Navegando por Palavras-chave "Tintas"

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    Avaliação da disponibilidade de chumbo em ambientes escolares no ensino público da cidade de Diadema
    (Universidade Federal de São Paulo, 2013-12-16) Muniz, Luis Robson [UNIFESP]; Assunção, Nilson Antonio de [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    This work, we have focused on the issue of lead poisoning, in the process of neurocognition of schoolchildren, and in this respect , is widely cited in the literature that lead contamination has deleterious effects on the brain system (Bellinger, 2008), and behavior (Liu, 2011) in both children and adults . The mechanisms that explain this effect are still not very clear, but there is evidence that lead in their ionic speciation as Pb2+, present a certain biomimicry chemical on the role of Ca2+ metabolism nerve that occurs in the system hypothalamus-pituitary brain (Neal, 2011). The attention regarding lead contamination should fall primarily on substrates, in which it is present ionized as it is more soluble bioactive and, thus, the ceramic matrix deserve special attention in relation to the metallic or polymeric. There are cases of contamination by the ceramic material (Galvez, 2003), however, it is noted that a majority of the contamination plumbic ceramic suspensions of their oxides and salts, or the paints used for coating in construction industry (Brown, 2005). In this study we determined the levels of lead, using a portable X-ray fluorescence to give semi-quantitative values of the contaminant in situ, and, in order to investigate a possible correlation between the levels of lead present in the school environment with the academic performance of students, used as comparator Development Index of Basic Education - IDEB, the schools that were the target of this research. Few studies that address the issue of lead poisoning, considering the school environment as a possible field of cumulative absorption of this contaminant, which is why our research will seek this contribution.
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    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 Paulo
    The 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.
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    Tintas arquitetônicas e automotivas: um estudo detalhado sobre a sua evolução
    (Universidade Federal de São Paulo, 2022-12-06) Paes, Laíza Felisbino [UNIFESP]; Zanotti, Nadine Mazzocatto [UNIFESP]; Falleiro, Rafael Mauricio Matricarde [UNIFESP]; http://lattes.cnpq.br/7264259801951867; http://lattes.cnpq.br/7422732659370148; http://lattes.cnpq.br/2886562008379466
    As tintas são grandes aliadas da humanidade desde a antiguidade, sendo utilizadas para decorar e também para proteger. Ao longo dos anos esse material teve um grande avanço tecnológico nas formulações e nas aplicações, além do aprimoramento de diversas técnicas de pintura. Ao longo do trabalho discutiu-se sobre a história da tinta, da pintura rupestre até a sua complexidade nos dias atuais, além dos diferentes materiais e sua evolução ao longo do tempo, com lançamento de produtos cada vez mais inovadores, sendo possível encontrar produtos que tenham funções técnicas especiais que melhoram ainda mais seu desempenho. Também foram estudados os impactos, no ambiente e na vida humana, causados por cada tipo de tinta, entendendo os fatores que afetam e de que maneira está sendo solucionado. A partir do estudo aprofundado dos resultados obtidos de trabalhos encontrados nas plataformas de pesquisa compreendeu-se o quanto esse tema está sendo discutido e como são influenciadas com as novas ideias e soluções da atualidade, abrangendo o crescimento de interesse para novas aplicações e inovações, como a diminuição de COV (compostos orgânicos voláteis) e adaptação para tintas em pó. Assim, o mapeamento dos periódicos foi de grande relevância para entender como as pesquisas por tintas arquitetônicas e automotivas vêm crescendo ao longo dos anos, com 4 vezes mais artigos publicados em 2021 comparado à 2002, além de ter levantado uma visão sobre o impacto ambiental, a saúde humana e a demanda do mercado brasileiro que vai auxiliar nas futuras tomadas de decisão.