scholarly journals Mechanical And Thermal Behavior of Carbon Nanotubes/Vinyl Ester Nanocomposites

2019 ◽  
Vol 56 (4) ◽  
pp. 735-743 ◽  
Author(s):  
Adrian Cotet ◽  
Marian Bastiurea ◽  
Gabriel Andrei ◽  
Alina Cantaragiu ◽  
Anton Hadar
Keyword(s):  
Carbon Nanotubes ◽  
Thermal Behavior ◽  
Vinyl Ester ◽  
Coefficient Of Thermal Expansion ◽  
Mechanical Tests ◽  
Bending Test ◽  
Vinyl Ester Resin ◽  
Scanning Calorimetry ◽  
Sem Images ◽  
Walled Carbon Nanotubes

Single walled carbon nanotubes (SWCNT) and multi walled carbon nanotubes (MWCNT)/ vinyl ester nanocomposites with three different contents of carbon nanotubes (CNTs) have been prepared by the simple melt-compounding method. A fine and homogeneous dispersion of CNTs throughout vinyl ester resin has been noticed by SEM images. Two mechanical tests (compression and three point bending test) show that, compared to neat vinyl ester resin, compression modulus and compression strength of the nanocomposites have been significantly improved by about 9% and 14%, respectively, when incorporating only 0.15 wt.% MWCNTs. Furthermore, thermal behavior of SWCNT and MWCNT/ vinyl ester nanocomposites has been investigated and discussed based on differential scanning calorimetry (DSC) and thermo- mechanical analysis (TMA). Glass transition temperature (Tg) and coefficient of thermal expansion (CTE) have been increased and decreased, respectively, with increasing of CNTs content.

Cure and Dynamic-Mechanical Behaviors of Vinyl Ester Resinfilled with Multi-Walled Carbon Nanotubes

2010 ◽  
Vol 150-151 ◽  
pp. 1413-1416 ◽  
Author(s):  
Hong Yan Chen ◽  
Zhen Xing Kong ◽  
Ji Hui Wang
Keyword(s):  
Carbon Nanotubes ◽  
Vinyl Ester ◽  
Mechanical Response ◽  
Cure Kinetics ◽  
Crosslinking Density ◽  
Vinyl Ester Resin ◽  
Scanning Calorimetry ◽  
Dynamic Mechanical ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes

The cure kinetics of Derakane 411-350, a kind of vinyl ester resin, and its suspensions containing multi-walled carbon nanotubes( MWCNTs) were investigated via non-isothermal dynamic scanning calorimetry (DSC) measurements. The results showed that incorporation of MWCNTs into vinyl ester resin excessively reduces polymerization degree and crosslinking density of vinyl ester resin. For suppressing the negative effect caused by nanotubes, the higher temperature initiator combined with the initiator MEKP was used. Dynamic-mechanical Behavior testing was then carried out on the cured sample in order to relate the curing behavior of MWCNTs modified resin suspensions to mechanical response of their resulting nanocomposites. It was revealed that nanocomposites containing MWCNTs possessed larger storage modulus values as well as higher glass transition temperatures (Tg) as compared to those without MWCNTs after using mixed intiators system to improve the degree of cure.

Compression Moulding of Thermoplastic Nanocomposites Filled with MWCNT

2017 ◽  
Vol 25 (8) ◽  
pp. 611-620 ◽  
Author(s):  
Fabrizio Quadrini ◽  
Denise Bellisario ◽  
Loredana Santo ◽  
Felicia Stan ◽  
Fetecau Catalin
Keyword(s):  
Carbon Nanotubes ◽  
Differential Scanning Calorimetry ◽  
Filler Content ◽  
Thermoplastic Polyurethane ◽  
Mechanical Tests ◽  
Compression Moulding ◽  
Scanning Calorimetry ◽  
Melt Mixing ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes

Multi-walled carbon-nanotubes (MWCNTs) were melt-mixed with three different thermoplastic matrices (polypropylene, PP, polycarbonate, PC, and thermoplastic polyurethane, TPU) to produce nanocomposites with three different filler contents (1, 3, and 5 wt.%). Initial nanocomposite blends (in the shape of pellets) were tested under differential scanning calorimetry to evaluate the effect of the melt mixing stage. Nanocomposite samples were produced by compression moulding in a laboratory-scale system, and were tested with quasi-static (bending, indentation), and dynamic mechanical tests as well as with friction tests. The results showed the effect of the filler content on the mechanical and functional properties of the nanocomposites. Compression moulding appeared to be a valuable solution to manufacture thermoplastic nanocomposites when injection moulding leads to loss of performance. MWCNT-filled thermoplastics could be used also for structural and functional uses despite, the present predominance of electrical applications.

