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Dissertations |
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1
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TÂNIA EVYLLYN DIAS DA SILVA
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DEVELOPMENT OF RECYCLED PET/WOVEN PET BLEND FOR TEXTILE APPLICATIONS
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Advisor : EDSON NORIYUKI ITO
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COMMITTEE MEMBERS :
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EDSON NORIYUKI ITO
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KESIA KARINA DE OLIVEIRA SOUTO SILVA
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IRIS OLIVEIRA DA SILVA
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JOSÉ KAIO MAX ALVES DO RÊGO
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Data: Mar 31, 2023
Ata de defesa assinada:
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Show Abstract
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Plastic consumption has generated some environmental problems such as contamination of the environment. Plastic waste resulting from inappropriate disposal, due to its characteristics, mainly due to its form factor, has led to an increase in the mortality of life in rivers and seas. In light of these problems, it is necessary to develop actions that reduce these impacts, such as the recycling of these materials and the use of circular economy, which exposes a concern regarding the life cycle of products and their applications. The work aimed to develop a filament applicable in the textile industry, resulting from the combination of recycled poly(ethylene terephthalate) (PETR) from bottle grade and woven PET (PETT) from the clothing industry. The PETR/PETT binary blend with and without the use of ethylene-methyl acrylate-glycidyl methacrylate copolymer (EMA-GMA) as a chain-extending agent was plasticized and homogenized in a twin screw extruder with d = 16 mm and l/d = 40, varying the compositions in 10 wt% of PETT in PETR until the composition fo 100 wt% of PETT and, using 3 wt% of EMA-GMA in the formulations of these mixtures. After the production of polymeric mixtures, rheological characterizations were carried out by melt flow index (MFI) measurements, thermal characterization by differential scanning calorimetry (DSC), physicochemical characterization by X-ray fluorescence (FRX), mechanical characterization by uniaxial tensile and, morphological characterization by scanning electron microscopy (SEM). Previous work showed that the EMA-GMA copolymer showed evidences of reaction with PET and the results of the characterizations in this work corroborated the results obtained previously. The MFI and tensile test results corroborated the optimization and definition of the best compositions to be processed in the single screw extruder with d = 16 mm and l/d = 26, aiming at the production of continuous filaments. Through the MFI evaluated the fluidity as a function of temperature and the flow stability of the polymeric mixtures and, the results of tensile strength, elongation at break and modulus of elasticity showed the materials that presented the best results to be selected and used in the production of textile filaments. FRX analysis performed on PETT identified the presence of titanium dioxide (TiO2), which is used as a white pigment in clothes. The photomicrographs obtained by SEM showed phase separation between the two types of PET, recycled bottle grade and woven. The pure polymers were processed under the same conditions, having the same thermal history and were used as a reference for the final quality of the filaments produced from the polymeric mixtures. The results of the characterizations showed that the mixtures with 60, 70 and 90 wt% of PETT were the materials that presented the best results to be applied in the manufacture of textile filaments and, finally, measurements of the titration and measurements of the thickness of these textile filaments by SEM were carried out.
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2
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MATHEUS GOMES SANTIAGO
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THE PHYSICAL PROPERTIES OF COTTON AND POLYESTER AND ITS INFLUENCE ON THE QUALITY OF THE YARN PAMP 65/35 NE=36/1
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Advisor : MARCOS SILVA DE AQUINO
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COMMITTEE MEMBERS :
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MARCOS SILVA DE AQUINO
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JOSE IVAN DE MEDEIROS
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MOISES VIEIRA DE MELO
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RUBENS CAPISTRANO DE ARAUJO
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Data: Apr 7, 2023
Ata de defesa assinada:
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Show Abstract
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ABSTRACT
The art of spinning is such an ancient and important tradition in today's world that it has been industrialized to this day. Its end result is yarn, whose product is obtained from natural and synthetic fibers, or their various types of mixtures. A good quality yarn has certain characteristics that differentiate it from others. An important characteristic is its minimal effect on the formation of pilling or small “balls” of intertwined fibers, also known as neps. Faced with this concern, we decided to develop this research, with the objective of knowing the influence of the physical properties of cotton and polyester on the quality of PAMP 65/35 Ne=36/1 yarn. Thus, it was possible to graphically describe the behavior of the physical properties of cotton and polyester, such as percentage of impurities, percentage of short fibers, fiber fineness and length within the production cycle. This research was carried out in partnership with a Company with a data collection an intentional non-probabilistic sampling was applied, also applying processing and analysis of the information was carried out using the significance value (Sig) for the hypothesis test and the coefficient of Spearman correlation (Rho). It was concluded that with the contrast of the results obtained with other similar studies, a great similarity and a good contribution of the work to the textile industry can be found.
