Fabrication and Mechanical Properties of MWNTs/Phenolic Nanocomposites

2006 ◽  
Vol 505-507 ◽  
pp. 121-126 ◽  
Author(s):  
Meng Kao Yeh ◽  
Nyan Hwa Tai ◽  
Yan Jyun Lin

The multi-walled carbon nanotubes (MWNTs) were added into the phenolic resin to fabricate MWNTs/phenolic nanocomposites. The pressure and temperature were applied to cure MWNTs/phenolic compound by hot press method, then followed by a post curing process. The results showed that post-curing of the nanocomposites specimen is necessary for better mechanical properties. The temperature used for post curing should be higher than the curing temperature. The higher curing pressure improved the Young’s modulus of the nanocomposites. The tensile failure morphologies of MWNTs/phenolic nanocomposites were examined using field emission scanning electron microscope (FESEM) to evaluate the effects of manufacturing processes on the mechanical properties of MWNTs/phenolic nanocomposites.

Nanomaterials ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 2503
Author(s):  
Liyang Cao ◽  
Yongsheng Liu ◽  
Jing Wang ◽  
Yu Pan ◽  
Yunhai Zhang ◽  
...  

The applications of pure multi-walled carbon nanotubes (MWCNTs) buckypapers are still limited due to their unavoidable micro/nano-sized pores structures. In this work, polyvinyl alcohol (PVA) was added to a uniform MWCNTs suspension to form MWCNT/PVA buckypapers by vacuum infiltration combined with a hot press method. The results showed an improvement in the thermal, electrical, and electromagnetic interference (EMI) shielding properties due to the formation of dense MWCNTs networks. The thermal and electrical properties rose from 1.394 W/m·k to 2.473 W/m·k and 463.5 S/m to 714.3 S/m, respectively. The EMI performance reached 27.08 dB. On the other hand, ABAQUS finite element software was used to simulate the coupled temperature-displacement performance. The electronic component module with buckypapers revealed a homogeneous temperature and thermal stress distribution. In sum, the proposed method looks promising for the easy preparation of multi-functional nanocomposites at low-cost.


2007 ◽  
Vol 334-335 ◽  
pp. 713-716 ◽  
Author(s):  
Meng Kao Yeh ◽  
Nyan Hwa Tai ◽  
Yan Jyun Lin

The multi-walled carbon nanotubes (MWNTs) and carbon fibers (CFs) were added to the phenolic resin to fabricate MWNTs/phenolic, MWNTs/CFs/phenolic nanocomposites and CFs/phenolic composites by hot press method. The differential scanning calorimetry (DSC) test was performed for the above-mentioned three kinds of composites. The valley points on the slope of endothermic responses correspond to the glass transition temperatures of the composites. The MWNTs/phenolic nanocomposites had the lowest glass transition temperature among the three kinds of composites discussed, which indicated a better thermal conductivity property of MWNTs. Phenolic-based composites reinforced by different weight percentages of MWNTs and CFs were also investigated. The tensile failure morphologies of nanocomposite specimens were examined using a scanning electron microscope to evaluate the possible effects on the glass transition temperature of nanocomposites..


2007 ◽  
Vol 1006 ◽  
Author(s):  
Renato Amaral Minamisawa ◽  
Bopha Chhay ◽  
Daryush ILA

AbstractThe reported electromagnetic properties of carbon nanotubes (CNT) make them a promising material for nanoelectronic applications [1,2]. Addition of CNT has recently been shown to enhance mechanical properties of phenolic-resin polymers [3]. We are attempting to control the electrical transport behavior of phenolic-based polymers doped with CNT as a function of the different nanopowder concentration added to the polymer. In that regard, we developed a technique to obtain a material with homogenous dispersion of nanopowders, an important factor that influences the transport behavior. The chemical structure characterization was also evaluated using optical techniques.


2019 ◽  
Vol 54 (14) ◽  
pp. 1847-1861
Author(s):  
Alireza Bagherzade ◽  
Masoud Jamshidi

