PEDRO MARCIO MUNHOZ
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Artigo IPEN-doc 30572 Development of an epoxy/carbon fiber composite for radiation attenuation with a dispersion of micro particles of bismuth trioxide (Bi2O3)2024 - MUNHOZ, PEDRO M.; NASCIMENTO, FERNANDO C.; RODRIGUES JUNIOR, ORLANDO; POTIENS, MARIA da P.A.; CALVO, WILSON A.P.Artigo IPEN-doc 29850 Development of an acrylic emulsion paint added with cellulosic dispersion treated with an electron beam accelerator2023 - NASCIMENTO, F.C.; MUNHOZ, P.M.; NASCIMENTO, L.F.N.; CALVO, W.A.P.Paint is a prevalent type of surface of coating well known to most people. It is an easy-to-apply product, with excellent physical and chemical resistance and a wide range of applications. The function of a paint is to protect and beautify amongst other properties. Paints are formed using five components: resin, pigments, fillers, solvents and additives. This work deals with a specific type of paint, composed of a water-based acrylic emulsion, whose film formation is by coalescence and used to coat walls and other surfaces. The aim of this innovative research was to evaluate the effect of the addition of cellulosic dispersion of waste paper tissues treated by electron beam irradiation to an acrylic emulsion-based paint. The methodology used was a case study carried out at the Nuclear and Energy Research Institute that consisted of adding aqueous dispersions of cellulosic wipes with mass concentrations varying from 0.1% to 10% in deionized water, and treated by electron beam processing with absorbed doses from 5 kGy to 50 kGy. The results obtained followed the parameters of the Abrafati Sectorial Quality Program. The main sample parameters analyzed were specific density, which reached an average of 1.35 g/cm3 ; and covering power, whose value of 93.55% was above the specified limit (minimum of 90%). Among other results obtained, improvements in appearance, applicability and functionality were significant. It was concluded that this research constitutes an incremental improvement to the acrylic emulsion paints segment, and environmental sustainability, through the reuse of cellulosic tissue residues.Resumo IPEN-doc 29549 Electron beam processing to improve biodegradable polymers and for industrial wastewater treatment and recycling2022 - CALVO, W.A.P.; MUNHOZ, P.M.; SOMESSARI, S.L.; DUARTE, C.L.; SPRENGER, F.E.; FEHER, A.; LAINETTI, F.F.; GASPAR, R.R.; NASCIMENTO, F.C.; SILVA, L.G.A.; HARADA, J.; BRAGA, A.; RODRIGUES, M.; SAMPA, M.H.O.Radiation technology has been used to control environmental pollution. The aim of these studies was to apply the electron beam radiation technology for controlling plastic pollution and environmental protection.Artigo IPEN-doc 29182 Simulation of radiation attenuation in polymer matrix composite with epoxy resin, reinforced with carbon fiber and dispersion of bismuth oxide (Bi2O3) nanoparticles2022 - MUNHOZ, PEDRO M.; NASCIMENTO, FERNANDO C.; SILVA, LEONARDO G.A.; GARY, BRUNO C.; CALVO, WILSON A.P.The aim of this study was to simulate gamma radiation attenuation using a polymer matrix composite of an epoxy (DGEBA) resin that was reinforced with carbon fiber cloth fabric and then dispersed with bismuth (III) oxide (Bi2O3) nanoparticles. The quantitative methodology was used for this simulation with the software Topas MC (version 3.7). The mass ratios of the bismuth (III) oxide nanoparticles in the composite were approximately 0.163, 0.244, 0.325 and 0.407. The photon energy in the simulation was 100 keV, typical X-ray energy in Medical Imaging (Diagnostic Radiography). The mass ratio of 0.407 and the polymer matrix composite at a thickness of 2.29 mm provided 89.03% attenuation of the photon energy. However, for the lead plate, a thickness of 0.34 mm was necessary for similar attenuation. Nonetheless, the fabrication process of a composite plate is easier than that of a lead plate. In conclusion, a composite of an epoxy polymer matrix, with bismuth (III) oxide dispersion, reinforced with carbon fiber, is an excellent option as compared to a lead plate. The composite plate can attenuate photon energy and does not present an acute or chronic danger to the environment or to health. Also, it is non-carcinogenic, and does not cause reproductive toxicity, both clear advantages over lead. Finally, it should be noted that other applications of the composite would be production of an X-ray shield and aerospace industries, among others.Artigo IPEN-doc 29181 Evaluation of polyester/glass fiber waterproof composite subjected to temperature and acid environment2022 - GARY, B.C.; MARINUCCI, G.; MUNHOZ, P.M.; SILVA, L.G.A.Polymer composites have a wide range of chemical applications, with strong performance in the paper and cellulose and sugar-alcohol industry due to the chemical resistance such materials offer because of the presence of the polymer matrix. The literature shows that vinyl ester resins offer chemical resistance for these applications, however at a higher price than commercial resins, such as unsaturated polyesters. The aim of this research was to evaluate the chemical resistance of glass fiber reinforced waterproof polyester resin composites (GFPO). Composite was manufactured by hand lay-up and the waterproof polyester specimens were kept immersed in a buffer solution with pH 3 at 70 °C for 150 days. To evaluate the behavior of waterproof polyester composites, flexural tests were performed and compared with properties of the vinyl ester composites. After the chemical resistance test, the GFPO composite presented a Young’s modulus of 6 GPa with a maximum flexural of 100.6 N. In conclusion, a waterproof polyester resin composite can be a good option for applications in corrosive environments where a vinyl ester resin composite would be applied.Artigo IPEN-doc 28339 Influence of electron beam irradiation on the mechanical properties of pbat/pla polymeric blend2021 - MUNHOZ, PEDRO M.; NASCIMENTO, FERNANDO C.; SILVA, LEONARDO G. de A. e; HARADA, JULIO; CALVO, WILSON A.P.The aim of this research was to evaluate the changes in the mechanical properties of poly(butylene adipate co-terephthalate)/poly(lactic acid) (PBAT/PLA) polymeric blend after the radiation process at different radiation doses. The irradiation was performed in an electron beam accelerator, with 1.5 MeV of energy and 25 mA electric current. The samples were irradiated with doses of 5, 10, 15, 25, 50, 65 and 80 kGy. Both irradiated and non-irradiated samples were characterized by Izod pendulum impact resistance and tensile strength at rupture. The results showed an increase of 44% in relation to Izod impact resistance at a dose of 65 kGy. However, the module of elasticity decreased 56% and tensile strength at rupture decreased 55% at the same radiation dose. In relation to elongation, significant alterations caused by electron beam irradiation was not observed. Therefore, it can be concluded that irradiated blends could be used to make environmentally friendly products, which could absorb impact energy.Dissertação IPEN-doc 27501 Caracterização da blenda de PBAT/PLA poli (butileno adipato cotereftalato)/poli (ácido lático) irradiada por feixe de elétrons2020 - MUNHOZ, PEDRO M.O objetivo desta pesquisa foi caracterizar da blenda polimérica de Poli(adipato de butileno co-tereftalato)/Poli (ácido lático) (PBAT/PLA), após processamento de irradiação com feixe de elétrons em diferentes doses. As amostras foram irradiadas com doses absorvidas de 5, 10, 15, 25, 50, 65 e 80 kGy, após irradiação, foram submetidas aos experimentos de ensaios de tração, impacto, dureza, termogravimetria, calorimetria exploratória diferencial, difração de raios X (DRX) e suscetibilidade microbiana. Os resultados mostraram um incremento de 44% em relação à resistência ao impacto na dose absorvida de 65 kGy, porém o módulo de elasticidade diminuiu 56%, e a tensão de ruptura diminuiu 55% nesta mesma dose. Em relação ao alongamento, não foram observadas alterações significativas causadas pela radiação o mesmo ocorrendo com: a dureza, o grau de cristalinidade, analisada por meio do ensaio de DRX, a suscetibilidade microbiana e a temperatura de transição vítrea. Para a termogravimetria - TG foi observado um incremento de 17,4% na dose absorvida de 65 kGy, em relação ao calor de mudança cristalina do PLA, observou-se um acréscimo de 13,1% na dose de 80 kGy, entretanto, para esta mesma dose, verificou-se uma redução de: 2,4% na temperatura de fusão e de 12,1% no calor de fusão da blenda de PBAT/PLA. Para o grau de cristalinidade, analisado por meio do DSC, pode-se observar um decréscimo de 12,1%. Concluindo, essa mistura irradiada, conforme prevista pode ser usada para produzir produtos ambientalmente amigáveis os quais podem absorver energia de impacto e obter mais estabilidade térmica quando a blenda polimérica de PBAT/PLA é irradiada com a dose de 65 kGy.Artigo IPEN-doc 26286 Poly (butylene adipate co-terephthalate)/poly (lactic acid) (PBAT/PLA) blend characterization processed by electron beam2019 - MUNHOZ, PEDRO M.; SILVA, LEONARDO G. de A. e; HARADA, JULIO; NASCIMENTO, FERNANDO C.; CALVO, WILSON A.P.The aim of this research was to check the changes in the mechanical and thermal properties of poly(butylene adipate co-terephthalate)/poly(lactic acid) (PBAT/PLA) polymeric blend, which commercial name is Ecovio®, after radiation processing in different absorbed doses. PBAT and PLA are biodegradable polymers and the Ecovio® polymeric blend consists of at least 80% of polymers from renewable resources. The irradiation was performed in a Radiation Dynamics Inc. electron beam accelerator, with 1.5 MeV of energy and electric current of 25 mA. Samples were prepared for micrograph, mechanical and thermal analyses. These samples were irradiated with absorbed doses of 5 kGy, 10 kGy, 15 kGy, 25 kGy and 50 kGy. The samples, after irradiation, were submitted to experiments of ultimate strength, tensile strength, ultimate elongation, differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). The results showed a good interaction between the components of the polymeric blends and the radiation effect on polymeric blend promoted changes in PBAT and PLA polymers, increasing tenacity of these biopolymers and consequently facilitating yarn formation in processing. In conclusion, these irradiated blends could be used to make environmental friendly products.