Fused Filament Fabrication Three-Dimensional Printing Multi-Functional of Polylactic Acid/Carbon Black Nanocomposites

Conductive Polymer Composites (CPCs) have recently gained an extensive scientific interest as feedstock materials in Fused Filament Fabrication (FFF) Three-dimensional (3D) printing. Polylactic Acid (PLA), widely used in FFF 3D printing, as well as its Carbon Black (CB) nanocomposites at different weight percentage (wt.%) filler loadings (0.5, 1.0, 2.5 and 5.0 wt.%), were prepared via a melt mixing filament extrusion process in this study and utilized to manufacture FFF 3D printed specimens. The nanocomposites were examined for their electrical conductivity. The highest loaded 3D printed CPC (5.0 wt.%) was tested as an electrothermal Joule heating device. Static tensile, flexural, Charpy’s impact and Vickers microhardness mechanical properties were investigated for the neat and PLA/CB 3D printed nanocomposites. Dynamic Mechanical Analysis (DMA) revealed a stiffening mechanism for the PLA/CB nanocomposites. Scanning Electron Microscopy (SEM) elucidated the samples’ internal and external microstructural characteristics. The PLA/CB 5.0 wt.% nanocomposite demonstrated also antibacterial properties, when examined with a screening process, against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). It can be envisaged that the 3D printed PLA/CB CPCs exhibited a multi-functional performance, and could open new avenues towards low-cost personalized biomedical objects with complex geometry, amongst others, i.e., surgery tools, splints, wearables, etc.

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Enhanced Mechanical, Thermal and Antimicrobial Properties of Additively Manufactured Polylactic Acid with Optimized Nano Silica Content

Nanomaterials ◽

10.3390/nano11041012 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1012

Author(s):

Nectarios Vidakis ◽

Markos Petousis ◽

Emanuel Velidakis ◽

Nikolaos Mountakis ◽

Lazaros Tzounis ◽

...

Keyword(s):

Polylactic Acid ◽

Three Dimensional ◽

Antibacterial Properties ◽

Antimicrobial Properties ◽

Sio2 Nanoparticles ◽

International Standards ◽

Fused Filament Fabrication ◽

Melt Mixing ◽

Screening Process ◽

3D Printed

The scope of this work was to create, with melt mixing compounding process, novel nanocomposite filaments with enhanced properties that industry can benefit from, using commercially available materials, to enhance the performance of three-dimensional (3D) printed structures fabricated via fused filament fabrication (FFF) process. Silicon Dioxide (SiO2) nanoparticles (NPs) were selected as fillers for a polylactic acid (PLA) thermoplastic matrix at various weight % (wt.%) concentrations, namely, 0.5, 1.0, 2.0 and 4.0 wt.%. Tensile, flexural and impact test specimens were 3D printed and tested according to international standards and their Vickers microhardness was also examined. It was proven that SiO2 filler enhanced the overall strength at concentrations up to 1 wt.%, compared to pure PLA. Atomic force microscopy (AFM) was employed to investigate the produced nanocomposite extruded filaments roughness. Raman spectroscopy was performed for the 3D printed nanocomposites to verify the polymer nanocomposite structure, while thermogravimetric analysis (TGA) revealed the 3D printed samples’ thermal stability. Scanning electron microscopy (SEM) was carried out for the interlayer fusion and fractography morphological characterization of the specimens. Finally, the antibacterial properties of the produced nanocomposites were investigated with a screening process, to evaluate their performance against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus).

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Effect of Porosity and Crystallinity on 3D Printed PLA Properties

Polymers ◽

10.3390/polym11091487 ◽

2019 ◽

Vol 11 (9) ◽

pp. 1487 ◽

Cited By ~ 19

Author(s):

Yuhan Liao ◽

Chang Liu ◽

Bartolomeo Coppola ◽

Giuseppina Barra ◽

Luciano Di Maio ◽

...

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Additive Manufacturing ◽

3D Printing ◽

Polylactic Acid ◽

Complex Geometry ◽

Fused Filament Fabrication ◽

3D Printed ◽

Physical Changes ◽

Crystalline Forms

Additive manufacturing (AM) is a promising technology for the rapid tooling and fabrication of complex geometry components. Among all AM techniques, fused filament fabrication (FFF) is the most widely used technique for polymers. However, the consistency and properties control of the FFF product remains a challenging issue. This study aims to investigate physical changes during the 3D printing of polylactic acid (PLA). The correlations between the porosity, crystallinity and mechanical properties of the printed parts were studied. Moreover, the effects of the build-platform temperature were investigated. The experimental results confirmed the anisotropy of printed objects due to the occurrence of orientation phenomena during the filament deposition and the formation both of ordered and disordered crystalline forms (α and δ, respectively). A heat treatment post-3D printing was proposed as an effective method to improve mechanical properties by optimizing the crystallinity (transforming the δ form into the α one) and overcoming the anisotropy of the 3D printed object.

