Navegando por Autor "Quintão, Cristiane Medina Finzi"

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Biodegradable polymers based on natural carotenoids.
(2022) Quintão, Cristiane Medina Finzi; Gualberto, Mariana Simões; Mesquita, Joao Victor; Silva, Ana Cláudia Bernardes; Melo, Tânia Márcia Sacramento; Novack, Kátia Monteiro
Carotenoids such as curcumin and bixin are polyisoprenoids, and are responsible for red, orange or yellow colors. Curcumin is a yellow hydrophobic polyphenol that presents a low molecular weight. Bixin is a natural color extracted from the Annato tree and its color varies from yellow to red due to the presence of the isomer carotenoid trans-bixin. Food and cosmetic industries use them due to their antioxidant properties. The biodegrading properties of polymer blends can be improved by the addition of vegetable oil, organic and inorganic additives or by mixing them with a biodegradable polymer. According to previous studies, polymers produced by a mixture of Moringa polymer (PMO), polyethylene (PE) and commercial biodegradable polymers (PB), composed of PBAT (poly(butylene adipate-co-terephthalate)/PLA (polylactic acid), presented mechanical properties similar to those of PE, except for a higher biodegradation capacity. Vegetable oils can be used as plasticizers for polymer blends and Moringa oil and improved the biodegradation properties in other studies.
Biodegradation of Moringa oleifera’s polymer blends.
(2019) Quintão, Cristiane Medina Finzi; Novack, Kátia Monteiro; Silva, Ana Cláudia Bernardes; Silva, Thais D.; Moreira, Lucas Emiliano de Souza; Braga, Luiza Eduarda Moraes
Vegetable oils are used as a base for the synthesis of polymers and monomers with structures similar to that of petroleum, as plasticizers for conventional polymers and biodegrading additives. The Moringa oleifera oil was extracted from seeds and polymerized after being submitted to 16 h of microwave irradiation without catalysers. This polymer was characterized and the efficiency of the oil polymerization was verified by the reduction of double bonds and the increase of molecular weight up to 50,000 g mol−1. Films produced by a mixture of low-density polyethylene (LDPE) with poly(butylene adipate-co-terephthalate)/poly(lactic acid) (PBAT/PLA) present low tensile resistance and low biodegradation behaviour. In order to improve those properties, the Moringa polymer (PMO) was mixed with LDPE and PBAT/PLA in specific mass concentrations. The films produced with this mixture were characterized and submitted to biodegradation analysis. The PMO behaves as a compatibilizer by improving thermal properties, reducing the crystalline phase and improving the biodegradation behaviour. The biodegradation improved up to five times in comparison to conventional polymers and it restores the mechanical properties.
Cenários prospectivos para a produção de derivados de Moringa oleífera : uma abordagem sistêmica.
(2022) Freire, Estêvão; Novack, Kátia Monteiro; Melo, Tânia Márcia Sacramento; Quintão, Cristiane Medina Finzi; Gualberto, Mariana Simões
Obtaining bioproducts from renewable sources from agroforestry and agro-industrial residues has been boosted in recent years due to limited availability of fossil sources and the global environmental concern. Among the raw materials, Moringa oleifera stands out, a tree native to India and present in several countries, including Brazil. From different parts of the tree, high value-added products can be obtained, such as drugs, biopesticides and bioplastics. The present work consisted of an analysis of patent documents, articles and sector reports, related to the production of bioplastics, more specifically polyurethane foams. Based on the data collected, a sectoral analysis of strengths, weaknesses, opportunities and threats (SWOT) was carried out related to the potential for obtaining bioplastics from moringa derivatives, which was complemented with PESTEL analysis (involving political, economic, social, environmental and legislation aspects). The results showed that despite the low production of patents in the area of bioplastics from Moringa derivatives, there is an opportunity in Brazil for the production of drugs and food, considering the great versatility of Moringa cultivation and of obtaining products, combined with policies that boost the bioeconomy in Brazil.
Estudo de compósitos cimentícios com adição de fibra natural da Moringa oleifera.