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3
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CRISLAYNE FELIPE CAMPOS
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USE OF FUNCTIONALIZED CALOTROPIS PROCERA FIBER FOR ADSORPTION OF DYE FROM TEXTILE EFFLUENTS
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Advisor : KESIA KARINA DE OLIVEIRA SOUTO SILVA
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COMMITTEE MEMBERS :
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ANDRÉA FERNANDA DE SANTANA COSTA
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FABRÍCIO MAESTÁ BEZERRA
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JOSE HERIBERTO OLIVEIRA DO NASCIMENTO
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KESIA KARINA DE OLIVEIRA SOUTO SILVA
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Data: Jun 7, 2023
Ata de defesa assinada:
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Show Abstract
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The present study used Calotropis procera fiber as a natural adsorbent for the reactive dye present in textile effluents. The justification for choosing this dye was due to its wide use in dyeing processes on cotton substrates. Due to the lack of affinity of the fiber with water, the fiber was submitted to a functionalization with chitosan, aiming at a better adsorption and interaction between fiber and effluent. The adsorbents used, for the most part, are not biodegradable, which is currently not interesting for the environment, the current search is for environmentally friendly materials. The Calotropis fiber was selected due to its high predominance in the northeast region of Brazil, because it is considered a weed and because it has internal voids that help in the adsorption process, in addition to being biodegradable. The use of chitosan as a functionalizing agent is justified by its non-toxicity, biocompatibility and biodegradability. The fiber characteristics were evaluated with the aid of SEM, FTIR and XRD analysis. The effluent was characterized through the environmental parameters of pH, turbidity, conductivity, dissolved oxygen (DO) and UV-Vis absorbance, these analyzes were performed before and after contact with the fiber. The SEM analyzes demonstrated that Calotropis has a smooth surface, without convolutions and internally hollow, even after its functionalization, the infrared analyzes indicated the presence of carboxylic and hydroxyl groups. The adsorption efficiency was analyzed using the effluent generated by dyeing with reactive dye BLUE BG-R CONC, obtaining a removal of 100%. The results showed that Calotropis procera functionalized with chitosan is suitable for the adsorption of reactive dye, being a simple alternative, environmentally correct, being a potential method for removing color from textile effluents, contributing to the preservation of the environment.
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4
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ERIADNA GOMES DA SILVA MARTINS
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DEGRADATION OF FULL-BODY HARNESSES AGAINST FALLS AFTER USE BY ACTIVITY FIELDS.
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Advisor : JOSE IVAN DE MEDEIROS
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COMMITTEE MEMBERS :
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JOSE IVAN DE MEDEIROS
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KESIA KARINA DE OLIVEIRA SOUTO SILVA
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FAGNER ALEXANDRE NUNES DE FRANCA
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FERNANDA STEFFENS
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Data: Aug 24, 2023
Ata de defesa assinada:
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Show Abstract
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Full-body harnesses are used as protective equipment in order to minimize the consequences of high falls and require good mechanical properties to provide the necessary protection to the user. There are few studies about the characterization of used full-body harnesses in order to identify and quantify the loss of degradation after its usage time. Previous studies showed those protective equipments lose their protective properties during service life, caused by several destructive factors as well as UV, dust, chemicals, temperature changes and humidity, as direct contact with sharp objects and rough surfaces. The objective of this work is to present degradations found in full-body harnesses after use, relating these defects to the types of activity to which they were exposed. The methodology used is based on the use of full body harnesses samples against falls used by workers in several companies, performing a visual inspection, characterization of textile materials, static and dynamic tests on said samples. The results confirm several types of degradation found in previous research and demonstrate that most of the defects found are related to corrosion of metallic elements (90%), dirt (50%), and wear on the tapes (20%). In those samples collected in industry, a greater diversity of defects and dirt were found, while in civil construction only dirts from cement was found. In the energy and telecommunications sectors, defects were found in dorsal support elements and in the legs, in addition to wear on the tapes in 80% of the samples, which may be related to the daily frequency of use of Personal Protective Equipments to climb stairs and poles. Finally, all used full body harnesses against falls studied were approved in dynamic tests, but there was a loss of resistance of 3.46%, proven through static resistance tests.
