scholarly journals Effects of Filament Extrusion, 3D Printing and Hot-Pressing on Electrical and Tensile Properties of Poly(Lactic) Acid Composites Filled with Carbon Nanotubes and Graphene

Nanomaterials ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 35 ◽  
Author(s):  
Giovanni Spinelli ◽  
Rumiana Kotsilkova ◽  
Evgeni Ivanov ◽  
Ivanka Petrova-Doycheva ◽  
Dzhihan Menseidov ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Electrical Conductivity ◽  
Lactic Acid ◽  
3D Printing ◽  
Tensile Properties ◽  
Hot Pressing ◽  
Multiwall Carbon Nanotubes ◽  
Poly Lactic Acid ◽  
The Matrix ◽  
3D Printed

In this study, the effects of three processing stages: filament extrusion, 3D printing (FDM), and hot-pressing are investigated on electrical conductivity and tensile mechanical properties of poly(lactic) acid (PLA) composites filled with 6 wt.% of multiwall carbon nanotubes(MWCNTs), graphene nanoplatelets (GNPs), and combined fillers. The filaments show several decades’ higher electrical conductivity and 50–150% higher values of tensile characteristics, compared to the 3D printed and the hot-pressed samples due to the preferential orientation of nanoparticles during filament extrusion. Similar tensile properties and slightly higher electrical conductivity are found for the hot-pressed compared to the 3D printed samples, due to the reduction of interparticle distances, and consequently, the reduced tunneling resistances in the percolated network by hot pressing. Three structural types are observed in nanocomposite filaments depending on the distribution and interactions of fillers, such as segregated network, homogeneous network, and aggregated structure. The type of structural organization of MWCNTs, GNPs, and combined fillers in the matrix polymer is found determinant for the electrical and tensile properties. The crystallinity of the 3D printed samples is higher compared to the filament and hot-pressed samples, but this structural feature has a slight effect on the electrical and tensile properties. The results help in understanding the influence of processing on the properties of the final products based on PLA composites.

scholarly journals Stress, strain and deformation of poly-lactic acid filament deposited onto polyethylene terephthalate woven fabric through 3D printing process

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Prisca Aude Eutionnat-Diffo ◽  
Yan Chen ◽  
Jinping Guan ◽  
Aurelie Cayla ◽  
Christine Campagne ◽  
...  
Keyword(s):  
Lactic Acid ◽  
3D Printing ◽  
Tensile Properties ◽  
Polyethylene Terephthalate ◽  
Polymeric Materials ◽  
Deposition Process ◽  
Woven Fabric ◽  
Poly Lactic Acid ◽  
Printing Process ◽  
3D Printed

Abstract Although direct deposition of polymeric materials onto textiles through 3D printing is a great technique used more and more to develop smart textiles, one of the main challenges is to demonstrate equal or better mechanical resistance, durability and comfort than those of the textile substrates before deposition process. This article focuses on studying the impact of the textile properties and printing platform temperature on the tensile and deformations of non-conductive and conductive poly lactic acid (PLA) filaments deposited onto polyethylene terephthalate (PET) textiles through 3D printing process and optimizing them using theoretical and statistical models. The results demonstrate that the deposition process affects the tensile properties of the printed textile in comparison with the ones of the textiles. The stress and strain at rupture of the first 3D printed PLA layer deposited onto PET textile material reveal to be a combination of those of the printed layer and the PET fabric due to the lower flexibility and diffusion of the polymeric printed track through the textile fabric leading to a weak adhesion at the polymer/textile interface. Besides, printing platform temperature and textile properties influence the tensile and deformation properties of the 3D printed PLA on PET textile significantly. Both, the washing process and the incorporation of conductive fillers into the PLA do not affect the tensile properties of the extruded polymeric materials. The elastic, total and permanent deformations of the 3D-printed PLA on PET fabrics are lower than the ones of the fabric before polymer deposition which demonstrates a better dimensional stability, higher stiffness and lower flexibility of these materials.

scholarly journals Study of the Wear Resistance of Conductive Poly Lactic Acid Monofilament 3D Printed onto Polyethylene Terephthalate Woven Materials

Materials ◽  
2020 ◽  
Vol 13 (10) ◽  
pp. 2334
Author(s):  
Prisca Aude Eutionnat-Diffo ◽  
Yan Chen ◽  
Jinping Guan ◽  
Aurelie Cayla ◽  
Christine Campagne ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Weight Loss ◽  
Wear Resistance ◽  
Lactic Acid ◽  
3D Printing ◽  
Fused Deposition Modeling ◽  
Poly Lactic Acid ◽  
Fused Deposition ◽  
Deposition Modeling ◽  
3D Printed

