Banca de QUALIFICAÇÃO: RANNIER MARQUES MENDONCA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
DISCENTE : RANNIER MARQUES MENDONCA
DATA : 18/05/2018
HORA: 08:00
LOCAL: Sala de aulas do PPGCEM
TÍTULO:

CURE KINETICS OF POLYESTER WITH THE ADDITION OF CUPUACU SHELL POWDER

PALAVRAS-CHAVES:

Polyester, Cure Kinetics, Cupuacu.

PÁGINAS: 106
GRANDE ÁREA: Engenharias
ÁREA: Engenharia de Materiais e Metalúrgica
SUBÁREA: Materiais Não-Metálicos
ESPECIALIDADE: Polímeros, Aplicações
RESUMO:

The growing awareness of environmental issues and the consequent increasingly rigid international legislation in this area have attracted the interest of researchers to the development of materials containing components derived from renewable sources. Among vegetable resources with potential application in the industrial area, cupuaçu (Theobroma grandiforum), a fruit native to the Amazon region, offers pulp and seeds used in the production of food products. In this process, the shell is usually discarded in landfills. This shell has in its composition organic compounds that can affect the curing kinetics of polymer resins. In this sense, the objective of this research was to study the effect of the chemical compounds present in the cupuaçu fruit shell on the curing kinetics of polyester resins. Laser granulometry, Scanning Electron Microscopy (SEM), thermogravimetry, Differential Scanning Calorimetry (DSC), tensile tests, Dynamic-Mechanical Analysis (DMA), reaction kinetics and phytochemistry analyses were performed. According to the results obtained from the kinetic studies by the temperature sweep method, the temperature of the beginning of the cure reaction was shifted as of the percentage of vegetal material was increased, indicating a delay of the reaction process. The vegetable-based additive also affected the degree of conversion throughout the curing process of the unsaturated polyester resin. The activation energies of the reactions were altered when compared to the pure polyester resin: higher activation energies for the samples with 2 wt.% of additive and lower for the samples with 0.5 wt.% and 1 wt.% of additive. Using the isothermal method, it was observed that the phases of the partitions of the raw extracts of the shell also affected the curing process of the polymer resin, suggesting more than one reagent molecule in the vegetable material. The thermogravimetric results confirmed a degradation temperature of the vegetable material at about 300 °C, thus close to that of the pure polymer. The addition of the plant material into the polyester resin did not affect the thermal properties (glass transition temperature and degradation temperature) of the cured polyester resin. Also, the mechanical properties - tensile strength and modulus of elasticity - were not affected significantly by the addition of the shell components.

MEMBROS DA BANCA:
Presidente - 1202134 - JOSE DANIEL DINIZ MELO
Interno - 2042234 - ANA PAULA CYSNE BARBOSA
Externo ao Programa - 1149440 - ROSANGELA DE CARVALHO BALABAN