scholarly journals Thermal, Rheological, Mechanical, and Electrical Properties of Polypropylene/Multi-Walled Carbon Nanotube Nanocomposites

Polymers ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 187
Author(s):  
Nicoleta-Violeta Stanciu ◽  
Felicia Stan ◽  
Ionut-Laurentiu Sandu ◽  
Catalin Fetecau ◽  
Adriana-Madalina Turcanu
Keyword(s):  
Thermal Conductivity ◽  
Electrical Properties ◽  
Shear Viscosity ◽  
Specific Volume ◽  
Tensile Modulus ◽  
Mechanical And Electrical Properties ◽  
Property Data ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes ◽  
Mwcnt Loading

In this paper, nanocomposites based on polypropylene (PP) filled with up to 5 wt.% of multi-walled carbon nanotubes (MWCNTs) were investigated for determining the material property data used in numerical simulation of manufacturing processes such as the injection molding and extrusion. PP/MWCNT nanocomposite pellets were characterized for rheological behavior, crystallinity, specific volume and thermal conductivity, while injection-molded samples were characterized for mechanical and electrical properties. The addition of MWCNTs does not significantly change the melting and crystallization behavior of the PP/MWCNT nanocomposites. The effect of MWCNTs on melt shear viscosity is more pronounced at low shear rates and MWCNT loadings of 1–5 wt.%. However, with the addition of up to 5 wt.% of MWCNTs, the PP/MWCNT nanocomposite still behaves like a non-Newtonian fluid. The specific volume of the PP/MWCNT nanocomposites decreases with increasing MWCNT loading, especially in the MWCNT range of 1–5 wt.%, indicating better dimensional stability. The thermal conductivity, depending on the pressure, MWCNT wt.% and temperature, did not exceed 0.35 W/m·K. The PP/MWCNT nanocomposite is electrical non-conductive up to 3 wt.%, whereas after the percolating path is created, the nanocomposite with 5 wt.% becomes semi-conductive with an electrical conductivity of 10−1 S/m. The tensile modulus, tensile strength and stress at break increase with increasing MWCNT loading, whereas the elongation at break significantly decreases with increasing MWCNT loading. The Cross and modified 2-domain Tait models are suitable for predicting the melt shear viscosity and specific volume as a function of MWCNTs, respectively. These results enable users to integrate the PP/MWCNT nanocomposites into computer aided engineering analysis.

Investigation of Structure-Property Relationships in Thermoplastic Polyurethane/Multiwalled Carbon Nanotube Composites

2017 ◽  
Author(s):  
Felicia Stan ◽  
Catalin Fetecau ◽  
Nicoleta V. Stanciu ◽  
Razvan T. Rosculet ◽  
Laurentiu I. Sandu
Keyword(s):  
Electrical Properties ◽  
Shear Viscosity ◽  
Thermoplastic Polyurethane ◽  
Structure Property ◽  
Multiwalled Carbon ◽  
Structure Property Relationships ◽  
Mechanical And Electrical Properties ◽  
High Shear Rates ◽  
Nanotube Composites ◽  
Multi Walled Carbon Nanotubes

In this study, the structure-property relationships in thermoplastic polyurethane (TPU) filled with multi-walled carbon nanotubes (MWCNTs) were investigated. Firstly, the contribution of MWCNTs to the melt shear viscosity and the pressure-volume-temperature (pVT) behavior was investigated. Secondly, injection-molded samples and 2 mm diameter filaments of TPU/MWCNT composites were fabricated and their mechanical and electrical properties analyzed. It was found that the melt processability of TPU/MWCNT composites is not affected by the addition of a small amount (1–5 wt.%) of MWCNTs, all composites displaying shear-thinning at high shear rates. The mechanical and electrical properties of the TPU/MWCNT composites were substantially enhanced with the addition of MWCNTs. However, the conductivity values of composites processed by injection molding were two and three orders of magnitude lower than those of composites processed by extrusion, highlighting the role of melt shear viscosity on the dispersion and agglomeration of nanotubes.

scholarly journals Development of Conductive Gelatine-Methacrylate Inks for Two-Photon Polymerisation

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1038
Author(s):  
Paola Sanjuan-Alberte ◽  
Jayasheelan Vaithilingam ◽  
Jonathan C. Moore ◽  
Ricky D. Wildman ◽  
Christopher J. Tuck ◽  
...  
Keyword(s):  
Electrical Properties ◽  
Electrochemical Impedance ◽  
Induced Pluripotent Stem Cell ◽  
Precise Control ◽  
Two Photon ◽  
Ability To Act ◽  
Multi Walled Carbon Nanotubes ◽  
Induced Pluripotent ◽  
Conductive Hydrogels ◽  
Walled Carbon Nanotubes

Conductive hydrogel-based materials are attracting considerable interest for bioelectronic applications due to their ability to act as more compatible soft interfaces between biological and electrical systems. Despite significant advances that are being achieved in the manufacture of hydrogels, precise control over the topographies and architectures remains challenging. In this work, we present for the first time a strategy to manufacture structures with resolutions in the micro-/nanoscale based on hydrogels with enhanced electrical properties. Gelatine methacrylate (GelMa)-based inks were formulated for two-photon polymerisation (2PP). The electrical properties of this material were improved, compared to pristine GelMa, by dispersion of multi-walled carbon nanotubes (MWCNTs) acting as conductive nanofillers, which was confirmed by electrochemical impedance spectroscopy and cyclic voltammetry. This material was also confirmed to support human induced pluripotent stem cell-derived cardiomyocyte (hPSC-CMs) viability and growth. Ultra-thin film structures of 10 µm thickness and scaffolds were manufactured by 2PP, demonstrating the potential of this method in areas spanning tissue engineering and bioelectronics. Though further developments in the instrumentation are required to manufacture more complex structures, this work presents an innovative approach to the manufacture of conductive hydrogels in extremely low resolution.

scholarly journals Fabrication of carbon nanotube-reinforced mortar specimens: evaluation of mechanical and pressure-sensitive properties

2018 ◽  
Vol 188 ◽  
pp. 01019 ◽  
Author(s):  
Evangelia K. Karaxi ◽  
Irene A. Kanellopoulou ◽  
Anna Karatza ◽  
Ioannis A. Kartsonakis ◽  
Costas A. Charitidis
Keyword(s):  
Cementitious Composites ◽  
Mixing Process ◽  
Mechanical And Electrical Properties ◽  
Pressure Sensitive ◽  
Polar Media ◽  
Significant Research ◽  
Multi Walled Carbon Nanotubes ◽  
Carbon Based Nanomaterials ◽  
Walled Carbon Nanotubes ◽  
Carbon Based

Carbon-based nanomaterials are promising reinforcing elements for the development of “smart” self-sensing cementitious composites due to their exceptional mechanical and electrical properties. Significant research efforts have been committed on the synthesis of cement-based composite materials reinforced with carbonaceous nanostructures, covering every aspect of the production process (type of nanomaterial, mixing process, electrode type, measurement methods etc.). In this study, the aim is to develop a well-defined repeatable procedure for the fabrication as well as the evaluation of pressure-sensitive properties of intrinsically self-sensing cementitious composites incorporating carbon- based nanomaterials. Highly functionalized multi-walled carbon nanotubes with increased dispersibility in polar media were used in the development of advanced reinforced mortar specimens which increased their mechanical properties and provided repeatable pressure-sensitive properties.

Sign in / Sign up

Export Citation Format

Share Document