ESPERIDIANA AUGUSTA BARRETOS DE MOURA

ESPERIDIANA AUGUSTA BARRETOS DE MOURA

(Fonte: Lattes)

Resumo

Graduated in Chemical Engineering at Faculdade Oswaldo Cruz (1983), Master in Nuclear Technology - Applications at IPEN / USP (1999), Ph.D. in Nuclear Technology - Applications at IPEN / USP (2006) and Post-Doctorate at Center for Advanced Materials ( T-CAM) from Tuskegee University, AL, USA. The main lines of research are: Synthesis of metallic nanoparticles; Obtaining and characterization of nanoparticles from mineral activity and agroindustry residues; Micro and nanofiller functionalization; Synthesis and reduction of graphene oxide; Development and modification of composite materials based on conventional and biodegradable polymers with vegetable fibers, micro and nanofillers of renewable origin; Development of biodegradable, active and intelligent plastic packaging for food, cosmetics, medical and pharmaceutical products; Development of conductive polymeric materials; Development of biomaterials for application in the regeneration of bone and dental tissue. (Text obtained from the Currículo Lattes on October 8th 2021)

Possui graduação em Engenharia Química pela Faculdade Oswaldo Cruz (1983), mestrado em Tecnologia Nuclear ? Aplicações pelo IPEN/USP (1999), doutorado em Tecnologia Nuclear ? Aplicações pelo IPEN/USP (2006) e Pós-Doutorado no Center for Advanced Materials (T-CAM) da Tuskegee University, AL, USA. As principais linhas de pesquisa são: Síntese de nanopartículas metálicas; Obtenção e caracterização de nanopartículas a partir de resíduos da atividade mineral e da agroindústria; Funcionalização de micro e nanocargas; Síntese e redução de óxido de grafeno; Desenvolvimento e modificaçao de materiais compósitos baseados em polímeros convencionais e biodegradáveis com fibras vegetais, micro e nanocargas de origem renovável; Desenvolvimento de embalagens plásticas biodegradáveis, ativas e inteligentes para alimentos, cosméticos, produtos médicos e farmacêuticos;Desenvolvimento de materiais poliméricos condutores; Desenvolvimento de biomateriais para aplicação na regeneração de tecidos ósseos e dentários. (Texto extraído do Currículo Lattes em 08 out. 2021)

