Antibacterial silver submicron wire-polylactic acid composites for fused filament fabrication
ISSN: 1355-2546
Article publication date: 2 September 2019
Issue publication date: 8 January 2020
Abstract
Purpose
The purpose of this study is to explore the use of silver submicron-scale wire (AgSMW) additives in filament feedstock for fused filament fabrication (FFF) additive manufacturing technologies. The antibacterial effect of the additive on printed objects is assessed and its impact on mechanical behavior is determined.
Design/methodology/approach
AgSMW-PLA composite FFF filaments were fabricated by solution processing, granulation and extrusion. The reduction in the growth of Escherichia coli (E. coli) is measured after exposure to FFF-printed composite test specimens with AgSMW additive concentrations ranging from 0.0 to 10.0 weight per cent. The effect of the additive addition on the thermal properties and tensile mechanical performance was measured. Scanning electron microscopy (SEM) was used to analyze the composite microstructure and fracture behavior.
Findings
E. coli growth was reduced by approximately 50 per cent at the highest additive concentration of 10.0 weight per cent. This is attributed to the release of silver ions through water diffusion into the bulk of the composite. The ultimate tensile strength declined with increasing AgSMW concentration with a moderate reduction of 18 per cent at 10.0 weight per cent. The elastic modulus did not vary significantly at any of the concentrations studied. The ductility of the composite was only notably reduced at the highest concentration. The reduction in mechanical strength and strain at break is attributed to an increase in void defects in the composite with increasing additive concentration.
Originality/value
This study demonstrates the successful incorporation of AgSMWs into FFF-compatible filaments for use in commercially available printing systems. The results demonstrate significant reduction of bacteria growth when using these materials. While the mechanical performance degrades slightly, the results indicate the material’s efficacy for a variety of potential biomedical applications. As a proof of concept, surgical tools were printed using the composite.
Keywords
Acknowledgements
This work was supported through funding from the University of New Orleans (UNO) Office of Research Stimulating Competitive Research (SCoRe) program and the Louisiana Board of Regents Research Competitiveness Subprogram (RCS). The authors would also like to thank Dr Wendy Schluchter from the UNO biology department and Dr. Jibao He from the Tulane University CIF microscopy lab for the use of their facilities.
Citation
Walker, J.S., Arnold, J., Shrestha, C. and Smith, D. (2020), "Antibacterial silver submicron wire-polylactic acid composites for fused filament fabrication", Rapid Prototyping Journal, Vol. 26 No. 1, pp. 32-38. https://doi.org/10.1108/RPJ-04-2019-0100
Publisher
:Emerald Publishing Limited
Copyright © 2019, Emerald Publishing Limited