Wear resistance of conductive Poly Lactic Acid monofilament 3D printed onto textiles, through Fused Deposition Modeling (FDM) process and their electrical conductivity after abrasion are important to consider in the development of smart textiles with preserved mechanical and electrical properties. The study aims at investigating the weight loss after abrasion and end point of such materials, understanding the influence of the textile properties and 3D printing process parameters and studying the impact of the abrasion process on the electrical conductivity property of the 3D printed conductive polymers onto textiles. The effects of the 3D printing process and the printing parameters on the structural properties of textiles, such as the thickness of the conductive Poly Lactic Acid (PLA) 3D printed onto polyethylene terephthalate (PET) textile and the average pore sizes of its surface are also investigated. Findings demonstrate that the textile properties, such as the pattern and the process settings, for instance, the printing bed temperature, impact significantly the abrasion resistance of 3D printed conductive Poly Lactic Acid (PLA) onto PET woven textiles. Due to the higher capacity of the surface structure and stronger fiber-to-fiber cohesion, the 3D printed conductive polymer deposited onto textiles through Fused Deposition Modeling process have a higher abrasion resistance and lower weight loss after abrasion compared to the original fabrics. After printing the mean pore size, localized at the surface of the 3D-printed PLA onto PET textiles, is five to eight times smaller than the one of the pores localized at the surface of the PET fabrics prior to 3D printing. Finally, the abrasion process did considerably impact the electrical conductivity of 3D printed conductive PLA onto PET fabric.

scholarly journals Nanoindentation analysis of 3D printed poly(lactic acid)-based composites reinforced with graphene and multiwall carbon nanotubes

2018 ◽  
Vol 136 (13) ◽  
pp. 47260 ◽  
Author(s):  
Todor Batakliev ◽  
Vladimir Georgiev ◽  
Evgeni Ivanov ◽  
Rumiana Kotsilkova ◽  
Rosa Di Maio ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Lactic Acid ◽  
Multiwall Carbon Nanotubes ◽  
Poly Lactic Acid ◽  
3D Printed ◽  
Multiwall Carbon

3D Printing of Flexible and Stretchable Parts Using Multiwall Carbon Nanotubes/Polyester-Based Thermoplastic Polyurethane

2020 ◽  
Author(s):  
Felicia Stan ◽  
Nicoleta-Violeta Stanciu ◽  
Adriana-Madalina Constantinescu ◽  
Catalin Fetecau
Keyword(s):  
Carbon Nanotubes ◽  
Electrical Conductivity ◽  
3D Printing ◽  
Thermoplastic Polyurethane ◽  
Multiwall Carbon Nanotubes ◽  
Gauge Factor ◽  
3D Printed ◽  
The Stability ◽  
Printing Direction ◽  
Multiwall Carbon

Abstract This paper reports on the 3D printing of flexible and stretchable parts based on multiwall carbon nanotubes (MWCNTs)/polyester-based thermoplastic polyurethane (TPU) nanocomposites. The rheological properties of the MWCNT/TPU nanocomposites with different wt.% of MWCNTs (0.1–3) were determined and used as guidance for the extrusion and 3D printing processes. MWCNT/TPU filaments were extruded and used for 3D printing of different flexible and stretchable parts. The mechanical, electrical, and piezoresistive response of the MWCNT/TPU nanocomposite filaments and 3D printed parts under static and monotonic loading was studied. The experimental results show that with increasing temperature and shear rate, respectively, the shear viscosity of the MWCNT/TPU nanocomposite decreases, whereas the viscosity increases with increasing wt.% of MWCNTs. With the addition of MWCNTs, the elastic modulus and tensile strength of the feedstock filament all increase, enhancing the printability of TPU by increasing the buckling resistance and the stability of the 3D printed layer. The electrical conductivity of the 3D printed MWCNT/TPU nanocomposites increases with increasing wt.% of MWCNTs and exceeds the conductivity of the filaments. The 3D printed MWCNT/TPU nanocomposites with 3 wt.% show an electrical conductivity about 10 S/m, irrespective of the printing direction. Moreover, the 3D printed MWCNT/TPU nanocomposites exhibit good mechanical properties and high piezoresistive sensitivity with gauge factor (50–600) dependent on both strain and printing direction.