(2022) Ishihara, Marina Keiko; Novack, Kátia Monteiro; Silva, Guilherme Jorge Brigolini; Quintão, Cristiane Medina Finzi; Novack, Kátia Monteiro; Silva, Guilherme Jorge Brigolini; Quintão, Cristiane Medina Finzi; Pedroti, Leonardo Gonçalves; Mendes, Júlia Castro
Como uma alternativa atrativa aos materiais de engenharia tradicionais, o estudo de materiais compósitos com fibras naturais vem avançando cada vez mais. Isto se deve ao fato de que as fibras se apresentam como uma solução de baixo custo, boa disponibilidade e baixo impacto ambiental. Seguindo a tendência de se obter materiais mais baratos e sustentáveis, este projeto aborda o estudo de compósito com matriz cimentícia de Cimento Portland de Alta Resistência Inicial (CP-V ARI) e reforço de fibra da Moringa oleifera. Ensaios com a casca in natura foram realizados para melhor conhecimento do material estudado. Quimicamente, foi determinado o teor de cinzas, teor de lignina e o teor de extrativos totais. Fisicamente, foi determinado o teor de absorção, a umidade natural e a massa específica da fibra. A topografia e um mapa de elementos da fibra foram observados através do Microscópio Eletrônico de Varredura (MEV) e da Espectroscopia por Energia Dispersiva (EDS). Depois, a casca da semente da moringa foi misturada a dois traços distintos de argamassa, nos teores de 0,0%, 2,5%, 5,0%, 7,5% e 10% em relação a massa de cimento. Foram confeccionados corpos de prova cilíndricos, submetidos ao ensaio de Velocidade de Pulso Ultrassônico e Resistência à Compressão, aos 7 e 28 dias. Estes corpos de prova rompidos foram analisados em MEV e EDS, para análise da interface fibra/matriz e compostos formados devido à adição da fibra. Os resultados mostram que a presença da fibra não permitiu a formação de compostos hidratados de cimento suficientes, resultando em uma matriz porosa, com presença de fissuras e baixa resistência mecânica. Há grande presença de portlandita na interface da fibra e da matriz de cimento, e consequente meio alcalino, o que ataca a fibra natural. Com isto, a adição de fibra neste tipo de compósito impossibilita a sua utilização onde há necessidade de resistência mecânica.
Estudo de misturas poliméricas formadas por PEBD e plásticos biodegradáveis com o óleo e o polímero de moringa oleífera.
(2017) Quintão, Cristiane Medina Finzi; Novack, Kátia Monteiro; Silva, Ana Cláudia Bernardes; Novack, Kátia Monteiro; Santos, Viviane Martins Rebello dos; Freire, Estêvão
O desenvolvimento da tecnologia dos polímeros permitiu a produção de produtos plásticos resistentes, duráveis e com menor custo de produção quando comparado aos metais. Os plásticos estão presentes na sociedade em uma diversidade infinita de produtos. A vantagem de produção de um material durável esbarra na dificuldade de descarte do produto velho para a compra de um novo, situação não desejável em uma sociedade de consumo. Os estudos relacionados à adição de óleos vegetais em polímeros comerciais (poliestireno, poliestireno e polipropileno) indicam que valores entre 2% a 5% em massa melhoram a capacidade biodegradante do material sem impactos significativos nas propriedades mecânicas. A Moringa oleifera lam é uma árvore do nordeste da Índia que se adapta em quase todos os tipos de solo. O óleo extraído das sementes é estudado na produção de biocombustíveis e bio-lubrificantes e em menor proporção como aditivos para polímeros comerciais. Nesse estudo tratamos a utilização de uma porcentagem ideal em massa de óleo de moringa (MO) ou de polímero do óleo (PMO) que permita a interação entre as estruturas dos polímeros das sacolas plásticas (PB) e o polietileno de baixa densidade de sacos transparentes (PE). Os filmes formados pelo MO ou pelo PMO com a mistura PEPB foram caracterizados e submetidos a testes de biodegradação. As análises térmicas indicaram que o aumento da proporção de MO ou PMO aumenta a estabilidade térmica da mistura. Os testes de tração indicaram que o filme MO-PE-PB (sem pigmentação) apresentou comportamento similar ao do PEPB em relação à tensão de ruptura e ao alongamento, embora tenha reduzindo significativamente a rigidez em relação ao PEPB. No caso do PMO-PE-PB ocorreu o aumento da resistência à tração, mas, a exemplo do MO-PE-PB, o filme apresentou redução da rigidez. As amostras pigmentadas apresentaram perdas consideráveis nas propriedades mecânicas. A capacidade de biodegradação das amostras PMO-PE-PB foi superior ao verificado nas amostras MO-PE-PB. A pigmentação não favoreceu a degradação dos filmes. As micrografias, o teste de molhabilidade e os testes de biodegradação indicaram a presença de poros nos filmes poliméricos, os quais influenciaram na celeridade do processo de biodegradação. O presente trabalho propõe a obtenção de filmes poliméricos biodegradáveis compostos pela mistura de polímeros biodegradáveis (PB) com polietileno de baixa densidade (PEBD), aqui chamados simplesmente de PE e derivados do óleo da semente de Moringa oleifera.
Identification of biodegradable and oxo-biodegradable plastic bags samples composition.
