Espuma de poliuretano de base biológica customizada com recobrimentos de copolímeros híbridos nanoestruturados para tratamento de múltiplos contaminantes aquosos

• Ano de defesa: 2024
• Autor(a) principal: Philipe Augusto Pocidonio Silva
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; Brasil; ENG - DEPARTAMENTO DE ENGENHARIA METALÚRGICA; Programa de Pós-Graduação em Engenharia Metalúrgica, Materiais e de Minas; UFMG
• Palavras-chave em Português: Poliuretano; Nanocompósito; Dióxido de titânio; Separação de fase; Automontagem; Copolímeros em bloco; Águas; Materiais; Ciência dos materiais; Água - Purificação; Nanocompósitos (Materiais); Copolímeros
• Link de acesso: http://hdl.handle.net/1843/74824; https://orcid.org/0000-0003-0235-9319

Projections show that, by 2025, half of the world's population will live in areas with water scarcity. This scenario of the absence of disponibility water is also due to anthropogenic activities and expensive drinking water-obtaining processes. Therefore, there is a need to develop new multifunctional and increasingly effective materials. In this project, a hybrid system was produced consisting of polyurethane foam, mesoporous cellulose/halloysite nanosystems covered with diblock copolymers of poly(styrene-b-ethylene-ran-butylene-b-styrene) (SEBS) and poly(styrene-b -4-vinylpyridine) (PS-b-P4VP) containing (TiO2) titania. From the mimicry of hierarchical porous structures using synthesis techniques via sol-gel, hydrothermal, in situ polymerization with chemical expansion, and phase inversion processes generating self-assembling structures, the necessary functionality for a dye decontaminating system was obtained. methylene blue, adsorption of heavy metals such as Manganese, Nickel and Cobalt, and adsorption of proteins (myoglobin) from contaminated water. The study of the new material revealed that the cellulose/halloysite mesoporous nanocomposite in different proportions (0, 5 and 10)m/m% in the foam was responsible for a 5.5 times increase in the manganese (Mn2+) adsorption capacity after 30 minutes of contact with a solution containing this ion at pH=6.5 for the foam containing 5% nanocomposite and 11.4 times for the foam containing 10% of nanocomposite, compared to the pure polyurethane sample. Adsorption values also increased for nickel Ni2+ and Cobalt Co2+. Copolymer membranes containing mesopores and titania nanoparticles (0; 0.5; 1.0) m/m% were obtained and increased myoglobin adsorption by at least 50% compared to foam containing 10% nanocomposite (Ce/Ha). Furthermore, the TiO2 nanoparticle added for the first time by the non-solvent solution in the phase inversion process, made it possible to increase the photocatalytic activity and degradation of methylene blue dye in the tested compositions by 10%. The system developed in this work was modulated for the first time and demonstrates an unique potential in acting as a multiple decontaminant in aqueous media.