Hybrid Multiwalled Carbon Nanotubes/Minerals as Potential Fillers for Polymer Composites

2012 ◽  
Vol 620 ◽  
pp. 236-240 ◽  
Author(s):  
Muhammad Helmi Abdul Kudus ◽  
Md Akil Hazizan ◽  
Siti Shuhadah M. Saleh

Minerals are always used as filler material in polymer composite application purposely to reduce the price. In order to optimize the use of mineral fillers instead of price reduction, there were several approaches that have been done such as surface treatment, finding suitable coupling agent, and etc. The study on hybridization of minerals with carbon nanotubes (CNT) are rare to be found. CNT has received great attention from researchers due to their superior properties to be used in many applications. Hybridizing CNT with minerals proposes potential fillers for polymer composite. In this study, chemical vapor deposition (CVD) technique was used to synthesize the CNT-minerals hybrid compound. A mixture of CH4/N2was used as the carbon source and nickel as the metal catalyst for the growth of CNT hybrid compound. Three different types of minerals were used namely talc, muscovite and CaCO3are used to synthesize the MWCNT-talc, MWCNT-muscovite and MWCNT-CaCO3hybrid compound. In short, the process involved precipitation of mineral filler with nickel salt. The process was followed by calcinations and reduction of the catalyst, and methane decomposition. The produced hybrid compounds were then analyzed.

2004 ◽  
Vol 837 ◽  
Author(s):  
Yong-Won Lee ◽  
Rohit Deshpande ◽  
Anne C. Dillon ◽  
Michael J. Hebe ◽  
Hongjie Dai ◽  
...  

ABSTRACTMultiwalled carbon nanotubes (MWNTs) were continuously synthesized by hot wire chemical vapor deposition (HWCVD) using a methane source catalyzed by metal-organic ferrocene. The microstructure of the MWNTs and the catalyst particles were subsequently characterized with transmission electron microscopy which identified three different phases, i.e., bcc α-Fe, fcc γ-Fe and orthorhombic Fe3C. The hydrogen storage capacity of MWNTs was determined with temperature-programmed desorption (TPD) technique. Hydrogen adsorption at near ambient conditions was observed only in as-synthesized MWNTs containing iron particles and was dramatically increased after hydrogen reducing treatment. Possible adsorption mechanism was also discussed.


2002 ◽  
Vol 106 (22) ◽  
pp. 5629-5635 ◽  
Author(s):  
Lance Delzeit ◽  
Cattien V. Nguyen ◽  
Bin Chen ◽  
Ramsey Stevens ◽  
Alan Cassell ◽  
...  

2000 ◽  
Vol 6 (S2) ◽  
pp. 40-41
Author(s):  
D. Qian ◽  
E. C. Dickey ◽  
R. Andrews ◽  
T. Rantell ◽  
B. Safadi

Carbon nanotubes (NTs) have novel electronic properties and exceptionally high Young's moduli on the order of TPa. so NTs have potential applications in advanced composite materials such as conductive polymers, electromagnetic-radio frequency interference (EMI/RFI) shielding material and opto-electronic materials. The utility of the nanotubes in composite applications depends strongly on the ability to disperse the NTs homogeneously throughout the matrix without destroying the integrity of the NTs. Furthermore, interfacial bonding between the NT and matrix is necessary to achieve load transfer across the interface, which is desirable for improving the mechanical properties of polymer composites.In this work, aligned multiwalled carbon nanotubes (MWNTs) produced by continuous chemical vapor deposition (CVD) (see Fig.l), were homogeneously dispersed in polystyrene (PS) matrices by a simple solution-evaporation method. Using this procedure, we made uniform MWNT-PS composite films ∼0.4mm thick for ex-situ mechanical tensile test and very thin films, ∼100nm, for in-situ TEM tests, as shown in Fig.2.


2003 ◽  
Vol 800 ◽  
Author(s):  
Nam Seo Kim ◽  
Seung Yong Bae ◽  
Jeunghee Park