(2016) Quintão, Cristiane Medina Finzi; Novack, Kátia Monteiro; Silva, Ana Cláudia Bernardes
Plastic films used to make market bags are based on polymers such as polyethylene, polystyrene and polypropylene. These materials require a long time to degrade in the environment. Alternative technologies have been developed to reduce the degradation time and the impact on the environment caused by the conventional polymer materials, using pro-degrading additives or by the development of biodegradable polymers. In Brazil, some city’s laws require the use of biodegradable material in the production of market bags, but the absence of specific surveillance policies makes their chemical composition unknown. The plastic bags didn’t show the expected environmental behavior by the manufactures, so it is important to understand the reasons why they are not biodegradable in Brazilian landfills. In this paper, 7 samples that were obtained from a trading company and commercial market of Belo Horizonte were analyzed. The samples were characterized by biodegradable analysis, XRF, FTIR, SEM and TGA/DTA, which allowed the identification and evaluation of the thermal behavior of the material in an inert and oxidizing atmosphere. The results showed that plastic bags were composed by a mixture of PLA and PBAT, with possible presence of TPS and titanium and calcium fillers. All samples presented low biodegradability in compostable environment.
Influence of Moringa oleifera derivates in blends of PBAT/PLA with LDPE.
(2018) Quintão, Cristiane Medina Finzi; Novack, Kátia Monteiro; Silva, Ana Cláudia Bernardes; Silva, Thais Dhayane; Moreira, Lucas Emiliano de Souza; Braga, Luiza Eduarda Moraes
There are few studies about Moringa oleifera derivates in polymer developments where vegetable oil was used as a plasticizer and a biodegrading agent. The polymerization of moringa oil (MO) was carried out assisted by microwaves without catalysts presence. There aren’t studies about the polymerization of MO using microwaves technology. Moringa’s oil and its polymer (PMO) were used as a biodegrading agent for mixtures of low density polyethylene (LDPE) with poly(butylene adipate-co-terephthalate)/poly(lactic acid) (PBAT/PLA). The mixtures producted films that were characterized and submitted to biodegradation analysis in order to discuss the influence of moringa components. Results showed that both moringa components improved thermal properties and reduced the crystalline phase of the mixture. The addition of PMO had improved the biodegradation capacity up to five times while MO had improved it up to three times. The results showed the greatest influence of moringa components on biodegradation of mixtures with cited polymers.
Modeling and optimization of hybrid leachate treatment processes and scale-up of the process : review.
(2021) Vaz, Carlos Alberto dos Santos; Samanamud, Gisella Lamas; Silva, Ricardo Soares da; França, Alexandre Bôscaro; Quintão, Cristiane Medina Finzi; Urzedo, Ana Paula; Silva, Messias Borges; Bosch Neto, Juan Canellas; Amaral, Mateus de Souza; Loures, Carla Cristina Almeida; Naves, Luzia Lima Rezende; Naves, Fabiano Luiz
Optimized models of landfill leachate processes that could lead to the production of fuel oils from the pyrolysis of plastics and cultivation of microalgae, can be high-efficient and sustainable activities. Studies using advanced oxidation processes in combination with biological processes showed to be efficient in treating leachate. The complexity of this type of waste, as well as the continuous modification of its properties due to local seasonality, prevent kinetic and thermodynamic studies to predict the steady state at the final disposal. Environmental management system using Lean Six sigma accompanied with process modeling and optimization tools, whether statistical or computational, generate reliable models. These models can reproduce reductions on contaminants by confirming the initial conditions of each leachate enabling the scale-up of the process. This Review provides data survey, types of treatment and models linked to optimization tools in wastewater decontamination processes from municipal solid waste (MSW). This review includes the synthesis and proposal for treatment and man- agement from of the classification of the garbage until the generation of leachate, aiming to contributing to future researches in the leachate treatment.
Modeling and optimization of the pyrolysis oil production process from polypropylene for the production of aviation kerosene.
(2022) Santos, Heraclito Alexandre dos; Santos, Igor José Boggione; Quintão, Cristiane Medina Finzi; Knupp, Vagner Fernandes; Lofrano, Renata Carolina Zanetti; Oliveira, Eliane Cristina de; Samanamud, Gisella Lamas; Amaral, Mateus de Souza; França, Alexandre Bôscaro; Pereira, Mariana Arruda; Silva, Matheus Teixeira Araújo; Loures, Carla Cristina Almeida; Carneiro, Mozart dos Santos; Ponciano, Jéssica Amaral Pereira; Naves, Luzia Lima Rezende; Naves, Fabiano Luiz
One of the greatest challenges in the world is in the fnal disposal of plastics in order to reduce the efect of its polluting potential. Thus, the application of pyrolysis processes in generating products of interest such as fuel oils can be part of the solution. In addition to reducing greenhouse gas emissions to the atmosphere, oil can enter the supply chain after the cracking process in petrochemical industries. In this context, this work used statistical modeling of the response surface linked to the normal boundary intersection algorithm, aiming at a higher yield of oil production and major selectivity of recycled polypropylene pyrolysis. From the analysis of the mechanisms proposed in the literature with the modeling and optimization in this work, it was possible, from a kaolin mass of 9.12 g and a heating ramp of 19.37 °C/min, to obtain higher percentages of aviation kerosene as well as a satisfactory performance.
