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- ItemAcesso aberto (Open Access)Síntese e utilização de zeólitas A, X e Y em tintas de poliaspártico(Universidade Federal de São Paulo (UNIFESP), 2020-02-19) Machado, Max Pimentel Da Matta [UNIFESP]; Bresolin, Igor Tadeu Lazzarotto [UNIFESP]; Universidade Federal de São PauloThe polyaspartic coating, one of the most innovative resins for the production of high performance paints, studying the effect of the addition of selected zeolites as adsorbents to remove moisture in the system. Polyaspartic is based on the reaction of an aliphatic polyisocyanate and polyaspartic ester which is an aliphatic secondary diamine. Beyond that reaction, polyisocyanates also react with water resulting in formation of polyurea and carbon dioxide. The water in the system comes from the other raw materials involved in the preparation of the coating such as pigments and additives. This reaction damages the polyaspartic system due to that speeds up the reaction significantly, what decreases the time limit for application of the coating. In previous works, some alternatives were determined to remove this moisture and the strategy that presented the best efficiency was using zeolite 3A for the adsorption of the water in the system. However, it was not found a work in the literature that compares the performance of zeolites of types A, X and Y with this purpose. Thus, the objective of this work was to modify commercial LTA zeolite, producing the zeolites 3A, 4A and 5A, to synthesize the zeolite Y using methods previously tested in the literature and to characterize the synthesized zeolites (4A, 5A and Y), zeolite 3A X (commercials) using many techniques, in order to determinate its chemical composition, crystalline structure, morphology and thermal behavior. Finally, the selected zeolites were used as adsorbents in formulations of polyaspartic paints to evaluate the efficiency in the removal of water molecules. According to the results, the zeolite syntheses were effective and could be used in the comparative tests. After that, the zeolites were added as adsorbents in polyaspartic formulations and it was noted that zeolite NaX was the best adsorbent, since it has the properties of hydrophilicity and opening of micropores that allow greater water adsorption in the channels. In the reaction kinetics test, it was observed that all zeolites had a positive impact on the polyaspartic coating, being the zeolite Na-X the best adsorbent, concluding that it is the most suitable for this purpose.