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5
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ANDREZA BERNARDES DA SILVA
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TiO2 QUANTUM DOTS: AN INNOVATIVE NANOMATERIAL FOR TEXTILE MATERIALS FUNCTIONALIZATION
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Advisor : JOSE HERIBERTO OLIVEIRA DO NASCIMENTO
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COMMITTEE MEMBERS :
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AMANDA MELISSA DAMIAO LEITE
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CARLA MANUELA PEREIRA MARINHO DA SILVA
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ELISAMA VIEIRA DOS SANTOS
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JOSE HERIBERTO OLIVEIRA DO NASCIMENTO
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NIVALDO FREIRE DE ANDRADE NETO
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PIERRE BASILIO ALMEIDA FECHINE
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Data: Oct 13, 2023
Ata de defesa assinada:
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Show Abstract
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The UN's 2030 agenda aims to achieve this sustainability through 17 objectives, namely: industry, innovation and infrastructure; clean water and sanitation. In this sense, it is necessary to search for sustainable materials, in particular, to act in the treatment of water in the textile industry, which is one of the largest consumers of water in its chemical processes and with a low reuse rate and, consequently, generating a high load. of polluting effluents. Thus, nanomaterials are widely studied and used for applications that minimize this problem. One of the applications is via photocatalysis processes, due to the high efficiency of these nanostructures due to their surface area, such as: TiO2, ZnO and other semiconductors. Other emerging nanomaterials are nanoparticles with reduced size in the range of 1-10 nanometers, which, due to their size, undergo quantum confinement and are therefore called quantum dots. The main problem involving TiO2 quantum dots is the agglomeration of particles in the medium, which makes their use in photocatalysis complex, since a secondary treatment is necessary to recover it. In this proposed study, the objective was to evaluate the applicability of TiO2 quantum dots (TiO2 PQs) immobilized in textile fibers for potential photocatalytic application. The synthesis of PQs TiO2 was performed via solgel and in the first stage of this study, immobilized on soybean fibers by the layer-by-layer method using chitosan as a cationizing agent. The photocatalytic evaluation was carried out using a concentration variation (2 to 8 ppm) of rhodamine B. In the second study, a Box-Behken-type factorial design was used where the variables: TiO2/Au ratio (%), temperature, time and pH of the immobilization solution, having as response variable, the photodegradation of the reactive dye black 5 (C26H25N5O19S6), one of the most used dyes in the textile industry. Soybean and polyamide fabric samples were characterized for their microstructural properties using XRD, XPS, HRTEM-SAED, SEM-FEG as well as colorimetric analyses. The results prove that the obtained quantum dots present a tetragonal crystalline structure, corresponding to the anatase phase, with a size approaching 6 nm. The results of the photocatalysis of the functionalized soy fiber showed excellent photocatalytic efficiency, degrading 2 ppm of Rhb in 120 minutes, with durability of up to 5 cycles of reuse, with a loss of approximately 10% of its photocatalytic efficiency. The polyamide fabric nanocoated with PQs TiO2/Au, presented an efficiency of approximately 100% of photodegradation of 20 ppm of the RB5 dye, in 240 minutes and with reuse stability in 5 consecutive cycles. Therefore, the application of quantum dots in textile fibers as functionalization agents is a promising way to obtain flexible surfaces with excellent photocatalytic properties.
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6
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WANLÍDIA FERNANDES DE ARAÚJO BENEVIDES
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Hydrophobic functionalization on polyester fabrics by Plasma-Enhanced Chemical Vapor Deposition (PECVD)
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Advisor : THERCIO HENRIQUE DE CARVALHO COSTA
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COMMITTEE MEMBERS :
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KLEIBER LIMA DE BESSA
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MICHELLE CEQUEIRA FEITOR
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PETTESON LINNIKER CARVALHO SERRA
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THERCIO HENRIQUE DE CARVALHO COSTA
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Data: Oct 27, 2023
Ata de defesa assinada:
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Show Abstract
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Cold plasma, an ionized gas mixture with a temperature close to room temperature, can be safely used for treatments on textile substrate surfaces. Plasma treatment can modify textile surfaces, forming superhydrophobic nanometric structures that result in self-cleaning materials. Despite having a hydrophilic nature, polyester textiles inherently exhibit certain levels of hydrophobicity in their fibers. With the aim of further enhancing the water repellency of the polyester textile substrate, nanometric carbon-rich films were deposited using the Plasma-Enhanced Chemical Vapor Deposition (PECVD) technique on small fabric samples, using Xylene (C8H10) and Acetylene (C2H2) as vapor sources, and varying the deposition time. Initially, the samples were treated with acetylene alone, with treatment times set at 10, 15, and 20 minutes. The second treatment was carried out using acetylene and xylene, with the same time variations (10, 15, and 20 minutes). Other parameters such as power, flow, temperature, current, and voltage were determined based on the time variations. After the treatment, the samples were subjected to characterizations and evaluated through different experimental techniques, such as water and oil contact angle measurements, scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction analysis (XRD), and Raman spectroscopy analysis. The results obtained indicated that there was polymerization on the fabric surface, creating an ultra-thin carbon-based layer. This layer was composed of apolar groups, which were responsible for providing hydrophobic functionalities to the polyester samples while maintaining oil absorption, even under all treatment conditions.
