Caracterização e aplicação de fibras obtidas por eletrofiação de PLA/PBAT com grafite incorporado

• Ano de defesa: 2018
• Autor(a) principal: Pozza Junior, Mario Cezar
• Orientador(a): Dragunski, Josiane Caetano
• Banca de defesa: Dragunski, Josiane Caetano , Dragunski, Douglas Cardoso , Medeiros, Roberta Antigo
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Estadual do Oeste do Paraná; Toledo
• Programa de Pós-Graduação: Programa de Pós-Graduação em Ciências Ambientais
• Departamento: Centro de Engenharias e Ciências Exatas
• País: Brasil
• Palavras-chave em Português: Eletrofiação; Meio ambiente; Pesticidas; Sensores; Voltametria
• Palavras-chave em Inglês: Electrospinning; Environment; Pesticides; Sensors; Voltammetry
• Área do conhecimento CNPq: OUTROS
• Link de acesso: http://tede.unioeste.br/handle/tede/3765

The need for new tools to detect pollutants and of importance in the subject, electrochemical sensors are shown as a great alternative, considering its low cost, good limits of detection, and speed of analysis. An electro-spinning technique is a small fiber production technique where many possibilities for a sensor construction are offered, mainly using biodegradable polymers. This work has the objective of incorporating polymeric fibers with graphite optimized by an electrochemical technique, as well as an electrochemical sensor capable of obtaining a detection limit for the 2,4,6-trichlorophenol compound. A total of 35 experiments were carried out, using five different electrophilic techniques (needle distance to the collector, flow, tension, % of polymers, and % of graphite), as fibers as morphologically characterized using optical microscopy, SEM and a test of Wettability. For physical e structural analyzes, DSC, TGA and FTIR analyzes were performed, where it was sought to know if the incorporation of graphite into the polymer is capable of altering its structure. Then, for a sensor construction, a membrane obtained by electrospinning was then subjected to a heat treatment of 500°C for 3 hours, the powder obtained was mixed with the Nujol® wetting agent, thereby forming a uniform paste which was inserted into the End of a hypodermic plastic syringe with a silver wire for electrical contact, being manually pressed. The electrode was subjected to a characterization and an evaluation where a limit of detection was established for compound 2,4,6-TCP, in addition to a test with real samples collected in water treatment station supply. The minimum diameter obtained in the fibers was 1.49μm, using where the stress and voltage flows interacted, showing the effect of the second most significant order among all. As it analyzes morphologically revealed that a graphite incorporation has given the polymer membrane new characteristics to the surface, while as thermal analyzes show what is graphite changing a structure of the fibers when incorporated as its own. The only oxidation pic viewed with the Cyclic Voltammetry analysis characterizated the sensor containing a irreversible behavior face to 2,4,6-TCP. Based on the Square Wave Voltammetry analyzes, was obtained a detection limit for the 2,4,6-TCP of 1x10-7 mol.L-1 and showed a detection of the concentration test of 6x10-7 mol.L-1, with recovery rates of water samples between 80 and 93%, both in accordance with current Brazilian legislation.