Banca de DEFESA: ISAAC DE SANTANA BEZERRA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : ISAAC DE SANTANA BEZERRA
DATE: 18/08/2023
TIME: 14:00
LOCAL: meet.google.com/bwd-raup-irj
TITLE:

Analysis of production of porous scaffolds by 3D printing

KEY WORDS:

3D Printing, Scaffolds, PLA, AZDA

PAGES: 80
BIG AREA: Engenharias
AREA: Engenharia de Materiais e Metalúrgica
SUBÁREA: Materiais Não-Metálicos
SPECIALTY: Polímeros, Aplicações
SUMMARY:

This work analyzed the feasibility of producing porous scaffolds by 3D printing (IMP3D) via melt-deposition modeling (FDM) of Poly(lactic acid) (PLA) with azodicarbonamide (AZDA) blowing agent. A selection of the polymer matrix was carried out based on mechanical, rheological and morphological tests, comparing Poly(acrylonitrile-co-butadiene-co-styrene) (ABS), Poly(ethylene terephthalate) bottle grade (PETG) and PLA, both by means of injection molding, as well as by IMP3D, using nozzles with diameters of 0.3; 0.4; 0.5; 0.6; 0.8; 1.0. After weighing the productive efficiency, the processability, and the mechanical results obtained, IMP3D and PLA were selected as the most suitable technique and material for the production of porous scaffolds. Subsequently, the PLA was subjected to a closed cycle of five consecutive processes in a twin screw extruder, verifying by the visual and rheological changes, that the material maintained good rheological properties after the thermal cycles. Finally, the PLA was mixed with the expanding agent azodicarbonamide (AZDA) in a twin-screw extruder, and plasticized in a single-screw extruder, obtaining PLA filaments with inert AZDA, for subsequent printing of porous scaffolds, in proportions in percentages per hundred resin (PCR) of: 100/0; 100/2; 100/4; 100/6; 100/8. The rheological, morphological and uniaxial traction characterizations of the developed materials were carried out, noting the increase in PLA viscosity when subjected to more thermal cycles. The morphologies pointed to a greater emergence of pores for the compositions with higher concentration of AZDA, so that the larger pores were preferentially present in the central regions of the filaments, in addition to showing that the temperature control influences the size of the pores obtained, reaching biodegradable and biocompatible porous structures.

COMMITTEE MEMBERS:
Presidente - 1639676 - EDSON NORIYUKI ITO
Externa ao Programa - 1989838 - CAROLINE DANTAS VILAR - UFRNExterno à Instituição - ERIK DOS SANTOS SILVA - UNIFEI
Externo à Instituição - FELIPE PEDRO DA COSTA GOMES - UFPE