Banca de DEFESA: ISABELLA DONADELLO DUARTE

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : ISABELLA DONADELLO DUARTE
DATE: 05/05/2023
TIME: 16:00
LOCAL: Sala virtual
TITLE:

Investigation of the healing ability of thermoplastic healing agent in carbon-epoxy composite 

KEY WORDS:

composites; carbon-epoxy; self-healing; prepreg; thermoplastic agent 

PAGES: 75
BIG AREA: Engenharias
AREA: Engenharia de Materiais e Metalúrgica
SUMMARY:

Polymer matrix composites (PMCs) present an exponential growth in structural applications due to its distinct advantages such as high stiffness, strength and lower weight. Still, PMCs are susceptible to damage and degradation during service and environmental exposure. Repairing these structures may be costly and time-consuming, for this reason alternative and promising approaches like adding thermoplastic agents to thermoset matrixes emerged to extend PMCs service life. The aim of this study is to investigate poly (ethylene-co- (acrylic acid) (EAA) as a self-healing agent in carbon/epoxy composites, where damage is introduced in the material by interlaminar shear strength (ILSS) tests and hygrothermal aging. Thermoplastic pellets were ground and spread in prepregs during the fabrication of the laminate. Composite plates with 10wt % of EAA powder and no thermoplastic were investigated. Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC) were employed to evaluate materials thermal properties. Interlaminar shear strength (ILSS), Dynamic mechanical analysis (DMA), Fourier-transform infrared (FTIR) spectroscopy, and Scanning electron microscopy (SEM) were employed to investigate self-healing ability before and after the healing cycle. The addition of thermoplastic to the composite material showed recovery 9% higher of interlaminar shear strength compared to the unmodified composite. SEM images showed good adhesion between thermoplastic and epoxy resin, possible plasticisation effect due to the presence of thermoplastic, and the different healing mechanisms occurring. FTIR spectra showed evidence of good interaction between thermoplastic and epoxy resin. DMA results showed small changes in the glass transition temperature (Tg) and composite stiffness due to the addition of the thermoplastic material.

COMMITTEE MEMBERS:
Presidente - 2042234 - ANA PAULA CYSNE BARBOSA
Interno - 1202134 - JOSE DANIEL DINIZ MELO
Externo à Instituição - MARCOS YAKUTA SHIINO
Externa à Instituição - BRUNA LOUISE SILVA