Banca de DEFESA: ALINE TIEMI SUGANO SEGURA RAMOS

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : ALINE TIEMI SUGANO SEGURA RAMOS
DATE: 25/11/2022
TIME: 14:00
LOCAL: Online
TITLE:

Effects of the addition of microfibrillated (CMF) and nanofibrillated (CNF) celullose on the properties of water-dispersed TPU adhesives

PAGES: 120
BIG AREA: Engenharias
AREA: Engenharia de Materiais e Metalúrgica
SUBÁREA: Materiais Não-Metálicos
SPECIALTY: Polímeros, Aplicações
SUMMARY:

The search for less polluting alternatives to the organic solvents present in polyurethane (PU) adhesives promoted the use of aqueous dispersions of this polymer.  However, the main challenge to develop water-dispersed PU adhesives is to maintain the thermal, mechanical, rheological and adhesive properties similar to the ones obtained by solvent-based adhesives, like toluene and hexane. A possible way to maintain these properties is to add reinforcements, chiefly nano-reinforcements. In this work, fibrillated cellulose (FC) was added to these adhesives in the attempt to improve their properties, hence, the objective of this study is to demonstrate that the incorporation of FC (microfibrillated and nanofibrillated) increases the mechanical strength of the adhesive film and the adhesive power of the composites formed when compared to pure PU and to verify the relation between the degree of CF defibrillation with its efficiency in reinforcing aqueous PU adhesives. The matrix used is an aqueous dispersion of thermoplastic polyurethane (TPU), and the reinforcement is CF with different degrees of defibrillation. The CFs were incorporated to the TPU dispersion, at concentrations of 1 wt%, 2 wt% and 3 wt%. The characterization of CF was performed by SEM, FTIR, and TGA tests. The matrix and composites crystallization kinetics were evaluated by differential scanning calorimetry (DSC). To evaluate the adhesive’s cohesion and adherence the produced films were tested by dynamic-mechanical analysis (DMA) and by T-peel test. The characterization of CF showed the differences of morphology, thermal stability, and composition of the fibers and helped evaluate the quality of the composites produced with them. Composite evaluation showed that the CF has the potential to be used as reinforcement for the TPU adhesive.

BANKING MEMBERS:
Presidente - Interno ao Programa - 1761120 - DANILO JUSTINO CARASTAN
Membro Titular - Examinador(a) Interno ao Programa - 1671298 - RENATO ALTOBELLI ANTUNES
Membro Titular - Examinador(a) Externo ao Programa - 1730526 - SUEL ERIC VIDOTTI
Membro Titular - Examinador(a) Externo à Instituição - ADRIANA MARTINELLI CATELLI DE SOUZA - FEI
Membro Titular - Examinador(a) Externo à Instituição - ROGERIO RAMOS DE SOUSA JUNIOR - UFABC
Membro Suplente - Examinador(a) Interno ao Programa - 1734908 - FABIO FURLAN FERREIRA
Membro Suplente - Examinador(a) Interno ao Programa - 1676364 - JULIANA MARCHI
Membro Suplente - Examinador(a) Externo à Instituição - BALTUS CORNELIUS BONSE - FEI
Membro Suplente - Examinador(a) Externo à Instituição - ANA PAULA LEMES