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Fused Filament Fabrication 3D Printed Polylactic Acid Electroosmotic Pumps

Lab on a Chip ◽

10.1039/d1lc00452b ◽

2021 ◽

Author(s):

Liang Wu ◽

Stephen Beirne ◽

Joan-Marc Cabot Canyelles ◽

Brett Paull ◽

Gordon G. Wallace ◽

...

Keyword(s):

Additive Manufacturing ◽

3D Printing ◽

Polylactic Acid ◽

Fused Filament Fabrication ◽

Flexible Approach ◽

Electroosmotic Pump ◽

3D Printed ◽

Electroosmotic Pumps

Additive manufacturing (3D printing) offers a flexible approach for the production of bespoke microfluidic structures such as the electroosmotic pump. Here a readily accessible fused filament fabrication (FFF) 3D printing...

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Three-Dimensional Printing of Hydroxyapatite Composites for Biomedical Application

Crystals ◽

10.3390/cryst11040353 ◽

2021 ◽

Vol 11 (4) ◽

pp. 353

Author(s):

Yanting Han ◽

Qianqian Wei ◽

Pengbo Chang ◽

Kehui Hu ◽

Oseweuba Valentine Okoro ◽

...

Keyword(s):

Tissue Engineering ◽

3D Printing ◽

Biomedical Application ◽

Three Dimensional ◽

Antibacterial Properties ◽

Natural Polymers ◽

Three Dimensional Printing ◽

3D Printed ◽

Dental Applications ◽

Hard Tissue Engineering

Hydroxyapatite (HA) and HA-based nanocomposites have been recognized as ideal biomaterials in hard tissue engineering because of their compositional similarity to bioapatite. However, the traditional HA-based nanocomposites fabrication techniques still limit the utilization of HA in bone, cartilage, dental, applications, and other fields. In recent years, three-dimensional (3D) printing has been shown to provide a fast, precise, controllable, and scalable fabrication approach for the synthesis of HA-based scaffolds. This review therefore explores available 3D printing technologies for the preparation of porous HA-based nanocomposites. In the present review, different 3D printed HA-based scaffolds composited with natural polymers and/or synthetic polymers are discussed. Furthermore, the desired properties of HA-based composites via 3D printing such as porosity, mechanical properties, biodegradability, and antibacterial properties are extensively explored. Lastly, the applications and the next generation of HA-based nanocomposites for tissue engineering are discussed.

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Polyamide 12/Multiwalled Carbon Nanotube and Carbon Black Nanocomposites Manufactured by 3D Printing Fused Filament Fabrication: A Comparison of the Electrical, Thermoelectric, and Mechanical Properties

C – Journal of Carbon Research ◽

10.3390/c7020038 ◽

2021 ◽

Vol 7 (2) ◽

pp. 38

Author(s):

Nectarios Vidakis ◽

Markos Petousis ◽

Lazaros Tzounis ◽

Emmanuel Velidakis ◽

Nikolaos Mountakis ◽

...

Keyword(s):

Mechanical Properties ◽

3D Printing ◽

Carbon Black ◽

Large Scale ◽

Fracture Mechanisms ◽

Fused Filament Fabrication ◽

Melt Mixing ◽

Multiwalled Carbon ◽

Electrically Conductive ◽

Polyamide 12

In this study, nanocomposites with polyamide 12 (PA12) as the polymer matrix and multiwalled carbon nanotubes (MWCNTs) and carbon black (CB) at different loadings (2.5, 5.0, and 10.0 wt.%) as fillers, were produced in 3D printing filament form by melt mixing extrusion process. The filament was then used to build specimens with the fused filament fabrication (FFF) three-dimensional (3D) printing process. The aim was to produce by FFF 3D printing, electrically conductive and thermoelectric functional specimens with enhanced mechanical properties. All nanocomposites’ samples were electrically conductive at filler loadings above the electrical percolation threshold. The highest thermoelectric performance was obtained for the PA12/CNT nanocomposite at 10.0 wt.%. The static tensile and flexural mechanical properties, as well as the Charpy’s impact and Vickers microhardness, were determined. The highest improvement in mechanical properties was observed for the PA12/CNT nanocomposites at 5.0 wt.% filler loading. The fracture mechanisms were identified by fractographic analyses of scanning electron microscopy (SEM) images acquired from fractured surfaces of tensile tested specimens. The nanocomposites produced could find a variety of applications such as; 3D-printed organic thermoelectric materials for plausible large-scale thermal energy harvesting applications, resistors for flexible circuitry, and piezoresistive sensors for strain sensing.

