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The aim of this work is to investigate the degradation of low molar mass poly(ethylene terephthalate) (PET)/organically modified montmorillonite (OMMT) clay nanocomposites prepared by melt processing. The rheological behavior in combination with transmission electron microscopic images suggests an intercalation and therefore a percolating network. Furthermore, the results indicate that the increase of organoclay content caused a degradation of PET during processing of PET/OMMT nanocomposites, once it was observed the PET molar mass decreases. The effect mentioned could be attributed to an increase of Brønsted acidic sites on the platelet surface, which is produced by the Hofmann elimination reaction of ammonium, and also the presence of residual metal compounds on clay surface might possibly favored the polymer matrix degradation process.

The purpose of this dissertation is to analyze Philip Pettit's republican theory of justice. This demands, initially, the development of his conception of freedom as nondomination, which is central to his republicanism. From this conception of freedom, it's possible to develop a republican conception of justice, which allows us to design institutions encharged of maximizing non-domination on the relationships between citizens and between these citizens and the state. Regarding the relationship between citizens, Pettit develops domestic institutions on the domains of infrastructure, insurance, and insulation. And regarding the relationship between the people and the state, Pettit builds a republican theory of democracy, which has a system of participation and contestation. Besides this, we also believe that Pettit's theory of justice, in order to prove its relevance on the contemporary normative political theory, needs to be compared with John Rawls liberal-egalitarianism, a doctrine that has a prominent site on this debate. Therefore, we stand up for Philip Pettit's republicanism as a alternative to the Rawlsian republicanism, but also stress some problematic issues on the work of the former.