Banca de DEFESA: BRUNO HENRIQUE DOS SANTOS

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : BRUNO HENRIQUE DOS SANTOS
DATA : 18/02/2020
HORA: 09:00
LOCAL: Campus Santo André
TÍTULO:

Characterization of thermoplastic starch composites with sugarcane bagasse fibers

PÁGINAS: 114
GRANDE ÁREA: Engenharias
ÁREA: Engenharia de Materiais e Metalúrgica
SUBÁREA: Materiais Não-Metálicos
ESPECIALIDADE: Polímeros, Aplicações
RESUMO:

Brazil is a large generator of lignocellulosic waste from agroindustry. As a result, research has been increasing with a view to environmentally acceptable disposal of these wastes. An alternative is to replace synthetic fibers as a dispersed phase in polymeric biocomposites. In this project, TPS composites and sugarcane bagasse residues were prepared by extrusion and compression molding. The effect of using fibers of different sizes and the alkaline treatment of fibers with sodium hydroxide and sodium sulfite on the properties of composites was evaluated. The size ranges used were: <0.595 mm, 0.595 - 0.297 mm, 0.297 - 0.250 mm and> 0.250 mm; and the fibers were treated for 30, 60, 120 and 240 min. Fibers, TPS and composites were characterized by chemical, mechanical, thermal and morphological analyzes. The fibers with different size ranges had the same chemical composition and similar thermal properties. However, the crystallinity index and aspect ratio values are higher for larger fibers, and the absorption and moisture content values are higher for smaller fibers. The variation of the alkaline treatment period did not significantly change the thermal properties, morphology, moisture content or chemical composition of the treated fibers. It was found that 30 min of treatment was sufficient to remove 56% of hemicellulose and 73% of lignin indicating the efficiency of alkaline treatment, and there was no increase in removal of these components after this period. TPS composites with 10% by weight (% m / m) of sugarcane bagasse fibers with different sizes showed similar mechanical properties to TPS. However, the composite with smaller fibers (<595 mm) tended to obtain better mechanical properties. The composite with 10% w / w fiber (<595 mm) and treated for 30 min showed similar properties to the composite using untreated fiber. Composites with 20, 30 and 40% w / w fiber (<595 mm) without treatment were prepared and composites with 20 and 30% w / w fiber (<595 mm) treated for 30 min. The 30% w / w fiber composite (<595 mm) is treated for 30 min. presented a 135% increase in maximum tension, 770% increase in elastic modulus compared to TPS and thermal stability of ~ 20 ° C higher than pure TPS.

MEMBROS DA BANCA:
Presidente - Interno ao Programa - 1763443 - MARCIA APARECIDA DA SILVA SPINACE
Membro Titular - Examinador(a) Externo ao Programa - 2347767 - MATHILDE JULIENNE GISELE CHAMPEAU FERREIRA
Membro Titular - Examinador(a) Externo à Instituição - BALTUS CORNELIUS BONSE - FEI
Membro Suplente - Examinador(a) Externo ao Programa - 1730526 - SUEL ERIC VIDOTTI
Membro Suplente - Examinador(a) Externo ao Programa - 1762438 - JEAN JACQUES BONVENT