scholarly journals Structure and Mechanical Properties of Multi-Walled Carbon Nanotubes-Filled Isotactic Polypropylene Composites Treated by Pressurization at Different Rates

Polymers ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 1294 ◽  
Author(s):  
Xiaoting Li ◽  
Wenxia Jia ◽  
Beibei Dong ◽  
Huan Yuan ◽  
Fengmei Su ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Isotactic Polypropylene ◽  
Mechanical Tests ◽  
High Yield ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Polypropylene Composites ◽  
Pressurization Rate ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes

Isotactic polypropylene filled with 1 wt.% multi-walled carbon nanotubes (iPP/MWCNTs) were prepared, and their crystallization behavior induced by pressurizing to 2.0 GPa with adjustable rates from 2.5 to 1.3 × 104 MPa/s was studied. The obtained samples were characterized by combining wide angle X-ray diffraction, small angle X-ray scattering, differential scanning calorimetry, transmission electron microscopy and atomic force microscopy techniques. It was found that pressurization is a simple way to prepare iPP/MWCNTs composites in mesophase, γ-phase, or their blends. Two threshold pressurization rates marked as R1 and R2 were identified, while R1 corresponds to the onset of mesomorphic iPP formation. When the pressurization rate is lower than R1 only γ-phase generates, with its increasing mesophase begins to generate and coexist with γ-phase, and if it exceeds R2 only mesophase can generate. When iPP/MWCNTs crystallized in γ-phase, compared with the neat iPP, the existence of MWCNTs can promote the nucleation of γ-phase, leading to the formation of γ-crystal with thicker lamellae. If iPP/MWCNTs solidified in mesophase, MWCNTs can decrease the growth rate of the nodular structure, leading to the formation of mesophase with smaller nodular domains (about 9.4 nm). Mechanical tests reveal that, γ-iPP/MWCNTs composites prepared by slow pressurization display high Young’s modulus, high yield strength and high elongation at break, and meso-iPP/MWCNTs samples have excellent deformability because of the existence of nodular morphology. In this sense, the pressurization method is proved to be an efficient approach to regulate the crystalline structure and the properties of iPP/MWCNTs composites.

scholarly journals Vacuum Casting and Mechanical Characterization of Nanocomposites from Epoxy and Oxidized Multi-Walled Carbon Nanotubes

Molecules ◽  
2019 ◽  
Vol 24 (3) ◽  
pp. 510
Author(s):  
Gerald Singer ◽  
Philipp Siedlaczek ◽  
Gerhard Sinn ◽  
Patrick Kirner ◽  
Reinhard Schuller ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Mechanical Tests ◽  
Image Correlation ◽  
Sem Images ◽  
Vacuum Casting ◽  
Multi Walled Carbon Nanotubes ◽  
Properties Of Materials ◽  
Walled Carbon Nanotubes

Sample preparation is an important step when testing the mechanical properties of materials. Especially, when carbon nanotubes (CNT) are added to epoxy resin, the increase in viscosity complicates the casting of testing specimens. We present a vacuum casting approach for different geometries in order to produce specimens from functional nanocomposites that consist of epoxy matrix and oxidized multi-walled carbon nanotubes (MWCNTs). The nanocomposites were characterized with various mechanical tests that showed improved fracture toughness, bending and tensile properties performance by addition of oxidized MWCNTs. Strengthening mechanisms were analyzed by SEM images of fracture surfaces and in-situ imaging by digital image correlation (DIC).

