scholarly journals Electromagnetic, Morphological, and Electrical Characterization of POMA/Carbon Nanotubes-Based Composites

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Simone de Souza Pinto ◽  
Mirabel Cerqueira Rezende
Keyword(s):  
Carbon Nanotubes ◽  
Epoxy Resin ◽  
Network Formation ◽  
Electrical Characterization ◽  
Resin Matrix ◽  
X Band ◽  
Ft Ir ◽  
Electrical Permittivity

This study involves the preparation of conducting composites based on poly(o-methoxyaniline) (POMA) and carbon nanotubes (CNT) and the evaluation of them as radar absorbing materials (RAM), in the frequency range of 8.2–12.4 GHz (X-band). The composites were obtained by synthesis in situ of POMA in the presence of CNT (0.1 and 0.5 wt% in relation to the o-methoxyaniline monomer). The resulting samples—POMA/CNT-0.1 wt% and POMA/CNT-0.5 wt%—were incorporated in an epoxy resin matrix in the proportion of 1 and 10 wt%. FT-IR analyses show that the POMA was successfully synthesized on the CNT surface. SEM analyses show that the synthesized POMA recovered all CNT surface. Electrical conductivity measurements show that the CNT contributed to increase the conductivity of POMA/CNT composites (1.5–6.7 S·cm−1) in relation to the neat POMA (5.4 × 10−1 S·cm−1). The electromagnetic characterization involved the measurements of complex parameters of electrical permittivity (ε) and magnetic permeability (µ), using a waveguide in the X-band. From these experimental data reflection loss (RL) simulations were performed for specimens with different thicknesses. The complex parameters show that the CNT in the composites increased ε and µ. These results are attributed to the CNT network formation into the composites. Simulated RL curves of neat POMA and POMA/CNT in epoxy resin show the preponderant influence of POMA on all RL curves. This behavior is attributed to the efficient CNT recovering by POMA. RL results show that the composite based on 10 wt% of POMA/CNT-0.5 wt% in epoxy resin (9 mm thickness) presents the best RL results (≈87% of attenuation at 12.4 GHz).

scholarly journals Morphological, electromagnetic and absorbing properties of pani/epoxy resin samples

2018 ◽  
Vol 1 (3) ◽  
Author(s):  
Simone Souza Pinto 1 ◽  
Rafaela Chinelatto Filipsen 1 ◽  
Newton Adriano Santos Gomes 2 ◽  
Carlos Vinícios Opelt 2 ◽  
Mirabel Cerqueira Rezende 1,2
Keyword(s):  
Epoxy Resin ◽  
Average Diameter ◽  
Incident Radiation ◽  
Resin Matrix ◽  
Specimen Thickness ◽  
X Band ◽  
Ft Ir ◽  
Electrical Permittivity ◽  
Granular Morphology ◽  
Attenuation Values

This work deals with the study of radar absorbing materials (RAM) based on conductive samples obtained with polyaniline (PAni) (5-20 wt%) inserted in epoxy resin matrix. SEM analyses show that the PAni presents granular morphology, with an average diameter of 5 µm, with structures evenly distributed. DRX and FT-IR analyses show that the PAni polymer was successfully obtained in its conductive form. Electrical permittivity and magnetic permeability measurements of PAni/epoxy samples were performed in the frequency range of 8.2 to 12.4 GHz (X-band). Microwave attenuation values showed that the PAni-20wt%/epoxy resin sample presented a maximum attenuation of -24 dB, i.e. ~99.6% attenuation of the incident radiation. It was also observed that the amount of attenuated energy varies according to the incident frequency and the specimen thickness.

FT-IR, SIMS and electrical characterization of Si3N4 thin films obtained from CVD, assisted by in situ electrical discharge

1993 ◽  
Vol 24 (4) ◽  
pp. 389-393
Author(s):  
B. Balland ◽  
R. Botton ◽  
M. Lemiti ◽  
J.C. Bureau ◽  
A. Glachant
Keyword(s):  
Thin Films ◽  
Electrical Discharge ◽  
Electrical Characterization ◽  
Ft Ir

scholarly journals Synthesis of Poly(methacrylic acid-co-butyl acrylate) Grafted onto Functionalized Carbon Nanotube Nanocomposites for Drug Delivery

Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 533 ◽  
Author(s):  
Josué A. Torres-Ávalos ◽  
Leonardo R. Cajero-Zul ◽  
Milton Vázquez-Lepe ◽  
Fernando A. López-Dellamary ◽  
Antonio Martínez-Richa ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Drug Delivery ◽  
Methacrylic Acid ◽  
Butyl Acrylate ◽  
Chemical Vapor ◽  
Vis Spectroscopy ◽  
Ir And Raman Spectroscopies ◽  
Ft Ir