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Enhancement of the Compressive Strength of 3D-Printed Polylactic Acid(PLA) by Controlling Internal Pattern

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1023.75 ◽

2021 ◽

Vol 1023 ◽

pp. 75-81

Author(s):

Aappo Mustakangas ◽

Atef Hamada ◽

Antti Järvenpää

Keyword(s):

Compressive Strength ◽

3D Printing ◽

Polylactic Acid ◽

Optical Microscope ◽

Fused Filament Fabrication ◽

Loading Direction ◽

Compressive Flow ◽

3D Printed ◽

Cost Efficient ◽

Loading Axis

Cost-efficient 3D-printing can create a lot of new opportunities in engineering as it enables rapid prototyping of models and functional parts. In the present study, Polylactic acid (PLA) cubic specimens with different types of infill patterns (IPs), rectilinear, grid and cuboid, were additively manufactured by Fused Filament Fabrication 3D-printing. The PLA cubes are fabricated with one perimeter and different IPs density (10, 20, and 30%). Subsequently, the compressive strengths of the PLA materials were measured in two loading directions, i.e., the layers building direction is parallel (PD) to the loading axis and perpendicular (ND) to the loading direction. An optical microscope was used to examine the deformed IPs in both loading directions. The compressive flow stress curves of the PLA cubes infilled with rectilinear and grid patterns exhibited strong fluctuations with lower compressive strengths in the loading direction along ND. The PLA with 30% grid IP revealed a superior strength of ~12 kN in the loading direction along PD. On the contrary, the same material exhibited a worst compressive strength 3 kN along ND.

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3D-printed monolithic biofilters based on a polylactic acid (PLA) – hydroxyapatite (HAp) composite for heavy metal removal from an aqueous medium

RSC Advances ◽

10.1039/d1ra05202k ◽

2021 ◽

Vol 11 (51) ◽

pp. 32408-32418

Author(s):

Natalia Fijoł ◽

Hani Nasser Abdelhamid ◽

Binsi Pillai ◽

Stephen A. Hall ◽

Nebu Thomas ◽

...

Keyword(s):

Heavy Metal ◽

Phase Separation ◽

3D Printing ◽

Polylactic Acid ◽

Metal Removal ◽

Heavy Metal Removal ◽

Three Dimensional ◽

Thermally Induced Phase Separation ◽

Thermally Induced ◽

3D Printed

Water purification filters based on polylactic acid functionalised with hydroxyapatite were prepared by solvent-assisted blending and thermally induced phase separation (TIPS), extruded into filaments and processed via three-dimensional (3D) printing.

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Three-Dimensional Printed Antimicrobial Objects of Polylactic Acid (PLA)-Silver Nanoparticle Nanocomposite Filaments Produced by an In-Situ Reduction Reactive Melt Mixing Process

Biomimetics ◽

10.3390/biomimetics5030042 ◽

2020 ◽

Vol 5 (3) ◽

pp. 42 ◽

Cited By ~ 2

Author(s):

Nectarios Vidakis ◽

Markos Petousis ◽

Emmanouel Velidakis ◽

Marco Liebscher ◽

Lazaros Tzounis

Keyword(s):

