Dispersion Improvement of Carbon Nanotubes in Epoxy Resin Using Amphiphilic Block Copolymers

2010 ◽  
Vol 112 ◽  
pp. 29-36 ◽  
Author(s):  
Anne-Claude Courbaron Gilbert ◽  
Nour-Eddine El Bounia ◽  
Eve Péré ◽  
Laurent Billon ◽  
Christophe Derail
Keyword(s):  
Carbon Nanotubes ◽  
Chemical Modification ◽  
Physical Adsorption ◽  
Stress Transfer ◽  
Controlled Radical Polymerization ◽  
Good Adhesion ◽  
The Matrix ◽  
Nitroxide Mediated Polymerization ◽  
Dispersion Quality

Interface between Carbon NanoTubes (CNT) and epoxy matrix is admitted to play an important role in the dispersion quality and in the mechanical stress transfer. To improve the interfacial adhesion, we propose to chemically graft molecules onto CNT surface. To achieve this chemical modification, a controlled radical polymerization, named Nitroxide Mediated Polymerization NMP, is used to synthesize a diblock copolymer based on Acrylic Acid (PAA block) and Methyl MethAcrylate (PMMA block). In the present paper, this polymerization is performed “in situ”. The PAA block presents a good affinity with the CNT which enable grafting. The PMMA miscibility with epoxy is expected to give a good adhesion - between the CNT and the matrix - and to bring a better dispersion. In order to compare the chemical modification and the physical adsorption of the copolymers onto CNT dispersion, the same block copolymer was synthesized with and without CNT. The copolymer synthesis was controlled and characterized by different methods as NMR 1H (conversion and composition), SEC (molecular weight) and TGA (grafting density). We show that the better dispersion quality and better physical properties have been obtained with grafted CNT.

SOLUBLE CARBON NANOTUBES: FUNDAMENTALS AND APPLICATIONS

2005 ◽  
Vol 04 (01) ◽  
pp. 119-137 ◽  
Author(s):  
NAOTOSHI NAKASHIMA
Keyword(s):  
Carbon Nanotubes ◽  
Chemical Modification ◽  
Physical Adsorption ◽  
Review Article ◽  
Crystal Formation ◽  
Mechanical And Thermal Properties ◽  
Organic Systems ◽  
High Potentials ◽  
Selective Chemical ◽  
Aqueous Micelles

Carbon nanotubes (CNTs) have been in the forefront of nanoscience and nanotechnology because of their remarkable electronic, mechanical, and thermal properties and specific functions. CNTs have high potentials for possible applications in the fields of energy, electronics, IT, and materials. However, because of the insolubility of the nanotubes in solvents, chemical, biochemical, and biological (medical) approaches using these materials have been rather limited. Soluble CNTs in aqueous and organic systems are of interests since they may open the door in such fields. In this review article, (i) the dissolution of CNTs in water and in organic solvents by using chemical modification and physical adsorption and their applications to chemical and biological areas, (ii) separation of metallic SWNTs and semiconducting SWNTs by the combination of individual dissolution of SWNTs and the selective chemical modification, (iii) the preparation of nanotube films and fibers from dissolved/dispersed SWNTs in aqueous micelles, and (iv) CNT liquid crystal formation are summarized.

Effect of Hydroxyapatite Matrix on the Growth of Carbon Nanotubes via a CVD System

2011 ◽  
Vol 685 ◽  
pp. 335-339 ◽  
Author(s):  
Xiao Ying Lu ◽  
Bao Hua Wu ◽  
Yu Jie Liu ◽  
Tian Qiu ◽  
Jie Weng
Keyword(s):  
Carbon Nanotubes ◽  
Carbon Fibers ◽  
Chemical Vapor ◽  
Weight Percent ◽  
The Matrix ◽  
Physical Mixing ◽  
Nano Size ◽  
Walled Cnts ◽  
Chemical Coprecipitation Method

This paper reports the fabrication of carbon nanotubes (CNTs) /hydroxyapatite (HA) composites via in-situ process in a chemical vapor deposition (CVD) system and the effect of HA matrix on the growth of CNTs. When the HA matrix is fabricated by a chemical coprecipitation method, deficient HA (D-HA) crystals in nano size have been observed in these composites. There are about 20% weight percent of multi-walled CNTs with a mean diameter of 40~60 nm. When the matrix used as catalyst for CNTs growth without HA in the same way, no CNTs but solid carbon fibers in submicrometer scale have been produced in these composites. Only Fe and MgO crystals can be observed in these composites. When the HA matrix is fabricated by a physical mixing with the presence of D-HA crystals, hollow CNTs with the diameter of 180~210 nm are also produced in these composites. Fe and MgO besides P2O5, D-HA and C crystals can be observed in the composites.