ABSTRACTWe report the catalytic effect on the synthesis of multiwalled carbon nanotubes (CNTs). The CNTs were grown vertically aligned on the iron (Fe), cobalt (Co), and nickel (Ni) catalytic nanoparticles deposited on alumina substrates by thermal chemical vapor deposition (CVD) of acetylene in the temperature range 900–1000 °C. We also synthesized them on the silicon oxide substrates by pyrolyzing iron phthalocyanine (FePc), cobalt phthalocyanine (CoPc), and nickel phthalocyanine (NiPc) at 700–1000 °C. In both syntheses, the CNTs grown using Fe exhibit about 2 times higher growth rate than those using Co and Ni. As the temperature rises from 700 to 1000 °C, the growth rate of CNTs increases by a factor of 45. The Arrhenius plot of growth rates provides the activation energy 30 ± 3 kcal/mol for all three catalysts, which is similar with the diffusion energy of carbon in bulk metal. It suggests that the bulk diffusion of carbon would play a decisive role in the growth of CNTs. The diameter of CNTs is in the range of 20–100 nm, showing an increase with the temperature. As the diameter is below 30 nm, the CNTs usually exhibit a cylindrical structure. The CNTs were intrinsically doped with the nitrogen content 2–6 atomic%. The degree of crystalline perfection of the graphitic sheets increases with the temperature, but depends on the catalyst and the nitrogen content. The graphitic sheets of CNTs grown using Fe are better crystalline than those grown using Co and Ni. As the nitrogen content increases, the degree of crystalline perfection decreases and the structure becomes the bamboolike structure probably due to a release of strains.


Author(s):  
Samuele Porro ◽  
Simone Musso ◽  
Massimo Rovere ◽  
Mauro Giorcelli ◽  
Angelica Chiodoni ◽  
...  

We report a study on a thermal chemical vapor deposition (CVD) system optimized for the growth of well packed and vertically aligned carbon nanotubes (CNTs) on uncoated silicon substrates. The process of synthesis involves the co-evaporation of a carbon precursor and a metal catalyst in a nitrogen atmosphere inside a high temperature furnace. Beside the formation of CNTs, depending in particular on the deposition temperature, other carbon structures can be deposited, such as nanographite. We show the growth results analyzed by different characterization techniques (electron microscopy, porosity and thermal stability investigations, micro-Raman spectroscopy). In addition, we report an investigation on the development of secondary transversal vortex flows caused by the effects of distribution of temperatures inside the growth system, in order to correlate them with the growth results.


Author(s):  
K. P. Yung ◽  
R. Y. J. Tay ◽  
J. Wei ◽  
B. K. Tay

Due to their extraordinary electrical, thermal and mechanical properties, carbon nanotubes (CNTs) have been foreseen as potential materials for electronics devices in the future. To integrate CNTs in electronic applications, CNTs would need to be deposited on different types of Si substrate. In this study, CNTs were grown on Ni catalyst layer with four types of substrates, namely Si, n++ Si, p++ Si and SiO2, using Plasma Enhanced Chemical Vapor Deposition (PECVD). The morphology and microstructure of the CNT films were analyzed by scanning electron microscopy (SEM) and Raman spectroscope. It was found that the type of Si substrate has significant effects on CNT growing characteristics. The possible mechanisms for the observed results are proposed. These findings add significant reference value to select deposition conditions suitable for deposition of CNTs on different types of Si substrate.


2019 ◽  
Vol 48 (29) ◽  
pp. 11018-11033 ◽  
Author(s):  
Gabriela Mera ◽  
Peter Kroll ◽  
Ilia Ponomarev ◽  
Jiewei Chen ◽  
Koji Morita ◽  
...  

Bamboo-like MWCNTs in a mesoporous silica matrix are synthesized by a simple metal-catalyst-free single-source precursor approach.


Author(s):  
Yung J. Jung ◽  
Laila Jaber-Ansari ◽  
Xugang Xiong ◽  
Sinan Mu¨ftu¨ ◽  
Ahmed Busnaina ◽  
...  

We will present a method to fabricate a new class of hybrid composite structures based on highly organized multiwalled carbon nanotube (MWNT) and singlewalled carbon nanotube (SWNT) network architectures and a polydimethylsiloxane (PDMS) matrix for the prototype high performance flexible systems which could be used for many daily-use applications. To build 1–3 dimensional highly organized network architectures with carbon nanotubes (both MWNT and SWNT) in macro/micro/nanoscale we used various nanotube assembly processes such as selective growth of carbon nanotubes using chemical vapor deposition (CVD) and self-assembly of nanotubes on the patterned trenches through solution evaporation with dip coating. Then these vertically or horizontally aligned and assembled nanotube architectures and networks are transferred in PDMS matrix using casting process thereby creating highly organized carbon nanotube based flexible composite structures. The PDMS matrix undergoes excellent conformal filling within the dense nanotube network, giving rise to extremely flexible conducting structures with unique electromechanical properties. We will demonstrate its robustness under large stress conditions, under which the composite is found to retain its conducting nature. We will also demonstrate that these structures can be directly utilized as flexible field-emission devices. Our devices show some of the best field enhancement factors and turn-on electric fields reported so far.


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