Polylactic Acid ◽

Silver Nanoparticle ◽

Antimicrobial Properties ◽

P Value ◽

In Situ Reduction ◽

Fused Filament Fabrication ◽

Melt Mixing ◽

3D Printed ◽

Reactive Melt

In this study, an industrially scalable method is reported for the fabrication of polylactic acid (PLA)/silver nanoparticle (AgNP) nanocomposite filaments by an in-situ reduction reactive melt mixing method. The PLA/AgNP nanocomposite filaments have been produced initially reducing silver ions (Ag+) arising from silver nitrate (AgNO3) precursor mixed in the polymer melt to elemental silver (Ag0) nanoparticles, utilizing polyethylene glycol (PEG) or polyvinyl pyrrolidone (PVP), respectively, as macromolecular blend compound reducing agents. PEG and PVP were added at various concentrations, to the PLA matrix. The PLA/AgNP filaments have been used to manufacture 3D printed antimicrobial (AM) parts by Fused Filament Fabrication (FFF). The 3D printed PLA/AgNP parts exhibited significant AM properties examined by the reduction in Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) bacteria viability (%) experiments at 30, 60, and 120 min duration of contact (p < 0.05; p-value (p): probability). It could be envisaged that the 3D printed parts manufactured and tested herein mimic nature’s mechanism against bacteria and in terms of antimicrobial properties, contact angle for their anti-adhesive behavior and mechanical properties could create new avenues for the next generation of low-cost and on-demand additive manufacturing produced personal protective equipment (PPE) as well as healthcare and nosocomial antimicrobial equipment.

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Mechanical Properties of 3D-Printed Acrylonitrile–Butadiene–Styrene TiO2 and ATO Nanocomposites

Polymers ◽

10.3390/polym12071589 ◽

2020 ◽

Vol 12 (7) ◽

pp. 1589 ◽

Cited By ~ 2

Author(s):

Nectarios Vidakis ◽

Markos Petousis ◽

Athena Maniadi ◽

Emmanuel Koudoumas ◽

Marco Liebscher ◽

...

Keyword(s):

Mechanical Properties ◽

Mechanical Performance ◽

Sno2 Nanoparticles ◽

Three Dimensional ◽

Acrylonitrile Butadiene Styrene ◽

International Standards ◽

Fused Filament Fabrication ◽

Melt Mixing ◽

3D Printed ◽

Butadiene Styrene

In order to enhance the mechanical performance of three-dimensional (3D) printed structures fabricated via commercially available fused filament fabrication (FFF) 3D printers, novel nanocomposite filaments were produced herein following a melt mixing process, and further 3D printed and characterized. Titanium Dioxide (TiO2) and Antimony (Sb) doped Tin Oxide (SnO2) nanoparticles (NPs), hereafter denoted as ATO, were selected as fillers for a polymeric acrylonitrile butadiene styrene (ABS) thermoplastic matrix at various weight % (wt%) concentrations. Tensile and flexural test specimens were 3D printed, according to international standards. It was proven that TiO2 filler enhanced the overall tensile strength by 7%, the flexure strength by 12%, and the micro-hardness by 6%, while for the ATO filler, the corresponding values were 9%, 13%, and 6% respectively, compared to unfilled ABS. Atomic force microscopy (AFM) revealed the size of TiO2 (40 ± 10 nm) and ATO (52 ± 11 nm) NPs. Raman spectroscopy was performed for the TiO2 and ATO NPs as well as for the 3D printed nanocomposites to verify the polymer structure and the incorporated TiO2 and ATO nanocrystallites in the polymer matrix. The scope of this work was to fabricate novel nanocomposite filaments using commercially available materials with enhanced overall mechanical properties that industry can benefit from.

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Extrusion-Based 3D Printing for Highly Porous Alginate Materials Production

Gels ◽

10.3390/gels7030092 ◽

2021 ◽

Vol 7 (3) ◽

pp. 92

Author(s):

Natalia Menshutina ◽

Andrey Abramov ◽

Pavel Tsygankov ◽

Daria Lovskaya

Keyword(s):

3D Printing ◽

Sodium Alginate ◽

Complex Geometry ◽

Three Dimensional ◽

Supercritical Drying ◽

High Specific Surface Area ◽

Wide Range ◽

Potential Applications ◽

3D Printed ◽

Highly Porous

Three-dimensional (3D) printing is a promising technology for solving a wide range of problems: regenerative medicine, tissue engineering, chemistry, etc. One of the potential applications of additive technologies is the production of highly porous structures with complex geometries, while printing is carried out using gel-like materials. However, the implementation of precise gel printing is a difficult task due to the high requirements for “ink”. In this paper, we propose the use of gel-like materials based on sodium alginate as “ink” for the implementation of the developed technology of extrusion-based 3D printing. Rheological studies were carried out for the developed alginate ink compositions. The optimal rheological properties are gel-like materials based on 2 wt% sodium alginate and 0.2 wt% calcium chloride. The 3D-printed structures with complex geometry were successfully dried using supercritical drying. The resulting aerogels have a high specific surface area (from 350 to 422 m2/g) and a high pore volume (from 3 to 3.78 cm3/g).

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