Effect of carbon nanotube modification on poly (butylene terephthalate)-based composites

2016 ◽  
Vol 70 (6) ◽  
Author(s):  
Agnieszka Piegat ◽  
Anna Jędrzejewska ◽  
Robert Peƚech ◽  
Iwona Peƚech
Keyword(s):  
Mechanical Properties ◽  
Carbon Nanotubes ◽  
Carbon Nanotube ◽  
Lower Amount ◽  
Butylene Terephthalate ◽  
The Matrix ◽  
Multi Walled Carbon Nanotubes ◽  
Modified Carbon Nanotubes ◽  
Walled Carbon Nanotubes

AbstractThe influence of the chemical modification of carbon nanotubes on the mechanical, thermal and electrical properties of poly(butylene terephthalate)-based composites was investigated. Polymer composites based on poly(butylene terephthalate) were obtained via in situ polymerisation or extrusion. Commercially available multi-walled carbon nanotubes (Nanocyl NC7000) at different loadings (mass %: 0.05, 0.25, 1, 2) were used as fillers. The functionalisation process took place under a chlorine atmosphere followed by a reaction with sodium hydroxide. The effect of carbon nanotube modification was analysed according to the changes in the polymer thermal and mechanical properties. An addition of modified carbon nanotubes in the amount of 0.05 mass % improved the mechanical properties of the composites in terms of both Young’s modulus and tensile strength by 5–10 % and 17–30 % compared with composites with unmodified carbon nanotubes and neat poly(butylene terephthalate), respectively. The in situ method of composite preparation was a more effective technique for enhancing the matrix–filler interactions, although a significantly lower amount of fillers were used than in the extrusion method.

scholarly journals Influence of Silanization Treatment on Thermomechanical Properties of Multiwalled Carbon Nanotubes: Poly(methylmethacrylate) Nanocomposites

2011 ◽  
Vol 2011 ◽  
pp. 1-9 ◽  
Author(s):  
Carlos Velasco-Santos ◽  
Ana Laura Martinez-Hernandez ◽  
Witold Brostow ◽  
Victor M. Castaño
Keyword(s):  
Carbon Nanotubes ◽  
Multiwalled Carbon Nanotubes ◽  
Polymer Matrix ◽  
Mechanical Load ◽  
Mechanical Analysis ◽  
Thermomechanical Properties ◽  
Multiwalled Carbon ◽  
Dynamical Mechanical Analysis ◽  
The Matrix

Unfunctionalized and silanized multiwalled carbon nanotubes (MWNTs) were incorporated in poly(methylmethacrylate) matrices usingin situpolymerization. Polymer-compatible functional groups on carbon nanotube (CNT) surfaces were characterized by infrared spectroscopy. These chemical moieties improve interaction at interfaces, allowing transfer of mechanical load between the matrix and the dispersed phase as reflected in the resulting improved mechanical and thermophysical properties. The composites were characterized by Raman spectroscopy to evaluate molecular level interactions and dynamical mechanical analysis. Composites with silanized CNTs have higher storage modulus (E′) than polymer reinforced with unfunctionalized nanotubes. Considering the average of the samples, only 1 wt.% of silanized nanotubes provides an increase inE′ of 165% at room temperature with respect to polymer matrix, and the increments reached are by a factor of 6.8 and 13.6 over the polymer matrix at 80°C and 90°C, respectively. 1 wt% of silanized CNTs increases the glass transition temperature of polymer matrix around 30°C. Microscratch testing results of composites show that unfunctionalized CNTs cause deeper penetration of the indenter than polymer matrix at the same force; however, the composites developed with silanized CNTs present more regular behavior than polymer reinforced with unfunctionalized CNTs.

Stress Analysis of Carbon Nanotubes Reinforced Nanocomposites

2013 ◽  
Vol 284-287 ◽  
pp. 357-361
Author(s):  
Shiuh Chuan Her ◽  
Shou Jan Liu
Keyword(s):  
Carbon Nanotubes ◽  
Carbon Nanotube ◽  
Stress Analysis ◽  
Volume Fraction ◽  
Interfacial Shear Stress ◽  
Stress Transfer ◽  
Large Volume Fraction ◽  
Concentric Cylinders ◽  
The Matrix ◽  
Lag Model

Stress transfer in the carbon nanotube reinforced nanocomposites is investigated in this work. The model consists of two concentric cylinders, namely, a single-walled carbon nanotube cylinder (SWCNT) and a matrix cylinder, as the representative volume element (RVE). The stress analysis is performed using the shear lag model for the axisymmetric RVE. Analytical solutions for the axial normal stresses in the SWCNT and matrix, and the interfacial shear stress across the SWCNT/matrix interface are obtained. Numerical results show that using a large volume fraction improves the efficiency of the stress transfer from the matrix to the carbon nanotubes.