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Enhanced miscibility of PBAT/PLA/lignin upon γ-irradiation and effects on the non-isothermal crystallization
2022 - BARROS, JANETTY J.P.; SOARES, CARLOS P.; MOURA, ESPERIDIANA A.B. de; WELLEN, RENATE M.R.
Lignin is natural and renewable polymer, the second most abundant on Earth. Properly used it can reduce synthetic and oil based materials in addition to contributing to the biodegradable systems. In this work, the kraft lignin was subjected to gamma radiation at absorbed doses of 30, 60, and 90 KGy in order to increase the interaction with “Poly(butylene adipate-co-terephthalate) (PBAT)/Poly(lactic acid) (PLA)” blend (Ecovio®). PBAT/PLA/lignin blends with 10% of the weight of lignin were produced by extrusion using twin-screw extruder and characterized by Fourier transform infrared spectroscopy (FTIR), Differential scanning calorimetry (DSC), and Field emission scanning electron microscopy (FE-SEM). FTIR spectra showed partial miscibility between PBAT/PLA and lignin, most due to the hydrogen bond between PBAT/PLA carbonyl and lignin hydroxyl, being intensified in irradiated lignin compounds. As evidenced on DSC scans, in PBAT/PLA/irradiated lignin the crystallization peak was shifted to lower temperatures and the crystallization rate decreased. Crystallization kinetics was modeled using Pseudo Avrami, and isoconversional models of Friedman and Vyazovkin. Pseudo-Avrami displayed linearity deviation at beginning and crystallization ending due to the nucleation and secondary crystallization, while from Friedman and Vyazovkin the activation energy (Ea) was higher for PBAT/PLA/irradiated lignin 30 KGy, characterizing crystallization with higher energy consumption. FE-SEM images showed better dispersion and miscibility in PBAT/PLA/irradiated lignin. The results indicate that the irradiation of Kraft lignin promotes miscibility and compatibility of PBAT/PLA/lignin.
Mechanical and thermal properties of modified Georgian and Brazilian clay infused biobased epoxy nanocomposites
2021 - KODALI, DEEPA; UDDIN, MD-JAMAL; MOURA, ESPERIDIANA A.B.; RANGARI, VIJAK K.
This study focuses on the preparation and characterization of nanocomposite system with bio-based epoxy resin (Super SAP 100/1000, contains 37% bio-based carbon content) and natural clays including Georgian clay and Brazilian clay. Georgian clay was surface modified using an ultrasound processing in presence of Decalin. Brazilian clay was modified to organophilic bentonite using quaternary ammonium salts. The resulting nano clay particles were characterized using XRD and TEM to confirm the particle size reduction and uniform distribution. The as-fabricated nanocomposites were characterized using flexure, DMA, TMA and TGA. The flexure analysis showed that the modified clay composites have significant improvement in strength (23–38%) and modulus (28–37%). Delayed thermal degradation was observed from TGA analysis which showed that the major degradation temperatures improved from 7°-25°C. DMA and TMA analysis showed improvements in storage moduli (4–6%) and coefficient of thermal expansion (CTE) (6–64%), respectively. The notable improvement in thermal and mechanical properties suggested the effective dispersion and the high degree of polymer particle interaction. The bio based content present in the Super Sap 100/1000 acts as plasticizer resulting in the extensive ductility of the polymer.
Propriedades térmicas e mecânicas de filmes flexíveis de polietileno e copolímero de etileno e álcool vinílico reforçados com óxido de grafeno
2017 - SANTANA, JULYANA G.; GUVEN, OLGUN; MOURA, ESPERIDIANA A.B.
Os copolímeros de etileno e álcool vinílico (EVOH) são uma família de resinas com excelentes propriedades de barreira a gás de grande importância para a indústria de embalagens para alimentos, o polietileno de alta densidade (HDPE) um polímero hidrofóbico que em mistura com o EVOH, agrega melhores propriedades de barreira e mecânicas a embalagem final. O objetivo deste trabalho foi estudar os efeitos da adição de óxido de grafeno (GO) nas propriedades de filmes flexíveis preparados a partir de uma blenda HDPE e EVOH (HDPE/EVOH). Que foram processados, utilizando-se uma extrusora dupla rosca corrotante, e posteriormente os materiais processados foram alimentados a uma extrusora balão de laboratório para a obtenção dos filmes flexíveis. Os filmes flexíveis foram caracterizados por meio das análises de DSC, TG, MEV e ensaios de tração e a correlação entre as suas propriedades foi discutida.
Preparation of EVOH/graphene oxide by blown film extrusion – correlation between film properties and graphene oxide addition
2016 - BARREIRA, DAILI A.S.; SANTANA, JULYANA G.; LAZARO, LOURDES Y.; RUIZ, JESUS G.; VALENZUELA-DIAZ, FRANCISCO; GUVEN, OLGUN; MOURA, ESPERIDIANA A.B.
This study reports the preparation of EVOH films reinforced with graphene oxide by twin-screw extrusion and blown film extrusion processing. The preparation of EVOH/Graphene oxide (EVOH/GO) films was carried out in two steps: EVOH with Graphene oxide powder (0-0.5 wt. %) was fed into a co-rotating twin-screw extruder, then the EVOH/GO nanocomposite was transformed into thin films using an extrusion blown film, single screw machine with 25 mm diameter and specimens test samples were obtained. The purpose of this study was to evaluate the correlation between mechanical properties and thermal stability of EVOH/GO films and the amount of graphene oxide added to the EVOH matrix. Tensile tests were conducted using an INSTRON Testing Machine. DSC and TG analysis were used for investigate the thermal stability of EVOH/Graphene oxide films. DSC analysis results showed that melting temperature (Tm), melting enthalpy (Hm) and consequently the degree of crystallinity (Xc) of neat EVOH increased with the incorporation of the 0.1 and 0.5 wt. % of GO. TG of the composites showed a great difference in weight loss and in the onset degradation temperature when compared with the neat EVOH. The more important change was observed for EVOH/GO with 0.2 wt. % GO content that presented an increase of the onset degradation temperature. A significant enhancement of the tensile strength at break of EVOH/GO flexible film without important effects on the elongation at break were also observed, except for EVOH/GO with 0.2 wt. % GO content that presented an important increase in both, tensile strength and elongation at break. It can be concluded that the addition of GO is an effective means to improve the EVOH flexible films properties and led to the obtaining of packaging materials with superior properties suitable for several industrial applications.
Changes in physicochemical, morphological and thermal properties of electron-beam irradiated ethylene-vinyl alcohol copolymer (EVOH) as a function of radiation
2009 - NOGUEIRA, B.R.; ANGEL, V.O.; MOURA, E.A.B.
Investigation on mechanical and thermal behaviours of copolyester/pla blend reinforced with TiOsub(2) nanoparticle
2015 - LIMA, ROBERTA A.; OLIVEIRA, RENE R.; RANGARI, VIJAYA K.; JEELANI, SHAIK; MOURA, ESPERIDIANA A.B.
influence of clay exfoliation on the properties of evoh/clay flexible fims
2015 - MACHADO, MESSIAS dos S.; GODOY, RENATO B.; SILVA, ANDRESSA; LIMA, ROBERTA; OLIVEIRA, RENE R.; VALENZUELA-DIAZ, FRANCISCO; MOURA, ESPERIDIANA
Biodegradable starch/copolyesters film reinforced with silica nanoparticles
2015 - LIMA, ROBERTA A.; OLIVEIRA, RENE R.; WATAYA, CELIO H.; MOURA, ESPERIDIANA A.B.
Evaluation of mechanical properties and DSC study of commercial multilayer PA/PE film treated with e-beam radiation
2005 - ORTIZ, A.V.; MOURA, E.A.B.; COELHO, A.C.V.
Packaging materials have been widely processed by ionizing radiation in order to improve their chemical and physical properties and also for sterilization purposes. Basically, flexible packaging manufacturers apply specific radiation doses to promote cross-linking and scission of the polymeric chains and thus obtain alterations in certain properties of the material. While enhancing a specific property, significant losses may result in others. In this study, we examined the effects of E-beam radiation on a commercial multilayer PA6/LDPE based film, irradiated with doses up to 127 kGy. Food producers mostly use this structure as a thermoforming bottom web for processed meat products. Two weeks after irradiation, tensile strength and elongation of the film were analyzed. Both mechanical properties were again analyzed 18 months after irradiation took place. Significant changes of mechanical properties were observed specially 18 months after irradiation. Once cross-linking and scission are able to affect the material crystalline arrangement and consequently cause properties changes, a DSC ( Differential Scanning Calorimetry) study was carried out for doses up to 130 kGy in order to verify such changes.
Effects of piassava fiber incorporation on the morphological thermal and behaviour of HDPE composite
2011 - SOUZA, THIAGO L.S.; NOGUEIRA, BEATRIZ R.; CHINELLATO, ANNE; DRUMOND, WALKER S.; MOURA, ESPERIDIANA A.B. de