Improvement on Dispersion of Carbon Nanotubes in Polymer Matrix by Using the Solvent with a Low Boiling Point

2018 ◽  
Vol 939 ◽  
pp. 170-176
Author(s):  
Xiang Fu ◽  
Maximiano Ramos ◽  
Ahmed M. Al-Jumaily ◽  
Xi Yong Huang ◽  
Nargis Chowdhury

Polymer nanocomposites based on carbon nanotubes attract a great deal of attention recently due to their excellent performance. The dispersion state of CNTs embedded in the matrix is the primary and key issue to realize the potential of the nanocomposite. Here, this paper considers how the boiling point of solvent affects the performance of the nanocomposite when the ultrasonication dispersion method is employed. It is found that solvent with a low boiling point is conducive to save evaporation time so that CNTs can maintain the homogenous dispersion state as much as possible after ultrasonication. Therefore, the stretchability and tensile strength can be improved, while the electrical conductivity has an obvious enhancement as well.

2011 ◽  
Vol 471-472 ◽  
pp. 157-161
Author(s):  
R. Nishata Royan ◽  
Abu Bakar Sulong ◽  
Jaafar Sahari

Carbon nanotubes have excellent mechanical and electrical properties, and are also a good reinforcement material for composites than conventional materials. The matrix used in this study was epoxy and reinforcement filler in multi-walled carbon nanotubes (MWCNTs). The different MWCNTs loading concentrations (0 ~ 10 wt. %) were added into the epoxy resin. The dispersion of MWCNTs in epoxy resin was conducted using high speed mixer through mechanical shearing mechanism. The mixture of epoxy/MWNTs suspension was poured into the mold and compression molding was conducted for fabrication of MWCNTs/epoxy nanocomposites. The electrical conductivity of nanocomposite by variation of CNTs concentration was measured by the four point probe. Dispersion state of CNTs in epoxy matrix was observed on fractured surface by scanning electron microscopic. Hardness of the composite was tested using the Dinamic Ultra Micro Hardness machine. Non conductive epoxy polymer becomes conductor as addition of CNTs.. Electrical conductivity of nanocomposite plates increased with increasing CNTs concentration. Agglomerations of CNTs were observed on fractured surfaces. This phenomenon due to CNTs which used in this study was at as produced state where no modification is being done on it. Long and entanglement of individual CNTs easily lead to agglomerations. Van de Wall’s force interactions between CNTs also contribute to the agglomerations of CNTs. Hardness of the composite increases with the CNTs loading concentrations until it reaches a maximum peak at the composition of 5wt% of CNTs but the hardness decreases rapidly with loading greater than 5wt% of CNTs.


2016 ◽  
Vol 50 (23) ◽  
pp. 3283-3290 ◽  
Author(s):  
K Abazine ◽  
H Anakiou ◽  
M El Hasnaoui ◽  
MPF Graça ◽  
MA Fonseca ◽  
...  

2018 ◽  
Vol 91 (4) ◽  
pp. 757-766 ◽  
Author(s):  
Fanzhu Li ◽  
Huan Zhang ◽  
Tiantian Li ◽  
Jun Liu ◽  
Yangyang Gao ◽  
...  

ABSTRACT It is very important to improve the electrical conductivity of polymer nanocomposites, which can widen their application. The effect of the nanofiller shape on the relationship between the nanofiller microstructure and the conductive probability of the nanofiller filled polymer nanocomposites (PNCs) has been investigated in detail by employing a coarse-grained molecular dynamics simulation. Four kinds of nanofiller shapes are considered: rod filler, Y filler, X filler, and sphere filler. First, the mean square radius of gyration gradually decreases from rod filler, Y filler, X filler, to sphere filler, which reflects the highest aspect ratio for rod filler. Meanwhile, the dispersion state of the nanofiller is relatively uniform in the matrix. The conductive probability (denoted by the formation probability of the conductive network) is adopted to stand for the conductive property. The results show that the conductive probability gradually decreases from rod filler, Y filler, X filler, to sphere filler, which is attributed to their gradually decreased size. In summary, the nanofiller shape affects the electric conductive property of PNCs.