Effects of Carbon Nanotube Functionalization on the Mechanical Properties of Vinyl Ester Composites

2011 ◽  
Vol 233-235 ◽  
pp. 2315-2318 ◽  
Author(s):  
Hong Yan Chen ◽  
Hua Bo Huang ◽  
Ji Hui Wang
Keyword(s):  
Carbon Nanotubes ◽  
Vinyl Ester ◽  
Interfacial Interaction ◽  
Resin Matrix ◽  
Acid Mixture ◽  
Vinyl Ester Resin ◽  
Chemical Functionalization ◽  
Transmission Electron ◽  
Ft Ir ◽  
Walled Carbon Nanotubes

Chemically functionalized muliti-walled carbon nanotubes (MWCNTs)/vinyl ester resin (VE) nanocomposites were prepared. MWCNTs were first treated by H2SO4/HNO3 acid mixture, and then carboxylated MWCNTs were grafted of methacrylic acid glycidyl ester (GMA). Raman microscopy and Fourier transform infrared spectroscopy (FT-IR) analyses proved the effectivenss of acid-treatment and chemical functionalization. Furthermore, chemical functionalization did not greatly disrupt carbon nanotubes structure and Transmission electron microscopy (TEM) showed that there was a GMA thin layer on the MWCNTs surface, which contributes to the homogenous dispersion of MWCNTs in vinyl ester resin matrix and the CNTs-VE interfacial interaction. Thus the nanocomposites containing MWCNT-GMA possess larger storage modulus values as well as higher glass transition temperatures (Tg).

INFLUENCE OF DEAGGLOMERATION STATES OF CARBON NANOTUBES ON THE THERMAL AND MECHANICAL PROPERTIES OF CARBON NANOTUBE-REINFORCED POLYETHYLENE OXIDE

2009 ◽  
Vol 08 (01n02) ◽  
pp. 23-27 ◽  
Author(s):  
KWABENA A. NARH ◽  
AHMED-TIJANI AGWEDICHAM ◽  
LAILA J. JALLO ◽  
KYONG Y. RHEE ◽  
JI H. LEE
Keyword(s):  
Mechanical Properties ◽  
Carbon Nanotubes ◽  
Polyethylene Oxide ◽  
High Speed ◽  
Test Results ◽  
Scanning Calorimetry ◽  
Sem Images ◽  
Ultrasonic Probe ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes

Composites of polyethylene oxide and carbon nanotubes were produced by first deagglomerating highly agglomerated multi-walled carbon nanotubes in water, using a high-intensity ultrasonic probe, and then mixing with a solution of the polymer using a high-speed mixer. The deagglomeration of the nanotubes was carried out at different amplitudes of the vibrating ultrasonic probe. Differential scanning calorimetry results show an increase in melting temperature with increase in amplitude of sonication. Also, tensile test results show improved mechanical properties, with increased degree of deagglomeration of the nanotubes. SEM images show that the extent of nanotubes dispersion in the polymer matrix correlates with the extent of deagglomeration.

scholarly journals Multifunctional Ionogels Incorporated with Lanthanide (Eu3+, Tb3+) Complexes Covalently Modified Multi-Walled Carbon Nanotubes

Polymers ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 1099 ◽  
Author(s):  
Qiuping Li
Keyword(s):  
Carbon Nanotubes ◽  
Ionic Liquids ◽  
Uv Light ◽  
Green Emission ◽  
Sem Images ◽  
Hybrid Gels ◽  
Multi Walled Carbon Nanotubes ◽  
Electric Materials ◽  
Walled Carbon Nanotubes ◽  
Functionalized Mwcnts

Ionogels refer to an emerging composite material made from the confinement of ionic liquids within some specific cross-linked network matrices. They have potential applications in areas such as electrochemical and optical-electric materials. Incorporation of lanthanide (Eu3+, Tb3+) complexes covalently functionalized multi-walled carbon nanotubes (MWCNTs) in ionogels provide new ideas to design and synthesize novel luminescent hybrid materials that have excellent characteristics of luminescence and ionic conductivity. Here, the multifunctional ionogels were synthesized by confining an ionic liquid and the rare earth functionalized MWCNTs in the cross-linked polymethyl methacrylate (PMMA) networks, resulting in a novel optical/electric multifunctional hybrid material. The SEM images and digital photographs suggest that the lanthanide functionalized MWCNTs are evenly dispersed in the hybrid matrices, thus leading to a certain transparency bulky gel. The resulting ionogels exhibit certain viscosity and flexibility, and display an intense red/green emission under UV-light irradiation. The intrinsic conductibility of the embedded ionic liquids and carbon nanotubes in conjunction with the outstanding photoluminescent properties of lanthanide complexes makes the soft hybrid gels a material with great potential and valuable application in the field of optical-electric materials.

