1502The main objective of this study was to carry out analytical chemical studies on samples and traces of tires, with the purpose of assisting criminal investigations related to traffic accidents. In Chapter I, tire samples, in the marks A, B and C, were characterized by TG-DTG under inert atmosphere. Tire B was also characterized by TG-DTG in an oxidizing atmosphere. The thermogravimetry, using the inert atmosphere, was effective in determining the mass percentage of the thermal decomposition of the NR and SBR-BR rubbers of the tires A, B and C, being able to differentiate them. E, the use of the oxidizing atmosphere in the tire B sample determined the mass percentage of the decomposition of the NR, SBR-BR and carbon black rubbers. In the second chapter, samples of traces of tires, from real braking, performed at speeds of 60, 80 and 90 km/h, were collected and characterized by FTIR and TG-DTG. By means of the FTIR analysis, a differential in the intensity in the bands close to 1,076 cm-1 and 2,450 cm-1, related, respectively, with C-S-C and S-H cross-links could be observed. The sample with higher velocity presented higher intensity in both bands, and the sample related to lower velocity presented lower intensity in both bands as well. The thermogravimetric analysis showed that the mass residue of the 60 km/h sample was 17%, the sample of 80 km/h, 39% and the sample of 90 km/h, 45%. In this way, it was possible to differentiate samples of traces with different speeds. The result is possibly related to the number of cross-links in each sample and thus compatible with the FTIR result.application/pdfAcesso Abertohttp://creativecommons.org/licenses/by-nc-nd/4.0/Química legalAcidentes de trânsitoPolímerosProva pericialPneusENGENHARIAS::ENGENHARIA QUIMICADissertaçãoFurtado, Tatiana Cristina Mac Leod