2021 ◽  
Vol 41 (9) ◽  
pp. 827-834
Author(s):  
Xin Guo ◽  
Le Kang ◽  
Lishui Sun ◽  
Li Liu ◽  
Guangye Liu

Abstract Nanocomposites of single-wall carbon nanotubes in isobutylene isoprene rubber (IIR/SWCNTs) were successfully prepared by a simple and green wet process. The traditional melt mixing process and organic solvent dissolution suffered from unable to effectively disperse the SWCNTs of tangled structure, and degradation of polymer molecules, respectively. Our process very well avoided these two problems. The SWCNTs aqueous solutions emulsified by polyoxyethylene octyl phenol ether (OP-10) were firstly mixed and compounded with IIR rubber at a relatively high temperature, followed by the second step of melt compounding process with the addition of cross-linking agent and accelerators. The SWCNTs were dispersed uniformly, and a fine network was constructed in the matrix of the obtained IIR/SWCNTs nanocomposite with a low percolation threshold. With the concentration of SWCNTs as low as 2 phr, the IIR/SWCNTs nanocomposite received an electrical conductivity of 10−6∼10−3 S/cm, and a 71% improvement of tensile strength. By varying the loadings of SWCNTs in a certain range, the tensile strength, electrical conductivity, and dielectric property were found tunable. Besides, the nanocomposites also presented strain responsive specific resistance, excellent elongation (600–740%), and better heat resistance.


MRS Bulletin ◽  
2007 ◽  
Vol 32 (4) ◽  
pp. 348-353 ◽  
Author(s):  
Karen I. Winey ◽  
Takashi Kashiwagi ◽  
Minfang Mu

AbstractThe remarkable electrical and thermal conductivities of isolated carbon nanotubes have spurred worldwide interest in using nanotubes to enhance polymer properties. Electrical conductivity in nanotube/polymer composites is well described by percolation, where the presence of an interconnected nanotube network corresponds to a dramatic increase in electrical conductivity ranging from 10−5 S/cm to 1 S/cm. Given the high aspect ratios and small diameters of carbon nanotubes, percolation thresholds are often reported below 1 wt% although nanotube dispersion and alignment strongly influence this value. Increases in thermal conductivity are modest (∼3 times) because the inter facial thermal re sis tance between nanotubes is considerable and the thermal conductivity of nanotubes is only 104 greater than the polymer, which forces the matrix to contribute more toward the composite thermal conductivity, as compared to the contrast in electrical conductivity, >1014. The nanotube network is also valuable for improving flame-retardant efficiency by producing a protective nanotube residue. In this ar ticle, we highlight published research results that elucidate fundamental structure–property relationships pertaining to electrical, thermal, and/or flammability properties in numerous nanotube-containing polymer composites, so that specific applications can be targeted for future commercial success.


2015 ◽  
Vol 1101 ◽  
pp. 89-92
Author(s):  
K.V. Sreenivas Rao ◽  
S. Sanman

The remarkable high tensile strength and very high aspect ratio of carbon nanotubes make them valuable components for mechanically reinforced composite materials. In this study, Carbon Nanotube (CNT) reinforced aluminum matrix composites were prepared by simple stir casting route with different percentages of Carbon Nanotube reinforcement. The prepared nanocomposite specimens were subjected to evaluation of mechanical properties and microstructure. It was evident from the study that, as the weight fraction of nanotube in the matrix increases, the ultimate tensile strength, macro and micro-hardness also increases. The microstructures show clustering of the carbon nanotubes in the matrix. The difficulties experienced in uniform dispersion of Carbon Nanotube in the matrix to achieve optimum desired properties are discussed.


2017 ◽  
Vol 51 (20) ◽  
pp. 2899-2912 ◽  
Author(s):  
MK Hassanzadeh-Aghdam ◽  
R Ansari ◽  
A Darvizeh

A comprehensive investigation is carried out into the elastic behavior of carbon nanotube-reinforced polymer nanocomposites using two combined analytical micromechanical methods. A unit cell-based micromechanical method is developed to model the random distribution of carbon nanotubes within the polymer matrix. Also, the Eshelby method is used for modeling the random orientation state of carbon nanotubes within the matrix. Two fundamental aspects affecting the mechanical behavior of carbon nanotube/polymer nanocomposites, including the carbon nanotube waviness and the interphase formed due to the non-boned interaction between the carbon nanotube and the surrounding polymer, are considered in the unit cell method. Comparisons between the results of present method and experimental data reveal that for more realistic predictions, five important factors including, random orientation and random distribution of carbon nanotubes, interphase, waviness and transversely isotropic behavior of carbon nanotube should be considered in the modeling of carbon nanotube-reinforced polymer nanocomposites. The effects of volume fraction, number of waves and waviness factor of carbon nanotube as well as the type of random distribution of CNTs within the matrix on the elastic modulus of the polymer nanocomposites are studied.


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