Moringa oleifera oil and polymer in mixtures with commercial polymers – comparing study.
(2018) Quintão, Cristiane Medina Finzi; Silva, Ana Cláudia Bernardes; Melo, Tânia Márcia Sacramento; Moreira, Lucas Emiliano de Souza; Silva, Thais D.; Novack, Kátia Monteiro
Composites may be obtained by the mixture of two materials, which one of them is a polymer, with the objective of produced a material with a specific characteristics. Vegetable oils (VO) are mixture with conventional polymer to improve biodegradation capacity without loss mechanical properties. VOs polymers are an alternative to conventional polymers on composites. Previous studies showed that the mixture of Moringa oleifera polymer (PMO) with polyethylene (PE) and biodegradable polymer (PB) producing a composite with high biodegrading capacity maintaining mechanical properties. M. oleifera oil (MO) was obtained from extraction of seeds in and presents higher concentration of instauration fatty acids as oleic acid (71%) which has high stability and favors the polymerization process. The polymerization assisted by microwaves technology can be used in organic synthesis as a function of the process efficiency and the increase in the selective heating rate. The polymerization of MO assisted by microwaves produced a polymer (PMO) with molecular weight higher than 50,000 g.mol-1.This manuscript shows comparing results for biodegradation behavior and mechanical properties of mixtures by MO or PMO with low density polyethylene and the commercial biopolymer composed by poly (butylene adipate-co-terephthalate) (PBAT) with poly(lactic acid) (PLA). It was verified that MO presented a plasticizer behavior on mixture LDPE/PBAT/PLA (PM) and PMO presented a compatibilizer behavior with PM. It was also verified that mixtures with PMO presented better biodegradation and mechanical properties than those composed by MO.
Moringa oleifera oil influence on biodegradation behaviour of polymers.
(2018) Quintão, Cristiane Medina Finzi; Melo, Tânia Márcia Sacramento; Silva, Ana Cláudia Bernardes; Novack, Kátia Monteiro
Vegetable oils (VOs) can be used as plasticizers or as biodegrading additives for commercial polymers. According to the literature, the use of concentrations higher than 5% of oils added to polymers or their mixtures indicated loss of mechanical properties on the final product. However, VOs can be used as a compatibilizer for the mixture of synthetic polymers with biopolymers (PM) under concentrations higher than 5%. Moringa oleifera oil (MO) was used as a compatibilizer to PM mixtures using oil concentrations higher than 5%, 10% and 15% in mass. PMs were analysed at first based on mechanical properties which indicated a better concentration at 15% of MO. This article presents a study of MO influence on biodegradation behaviour of PM, which was composed of low-density polyethylene obtained from food bags and biopolymers (PB) obtained in market plastic bags. PM doped with different concentrations of MO was submitted to studies of mechanical, chemical, morphological and thermal properties and their biodegradation behaviour was evaluated. The concentration of 15% of MO increased the thermal resistance of PM, improved the biodegradation behaviour according to controlled and free tests and reduced its stiffness without a loss of important mechanical properties. The results of this work showed that MO influenced positively the biodegradation of the PM mixture by improving 30% of the degrading speed.
Synthesis and characterization of polyurethane foam based on vegetable oil.
(2022) Gualberto, Mariana Simões; Quintão, Cristiane Medina Finzi; Rodrigues, Kethory Shirleny Barros; Romão, Wanderson; Novack, Kátia Monteiro; Baston, Eduardo Prado
This research shows the production and characterization of the polyurethane foam produced from moringa oil with low energy expenditure. Vegetable oil, polyol and the foam were characterized by hydroxyl, acid and Iodine index, Fourier Transform Infrared Spectroscopy (FTIR), 1 H RMH spectra, Thermo gravimetric analysis (TG), Scanning Electrical Microscopy (SEM), X-Ray Diffractogram (XRD) and Mass Spectroscopy. The physical-chemical results showed the modified oil potential for the polyurethane formation reaction due to the hydroxyls index of 257.52 mg KOH g-1 and acidity of 2.38 mg KOH g-1 . FTIR spectra showed the hydroxylation reactions and urethane groups formation in the oil by bands wich referring to hydroxyl groups and their NH groups superposition. Foam TG showed a degradation profile between 281 °C and 750 °C, losing half of its mass in temperatures higher than 400 °C. Micrographies showed that foam is composed by opened and closed cells, characteristic of semi-flexibility of the foam.