Scaffold de alumina obtido por fabricação por filamento fundido

Abstract

Tissue engineering aims to replace the affected tissues and organs through structures known as scaffolds. Biomaterials and tissue engineering can be applied in tissue replacement, through the use of biocompatible, bioactive and biodegradable materials, manufactured in different configurations. Not only in health but also in the petrochemical industry, porous ceramics are widely used for improving catalytic efficiency, for the ability to mimic the porosity of natural systems, in addition to providing adequate surface area, among other advantages. Thus, it is necessary to produce complex porous structures with controlled porosity, which can be done by additive manufacturing, as it is a fast method and allows the obtaining of highly complex parts. Additive manufacturing (AM), also known as 3D printing, has been one of the most used tools due to its ability to manufacture metallic, polymeric, ceramic, and composite material structures with a high complexity of shapes. To obtain a three-dimensional structure, for application in health and in the chemical industry, in this work, alumina scaffolds with LDPE, alumina with ABS, and alumina with PLA were produced by fused filament fabrication (FFF). The extrusion process was used to obtain the printing wire. The wire is composed of a mixture of polymer and ceramic (with and without stearic acid) and then used to print the scaffolds. The micrographs of the filaments allowed us to identify that the presence of stearic acid, in the amount of 9.0% by weight, allowed more significant interaction of the polymer with the ceramic particles and reduced the viscosity of the mixture. The 3D printing stage of the filaments was possible to be carried out with all mixtures. The process of extracting the organic vehicle (debinding) from mixtures with LDPE, ABS, and PLA was satisfactory, with ideal compaction characteristics, good interaction between the deposited layers, presenting a resistant structure even with high porosity, without the presence of defects. However, it must be taken into account that the mixture with ABS showed better performance properties in all stages of the work performed, without the presence of defects, with ease of printing process, pre-sintering with resistance in the structure, and a satisfactory microporous microstructure. Being a low-cost and little-used polymer, LDPE presented difficulty in extruding filament and printing, but it presented a high porosity according to studies already carried out for biomedical applications. To obtain scaffolds, it is necessary to obey the process steps so that the final consolidation of the ceramic piece can be obtained. It is necessary to point out that for future studies, a biological analysis is necessary to obtain results of porosity efficiency for cell growth and catalytic application. The optimization of factors such as additives, temperatures used, and dwell times at these temperatures allows the obtaining of increasingly resistant parts, with properties suitable for each application. [resumo fornecido pelo autor]