Functional post-processing of extrusion-based 3D printed parts: polyaniline (PAni) as a coating for thermoplastics components

• Type: Article in International Scientific Journal
• Date: 2024

Authors

Cruzeiro, AD (Author) Other; Santana, L (Author) Other; Jaime, DM (Author) Other; Ramoa, S (Author) Other; Jorge Lino (Author) FEUP; Barra, GMD (Author) Other

Journal

Title: Rapid Prototyping Journal

Vol. 30 No. 11

Pages: 1517-1536

ISSN: 1355-2546

Publisher: Emerald

Indexing

ISI Web of Knowledge - 0 Citations

Scopus - 0 Citations

Other information

Authenticus ID: P-012-NJH

DOI: 10.1108/rpj-11-2023-0413

Abstract (EN): Purpose - This study aims to evaluate in situ oxidative polymerization of aniline (Ani) as a post-processing method to promote extrusion-based 3D printed parts, made from insulating polymers, to components with functional properties, including electrical conductivity and chemical sensitivity. Design/methodology/approach - Extrusion-based 3D printed parts of polyethylene terephthalate modified with glycol (PETG) and polypropylene (PP) were coated in an aqueous acid solution via in situ oxidative polymerization of Ani. First, the feedstocks were characterized. Densely printed samples were then used to assess the adhesion of polyaniline (PAni) and electrical conductivity on printed parts. The best feedstock candidate for PAni coating was selected for further analysis. Last, a Taguchi methodology was used to evaluate the influence of printing parameters on the coating of porous samples. Analysis of variance and Tukey post hoc test were used to identify the best levels for each parameter. Findings - Colorimetry measurements showed significant color shifts in PP samples and no shifts in PETG samples upon pullout testing. The incorporation of PAni content and electrical conductivity were, respectively, 41% and 571% higher for PETG in comparison to PP. Upon coating, the surface energy of both materials decreased. Additionally, the dynamic mechanical analysis test showed minimal influence of PAni over the dynamic mechanical properties of PETG. The parametric study indicated that only layer thickness and infill pattern had a significant influence on PAni incorporation and electrical conductivity of coated porous samples. Originality/value - Current literature reports difficulties in incorporating PAni without affecting dimensional precision and feedstock stability. In situ, oxidative polymerization of Ani could overcome these limitations. However, its use as a functional post-processing of extrusion-based printed parts is a novelty.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 20