EFFICIENT LOAD TRANSFER TO FUNCTIONALIZED CARBON NANOTUBES AS REINFORCEMENT IN POLYMER NANOCOMPOSITES

2009 ◽  
Vol 23 (06n07) ◽  
pp. 1401-1406 ◽  
Author(s):  
ALI NABIPOUR CHAKOLI ◽  
WEI CAI ◽  
SUI JIEHE ◽  
JIANG TAO FENG
Keyword(s):  
Carbon Nanotubes ◽  
Load Transfer ◽  
Tensile Load ◽  
Random Copolymers ◽  
Multiwalled Carbon ◽  
Pristine Mwcnts ◽  
The Matrix ◽  
Effective Reinforcement ◽  
Functionalized Mwcnts

Multiwalled carbon nanotubes (MWCNTs) grafted with poly(L-lactide-e-caprolactone) (PCLA) were synthesized by in situ ring opening polymerization and used as a reinforcement for neat PCLA. The analyzed data revealed that the applied tensile load on the composite was transferred to the functionalized MWCNTs, leading to a strain failure of the MWCNTs rather than an adhesive failure between the MWCNTs and the matrix. In comparison between the functionalized and pristine MWCNTs, as reinforcement materials for PCLA random copolymers (80% L-lactide (LA), 20% e-caprolactone (CL)) (PCLAR80), the functionalized MWCNTs are more effective reinforcement materials than pristine MWCNTs. In comparison with the neat PCLAR80, the increasing in tensile strength (28.03%) and elongation at failure (49.6%) when functionalized MWCNT loading reaches 1.0 wt%, indicate that an effective reinforcement of the MWCNT-OH-g-PCLA .

Polyethylene Functionalized Multi-Walled Carbon Nanotubes via In Situ Polymerization

2012 ◽  
Vol 573-574 ◽  
pp. 1163-1166
Author(s):  
Shi Yun Li ◽  
De Sheng Hu
Keyword(s):  
Mechanical Properties ◽  
Carbon Nanotubes ◽  
Storage Modulus ◽  
Raman Spectra ◽  
In Situ Polymerization ◽  
Thermal And Mechanical Properties ◽  
The Matrix ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes

The MWNTs/PE nanocomposites are prepared by in situ polymerization with mulltiwalled carbon nanotubes (MWNTs) supported Cp2ZrCl2 catalyst and MAO as cocatalyst. The SEM and AFM results show that MWNTs are exfoliated and homogenously dispersed in PE matrix by the in situ polymerization. The up-shifting of the G band in Raman spectra show the strong compressive forces associated with PE chains on the MWNTs. The storage modulus of the MWNTs/PE nanocomposite can be increased by 160% even at low amount of MWNTs (0.2 wt %) due to MWNTs well-dispersed and exfoliated in the matrix. The TGA and DMA tests point to significant improvements on thermal and mechanical properties of the PE/MWNTs nanocomposites compared to pure PE.

scholarly journals Supramolecular ionic polymer/carbon nanotube composite hydrogels with enhanced electromechanical performance

2020 ◽  
Vol 9 (1) ◽  
pp. 478-488 ◽  
Author(s):  
Yun-Fei Zhang ◽  
Fei-Peng Du ◽  
Ling Chen ◽  
Ka-Wai Yeung ◽  
Yuqing Dong ◽  
...  
Keyword(s):  
Carbon Nanotube ◽  
Ion Mobility ◽  
Artificial Muscles ◽  
Ionic Polymer ◽  
Composite Hydrogels ◽  
The Matrix ◽  
Electromechanical Performance ◽  
Carbon Nanotube Composite ◽  
Robotic Devices

AbstractElectroactive hydrogels have received increasing attention due to the possibility of being used in biomimetics, such as for soft robotics and artificial muscles. However, the applications are hindered by the poor mechanical properties and slow response time. To address these issues, in this study, supramolecular ionic polymer–carbon nanotube (SIPC) composite hydrogels were fabricated via in situ free radical polymerization. The polymer matrix consisted of carbon nanotubes (CNTs), styrene sulfonic sodium (SSNa), β-cyclodextrin (β-CD)-grafted acrylamide, and ferrocene (Fc)-grafted acrylamide, with the incorporation of SSNa serving as the ionic source. On applying an external voltage, the ions accumulate on one side of the matrix, leading to localized swelling and bending of the structure. Therefore, a controllable and reversible actuation can be achieved by changing the applied voltage. The tensile strength of the SIPC was improved by over 300%, from 12 to 49 kPa, due to the reinforcement effect of the CNTs and the supramolecular host–guest interactions between the β-CD and Fc moieties. The inclusion of CNTs not only improved the tensile properties but also enhanced the ion mobility, which lead to a faster electromechanical response. The presented electro-responsive composite hydrogel shows a high potential for the development of robotic devices and soft smart components for sensing and actuating applications.

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