scholarly journals A Comparative Study of Polypyrrole and Ag/Polypyrrole Hybrid Nanocomposites as Sensitive Material Used for New Dry Polarizable Bioimpedance Sensors

2021 ◽  
Vol 11 (9) ◽  
pp. 4168
Author(s):  
Gabriela Telipan ◽  
Lucian Pîslaru-Dănescu ◽  
Eduard-Marius Lungulescu ◽  
Ioana Ion ◽  
Virgil Marinescu
Keyword(s):  
Hybrid Composites ◽  
Hydraulic Press ◽  
Hybrid Nanocomposites ◽  
Colloid Solution ◽  
Frequency Range ◽  
Ag Nps ◽  
Raman Spectrometry ◽  
Sensitive Material ◽  
Skin Preparation ◽  
Structural Characterisation

Three types of dry polarizable electric bioimpedance sensor for skin bioimpedance monitoring without skin preparation have been developed. The sensitive materials as a component of these sensors are the conductive polypyrrole and hybrid nanocomposite polypyrrole-Ag, with 10% and 20% Ag incorporated in the polypyrrole matrix. The hybrid nanocomposites Ag nanoparticles (NPs)/polypyrrole were obtained by introducing the colloid solution of Ag NPs in pyrrole solution, followed by polymerisation, and calculated for 10% and 20% of monomer’s mass. The structural characterisation and morphological analysis of these sensitive materials were carried-out by Raman spectrometry, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. In making the electrodes, the technique of pressing powders of polypyrrole and hybrid composites Ag NPs/polypyrrole in a hydraulic press was used in the form of a disk. The electric bioimpedance performance of sensors was investigated using a two-point method in the frequency range of 1–300 kHz, at a voltage of 2 Vpeak-peak, on six human subjects, three men and three women. For these three bioimpedance sensors, it was found that the electric bioimpedance of the skin decreases across the frequency range and shows good linearity of the impedance-frequency curve on the range frequency of interest in bioimpedance measurements.

scholarly journals Microwave Absorption Properties of Unripe Plantain Husk, Polycaprolactone and Charcoal Powder Hybrid Nanocomposites Using Numerical Simulation at X-Band Frequency

2021 ◽  
Vol 1 (2) ◽  
pp. 1-6
Author(s):  
A Yakubu
Keyword(s):  
Dielectric Constant ◽  
Microwave Absorption ◽  
Hybrid Composites ◽  
Average Particle Size ◽  
Hybrid Nanocomposites ◽  
Mean Deviation ◽  
Average Particle ◽  
Shielding Effectiveness ◽  
Frequency Range ◽  
Band Frequency

Single bulk materials have lesser advantages compared to nano materials in the area of mechanical, electrical, dielectric, optical and thermal properties enhancement of polymer and hybrid of bio-composites. In this work, charcoal (CH), unripe plantain husk (UPH), and polycaprolactone (PCL) based microwave absorber were synthesized using both mechanical alloy and melt blend techniques, respectively. Different percentages of the prepared charcoal nanoparticles was introduced into the hybrid composites to study the effect on dielectric properties, shielding effectiveness, reflection loss and structural morphology in the frequency range of 8–12 GHz.. Findings showed that the sample with the highest amount of charcoal percentage had the best shielding effectiveness and dielectric constant. The value of dielectric constant gradually increased from 3.06 to 5.45 at the frequency range measured. The charcoal average particle size was estimated to be 21.42 nm using TEM analysis while the mean deviation of surface roughness ranged from 5.45 to 25.56 nm using atomic force microscope. The highest shielding effectiveness of the hybrid composites was obtained for the 30 wt% nano charcoal content with a value of -48.78 dB at 10 GHz. The complete dispersion and interaction of the charcoal with the PCL and UPH enhanced the dielectric constant, loss factor, hence making it potent in microwave absorption, shielding and radar applications.

