The Influence of Carbon Nanotubes and Reprocessing on the Morphology and Properties of High-Density Polyethylene/Carbon Nanotube Composites

2021 ◽  
pp. 1-31
Author(s):  
Felicia Stan ◽  
Ionut-Laurentiu Sandu ◽  
Adriana-Madalina Constantinescu ◽  
Nicoleta-Violeta Stanciu ◽  
Catalin Fetecau
Keyword(s):  
Carbon Nanotubes ◽  
Carbon Nanotube ◽  
Electrical Properties ◽  
Injection Molding ◽  
High Density Polyethylene ◽  
High Density ◽  
Mechanical Degradation ◽  
End User ◽  
Mechanical Recycling ◽  
Mechanical And Electrical Properties

Abstract This study investigates virgin and recycled high-density polyethylene/multi-walled carbon nanotube (HDPE/MWCNT) composites using thermo-physical and mechanical characterization techniques to generate knowledge and understand recyclability of these composites. Firstly, virgin samples with 0.1–5 wt.% of MWCNTs were prepared by injection molding. Then, the HDPE/MWCNT composite waste was mechanically recycled and consecutively reprocessed by injection molding. The experimental results show that the degradation process of the end-user properties (mechanical and electrical properties) depends on the MWCNT wt.%. The higher the carbon nanotube loading, the higher the degradation of the end-user properties. The HDPE/MWCNT composites appear to be resistant to degradation at carbon nanotube loadings below the percolation threshold (which is located around 3 wt.%). In contrast, the recycled HDPE/MWCNT composites with 5 wt.% showed a reduction in viscosity, mechanical and electrical properties with recycling. After four reprocessing cycles, degradation in the Young modulus (−35%), tensile strength (−25%), elongation at break (−60%) and electrical conductivity (−2 orders of magnitude) of the HDPE/MWCNT composite with 5 wt.% was observed as compared with the virgin composite. From an industrial perspective, it is feasible to recycle HDPE/MWCNT composite waste by mechanical recycling and use it to manufacture products with favorable mechanical properties, covering insulating, antistatic and semiconducting ranges depending on the MWCNT loading, owing to the protective effect of carbon nanotubes against thermo-mechanical degradation.

The Influence of Carbon Nanotubes and Reprocessing on the Morphology and Properties of High-Density Polyethylene/Carbon Nanotube Composites

2021 ◽  
Author(s):  
Felicia Stan ◽  
Ionut-Laurentiu Sandu ◽  
Adriana-Madalina Turcanu ◽  
Nicoleta-Violeta Stanciu ◽  
Catalin Fetecau
Keyword(s):  
Carbon Nanotubes ◽  
Carbon Nanotube ◽  
Electrical Properties ◽  
Injection Molding ◽  
High Density Polyethylene ◽  
Young Modulus ◽  
High Density ◽  
Mechanical Recycling ◽  
Mechanical And Electrical Properties ◽  
Nanotube Composites

Abstract This study investigates virgin and recycled high-density polyethylene/multi-walled carbon nanotube (HDPE/MWCNT) composites using thermo-physical and mechanical characterization techniques to generate knowledge and understand recyclability of these composites. Firstly, virgin samples with 0.1–5 wt.% of MWCNTs were prepared by injection molding. Then, the HDPE/MWCNT composite waste was mechanically recycled and consecutively reprocessed by injection molding. The experimental results show that, after the first mechanical recycling and reprocessing cycle, the thermal, rheological, mechanical, and electrical properties for the recycled and virgin HDPE/MWCNT composites with 0.1–3 wt.% were rather similar within the experimental error of the measurements. In contrast, the recycled HDPE/MWCNT composites with 5 wt.% showed a reduction in viscosity, mechanical and electrical properties with recycling. After four recycling and reprocessing cycles, degradation in the Young modulus (−35%), tensile strength (−25%), elongation at break (−60%) and electrical conductivity (−2 orders of magnitude) of the HDPE/MWCNT composite with 5 wt.% was observed as compared with the virgin composite. From an industrial perspective, it is feasible to recycle HDPE/MWCNT composite waste by mechanical recycling and use it to manufacture products with favorable mechanical properties, covering insulating, antistatic and semiconducting ranges depending on the MWCNT loading, owing to the protective effect of carbon nanotubes against thermomechanical degradation.

