Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
. 2013 Nov 19:2013:703708.
doi: 10.1155/2013/703708.

Cure kinetics of epoxy nanocomposites affected by MWCNTs functionalization: a review

Mohammad Reza Saeb  1 , Ehsan Bakhshandeh  1 , Hossein Ali Khonakdar  2 , Edith Mäder  3 , Christina Scheffler  3 , Gert Heinrich  4
Affiliations
Review

Cure kinetics of epoxy nanocomposites affected by MWCNTs functionalization: a review

Mohammad Reza Saeb et al. ScientificWorldJournal. .

Abstract

The current paper provides an overview to emphasize the role of functionalization of multiwalled carbon nanotubes (MWCNTs) in manipulating cure kinetics of epoxy nanocomposites, which itself determines ultimate properties of the resulting compound. In this regard, the most commonly used functionalization schemes, that is, carboxylation and amidation, are thoroughly surveyed to highlight the role of functionalized nanotubes in controlling the rate of autocatalytic and vitrification kinetics. The current literature elucidates that the mechanism of curing in epoxy/MWCNTs nanocomposites remains almost unaffected by the functionalization of carbon nanotubes. On the other hand, early stage facilitation of autocatalytic reactions in the presence of MWCNTs bearing amine groups has been addressed by several researchers. When carboxylated nanotubes were used to modify MWCNTs, the rate of such reactions diminished as a consequence of heterogeneous dispersion within the epoxy matrix. At later stages of curing, however, the prolonged vitrification was seen to be dominant. Thus, the type of functional groups covalently located on the surface of MWCNTs directly affects the degree of polymer-nanotube interaction followed by enhancement of curing reaction. Our survey demonstrated that most widespread efforts ever made to represent multifarious surface-treated MWCNTs have not been directed towards preparation of epoxy nanocomposites, but they could result in property synergism.

PubMed Disclaimer

Figures

Scheme 1
Scheme 1
Oxirane ring opening via the nucleophilic addition reaction in an epoxide system.
Scheme 2
Scheme 2
Mechanism of curing epoxy resins with amine hardeners.
Scheme 3
Scheme 3
Illustrating the mechanism of etherification reaction.
Scheme 4
Scheme 4
Mechanism of Lewis acid-catalyzed curing of epoxy by alcohol.
Scheme 5
Scheme 5
Mechanism of curing epoxy resins with anhydride hardeners.
Figure 1
Figure 1
Conversion as a function of temperature at heating rate of 20°C/min for the neat epoxy and MWCNTs-filled epoxy systems. After [13].
Figure 2
Figure 2
The reaction rate and extent of reaction of TGDDM/DDS epoxy and its nanocomposites as a function of time at 180°C. After [19].
Figure 3
Figure 3
Curve of diffusion control function, f d(α), against extent of reaction for 1 wt% MWCNTs/epoxy nanocomposites: the effect of curing temperature. After [19].
Figure 4
Figure 4
Plots of activation energy against α of neat epoxy, untreated systems containing 1, 3, and 5 wt% of MWCNTs (N1, N3, N5), and functionalized systems containing 1, 3, and 5 wt% of COOH-MWCNTs (C1, C3, C5). Dotted lines are given for showing the tendency. After [21].
Figure 5
Figure 5
Isothermal DSC thermograms of neat EPON828, 1 wt% F-MWCNTs/epoxy and COOH-MWCNT/epoxy, nanocomposites at 120°C. After [15].
Figure 6
Figure 6
Dynamic DSC thermograms of neat epoxy and its raw MWCNTs nanocomposites (a); neat epoxy and its amino-functionalized MWCNTs nanocomposites (b). After [53].
Figure 7
Figure 7
DSC thermograms at 20°C/min of neat epoxy (C 0), 0.5 wt% as-received MWCNTs/epoxy nanocomposites (C 1), and 0.5 wt% amine-modified MWCNTs/epoxy nanocomposites (C 2). Dotted lines are given for showing the tendency. After [10].
Figure 8
Figure 8
Plots of activation energy of neat epoxy (C 0), 0.5 wt% as-received MWCNTs/epoxy nanocomposites (C 1), and 0.5 wt% amine-modified MWCNTs/epoxy nanocomposites (C 2) against degree of cure obtained by isoconversional kinetic model. After [10].
Figure 9
Figure 9
Dynamic DCS thermograms of stoichiometric mixtures (r = 1) with different amino-functionalized CNT contents. After [14].
Scheme 6
Scheme 6
Schematic representation of the reaction between functionalized MWCNTs with DGEBA resin: (a) fluorinated CNT; (b) carboxylated CNT.
Scheme 7
Scheme 7
The procedures used for functionalization of MWCNTs by Shen et al.
See this image and copyright information in PMC

References

    1. Iijima S. Helical microtubules of graphitic carbon. Nature. 1991;354(6348):56–58.
    1. Ajayan PM, Stephan O, Colliex C, Trauth D. Aligned carbon nanotube arrays formed by cutting a polymer resin-nanotube composite. Science. 1994;265(5176):1212–1214. - PubMed
    1. Lee SH, Cho E, Jeon SH, Youn JR. Rheological and electrical properties of polypropylene composites containing functionalized multi-walled carbon nanotubes and compatibilizers. Carbon. 2007;45(14):2810–2822.
    1. Du F, Scogna RC, Zhou W, Brand S, Fischer JE, Winey KI. Nanotube networks in polymer nanocomposites: rheology and electrical conductivity. Macromolecules. 2004;37(24):9048–9055.
    1. Vega JF, Martínez-Salazar J, Trujillo M, et al. Rheology, processing, tensile properties, and crystallization of polyethylene/carbon nanotube nanocomposites. Macromolecules. 2009;42(13):4719–4727.

Substances

LinkOut - more resources