Influence of Multiwall Carbon Nanotube on mechanical and wear properties of Copper – Iron composite

2020 ◽  
Vol 17 (1) ◽  
pp. 7570-7576 ◽  
Author(s):  
H. Sh. Hammood ◽  
S. S. Irhayyim ◽  
A. Y. Awad ◽  
H. A. Abdulhadi
Keyword(s):  
Carbon Nanotubes ◽  
Volume Fraction ◽  
Hybrid Composites ◽  
Hydraulic Press ◽  
Dry Sliding Wear ◽  
Multiwall Carbon Nanotube ◽  
Wear Properties ◽  
Sem Images ◽  
Wear Rates ◽  
Multiwall Carbon

Multiwall Carbon nanotubes (MWCNTs) are frequently attractive due to their novel physical and chemical characteristics, as well as their larger aspect ratio and higher conductivity. Therefore, MWCNTs can allow tremendous possibilities for the improvement of the necessarily unique composite materials system. The present work deals with the fabrication of Cu-Fe/CNTs hybrid composites manufactured by powder metallurgy techniques. Copper powder with 10 vol. % of iron powder and different volume fractions of Multi-Wall Carbon Nanotubes (MWCNTs) were mixed to get hybrid composites. The hybrid composites were fabricated by adding 0.3, 0.6, 0.9, and 1.2 vol.% of MWCNTs to Cu- 10% Fe mixture using a mechanical mixer. The samples were compressed under a load of 700 MPa using a hydraulic press to compact the samples. Sintering was done at 900°C for 2 h at 5ºC/min heating rate. The microscopic structure was studied using a Scanning Electron Microscope (SEM). The effect of CNTs on the mechanical and wear properties, such as micro-hardness, dry sliding wear, density, and porosity were studied in detail. The wear tests were carried out at a fixed time of 20 minutes while the applied loads were varied (5, 10, 15, and 20 N). SEM images revealed that CNTs were uniformly distributed with relative agglomeration within the Cu/Fe matrix. The results showed that the hardness, density, and wear rates decreased while the percentage of porosity increased with increasing the CNT volume fraction. Furthermore, the wear rate for all the CNTs contents increased with the applied load.

scholarly journals Electromagnetic Interference Shielding and Physical-Mechanical Characteristics of Rubber Composites Filled with Manganese-Zinc Ferrite and Carbon Black

Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 616
Author(s):  
Ján Kruželák ◽  
Andrea Kvasničáková ◽  
Klaudia Hložeková ◽  
Rastislav Dosoudil ◽  
Marek Gořalík ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Carbon Black ◽  
Zinc Ferrite ◽  
Mechanical Characteristics ◽  
Hybrid Composites ◽  
Rubber Matrix ◽  
Butadiene Rubber ◽  
Frequency Range ◽  
Manganese Zinc ◽  
Manganese Zinc Ferrite

In the present work, composite materials were prepared by incorporation of manganese-zinc ferrite, carbon black and combination of ferrite and carbon black into acrylonitrile-butadiene rubber (NBR). For cross-linking of composites, standard sulfur-based curing system was applied. The main goal was to investigate the influence of the fillers on the physical-mechanical properties of composites. Then, the electromagnetic absorption shielding ability was investigated in the frequency range 1 MHz–3 GHz. The results revealed that composites filled with ferrite provide sufficient absorption shielding performance in the tested frequency range. On the other hand, ferrite behaves as an inactive filler and deteriorates the physical-mechanical characteristics of composites. Carbon black reinforces the rubber matrix and contributes to the improvement of physical-mechanical properties. However, composites filled with carbon black are not able to absorb electromagnetic radiation in the given frequency range. Finally, the combination of carbon black and ferrite resulted in the modification of both physical-mechanical characteristics and absorption shielding ability of hybrid composites.

scholarly journals Microstructure, Tensile Properties and Hardness Behavior of Al7075 Matrix Composites Reinforced With Graphene Nanoplatelets and Beryl Fabricated by Stir Casting Method