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7
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DEBORA FONTES PINTO
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PRODUCTION AND CHARACTERIZATION OF NANOFIBROUS MATTERS OF COLLAGEN OBTAINED FROM THE SKIN OF TILAPIA (OREOCHROMIS NILOTICUS) PRODUCED BY BLOW SPINNING IN SOLUTION
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Advisor : THERCIO HENRIQUE DE CARVALHO COSTA
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COMMITTEE MEMBERS :
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MICHELLE CEQUEIRA FEITOR
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MURILO JOSE PEREIRA DE MACEDO
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THERCIO HENRIQUE DE CARVALHO COSTA
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WALDENICE DE ALENCAR MORAIS LIMA
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Data: Oct 30, 2023
Ata de defesa assinada:
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Show Abstract
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The ever increasing demand for research and development of new materials and technologies that can be applied to health is imperative, especially in tissue engineering. The materials and dressings that support wound healing currently on the market are a significant source of non-renewable waste disposal. However, research involving nanotechnology, more sustainable textile finishes, and biodegradable raw materials, with lower cost and environmental impact, is still quite limited, pointing to the need for research and investments in the area. This work aims to contribute to developing porous nanofibrous structures that can be made through cleaner and more efficient techniques, later serving to develop dressings, scaffolds, and extracellular growth matrices. The use of biodegradable, bioabsorbable, and biocompatible polymers, using hydrolyzed collagen extracted from tilapia skin as raw material and blankets produced by solution blow spinning, are proposed alternatives with less environmental impact and functional optimization.
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8
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RAYANE SAORY MEDEIROS DOS SANTOS
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ZINC OXIDE NANOPARTICULES DEPOSITION IN COTTON FABRIC VIA CATHODIC CYLINDRES PLASMA
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Advisor : MICHELLE CEQUEIRA FEITOR
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COMMITTEE MEMBERS :
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MICHELLE CEQUEIRA FEITOR
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MICHELLE DE MEDEIROS AIRES
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THERCIO HENRIQUE DE CARVALHO COSTA
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IGOR OLIVEIRA NASCIMENTO
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THARSIA CRISTIANY DE CARVALHO COSTA
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Data: Oct 30, 2023
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Show Abstract
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The treatment of textile articles with zinc oxide has emerged as a noteworthy technique due to its capacity to confer diverse attributes upon the substrate, thereby enabling the realization of specific technical applications. These applications encompass photocatalysis, antibacterial effects, shielding against ultraviolet (UV) radiation, flame retardancy, hydrophobicity, and electrical conductivity. The direct deposition onto textile materials via plasma represents a promising avenue, notably due to its avoidance of water and the utilization of environmentally hazardous chemical reagents. The principal objective of this research is to effectuate the deposition of zinc oxide nanoparticles onto cotton fabric through plasma processes and subsequently analyze the bactericidal and photocatalytic activities. The cylindrical cathode deposition is a contemporary technique used in this study, whereupon insert zinc oxide compacted cyliderns in the cathodic cage onto plasma reactor. In light of the susceptibility of textile materials to elevated temperatures, cotton fabric samples are positioned externally to the cathode cage, within the reactor’s flange. The study explore of the influence of argon, hydrogen, and an gas mixture over varying treatment durations (1 and 2 hours). The treated samples was analyzed to X-ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FE-SEM) with Energy Dispersive Spectroscopy (EDS), Metilen Blue Photocatalysis and the bacterial activity analysis by Antibiogram and Violet Crystal. The presence of zinc is not found via XRD analysis, but is demonstrable through EDS, with notably higher proportions detected in samples treated exclusively with hydrogen. The visualization of nanoparticle presence via SEM is precluded due to limitations associated with the utilized magnification scale, because a higher scale damages the fabric cotton. All treated samples exhibits methylene blue degradation, with the most pronounced effect observed in the instance of samples treated solely with hydrogen gas over 2 hour. Crystal violet assays and antibiogram testing was carried on cultures of Methicillin-Resistant Staphylococcus Aureus (MRSA) and Resistent Carbapenemase Pseudomonas Aeruginosa (KPC+), representing gram-positive and gram-negative bacteria classifications of paramount concern, as identified by the World Health Organization (WHO). Crystal violet assays manifest inhibition of bacterial proliferation across all samples, save for Pseudomonas aeruginosa in the fabric treated exclusively with argon gas over a 2 hour interval. The most notable inhibition is in the case of Staphylococcus Aureus, achieving an approximate 40% reduction in growth within fabrics treated solely with hydrogen gas. Antibiogram reveals the formation of a well-defined inhibition zone in the sample subjected to hydrogen gas treatment for 2 hours, while a modest inhibition zone is also observed in instances of hydrogen gas treatment for 1 hour and the gas mixture treatment over a 2 hour duration. The results of this study indicate the formation of a thin film on the cotton fabric surface with photocatalytic and antibacterial effects, particularly effective against gram-positive bacterial strains.