On the 3D Printability of Multi-Walled Carbon Nanotube/High Density Polyethylene Composites

2019 ◽  
Author(s):  
Felicia Stan ◽  
Nicoleta-Violeta Stanciu ◽  
Catalin Fetecau
Keyword(s):  
Carbon Nanotube ◽  
Electrical Properties ◽  
3D Printing ◽  
Shear Viscosity ◽  
High Density Polyethylene ◽  
High Density ◽  
High Shear ◽  
Shear Rates ◽  
Mechanical And Electrical Properties ◽  
Multi Walled Carbon Nanotube

Abstract This study focuses on 3D printing of multi-walled carbon nanotube/high density polyethylene (MWCNT/HDPE) composites. First, rheological properties of 0.1, 1, and 5 wt.% MWCNT/HDPE composites were investigated to estimate the 3D printability window. Second, filaments with 1.75 mm diameter were fabricated and subsequently extruded by a commercial 3D printer. Finally, the filaments and 3D printed parts were tested to correlate the rheological, mechanical, and electrical properties with processing parameters. Experimental results show that flow behavior of MWCNT/HDPE composites is a critical factor affecting the 3D printability. The shear viscosity exhibits good shear thinning behavior at high shear rates and significantly increases with increasing nanotube loading from 0.1 to 5 wt.%, at low shear rates. Reliable MWCNT/HDPE filaments were obtained with smooth surface finish and good mechanical and electrical properties. The 0.1 and 1 wt.% MWCNT/HDPE filaments exhibit very good printing characteristics. However, under the flow conditions of a standard 0.4-mm nozzle, 3D printing of 5 wt.% MWCNT/HDPE filament can be rather difficult primarily due to high shear viscosity and nozzle clogging. Thus, further investigation is needed to fully optimize the 3D printing of MWCNT/HDPE composites.

Performance characteristics of polyethylene/old corrugated container composites reinforced with carbon nanotubes

2016 ◽  
Vol 51 (18) ◽  
pp. 2665-2673 ◽  
Author(s):  
Behzad Kord ◽  
Mehdi Roohani
Keyword(s):  
Carbon Nanotubes ◽  
Carbon Nanotube ◽  
High Density Polyethylene ◽  
Analysis Data ◽  
High Density ◽  
Scanning Calorimetry ◽  
Polyethylene Matrix ◽  
Melt Compounding ◽  
The Impact ◽  
Thermal Stability Of

The physical, mechanical, thermal, and flammability properties of high-density polyethylene/old corrugated container composites reinforced with carbon nanotubes are presented in this study. High-density polyethylene/old corrugated container composites with different loadings of carbon nanotube (0, 1, 3, and 5 phc) were prepared by melt compounding followed by injection molding. Results indicated that the incorporation of carbon nanotube into high-density polyethylene, significantly improved the mechanical properties of the composites. The tensile and flexural properties achieved the maximum values when 3 phc carbon nanotube was added. Meanwhile, the impact strength of the composites progressively decreased with increasing carbon nanotube content. Furthermore, the water absorption and thickness swelling of the samples remarkably reduced with the addition of carbon nanotube. From thermogravimetric analysis data, the presence of carbon nanotube could enhance the thermal stability of the composites, especially the maximum weight loss rate temperature and also the better char residual was obtained at high loading level of carbon nanotube. Simultaneous differential scanning calorimetry thermograms revealed that the thermal degradation temperatures for the samples with carbon nanotube were much higher than those made without carbon nanotube. Moreover, it was found that the addition of carbon nanotube results in a significant enhancement in flame retardancy of the composites. Morphological observations showed that the nanoparticles were predominantly dispersed uniformly within the high-density polyethylene matrix.