2019 ◽  
Vol 9 (1) ◽  
pp. 6761-6765 ◽  
Keyword(s):  
Tensile Strength ◽  
Volume Fraction ◽  
Hybrid Composites ◽  
Matrix Material ◽  
Stir Casting ◽  
Hybrid Nanocomposites ◽  
Homogeneous Distribution ◽  
Casting Technique ◽  
Aluminum 7075 ◽  
Scanning Electron

In this research, an effort is made to familiarize and best potentials of the reinforcing agent in aluminum 7075 matrices with naturally occurring Beryl (Be) and Graphene (Gr) to develop a new hybrid composite material. A stir casting technique was adopted to synthesize the hybrid nanocomposites. GNPS were added in volume fractions of 0.5wt%, 1wt%, 1.5wt%, and 2wt% and with a fixed volume fraction of 6 wt.% of Beryl. As cast hybrid composites were microstructurally characterized with scanning electron microscopy and X-ray diffraction. Microstructure study through scanning electron microscope demonstrated that the homogeneous distribution reinforcement Beryl and GNPs into the Al7075 matrix. Brinell hardness and tensile strength of synthesized materials were investigated. The hybrid Al7075-Beryl-GNPs composites showed better mechanical properties compared with base Al7075 matrix material. The ascast Al7075-6wt.% Beryl-2wt.%GNPs showed 49.41% improvement in hardness and 77.09% enhancement in ultimate tensile strength over Al7075 alloy.

Behavior of epoxy reinforced banana glass fiber hybrid composite with nanoclay interference

2021 ◽  
pp. 095440622110357
Author(s):  
Sudhagar M ◽  
Kannan TK ◽  
Benjamin Lazarus S ◽  
Rajasekar R ◽  
Sachin S Raj
Keyword(s):  
Glass Fiber ◽  
Hybrid Composite ◽  
Hybrid Composites ◽  
Wear Behavior ◽  
Hybrid Nanocomposites ◽  
Compression Moulding ◽  
Banana Fiber ◽  
Optimum Result ◽  
Character Study ◽  
Novel Material

Recent years, Polymer matrix hybrid composites have a greater attention in industry and research due to growing demand for versatile applications. The present work focused on the development of epoxy based hybrid nanocomposites. Nanoclay is another novel material that is widely used in the research. In this investigation, nanoclay dispersed hybrid composite materials has been studied for mechanical and wear behavior. Glass fiber and banana fiber combined epoxy laminates (EGB) were reinforced with nanoclay at different weight fractions of 2%, 4%, 6%, and 8% using compression moulding. The enhanced properties of the nanoclay hybrid composites were analyzed with other specimens. Water absorption character study was also conducted. Morphological study was performed using Scanning Electron Microscope. It was observed that an optimum result attained with 4 wt% nanoclay reinforced composite with an increase in tensile strength of 8.62%, flexural strength of 30.19%, and impact strength of 48.15% when compared to EGB. Further the wear resistance of 4 wt% nanoclay hybrid composite showed an increase of 19.4% than the EGB composite.

scholarly journals Layer-by-Layer Deposition of Copper and Phosphorus Compounds to Develop Flame-Retardant Polyamide 6/Montmorillonite Hybrid Composites

2020 ◽  
Vol 10 (14) ◽  
pp. 5007 ◽  
Author(s):  
Tomasz M. Majka ◽  
Monika Witek ◽  
Paulina Radzik ◽  
Karolina Komisarz ◽  
Agnieszka Mitoraj ◽  
...  
Keyword(s):  
Hybrid Composites ◽  
Protective Coatings ◽  
Synergistic Effects ◽  
Polyamide 6 ◽  
Hybrid Nanocomposites ◽  
Phosphorus Compounds ◽  
Double Layers ◽  
Layer By Layer ◽  
Maximum Point ◽  
Layer Deposition

