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. Nanopartículas. Fibras. Sílica. 

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

The açaí production chain generates large amounts of wastes composed of lignocellulosic fibers and seeds, generally discarded in the environment, causing an accumulation and raising concerns about its destination, an opportunity to develop sustainable biotechnological products. The objective of the work is to develop biodegradable films from the combination of two components from açaí waste; cellulose nanofibrils reinforced with silica nanoparticles. The fibers underwent alkaline treatments with sodium hydroxide (NaOH) and bleaching in a solution containing 24% H₂O₂ and 4% NaOH. The production of nanocellulose occurred through fiber defibrillation, with five passes through the grinder and film formation by the casting method. 100 g of each waste composition were used to obtain the silica: a) berries + lignocellulosic fibers, b) lignocellulosic fibers, and c) berries. The three samples were refluxed with a Soxhlet solution (2N) HCl and then heat-treated with a heating rate of 13 °C.min^-1 until reaching a temperature of 650 °C. For the production of nanosilica, 2 g of silica from each waste composition will be subjected to treatment in soxhlet 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), and 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 carried out by optical microscopy on fibers and nanosilica, X-ray diffraction on fibers, nanosilica and films, SEM on fibers, and TEM on cellulose fibers and nanofibrils. In the cellulose nanofibril films, water absorption, water solubility, vapor permeability, and density will be determined. As a result, it is expected that the nanocomposite films will present more resistant physical and mechanical properties when different silica nanoparticle contents are incorporated. It is also expected to determine the quality and yield of silica and nanosilica obtained from different waste compositions.

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