Thermal Behavior of Double-Walled Carbon Nanotubes and Evidence of Thermal Rectification

2012 ◽  
Vol 116 (7) ◽  
pp. 4449-4454 ◽  
Author(s):  
Khoa Bui ◽  
Huong Nguyen ◽  
Cedric Cousin ◽  
Alberto Striolo ◽  
Dimitrios V. Papavassiliou
Keyword(s):  
Carbon Nanotubes ◽  
Thermal Behavior ◽  
Thermal Rectification ◽  
Double Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes

scholarly journals Electrodeposition of Sn and Sn Composites with Carbon Materials Using Choline Chloride-Based Ionic Liquids

Coatings ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 798
Author(s):  
Ana T. S. C. Brandão ◽  
Liana Anicai ◽  
Oana Andreea Lazar ◽  
Sabrina Rosoiu ◽  
Aida Pantazi ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Carbon Materials ◽  
Electrochemical Impedance ◽  
Choline Chloride ◽  
Composite Films ◽  
Growth Stages ◽  
Initial Growth ◽  
Sem Images ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes

Nano carbons, such as graphene and carbon nanotubes, show very interesting electrochemical properties and are becoming a focus of interest in many areas, including electrodeposition of carbon–metal composites for battery application. The aim of this study was to incorporate carbon materials (namely oxidized multi-walled carbon nanotubes (ox-MWCNT), pristine multi-walled carbon nanotubes (P-MWCNT), and reduced graphene oxide (rGO)) into a metallic tin matrix. Formation of the carbon–tin composite materials was achieved by electrodeposition from a choline chloride-based ionic solvent. The different structures and treatments of the carbon materials will create metallic composites with different characteristics. The electrochemical characterization of Sn and Sn composites was performed using chronoamperometry, potentiometry, electrochemical impedance, and cyclic voltammetry. The initial growth stages of Sn and Sn composites were characterized by a glassy-carbon (GC) electrode surface. Nucleation studies were carried out, and the effect of the carbon materials was characterized using the Scharifker and Hills (SH) and Scharifker and Mostany (SM) models. Through a non-linear fitting method, it was shown that the nucleation of Sn and Sn composites on a GC surface occurred through a 3D instantaneous process with growth controlled by diffusion. According to Raman and XRD analysis, carbon materials were successfully incorporated at the Sn matrix. AFM and SEM images showed that the carbon incorporation influences the coverage of the surface as well as the size and shape of the agglomerate. From the analysis of the corrosion tests, it is possible to say that Sn-composite films exhibit a comparable or slightly better corrosion performance as compared to pure Sn films.

scholarly journals Humic acid assisted stabilization of dispersed single-walled carbon nanotubes in cementitious composites

2019 ◽  
Vol 8 (1) ◽  
pp. 513-522 ◽  
Author(s):  
Tao Hu ◽  
Hongwen Jing ◽  
Luan Li ◽  
Qian Yin ◽  
Xinshuai Shi ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Humic Acid ◽  
Mechanical Performance ◽  
Single Walled Carbon Nanotubes ◽  
Cementitious Composites ◽  
Cement Slurry ◽  
Sem Images ◽  
Single Walled Carbon ◽  
Alkaline Environment ◽  
Walled Carbon Nanotubes

AbstractSignificant research has been done in recent decades in the field of the dispersion of carbon nanotubes in aqueous solutions and the reinforcement of ordinary Portland cement (OPC). However, the cementitious mixture, as an alkaline environment, easily leads to the re-agglomeration of dispersed single-walled carbon nanotubes (SWCNTs) and influences their enhancing effects. Humic acid (HA) is a type of natural organic matter which can assist the stabilization of dispersed single-walled carbon nanotubes in cementitious composites. The present study characterizes the influence of HA in stabilizing the dispersion of SWCNTs by means of ultraviolet spectrophotometer tests. The fluidity of fresh cement slurry and mechanical performance of hardened OPC pastes were measured to better illustrate the dispersion of SWCNTs in real cement composites. The results not only reveal that the addition of an alkaline environment to the SWCNT suspensions results in a rapid decrease of the dispersion, but also suggest that the appropriate content of HA (0.12 wt.%) can play a significant role in stabilizing the dispersion of SWCNTs. When the mixed hybrid of SWCNTs and HA with a concentration of HA/c equal to 0.05 wt.% is used, the fluidity of the fresh cement slurry experiences a maximum decline and this mixture content of materials will dramatically increase the compressive and flexural strength by about 31% and 48%, which indicates that more SWCNTs are in a dispersed state under this concentration. SEM images further prove that a suitable HA/c can inhibit the expansion of cracks in the cementitious composites.

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