scholarly journals Release of Graphene and Carbon Nanotubes from Biodegradable Poly(Lactic Acid) Films during Degradation and Combustion: Risk Associated with the End-of-Life of Nanocomposite Food Packaging Materials

Materials ◽  
2018 ◽  
Vol 11 (12) ◽  
pp. 2346 ◽  
Author(s):  
Stanislav Kotsilkov ◽  
Evgeni Ivanov ◽  
Nikolay Vitanov
Keyword(s):  
Risk Assessment ◽  
Carbon Nanotubes ◽  
Lactic Acid ◽  
Food Packaging ◽  
Safety Concern ◽  
Barrier Properties ◽  
Nanocomposite Films ◽  
Poly Lactic Acid ◽  
Qualitative Risk Assessment ◽  
The Matrix

Nanoparticles of graphene and carbon nanotubes are attractive materials for the improvement of mechanical and barrier properties and for the functionality of biodegradable polymers for packaging applications. However, the increase of the manufacture and consumption increases the probability of exposure of humans and the environment to such nanomaterials; this brings up questions about the risks of nanomaterials, since they can be toxic. For a risk assessment, it is crucial to know whether airborne nanoparticles of graphene and carbon nanotubes can be released from nanocomposites into the environment at their end-life, or whether they remain embedded in the matrix. In this work, the release of graphene and carbon nanotubes from the poly(lactic) acid nanocomposite films were studied for the scenarios of: (i) biodegradation of the matrix polymer at the disposal of wastes; and (ii) combustion and fire of nanocomposite wastes. Thermogravimetric analysis in air atmosphere, transmission electron microscopy (TEM), atomic force microscopy (AFM) and scanning electron microscope (SEM) were used to verify the release of nanoparticles from nanocomposite films. The three factors model was applied for the quantitative and qualitative risk assessment of the release of graphene and carbon nanotubes from nanocomposite wastes for these scenarios. Safety concern is discussed in respect to the existing regulations for nanowaste stream.

scholarly journals Essential Nanostructure Parameters to Govern Reinforcement and Functionality of Poly(lactic) Acid Nanocomposites with Graphene and Carbon Nanotubes for 3D Printing Application

Polymers ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1208 ◽  
Author(s):  
Rumiana Kotsilkova ◽  
Evgeni Ivanov ◽  
Vladimir Georgiev ◽  
Radost Ivanova ◽  
Dzhihan Menseidov ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Lactic Acid ◽  
3D Printing ◽  
Percolation Threshold ◽  
Structural Parameters ◽  
Electromagnetic Properties ◽  
Rheological Parameters ◽  
Poly Lactic Acid ◽  
Structure Property ◽  
Degree Of Dispersion

Poly(lactic) acid nanocomposites filled with graphene nanoplatelets (GNPs) and multiwall carbon nanotubes (MWCNTs) are studied, varying the filler size, shape, and content within 1.5–12 wt.%. The effects of the intrinsic characteristics of nanofillers and structural organization of nanocomposites on mechanical, electrical, thermal, and electromagnetic properties enhancement are investigated. Three essential rheological parameters are identified, which determine rheology–structure–property relations in nanocomposites: the degree of dispersion, percolation threshold, and interfacial interactions. Above the percolation threshold, depending on the degree of dispersion, three structural organizations are observed in nanocomposites: homogeneous network (MWCNTs), segregated network (MWCNTs), and aggregated structure (GNPs). The rheological and structural parameters depend strongly on the type, size, shape, specific surface area, and functionalization of the fillers. Consequently, the homogeneous and segregated network structures resulted in a significant enhancement of tensile mechanical properties and a very low electrical percolation threshold, in contrast to the aggregated structure. The high filler density in the polymer and the low number of graphite walls in MWCNTs are found to be determinant for the remarkable shielding efficiency (close to 100%) of nanocomposites. Moreover, the 2D shaped GNPs predominantly enhance the thermal conductivity compared to the 1D shaped MWCNTs. The proposed essential structural parameters may be successfully used for the design of polymer nanocomposites with enhanced multifunctional properties for 3D printing applications.

scholarly journals Effects of wood flour and MA-EPDM on the properties of fused deposition modeling 3D-printed poly lactic acid composites