Effect of Reprocessing on the Rheological, Electrical and Mechanical Properties of Polypropylene/Carbon Nanotube Composites

2016 ◽  
Author(s):  
Felicia Stan ◽  
Laurentiu Ionut Sandu ◽  
Catalin Fetecau ◽  
Razvan Train Rosculet
Keyword(s):  
Mechanical Properties ◽  
Carbon Nanotubes ◽  
Carbon Nanotube ◽  
Injection Molding ◽  
Young Modulus ◽  
Mechanical Recycling ◽  
Nanotube Composites ◽  
Multi Walled Carbon Nanotubes ◽  
Carbon Nanotube Composites ◽  
Plastic Parts

In the near future, carbon nanotubes containing plastic parts are likely to enter the environment in large quantities and, due to their resistance to degradation, the environmental impact may be even more important than that of similarly shaped plastic products. Thus, there is an immediate need to examine and understand the effect of recycling on the properties of polymer/carbon nanotube composites in order to develop sustainable recycling technologies. In this paper, polypropylene filled with different levels of multi-walled carbon nanotubes (MWCNTs) manufactured by injection molding was closed-loop recycled in order to investigate the effect of recycling and reprocessing on its rheological, electrical and mechanical properties. Preliminary results show that the PP/MWCNT composites keep the flow performance after mechanical recycling. Moreover, the stress and strain at break increase after one reprocessing cycle (mechanical recycling coupled with injection molding) whereas no statistically significant changes in electrical conductivity, Young modulus and tensile strength of the PP/MWCNT composites filled with 1, 3 and 5 wt.% were observed.

An analytical model and ANN simulation for carbon nanotube based ammonium gas sensors

RSC Advances ◽  
2014 ◽  
Vol 4 (69) ◽  
pp. 36896-36904 ◽  
Author(s):  
Elnaz Akbari ◽  
Zolkafle Buntat ◽  
Aria Enzevaee ◽  
Seyed Javad Mirazimiabarghouei ◽  
Mahdi Bahadoran ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Carbon Nanotube ◽  
Electrical Properties ◽  
Analytical Model ◽  
Gas Sensors ◽  
Research Projects ◽  
Nano Technology ◽  
Engineering Research ◽  
Mechanical And Electrical Properties

As one of the most interesting advancements in the field of nano technology, carbon nanotubes (CNTs) have been given special attention because of their remarkable mechanical and electrical properties and are being used in many scientific and engineering research projects.

The Effect of the Diameter of Carbon Nanotube on the Mechanical and Electrical Properties of Cement Mortar

2017 ◽  
Vol 730 ◽  
pp. 479-485 ◽  
Author(s):  
Yan Feng Wang ◽  
Hui Hu ◽  
Chui Qiang Rong
Keyword(s):  
Carbon Nanotubes ◽  
Compressive Strength ◽  
Carbon Nanotube ◽  
Electrical Properties ◽  
Cement Mortar ◽  
Multiwall Carbon Nanotubes ◽  
Cement Matrix ◽  
Sem Image ◽  
Surrounding Matrix ◽  
Mechanical And Electrical Properties

Two different diameter carbon nanotubes were incorporated into cement mortar to investigate the effect on mechanical and electrical properties of composites. Cement-based composites have been prepared from Portland cement with various amounts of multiwall carbon nanotubes (MWCNTS), ranging from 0% to 0.3% by cement weight. In this study, effective dispersion of two different diameter MWCNTS in water were achieved by applying ultrasonic energy and in combination with the use of a surfactant. The flexural and compressive strength of mixes were investigated at age 7 and 28 days. The conductivity of composites were conducted by the four probe method at age of 3 day, 7 day,14 day and 28 day. Results indicated that the two carbon nanotubes can improve the flexural and compressive strength of the composites. Furthermore, the well dispersion carbon nanotube solutions can decrease the resistance of the composites as the better conductive networks are formed in the cement matrix, especially at the later ages. Scanning electron microscopy observation used to observe the fracture surface of specimens containing 0% and 0.3wt% nanotubes indicated that the MWCNTS were well dispersed and there were no obvious agglomerates visible in the matrix. The SEM image revealed good bonding between the MWCNTS and the surrounding matrix.

Sign in / Sign up

Export Citation Format

Share Document