Design of a smart drug delivery system is a topic of current interest. Under this perspective, polymer nanocomposites (PNs) of butyl acrylate (BA), methacrylic acid (MAA), and functionalized carbon nanotubes (CNTsf) were synthesized by in situ emulsion polymerization (IEP). Carbon nanotubes were synthesized by chemical vapor deposition (CVD) and purified with steam. Purified CNTs were analyzed by FE-SEM and HR-TEM. CNTsf contain acyl chloride groups attached to their surface. Purified and functionalized CNTs were studied by FT-IR and Raman spectroscopies. The synthesized nanocomposites were studied by XPS, 13C-NMR, and DSC. Anhydride groups link CNTsf to MAA–BA polymeric chains. The potentiality of the prepared nanocomposites, and of their pure polymer matrices to deliver hydrocortisone, was evaluated in vitro by UV–VIS spectroscopy. The relationship between the chemical structure of the synthesized nanocomposites, or their pure polymeric matrices, and their ability to release hydrocortisone was studied by FT-IR spectroscopy. The hydrocortisone release profile of some of the studied nanocomposites is driven by a change in the inter-associated to self-associated hydrogen bonds balance. The CNTsf used to prepare the studied nanocomposites act as hydrocortisone reservoirs.

Synthesis and Characterization of Poly(2,5-benzimidazole) (ABPBI) Grafted Carbon Nanotubes

2009 ◽  
Vol 1240 ◽  
Author(s):  
Ji-Ye Kang ◽  
Su-Mi Eo ◽  
Loon-Seng Tan ◽  
Jong-Beom Baek
Keyword(s):  
Carbon Nanotubes ◽  
Carbon Nanotube ◽  
Interfacial Adhesion ◽  
Synthesis And Characterization ◽  
Acylation Reaction ◽  
Single Walled Carbon Nanotube ◽  
Mechanical And Electrical Properties ◽  
Multi Walled Carbon Nanotube

AbstractSingle-walled carbon nanotube (SWCNT) and multi-walled carbon nanotube (MWCNT) were functionalized with 3,4-diaminobenzoic acid via “direct” Friedel-Crafts acylation reaction in PPA/P2O5 to afford ortho-diamino-functionalized SWCNT (DIF-SWCNT) and MWCNT (DIF-MWCNT). The resultant DIF-SWCNT and DIF-MWCNT showed improved solubility and dispersibility. To improve interfacial adhesion between CNT and polymer matrix, the grafting of ABPBI onto the surface of DIF-SWCNT (10 wt%) or DIF-MWCNT (10 wt%) was conducted by simple in-situ polymerization of AB monomer, 3,4-diaminobenzoic acid dihydrochloride, in PPA. The resultant ABPBI-g-MWCNT and ABPBI-g-SWCNT showed improved the mechanical and electrical properties.

Diffuse Reflectance FT-IR Characterization of Active Sites under Reaction Conditions: The Production of Oxygenates in the CO/H2 Reaction

1994 ◽  
Vol 48 (10) ◽  
pp. 1208-1212 ◽  
Author(s):  
J. J. Benítez ◽  
I. Carrizosa ◽  
J. A. Odriozola
Keyword(s):  
Infrared Spectra ◽  
Active Sites ◽  
Diffuse Reflectance ◽  
Reaction Conditions ◽  
In Situ Drifts ◽  
Ft Ir

The reactivity of a Lu2O3-promoted Rh/Al2O3 catalyst in the CO/H2 reaction is reported. Methane, heavier hydrocarbons, methanol, and ethanol are obtained. In situ DRIFTS has been employed to record the infrared spectra under the actual reaction conditions. The structure of the observed COads DRIFTS bands has been resolved into its components. The production of oxygenates (methanol and ethanol) has been correlated with the results of the deconvolution calculation. Specific sites for the production of methanol and ethanol in the CO/H2 reaction over a Rh,Lu2O3/Al2O3 catalyst are proposed.

scholarly journals In situ electrical characterization of palladium-based single electron transistors made by electromigration technique

AIP Advances ◽  
2014 ◽  
Vol 4 (11) ◽  
pp. 117126 ◽  
Author(s):  
L. Arzubiaga ◽  
F. Golmar ◽  
R. Llopis ◽  
F. Casanova ◽  
L. E. Hueso
Keyword(s):  
Electrical Characterization ◽  
Single Electron ◽  
Single Electron Transistors ◽  
Electron Transistors

In Situ Atomic Force Microscopy Tip-Induced Deformations and Raman Spectroscopy Characterization of Single-Wall Carbon Nanotubes

Nano Letters ◽  
2012 ◽  
Vol 12 (8) ◽  
pp. 4110-4116 ◽  
Author(s):  
P. T. Araujo ◽  
N. M. Barbosa Neto ◽  
H. Chacham ◽  
S. S. Carara ◽  
J. S. Soares ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Raman Spectroscopy ◽  
Atomic Force Microscopy ◽  
Single Wall Carbon Nanotubes ◽  
Single Wall Carbon ◽  
Force Microscopy ◽  
Atomic Force

Broadband Electrical Characterization of Multiwalled Carbon Nanotubes and Contacts

Nano Letters ◽  
2007 ◽  
Vol 7 (4) ◽  
pp. 1086-1090 ◽  
Author(s):  
Paul Rice ◽  
T. Mitch Wallis ◽  
Stephen E. Russek ◽  
Pavel Kabos
Keyword(s):  
Carbon Nanotubes ◽  
Multiwalled Carbon Nanotubes ◽  
Electrical Characterization ◽  
Multiwalled Carbon
Sign in / Sign up

Export Citation Format

Share Document