Biocidal and reinforced PETG/antibacterial blend nanocomposite for extrusion-based additive manufacturing: Optimization course and printability scores

Polyethylene terephthalate glycol (PETG) is an amorphous polymer that has been widely used in numerous applications, from everyday life to medical and even defense-related applications. The latter constitute very demanding environments in which, in many cases, specific multifunctionalities are required. Herein, we aim for specific functionalities to appear simultaneously, thus creating novel materials that can provide important solutions to applications. Therefore, inducing antibacterial properties along with enhanced mechanical properties for use in the defense and security domains constitutes an additional asset when disease spread becomes very important. To address this challenge, we mixed pure PETG with an antibacterial nanopowder to investigate these novel multifunctionalities in detail. Concomitantly, the enhancement of the mechanical properties of the 3D printed PETG/antibacterial nanocomposites was thoroughly examined. Several PETG nanocomposites were manufactured with different nanopowder loadings and turned into filaments for use in the AM method of material extrusion (MEX). The several 3D printed PETG/antibacterial nanocomposites were thoroughly investigated for their mechanical and rheological properties, thermal stability, and morphological, structural, and chemical characteristics, combined with antibacterial performance, against two common pathogens, s. aureus and e. coli, using the agar well diffusion method. The outcome of the nanopowder introduction to the quality metrics of the 3D printed PETG, namely the geometrical accuracy and pores of the 3D printed structure was also investigated through high-resolution micro-computed tomography. The PETG/antibacterial nanocomposites exhibited improved mechanical properties. A 13.6 % tensile strength increase was achieved with 8 wt% content. 10 wt % achieved 17 % Young's modulus increase, 19 % flexural strength and 18.2 % flexural modulus improvement and can be considered the optimum loading of the research. Nanocompounds also showed strong antibacterial activity against s. aureus and E. coli. These induced multifunctionalities can constitute a new class of materials where the desired properties can have significant applications in two or more different fields for functional, durable, and infection-resistant materials, such as in the demanding defense and security sector, the medical field, or both.