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9
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SUZANNA RANI CRISTINA ALVES DE SOUSA
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SYNTHESIS OF HYBRID MEMBRANE OF POLYSUPHONE WITH ZINC OXIDE FOR CLEANING TEXTILE EFFLUENTS
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Advisor : AMANDA MELISSA DAMIAO LEITE
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COMMITTEE MEMBERS :
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AMANDA MELISSA DAMIAO LEITE
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FABRÍCIO MAESTÁ BEZERRA
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KALINE MELO DE SOUTO VIANA
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KESIA KARINA DE OLIVEIRA SOUTO SILVA
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Data: Nov 8, 2023
Ata de defesa assinada:
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Show Abstract
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Due to the large volume of effluents from the textile industry, which causes environmental contamination of water bodies, it is necessary to take treatment measures for the reuse or correct disposal of these effluents. The objective of this work is to produce a polysulfone (PSU) and zinc oxide (ZnO) membrane for decontamination of textile effluents from the dyeing stage. To produce pure and hybrid membranes, the phase inversion technique was used. The membranes produced were analyzed by FTIR and XRD. The results of the diffractogram of the membranes showed peaks characteristic of the PSU. The spectrum in the infrared region of the hybrid membranes showed characteristic polysulfone bands superimposed on the characteristic ZnO bands. The membranes will also be characterized by scanning electron microscopy and thermogravimetric analysis and tested for their applicability in cleaning synthetic textile effluent for efficiency evaluation, given the bactericidal properties presented by ZnO.
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10
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ISABELA SILVA SAMPAIO
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Development of a nonwoven based on kapok fiber and PVAc
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Advisor : SALETE MARTINS ALVES
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COMMITTEE MEMBERS :
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SALETE MARTINS ALVES
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IRIS OLIVEIRA DA SILVA
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RAUL MANUEL ESTEVES DE SOUSA FANGUEIRO
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Data: Nov 15, 2023
Ata de defesa assinada:
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Show Abstract
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The use of synthetic materials to manufacture surgical mask filters is extremely common in the textile industry. However, with the search for environmentally friendly and sustainable raw materials, there is great interest in using these materials in nonwovens. Therefore, the objective of this project is to develop a kapok and PVAc nonwoven fabric and evaluate its effectiveness as a filtering material for PFF masks. A 1:4 solution of distilled water to PVAc was prepared by stirring for 15 minutes, then impregnated and sprayed onto the different mats formed. The filters were consolidated by pressing for 24 hours and dried at 60°C for 2 hours. Chitosan was also added to some samples to evaluate the bacterial effect of its insertion, aiming to guarantee effectiveness in nationally approved tests. However, the results showed that only kapok and PVAc nonwovens had positive responses in inhibiting bacterial proliferation, while other nonwovens made of kapok, PVAc and chitosan had no effect. Air permeability and grammage tests were also carried out in the laboratory with satisfactory results for all filters. It can be seen that the greater the amount of kapok fiber, the greater the resistance of the nonwovens, and that low resistance is associated with high elongation. Analyzes such as XRD, FTIR and SEM-FEG were also carried out to observe the morphology and structure of the developed materials.
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