Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2016-06-01T18:48:34Z No. of bitstreams: 1 DIS_MATHEUS_SILVA_GIGANTE_COMPLETO.pdf: 954118 bytes, checksum: 553cbcaaa8e70eff331d2439adbd8c2c (MD5) / Made available in DSpace on 2016-06-01T18:48:34Z (GMT). No. of bitstreams: 1 DIS_MATHEUS_SILVA_GIGANTE_COMPLETO.pdf: 954118 bytes, checksum: 553cbcaaa8e70eff331d2439adbd8c2c (MD5) Previous issue date: 2014-03-31 / The availability of plastic bags for purchase packing began to popularize in Brazil during the ?80s. It is use, allied with a fast disposal and a slow decomposition results in a large accumulation in landfills, as well as rivers, lakes and seas. The understanding of these materials composition is essential for one to be able to assess the inherent risks involved in it is use and discartament. In this study, eight samples of plastic bags used for packaging were analyzed, being three of them derivated from naphtha, two from ethanol and the three were oxybiodegradable, in which a chemical additive is added to them so that it?s degradability time decreases. The technique of graphite furnace atomic absorption spectrometry was used to determine cadmium, lead, chromium and antimony. Thermal analyzes were also performed to evaluate the thermal stability and the melting temperature of the different types of samples. It was observed the presence of metals in plastic bags analyzed, and only the chromium could be identified in all samples. The metals and metalloids concentration varied between 0.013 and 2.7 ?g g-1, below the maximum limits established by legislation. Through thermal analysis used - thermogravimetric analysis and differential scanning calorimetry - it was observed that all the samples showed the same thermal behavior. Building up the data contents of metals and thermal analysis, it can be inferred that the presence of Cd, Cr, Pb and Sb did not influence the thermal stability of the polymers. / A disponibilidade de sacolas pl?sticas para embalar compras come?ou a se popularizar no Brasil nos anos 80. Seu grande uso, aliado ao r?pido descarte e a demora em se decompor resultam em um grande ac?mulo destas em aterros sanit?rios, bem como em rios, lagos e mares. Visando a redu??o do tempo de decomposi??o, diferentes materiais tem sido utilizados para a confec??o das mesmas. Nesse trabalho, foram analisadas oito amostras de sacolas pl?sticas utilizadas como embalagem sendo tr?s delas provenientes da nafta, outras duas do etanol e tr?s oxibiodegrad?veis (nas quais um aditivo qu?mico ? acrescentado a elas para que o tempo de degradabilidade diminua). Neste trabalho, a t?cnica de espectrometria de absor??o at?mica por forno de grafite foi utilizada para a determina??o de c?dmio, chumbo, antim?nio e cromo e as t?cnicas de an?lise t?rmica foram empregadas para avaliar as propriedades t?rmicas, bem como a temperatura de fus?o dos diferentes tipos de amostras de polietileno. Observou-se a presen?a de metais nas sacolas pl?sticas analisadas, sendo que apenas o cromo p?de ser identificado em todas as amostras. As concentra??es dos metais e metal?ides variaram entre 0,013 e 2,7 ?g g-1, ficando abaixo dos limites m?ximos estabelecidos pela legisla??o. Atrav?s das an?lises t?rmicas utilizadas - an?lise termogravim?trica e calorimetria diferencial explorat?ria - observou-se que as diferentes amostras apresentaram o mesmo comportamento t?rmico. Compilandose os dados de teores de metais e das an?lises t?rmicas, pode-se inferir que a presen?a de Cd, Cr, Pb e Sb n?o influenciou na estabilidade t?rmica dos pol?meros.