In this study, multi-walled carbon nanotubes (MWCNTs) were functionalized by both sulfuric/nitric acids and amino acids to form COOH and NH2/COOH/OH groups on their surface, respectively. The functionalized MWCNTs were characterized by Fourier Transform Infrared Spectroscopy, titration test, thermal gravimetric analysis, and solvent stability test. The results revealed that in each method, the functional groups were successfully attached to the surface of nanotubes. Acid treatment grafted more oxygen-containing groups compared to commercial carboxylated MWCNTs. The amino acid functionalized MWCNTs indicated improved stability in different solvents compared to raw and acid treated MWCNTs. These functionalized MWCNTs were incorporated into epoxy resin and the properties of the nanocomposites were evaluated by scanning electron microscopy, tensile test, dynamic mechanical thermal analysis, differential scanning calorimetry, and thermogravimetric analysis. The morphology of the nanocomposites revealed that acid and amino acid treated samples had better interaction with the epoxy resin. Compared to epoxy sample contained raw MWCNT (control) and commercial carboxylated MWCNTs, the addition of functionalized MWCNTs to the epoxy resin improved the tensile strength by 39% and 25% (for acid treated) and 46% and 33% (for amino acid treated), respectively. The best tensile properties for acid and amino acid treated samples were reached by MWCNTs acid treated at 110℃ for 15 min and MWCNTs treated in a 50 g/L aqueous solution of amino acid, respectively. Storage modulus of the epoxy samples which contained acid and amino acid treated MWCNTs were 1560 and 1900 MPa, respectively. The glass rubber transition temperature ( Tg) of the epoxy samples containing acid and amino acid treated nanotubes were increased by 1.1℃ and 5.9℃, respectively, compared to the control sample. Therefore, based on these mechanical properties, the epoxy samples containing nanotubes functionalized by amino acid exhibited the highest performance in the epoxy nanocomposite. Incorporating acid and amino acid treated MWCNTs accelerated the curing process of epoxy where the curing temperature decreased by 9.1℃ and 13.3℃, respectively. Because of the reaction between amine groups grafted on MWCNTs in the amino acid treatment and epoxide groups of the epoxy resin, this acceleration was more significant in the case of amino acid sample. Note that addition of functionalized MWCNTs to epoxy resin did not lead to increased thermal stability.


2021 ◽  
pp. 095400832199209
Author(s):  
Hermawan Judawisastra ◽  
Christian Harito ◽  
Dika Anindyajati ◽  
Hengky Purnama ◽  
Akbar Hanif Dawam Abdullah

The effects of composite fabrication, such as pre-curing, curing temperature, and cooling rate, were studied. In this work, the pre-curing was defined as heat treatment of Multi-Walled Carbon Nanotubes (MWNCTs) with Diglycidyl Ether of Bisphenol A (DGEBA) epoxy resin. Acid purified MWCNTs were characterized by Raman spectroscopy and Fourier Transform Infrared Spectroscopy (FTIR). The pre-curing facilitated bonding between MWCNTs and epoxy via the oxirane ring of DGEBA, which accelerated the curing process of epoxy and increased mechanical properties. The elevated curing temperature on the pre-cured sample further improved the composite’s mechanical properties by increasing interfacial bonding due to cross-linking. The rapid cooling using liquid nitrogen during pre-curing treatment prevented re-agglomeration of MWCNTs, showing smaller agglomerates and improving the mechanical properties. Agglomeration was characterized by scanning electron microscopy, while the bonding between MWCNTs and epoxy was examined by the length of fibre pull-out on the fracture surface. Tensile testing was deployed for mechanical properties characterization. The degree of cure was determined by FTIR and Differential Thermal Analysis (DTA).


2021 ◽  
Vol 3 (6) ◽  
Author(s):  
Seyed Ali Mirsalehi ◽  
Amir Ali Youzbashi ◽  
Amjad Sazgar

AbstractIn this study, epoxy hybrid nanocomposites reinforced by carbon fibers (CFs) were fabricated by a filament winding. To improve out-of-plane (transverse) mechanical properties, 0.5 and 1.0 Wt.% multi-walled carbon nanotubes (MWCNTs) were embedded into epoxy/CF composites. The MWCNTs were well dispersed into the epoxy resin without using any additives. The transverse mechanical properties of epoxy/MWCNT/CF hybrid nanocomposites were evaluated by the tensile test in the vertical direction to the CFs (90º tensile) and flexural tests. The fracture surfaces of composites were studied by scanning electron microscopy (SEM). The SEM observations showed that the bridging of the MWCNTs is one of the mechanisms of transverse mechanical properties enhancement in the epoxy/MWCNT/CF composites. The results of the 90º tensile test proved that the tensile strength and elongation at break of nanocomposite with 1.0 Wt.% MWCNTs improved up to 53% and 50% in comparison with epoxy/CF laminate composite, respectively. Furthermore, the flexural strength, secant modulus, and elongation of epoxy/1.0 Wt.% MWCNT/CF hybrid nanocomposite increased 15%, 7%, and 9% compared to epoxy/CF laminate composite, respectively.


Sign in / Sign up

Export Citation Format

Share Document