Nowadays, increasing attention is devoted to the search for polymeric composite materials that are characterized by reduced flammability. In this work, the layer-by-layer (LbL) technique was applied to form multilayered protective coatings for polyamide 6/montmorillonite (PA6/MMT) hybrid nanocomposites. This time, the double layers LbL deposition was used in order to improve the thermal properties or flammability of PA6 materials. Our goal was to check how five, 10, and 15 triple-layer deposition onto the surface of PA6 and PA6/MMT composites influenced these relevant properties. For this reason, disodium H-phosphonate, sodium montmorillonite, and iodo-bis(triphenylphosphino)copper were used for polyelectrolyte solution preparation. It was found that the LbL method could be successfully used to improve the flammability characteristics of polyamide 6-based composites. Nevertheless, the deposition of the copper complex should be combined with other flame retardants—preferentially containing phosphorus—which enable synergistic effects to occur. Moreover, microscopic observations confirmed that the surfaces on which the formation of interwoven fibrous crystal structures was observed had a tendency to protect the entire material against the destructive effects of heat, contributing, among other things, to reduce the maximum point of heat release rate (PHRR).

Completely green synthesis of silver nanoparticle decorated MWCNT and its antibacterial and catalytic properties

2016 ◽  
Vol 88 (1-2) ◽  
pp. 71-81 ◽  
Author(s):  
Sneha Mohan ◽  
Oluwatobi S. Oluwafemi ◽  
Sandile P. Songca ◽  
Didier Rouxel ◽  
Patrice Miska ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Green Synthesis ◽  
Silver Nanoparticle ◽  
Large Scale ◽  
Hybrid Nanocomposites ◽  
Antibacterial Efficacy ◽  
Hybrid Nanocomposite ◽  
Ag Nps ◽  
Simple Method ◽  
G Ratio

AbstractWe herein report a simple large scale green synthesis route for the synthesis of silver nanoparticle (Ag-NP) multi walled carbon nanotubes (MWCNTs) hybrid nanocomposite (Ag-MWCNTs). The as-synthesized hybrid nanocomposite were characterized using UV-Vis absorption spectroscopy, Fourier transform infra-red spectroscopy (FTIR), Raman spectroscopy, X-ray diffraction analysis (XRD) and high resolution transmission electron microscopy (HR-TEM). Raman spectroscopy analysis showed an increase in the D/G ratio of Ag-MWCNTs hybrid nanocomposites when compare with that of functionalized MWCNTs (F-MWCNTs) attributed to the presence of Ag-NPs on the surface of the F-MWCNTs. The as-synthesized Ag-MWCNTs nanocomposites showed strong antibacterial efficacy against Escherichia coli compared to the Ag-NPs and MWCNTs. The catalytic potential of the Ag-MWCNTs hybrid nanocomposite was investigated for the first time by studying the reduction of 4-nitrophenol to 4-aminophenol in the presence of sodium borohydride at 299 K at various reaction times. The reaction follows first order kinetics with a rate constant of 5.18×10−1 s−1. It is believed that, the large scale synthesis of such hybrid nanocomposites via simple method using non-toxic reagent will not only enhance its antibacterial efficacy, durability and biocompatibility, it will also minimize its biotoxcity and environmental impacts.

Preparation of Ag Doped Hydroxyapatite- Fe3O4-Chitosan Composites: In Vitro Biocompatibility Study on MG-63 Cells for Orthopedic Applications

2018 ◽  
Vol 24 (8) ◽  
pp. 5901-5906
Author(s):  
U Anjaneyulu ◽  
B Priyadarshini ◽  
U Vijayalakshmi
Keyword(s):  
Cell Lines ◽  
Hybrid Composites ◽  
Sol Gel ◽  
Hybrid Nanocomposites ◽  
In Vitro Biocompatibility ◽  
Ball Milling Technique ◽  
Co Precipitation ◽  
Orthopedic Applications ◽  
Biocompatibility Study

