Banca de QUALIFICAÇÃO: FERNANDA YUKARI DE SOUZA SAKUMA

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : FERNANDA YUKARI DE SOUZA SAKUMA
DATE: 29/06/2021
TIME: 14:00
LOCAL: remota
TITLE:

CELLULOSE NANOFIBRILS AND NANOSILICA FILMS FROM AÇAÍ WASTE WITH POTENTIAL FOR ECO-PACKAGING

KEY WORDS:

Euterpe oleraceae. Nanoparticles. Lignocellulosic fibers. Silicon. 

PAGES: 35
BIG AREA: Ciências Agrárias
AREA: Recursos Florestais e Engenharia Florestal
SUMMARY:

The açaí production chain is responsible for generating large amounts of wastes composed of lignocellulosic fibers and seeds, usually discarded and accumulated in the environment. A sustainable alternative for reuse is the generation of biotechnological products. The objective of the work was to develop biodegradable films from the combination of two components from açaí waste, cellulose nanofibrils, and silica nanoparticles. The fibers were subjected to alkaline treatments with sodium hydroxide (NaOH) and bleaching with oxygen peroxide (H₂O₂). The production of nanocellulose occurred through mechanical defibrillation of the fibers, with five passes through the grinder and film formation by the casting method. 100 g of each waste composition were used to obtain silica: a) seeds + lignocellulosic fibers, b) lignocellulosic fibers, and c) peeled seeds. The samples were refluxed with Soxhlet solution (2N) HCl and then heat treated with a heating rate of 13 °C.min^-1 until reaching a temperature of 650 °C, maintained for 3 h. For the production of nanosilica, 2 g of silica from each waste composition will be subjected to soxhlet refluxing with (6N) HCl solution. The formation of sodium silicate (‎Na₂SiO₃) will be through magnetic stirring in 2.5N NaOH solution, forming the nanosilica gel with the addition of sulfuric acid (H2SO4) that will be dried in an oven. Cellulose nanofibril nanocomposites will be produced with different concentrations of nanosilica (2.5%, 5%, and 10%). The characterization will be performed using optical microscopy and SEM on fibers, TEM on cellulose fibers and nanofibrils, FTIR and X-ray diffraction on nanosilica and physical properties of films. Cellulose nanofibril films without nanosilica had 64.12 ± 9.4% water absorption, 13.48 ± 3.92% water solubility, and 11.23 ± 0.32% water vapor permeability. As a result, it is expected that the nanocomposite films will present more resistant physical and mechanical properties when incorporating different contents of silica nanoparticles. It is also expected to determine the yield in silica production from initial masses and nanosilica from silica.

BANKING MEMBERS:
Presidente - 2410727 - LINA BUFALINO
Interno - 1134991 - THIAGO DE PAULA PROTASIO
Externo à Instituição - JARDEL PINTO BARBOSA
Externa à Instituição - CARLA PRISCILLA TÁVORA CABRAL