RENATA DOREA DA SILVA COIADO
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Resumo IPEN-doc 26962 Residues from agroindustry as reinforcement in foams based on PBAT/PLA blend2017 - FREITAS, TARIK; COIADO, RENATA; LAZO, GISELE; OLIVEIRA, RENE; MOURA, ESPERIDIANANowadays, agroindustry residues have attracted great attention in both the academic and industrial worlds. In fact, biodegradable polymers reinforced with residues derived from renewable sources, as avian eggshell waste and ashes from the burning of sugarcane bagasse are economically and ecologically attractive materials to produce a new class of bio-products with eco attributes, which make them environmentally friendly, completely degradable and sustainable. In Brazil, the food industry generates every year huge amounts of avian eggshell waste, an industrial byproduct containing 95 % of calcium carbonate, and its disposal constitutes a serious environmental hazard. Tons of ashes are produced from the burning process of sugarcane bagasse to produce energy in Brazilian sugar and bioethanol industries. These ashes, which are not rich in nutrients for the crop, are usually mixed with organic fertilizers or disposed of in nature without efficient management. However, these ashes containing about 94 % of silica. This study aims to the development of bio-foams from PBAT/PLA blend reinforced with bio-calcium carbonate nanoparticles from eggshells and green-silica nanoparticles. Composites were obtained by melting extrusion process, blending PBAT/PLA with 3 % of bio-calcium carbonate nanoparticles and 3 % of green-silica nanoparticles. The composites were then extruded in a Rheomex 332p single special screw for foaming. Samples were submitted to tensile and compression tests, MFI, DSC, XRD and SEM-FEG analyses.Capítulo IPEN-doc 25009 Polymer blend based on recycled polyethylene and ethylene vinyl acetate copolymers reinforced with natural fibers from agricultural wastes2017 - COIADO, RENATA D.S.; LAZO, GISELE D.; OLIVEIRA, RENE R.; RODRIGUES, RITA C.L.B.; MOURA, ESPERIDIANA A.B.Agricultural residues, which are produced with large quantities annually throughout the world, may be used as reinforcement plastic to replace the wood and produce particleboard for application in the development of low cost construction elements and reduced environmental impact. The main aims of this study was to investigate the effects of agricultural wastes and glass residues addition on the properties of recycled-HDPE/EVA blend for use in particleboard manufacture. The recycled-HDPE/EVA blend reinforced with corncob fiber (15 wt%), coffee parchment (15 wt%) and glass residues (1 wt%) were processed by melt extrusion, using a twin screw extruder and injection molding machine to obtain specimen test samples. The samples were characterized by mechanical test, XRD, TG, DSC, and FE-SEM analysis to understand the nature of interaction between the fillers reinforcement and recycled-HDPE/EVA blend matrix and their properties were discussed.Artigo IPEN-doc 23926 Evaluation of the Poly (Lactic Acid) and calcium carbonate effects on the mechanical and morphological properties in PBAT blends and composites2017 - NUNES, EDILENE de C.D.; SOUZA, ALANA G. de; COIADO, RENATA D.S.; MOURA, ESPERIDIANA A.B.; ROSA, DERVAL dos S.In this study, the effect of the organic (poly(lactic acid)) and the inorganic (calcium carbonate (CaCOR3R)) fillers were evaluated in mechanical, thermal, morphological and surface properties of the poly(butylene adipate-co-terephthalate) (PBAT) matrix. Mechanical results showed that the fillers has an influence on the PBAT matrix. The use of CaCOR3R showed higher elongation at break than PLA. However, the blends showed higher elastic modulus, resulting in greater stiffness to the PBAT matrix. Both fillers thermally destabilized the matrix. The morphological properties showed a uniform dispersion of the fillers in the composites and blends, however it is weaker with PLA. Because the PBAT matrix surface is, intrinsically, hydrophobic, the composites presented a smaller degree of hydrophobicity, while the PLA makes the blends hydrophilic.