Produção e caracterização química, térmica e mecânica de resinas epóxi a base de óleos vegetais para aplicação em soldagem a arco com eletrodos revestidos

• Ano de defesa: 2015
• Autor(a) principal: Fernando Cabral Lage
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; UFMG
• Palavras-chave em Português: Óleo de soja epoxidado; Fontes renováveis; Eletrodos revestidos; Resina epóxi; Soldagem; Resinas epoxi; Oleo de soja; Eletrodos; Engenharia mecânica
• Link de acesso: http://hdl.handle.net/1843/BUBD-A7LGYL

In view of increasing concern in replacing petroleum derivatives from renewable sources in the production of epoxy resins has been extensively studied the production of various vegetable oils epoxidized using the methodology reported in the literature to the production from peracetic acid generated in situ by heterogeneous catalysis. They were also produced the methyl esters of fatty acids as a way to reduce the viscosity of the resins from renewable sources, enabling their application in the production of lubricants. A new method for epoxidation, more environmentally friendly, has been developed by substituting acetic acid for citric acid produce resins with relative oxirane oxygen conversion of 77%. characterization of thermoplastic resins iodine content was performed oxirane oxygen, viscosity and infrared spectroscopy by Fourier Transform. The epoxidized soybean oils produced with acetic acid present oxygen content of 7% w / w higher than that of commercial resins and RenLamM Barracuda AR-300. The curing of epoxidized oils produced vegegais with citric acid and acetic acid was performed with maleic anhydride, producing thermosetting resins apparent good flexibility and can be subsequently added to the formulation of the commercial resins in order to increase toughness. the characterization of the cured resins was performed by thermal analysis, contact angle of water, infrared and compression testing. The final application of the resins produced as binders in the production of electrodes produced good quality welds, but with thin hard microstructure, based on martensite, bainite and ferrite-carbide. However, the use of commercial epoxy resin RenLam M with the addition of the stabilizer to finish potassium feldspar produced the best results, with great stability of the arc and microstructure with high content of acicular ferrite, keeping a good outlook for future work.