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Master's Dissertation
DOI
https://doi.org/10.11606/D.3.2014.tde-30122014-113017
Document
Author
Full name
Nikolas Sinji Harada
E-mail
Institute/School/College
Knowledge Area
Date of Defense
Published
São Paulo, 2014
Supervisor
Committee
Wang, Shu Hui (President)
Bartoli, Julio Roberto
Higa, Olga Zazuco
Title in Portuguese
Desenvolvimento de membranas compósitas de poliuretano pelo processo de eletrofiação.
Keywords in Portuguese
Biomateriais
Eletrofiação
Óxido de zinco
Poliuretano
Prata
Abstract in Portuguese
O presente trabalho tem por objetivo o desenvolvimento de um novo material nanocompósito com propriedades biocidas, alta porosidade e alta permeabilidade ao ar, possibilitando sua aplicação na área biomédica. Neste trabalho, foram desenvolvidas membranas compósitas de poliuretano termoplástico (TPU) contendo prata (Ag) e óxido de zinco (ZnO), a partir da evaporação de soluções durante o processo de eletrofiação. Mediu-se as propriedades de viscosidade e de condutividade elétrica das soluções preparadas para eletrofiação. Avaliou-se a modificação da morfologia do material pelo uso de vários solventes em diferentes concentrações. Uma morfologia mais uniforme das membranas contendo fibras eletrofiadas foi obtida com o sistema de solventes tetra-hidrofurano (THF) e dimetilformamida (DMF), na proporção de 50:50. A avaliação da morfologia e da distribuição da fase dispersa inorgânica nas membranas foi efetuada utilizando-se microscopia ótica (MO) e microscopia eletrônica de varredura (MEV), e a formação de fibras com diâmetros na faixa de 250 a 800 nanômetros foi observada. As fases dispersas apresentaram-se distribuídas na membrana, sem a presença de regiões de aglomeração. A presença de prata ou de óxido de zinco nas membranas eletrofiadas foi confirmada através da espectroscopia de energia dispersiva de raios- X (EDS) e por difratometria de raios-X. As propriedades bactericidas das membranas compósitas de TPU/ZnO e TPU/Ag foram avaliadas e estabelecidas em testes com as bactérias S. aureus e K. pneumoniae. O teste de citotoxicidade das membranas de TPU foi executado e numa avaliação inicial foi observada a sua biocompatibilidade.
Title in English
Development of polyurethane composite membranes by electrospinning process.
Keywords in English
Biomaterials
Electrospinning
Polyurethane
Silver
Zinc Oxide
Abstract in English
The aim of this study is to develop nanostructured polyurethane composite membranes which have antibacterial properties, high porosity and high air permeability, suitable for medical applications. Membranes of thermoplastic polyurethane (TPU) having silver and zinc oxide particles as additives were prepared by electrospinning. The impact of the solvents nature on the electrospinning process was studied. The best results were obtained using a mixture of tetrahydrofuran (THF) and dimethylformamide (DMF), at 50:50 ratio. Viscosity and electrical conductivity of the solutions were measured. Morphology of the membranes formed by the fibers was verified using optical microscopy and scanning electron microscopy, and fibers presenting diameters from 250 to 800 nanometers were observed. The presence of silver and zinc oxide particles in the membranes was confirmed using energy dispersive X-ray spectrometry and wide angle X-ray diffractometry. Antibacterial properties of the membranes were evaluated by testing its activity against suspensions of S. aureus and K. pneumoniae. Additionally, cytotoxicity tests were performed for initial evaluation of the biocompatibility of the TPU membranes having silver as additive.
 
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Publishing Date
2015-01-12
 
WARNING: The material described below relates to works resulting from this thesis or dissertation. The contents of these works are the author's responsibility.
  • HARADA, N. S., et al. QUANTIFYING ADSORPTION OF HEPARIN ON PVC SUBSTRATE USING ATR-FTIR [doi:10.1002/pi.1685]. Polymer International [online], 2005, vol. 54, nº 1, p. 209-214.
  • SINJI HARADA, NIKOLAS, et al. Polyurethane Composite Membranes [doi:10.4028/www.scientific.net/MSF.775-776.3]. Materials Science Forum [online], 2014, vol. 775-776, p. 3-8.
  • WANG, S. H., et al. Coating and Characterization of poly(vinyl chloride) tubing surface with heparin for extracorporeal circulation. In 7th World Conference on biodegradable polymers and plastics, Tirrrenia, 2002. 7th World Conference on biodegradable polymers and plastics.Pisa : Dept. Chem. and Ind. Chem. - University of Pisa - Italy, 2002. Abstract.
  • WANG, S. H., et al. Quantitative spectroscopy of heparin on polyvinyl chloride) tubing surface. In I SBPMAT - 1st Brazil-MRS Meeting, Rio de Janeiro, 2002. Program and Book of Abstracts of 1st Brazil-MRS Meeting.RJ : SBPMAT, 2002. Abstract.
  • WANG, S. H., et al. TRATAMENTO DE SUPERFÍCIE DE TUBOS DE PVC PARA CIRCULAÇÃO SANGÜÍNEA EXTRACORPÓREA, UTILIZANDO O PROCESSO DE HEPARINIZAÇÃO. In 6º CBPOL - IX International Macromolecular Colloquium, Gramado, 2001. Anais do 6º CBPOL - IX International Macromolecular Colloquium.Sao Carlos : ABPOL, 2001.
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