Synthesis and characterization of multi-walled carbon nanotubes modified with octadecylamine and polyethylene glycol

Salam, Mohamed Abdel; Burk, Robert

doi:10.1016/j.arabjc.2012.12.028

Cited by 95 publications

(54 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…13-0148, appeared. 41 The inset of the figure confirms the multiwalled structure of CNT. As seen, wall-thickness is about 7.06 nm and the inner diameter of the wall is 6.92 nm.…”

Section: Measurementssupporting

confidence: 53%

Characterization, optical, and nanoscale free volume properties of Na‐CMC/PAM/CNT nanocomposites

Awad

El‐Gamal

Sayed

et al. 2019

Polymers for Advanced Techs

View full text Add to dashboard Cite

Polyblend and nanocomposite films of sodium salt of carboxymethylcellulose (Na‐CMC)/polyacrylamide (PAM) and Na‐CMC/PAM modified with carbon nanotubes (CNT) were synthesized by the solution casting technique. The effect of PAM and CNT loading on the structural, optical, and nanoscale free volume properties of Na‐CMC was studied. X‐ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy exhibited the existence of strong interactions between Na‐CMC and PAM and the non‐destructive effect of CNT on Na‐CMC/PAM structure. The HR‐TEM revealed the multi‐walled structure of CNT with a 7.06‐nm wall thickness and a 6.92‐nm wall inner diameter. Positron annihilation lifetime spectroscopy (PALS) was done, in a vacuum and at 30°C to 200°C, to investigate the nanoscale free volume properties by using a conventional fast‐fast coincidence spectrometer. It was found that the o‐Ps lifetime (τ3) and free volume (Vh) increase with increasing CNT percentage in the Na‐CMC/PAM blend. The distribution of the o‐Ps lifetime was broadened with increasing CNT ratios. Furthermore, the glass transition temperature (Tg) increases with increasing loads of CNT. For the first time, a correlation was done between Urbach energy (EU) and Vh. Finally, the results were represented and discussed in the frame of free volume properties. Optical measurements showed that the transmittance T% of Na‐CMC/PAM was 91.12% and decreased to 68.42% and 36.45% after loading with 1.0 and 2.0 wt % CNT. In addition, the blend shows higher insulating properties compared with the individual polymers. The CNT incorporation reduces the band gap significantly and increases the EU in the films.

show abstract

“…13-0148, appeared. 41 The inset of the figure confirms the multiwalled structure of CNT. As seen, wall-thickness is about 7.06 nm and the inner diameter of the wall is 6.92 nm.…”

Section: Measurementssupporting

confidence: 53%

Characterization, optical, and nanoscale free volume properties of Na‐CMC/PAM/CNT nanocomposites

Awad

El‐Gamal

Sayed

et al. 2019

Polymers for Advanced Techs

View full text Add to dashboard Cite

show abstract

“…The stretching vibration of C-O groups in the alginate polysaccharide was confirmed at 1052 cm −1 , 1026 cm −1 and 1020 cm −1 for A, A/γ-Fe 2 O 3 and A/γ-Fe 2 O 3 /f-CNT, respectively. Finally the characteristic Fe-O elongation vibration was observed at 622 cm −1 in γ-Fe 2 O 3 and A/γ-Fe 2 O 3 spectra and at 618 in A/γ-Fe 2 O 3 /f-CNT [37,38]. The thermal stability of the materials was evaluated by thermogravimetric analysis.…”

Section: Characterization Of the Tested Adsorbentsmentioning

confidence: 99%

Effective Adsorption of Methylene Blue dye onto Magnetic Nanocomposites. Modeling and Reuse Studies

et al. 2019

View full text Add to dashboard Cite

In the present study, new adsorbent beads of alginate (A)/maghemite nanoparticles (γ-Fe2O3)/functionalized multiwalled carbon nanotubes (f-CNT) were prepared and characterized by several techniques, e.g., N2 adsorption-desorption isotherms, Fourier transformed infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA/DTG), scanning electron microscopy (SEM), and vibrating sample magnetometry (VSM) and further tested for the adsorption of the dye methylene blue (MB) from water. The beads (A/γ-Fe2O3/f-CNT) presented a relatively low BET specific surface area value of 59 m2g−1. The magnetization saturation values of A/γ-Fe2O3/f-CNT beads determined at 295 K was equal to 27.16 emu g−1, indicating a magnetic character. The time needed to attain the equilibrium of MB adsorption onto the beads was estimated within 48 h. Thus, several kinetic and isotherm equation models were used to fit the kinetic and equilibrium experimental results. The number of adsorbed MB molecules per active site, the anchorage number, the receptor sites density, the adsorbed quantity at saturation, the concentration at half saturation and the molar adsorption energy were quantified using the monolayer model. The calculated negative ΔG0 and positive ΔH0 values suggested the spontaneous and endothermic nature of the adsorption process. In addition, A/γ-Fe2O3/f-CNT composites can be used at least for six times maintaining their significant adsorptive performance and could be easily separated by using a magnet from water after treatment.

show abstract

“…This phenomenon was also reported by Johnson et al for the coupling of TOCNs with octadecylamine (ODA) through ionic bonds. No thermal improvement of the ODA‐modified TOCNs was achieved because of the low thermal degradation temperature of ODA (<200 °C) . While the TOCN‐COOH/3AP sample showed a T max value identical to that of the unmodified TOCN‐COOH (300 °C), the maximal degradation temperature of the TOCN‐COOH/22AE sample was slightly increased, by 30 °C.…”

Section: Resultsmentioning

confidence: 98%

Optimization of preparation of thermally stable cellulose nanofibrils via heat‐induced conversion of ionic bonds to amide bonds

Lavoine

Bras

Saito

et al. 2017

J. Polym. Sci. Part A: Polym. Chem.

View full text Add to dashboard Cite

Improving the thermal stability of nanocelluloses is important for practical applications such as melt compounded nanocellulose‐reinforced polymer composites and flexible substrates for nanocellulose‐containing electronic devices. Here, we report optimum conditions for a straightforward surface modification strategy for improving the thermal stability of 2,2,6,6‐tetramethypiperidine‐1‐oxyl (TEMPO)‐oxidized cellulose nanofibrils (TOCNs); the heat‐induced conversion of TOCN alkyl ammonium carboxylates to amides. Different amine‐terminated compounds (R‐NH2) were grafted onto the surface of TOCNs under aqueous conditions. The influences of R‐NH2 molecular weight, R‐NH2/TOCN‐COOH molar ratio, and thermal stability of R‐NH2 on the properties of the grafted TOCN films were investigated through infrared spectroscopy and thermogravimetric analysis. For maximum thermal improvement of up to 90 °C, complete ionic bonding of TOCN carboxy groups with R‐NH2 was required, as well as proper selection of the R‐NH2 compound. A controlled heating process was also needed to achieve effective ionic‐to‐amide bond conversion. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 1750–1756

show abstract

Synthesis and characterization of multi-walled carbon nanotubes modified with octadecylamine and polyethylene glycol

Cited by 95 publications

References 33 publications

Characterization, optical, and nanoscale free volume properties of Na‐CMC/PAM/CNT nanocomposites

Characterization, optical, and nanoscale free volume properties of Na‐CMC/PAM/CNT nanocomposites

Effective Adsorption of Methylene Blue dye onto Magnetic Nanocomposites. Modeling and Reuse Studies

Optimization of preparation of thermally stable cellulose nanofibrils via heat‐induced conversion of ionic bonds to amide bonds

Contact Info

Product

Resources

About