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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A residue-free and effective corncob extrusion pretreatment for the enhancement of high solids loading enzymatic hydrolysis to produce sugars
2022 - JOSE, ALVARO H.M.; MOURA, ESPERIDIANA A.B.; RODRIGUES JUNIOR, DURVAL; KLEINGESINDS, EDUARDO K.; RODRIGUES, RITA C.L.B.
To convert biomass into biofuel, pretreatment is the first stage required to de-structure lignocellulose – twin-screw extrusion is one of the viable pretreatment technologies. The enzymatic hydrolysis of corncobs pretreated with twin-screw extrusion to obtain sugar was evaluated. Corncob extrusion (115–130 °C; 14 rpm) was enhanced through the employment of additives (water and glycerol, 25:25, % w/w). By reproducing the response surface methodology (RSM) technique, the maximized glucose productivity (0.69 g L−1 h−1) and conversion of cellulose to glucose (90.4 % w/w), as well as hemicellulose to xylose and arabinose (44.0 % w/w) were established with the dosage of the commercial enzymatic complex Cellic Ctec2 (32 FPU/gdry lignocellulosic material) and solids loading (17.8 % w/w). Total sugar yield was of 471 kg (glucose 323 kg; xylose and arabinose 148 kg) for a dried corncob ton. Kinetic constants of the Michaelis-Menten model, Vmax and Km, for converting cellulose to glucose were of 6.00 % (w/w)/h and 22.59 gcellulose/Lsolution, respectively. A residue-free and effective corncob extrusion pretreatment enhanced high solids loading enzymatic hydrolysis to achieve a glucose-rich solution.
Recycling expanded polystyrene with a biodegradable solvent to manufacture 3D printed prototypes and finishing materials for construction
2022 - BARTOLOMEI, SUELLEN S.; SILVA, FELIPE L.F. da; MOURA, ESPERIDIANA A.B. de; WIEBECK, HELIO
The amount of plastic waste generated is causing damage to the environment, such as sea and soil pollution, and one of the alternatives for disposing of polymers is recycling. This work proposes recycling expanded polystyrene using a biodegradable solvent, its plastification with glycerol, and the preparation of the composite with post-consumer recycled gypsum for applications to manufacturing by 3D printing and for finishing materials for construction. Specimen for tensile testing and shore D hardness were prepared by injection process and by 3D printing. In addition, Thermogravimetric (TG), Fourier-transform infrared spectrometry (FTIR), Differential scanning calorimeter, Scanning electron microscope (FESEM) analyses, and flame propagation tests were also carried out. TG and FTIR analyses show that the recycling process did not degrade the material, and the addition of glycerol and gypsum improved the thermal stability of the composite. The mechanical properties of the injected and 3D printed samples with gypsum were similar, due to the dimensional stability of the manufactured filament, which improved the speed and quality of the specimen printing. The increase in ductility and the reduction in the glass transition temperature showed that the recycled expanded polystyrene (RPS) were effectively plasticized with the addition of 2 wt% glycerol, preserving their flame self-extinguishment when subjected to the flame propagation test. Due to these properties, the plasticized RPS can be used to manufacture articles for finishing in civil construction, and the RPS composite can be used to manufacture 3D printed prototypes.
Lignin‑based polyethylene films with enhanced thermal, opacity and biodegradability properties for agricultural mulch applications
2021 - CHIAPPERO, LUCIO R.; BARTOLOMEI, SUELLEN S.; ESTENOZ, DIANA A.; MOURA, ESPERIDIANA A.B.; NICOLAU, VERONICA V.
Lignins are promising alternative raw materials for biocomposites due to their renewability, low cost and abundance. In this work, the use of (softwood and hardwood) Kraft lignins in the development of LLDPE/lignin films for agricultural mulch applications is studied. Processable blends were obtained from unmodified softwood lignin (SW) and from hardwood lignin modified by esterification (HWE). LLDPE was pelletized with (2.5%, 5% and 10%) lignin with particle size between 38 and 75 μm and flexible films were blown extruded. Processable extrusion blends showed temperature differences lower than 20 °C between the Tg of lignin and the melting temperature of LLPDE. Films from neat LLPDE and with 2.5% of HWE and up to 5% SW exhibited statistically comparable (≅ 349%) values of ductility. Ester groups present in lignin improve weight loss of lignin-based blends after soil buried test.
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.