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dc.contributor.advisorVINHAS, Glória Maria-
dc.contributor.advisorSARUBBO, Leonie Asfora-
dc.contributor.authorSOUZA, Thais Cavalcante de-
dc.date.accessioned2025-08-01T12:14:08Z-
dc.date.available2025-08-01T12:14:08Z-
dc.date.issued2025-02-27-
dc.identifier.citationSOUZA, Thaís Cavalcante de. Material híbrido de celulose bacteriana com magnetita: produção, otimização e aplicação. 2025.Tese (Doutorado em Ciências dos Materiais) – Universidade Federal de Pernambuco, Recife, 2025.pt_BR
dc.identifier.urihttps://repositorio.ufpe.br/handle/123456789/64775-
dc.description.abstractsaturação de 50,38 emu/g, um valor 73,7% maior que o apresentado pelas partículas não otimizadas, um menor diâmetro de cristalito, de 6,96 nm, e os materiais de CB produzidos atingiram maiores magnetizações de saturação, entre 29,69 a 36,22 emu/g. Estes materiais foram testados para a aplicação em blindagem contra EMI, e apresentaram resultados que indicam a possibilidade de sua utilização em pastilhas multicamadas, como matriz para a adição de outros dopantes, e para bloquear a poluição secundária, gerada pela reflexão de ondas eletromagnéticas.pt_BR
dc.language.isoporpt_BR
dc.publisherUniversidade Federal de Pernambucopt_BR
dc.rightsopenAccesspt_BR
dc.rights.urihttps://creativecommons.org/licenses/by-nc-nd/4.0/pt_BR
dc.subjectCelulose Bacterianapt_BR
dc.subjectMagnetismopt_BR
dc.subjectMagnetitapt_BR
dc.titleMaterial híbrido de celulose bacteriana com magnetita: produção, otimização e aplicaçãopt_BR
dc.typedoctoralThesispt_BR
dc.contributor.advisor-coCOSTA, Andréa Fernanda de Santana-
dc.contributor.authorLatteshttp://lattes.cnpq.br/0084771728068291pt_BR
dc.publisher.initialsUFPEpt_BR
dc.publisher.countryBrasilpt_BR
dc.degree.leveldoutoradopt_BR
dc.contributor.advisorLatteshttp://lattes.cnpq.br/6404643744960977pt_BR
dc.contributor.advisorLatteshttp://lattes.cnpq.br/4691045388698504pt_BR
dc.publisher.programPrograma de Pos Graduacao em Ciencia de Materiaispt_BR
dc.description.abstractxBacterial cellulose (BC) is a biopolymer obtained through fermentation, possessing unique properties that make it an ideal matrix for the production of advanced hybrid materials, such as magnetic films. The production of magnetic BC biofilms typically involves the incorporation of magnetite nanoparticles through processes like in situ and ex situ coprecipitation. The parameters of each method influence the magnetic characteristics of the material, which can be applied in various fields. Among these applications, electromagnetic interference (EMI) shielding stands out as a growing area due to the increasing use of EMI-based technologies and their impacts on health and the environment. In this study, hybrid bacterial cellulose materials incorporated with magnetite nanoparticles were developed. Initially, different fermentation media were investigated for BC film production, where the culture medium enriched with corn steep liquor showed higher fiber production. Subsequently, methods for the synthesis and incorporation of magnetite nanoparticles into BC biofilms were explored, evaluating both in situ and ex situ coprecipitation methods in intact and processed biofilms. The material obtained via ex situ coprecipitation with processed BC demonstrated satisfactory results, such as high saturation magnetization and better reaction control. This methodology was optimized by adopting a higher stirring speed, altering the reagent ratios, and introducing a purification step for the obtained nanoparticles. As a result, the particles exhibited superparamagnetic behavior, with a saturation magnetization of 50.38 emu/g, 73.7% higher than the non-optimized particles, and a smaller crystallite diameter of 6.96 nm. The produced BC materials achieved higher saturation magnetizations, ranging from 29.69 to 36.22 emu/g. These materials were tested for EMI shielding applications, showing promising results indicating their potential use in multilayer pellets, as matrices for the addition of other dopants, and for blocking secondary pollution generated by electromagnetic wave reflection.pt_BR
dc.contributor.advisor-coLatteshttp://lattes.cnpq.br/1529389745658217pt_BR
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