BioResources ◽  
2021 ◽  
Vol 16 (4) ◽  
pp. 7122-7138
Author(s):  
Sang-U Bae ◽  
Young-Rok Seo ◽  
Birm-June Kim ◽  
Min Lee
Keyword(s):  
Lactic Acid ◽  
3D Printing ◽  
Fused Deposition Modeling ◽  
Wood Flour ◽  
Poly Lactic Acid ◽  
Common System ◽  
Fused Deposition ◽  
Deposition Modeling ◽  
3D Printed ◽  
Material Composite

Fused deposition modeling (FDM) 3D printing technology is the most common system for polymer additive manufacturing (AM). Recent studies have been conducted to expand both the range of materials that can be used for FDM and their applications. As a filler, wood flour was incorporated into poly lactic acid (PLA) polymer to develop a biocomposite material. Composite filaments were manufactured with various wood flour contents and then successfully used for 3D printing. Morphological, mechanical, and biodegradation properties of FDM 3D-printed PLA composites were investigated. To mitigate brittleness, 5 phr of maleic anhydride grafted ethylene propylene diene monomer (MA-EPDM) was added to the composite blends, and microstructural properties of the composites were examined by scanning electron microscopy (SEM). Mechanical strength tests demonstrated that elasticity was imparted to the composites. Additionally, test results showed that the addition of wood flour to the PLA matrix promoted pore generation and further influenced the mechanical and biodegradation properties of the 3D-printed composites. An excellent effect of wood flour on the biodegradation properties of FDM 3D-printed PLA composites was observed.

scholarly journals Tensile Properties of Poly Lactic Acid (PLA)–Tungsten Trioxide (WO3) Nano Composites for 3D Printing Process

2019 ◽  
Vol 9 (1) ◽  
pp. 2511-2513
Keyword(s):  
Lactic Acid ◽  
3D Printing ◽  
Tensile Properties ◽  
Tungsten Trioxide ◽  
Control Sample ◽  
Industrial Applications ◽  
Poly Lactic Acid ◽  
Nano Composites ◽  
Aliphatic Polyesters ◽  
Printing Process

Poly Lactic Acid (PLA) is one of the most crucial aliphatic polyesters which is considered as one of the favourable options in environmentally friendly thermoplastic polymers since it could be biodegraded in certain conditions. PLA has been extensively used in the packaging, electronic industries, and household applications. As a result, the improvement of mechanical properties of PLA is necessary, which can be achieved through heat resistant materials such as Tungsten trioxide (WO3 ). The objective of this research was to investigate the tensile properties of PLA-WO3 . The 3D printing process was employed to fabricate PLA-WO3 (3wt% WO3 ) and Neat PLA (control sample). The tensile test was conducted to investigate the effect of WO3 to the PLA. The results show that the tensile properties of PLA-WO3 were improved up to 75% as compared to Neat PLA. This result shows positive indication to the PLA-WO3 for many industrial applications.

scholarly journals Effects of Graphene Nanoplatelets and Multiwall Carbon Nanotubes on the Structure and Mechanical Properties of Poly(lactic acid) Composites: A Comparative Study

2019 ◽  
Vol 9 (3) ◽  
pp. 469 ◽  
Author(s):  
Todor Batakliev ◽  
Ivanka Petrova-Doycheva ◽  
Verislav Angelov ◽  
Vladimir Georgiev ◽  
Evgeni Ivanov ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Carbon Nanotubes ◽  
Lactic Acid ◽  
Low Cost ◽  
Multiwall Carbon Nanotubes ◽  
Poly Lactic Acid ◽  
Carbon Filler ◽  
Multi Walled Carbon Nanotubes ◽  
Carbon Fillers ◽  
Walled Carbon Nanotubes

Poly(lactic acid)/graphene and poly(lactic acid)/carbon nanotube nanocomposites were prepared by an easy and low-cost method of melt blending of preliminary grinded poly(lactic acid) (PLA) with nanosized carbon fillers used as powder. Morphological, structural and mechanical properties were investigated to reveal the influence of carbon nanofiller on the PLA–based composite. The dependence of tensile strength on nanocomposite loading was defined by a series of experiments over extruded filaments using a universal mechanical testing instrument. The applying the XRD technique disclosed that compounds crystallinity significantly changed upon addition of multi walled carbon nanotubes. We demonstrated that Raman spectroscopy can be used as a quick and unambiguous method to determine the homogeneity of the nanocomposites in terms of carbon filler dispersion in a polymer matrix.

Sign in / Sign up

Export Citation Format

Share Document