Present paper deals with the development of hybrid nanocomposites which combination of Ag doped Hydroxyapatite (Ag:HAP)-Magnetite nanoparticles (Fe3O4NPs) and Chitosan. In this present investigation, we have employed sol–gel method to synthesize Ag:HAP using 5% of Ag concentrations. Furthermore, co-precipitation technique was employed to prepare Fe3O4 NPs and Ag doped HAP was mixed with it to develop hybrid composites. The planetary ball milling technique was used to incorporate the fabricated Ag:HAP-Fe3O4 composite material into the biopolymer chitosan at wt% of 50:25:25 respectively. In Vitro biocompatibility of Ag:HAP-Fe3O4 CS hybrid composites were evaluated by MTT assay using MG-63 cell lines for 24–48 h at 200–1000 μg/ml concentrations. Further, these hybrid composites were characterized by using ATR-FTIR, XRD and SEM techniques. The fabricated hybrid composite was found to be biologically compatible with MG-63 osteoblast cell lines to use in biomedical applications.

Preparation of Ag–Polyacrylamide Nanocomposites by Ultraviolet Irradiation Technique

2010 ◽  
Vol 44-47 ◽  
pp. 2199-2202 ◽  
Author(s):  
Wei Pan ◽  
Yan Chen
Keyword(s):  
Ultraviolet Irradiation ◽  
Hybrid Composites ◽  
Polymer Chains ◽  
Hybrid Nanocomposites ◽  
Stability Behavior ◽  
Transmission Electron ◽  
Ag Particles ◽  
Pure Phase ◽  
Ft Ir ◽  
Nanoparticle Composites

Polyacrylamide (PAM)/silver (Ag) nanoparticle composites were prepared via ultraviolet irradiation of a mixture solution of silver nitrate (AgNO3) and PAM. The resultant composites were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM) thermogravimetric (TG) and Fourier transform infrared (FT-IR). XRD results showed that pure phase Ag was obtained in the prepared nanocomposites. TEM results showed that the Ag particles were in sphere shape with 8-25nm diameter in the as-prepared nanocomposites. FTIR characterized the interaction between polymer chains and Ag particles in hybrid nanocomposites. The TGA results showed improved thermoresistance and high thermal stability behavior of hybrid composites.

Synthesis and Characterization of PVDF-Based SWNT/GO Hybrid Films

2012 ◽  
Author(s):  
Nirmal Shankar Sigamani ◽  
Zoubeida Ounaies ◽  
Henry Sodano
Keyword(s):  
Polyvinylidene Fluoride ◽  
Room Temperature ◽  
Breakdown Strength ◽  
Hybrid Nanocomposites ◽  
Hybrid Nanocomposite ◽  
Frequency Range ◽  
Hybrid Films ◽  
Walled Carbon Nanotubes ◽  
Pure Pvdf

Hybrid nanocomposites with single walled carbon nanotubes (SWNT) and graphene oxide (GO) as nanofillers and polyvinylidene fluoride (PVDF) as a polymer were synthesized as potential electronic active polymers (EAPs) with high breakdown strength. A co-solvent method was developed to achieve exfoliation and dispersion of GO in PVDF. The microstructure of the PVDF was found to be predominantly γ phase. Percent crystallinity of PVDF increased due to the addition of the hybrid nanofillers. And, at room temperature, the storage modulus is increased by 56.26% over the pure PVDF. The dielectric constant increased from ∼7 to ∼25 for the hybrid nanocomposites as compared to pure PVDF at 1KHz measurement frequency. Dielectric loss of the hybrid nanocomposite is found less than 0.6 for the frequency range from 20 Hz–1MHz. Electrical conductivity of the hybrid nanocomposite increase by nearly two orders of magnitude at 1KHz when compared to pure PVDF. The effect of the presence of these hybrid nanofillers on microstructure and properties of PVDF are discussed.

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