Search for: nanocomposite
Total 948 records
Article Asian Journal of Chemistry ; Volume 22, Issue 1 , 2010 , Pages 797-807 ; 09707077 (ISSN) ; Bazgir, S ; Tamizifar, M ; Nemati, A ; Arzanp, K ; Sharif University of Technology
Epoxy-clay nanocomposites were prepared using silane modified montmorillonite. The clay was first purified using a 1-inch hydrocyclon apparatus. The purified clay was modified with various amounts of (γ)-3-aminopropyltrimethoxysilane as a modifier. The synthesized organoclay was mixed and swollen by a mixture of epoxy resin and stoichiometric amount of curing agent at different temperature, mixing time and agitation. Finally, the compounds were cured in an oven at 90 °C for 2 h. The nanostructure materials were characterized using X-ray diffraction and transmission electron microscopy. The X-ray diffraction patterns showed that the impurities and large particles (greater than 5 microns) are...
Preparation and characterization of self-electrical stimuli conductive gellan based nano scaffold for nerve regeneration containing chopped short spun nanofibers of PVDF/MCM41 and polyaniline/graphene nanoparticles: Physical, mechanical and morphological studies, Article International Journal of Biological Macromolecules ; 2020 ; Ramazani S., A ; H Shirazi, F ; Hassanzadeh Nemati, N ; Sharif University of Technology
Elsevier B.V 2020
Conductive self -electrical stimuli bioactive scaffolds could be used the potential for peripheral nerve regeneration with the maximum efficiency. To produce such conductive self-electrical stimuli bioactive scaffolds, chopped spun piezoelectric nanofibers of polyvinylidene fluoride/mesoporous silica nanoparticle (PVDF/MCM41) are prepared and incorporated in gellan/polyaniline/graphene (gellan/PAG) nanocomposites which have been previously prepared by incorporation of polyaniline/graphene (PAG) nanoparticles in gellan gel at 80 °C. Highly conductive binary doped polyaniline/graphene nanoparticles are prepared by chemical oxidative polymerization of aniline monomer using in-suite...
Flexible bactericidal graphene oxide–chitosan layers for stem cell proliferation [electronic resource], Article Journal of Applied Surface Science ; 15 May 2014, Volume 301, Pages 456–462 ; Akhavan, O ; Simchi, A. (Abdolreza) ; Sharif University of Technology
Graphene oxide (GO)–chitosan composite layers with stacked layer structures were synthesized using chemically exfoliated GO sheets (with lateral dimensions of ∼1 μm and thickness of ∼1 nm), and applied as antibacterial and flexible nanostructured templates for stem cell proliferation. By increasing the GO content from zero to 6 wt%, the strength and elastic modulus of the layers increased ∼80% and 45%, respectively. Similar to the chitosan layer, the GO–chitosan composite layers showed significant antibacterial activity (>77% inactivation after only 3 h) against Staphylococcus aureus bacteria. Surface density of the actin cytoskeleton fibers of human mesenchymal stem cells (hMSCs) cultured...
Microstructure and compressibility of SiC nanoparticles reinforced Cu nanocomposite powders processed by high energy mechanical milling [electronic resource], Article Ceramics International ; Volume 40, Issue 1, Part A, January 2014, Pages 951–960 ; Salahi, E ; Alikhani Hesari, F ; Simchi, A ; Kim, H. S ; Sharif University of Technology
Cu/SiC nanocomposite powders with homogeneously distributed nanosize SiC particles were produced by high energy mechanical milling (MM). Scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and micro-hardness and density measurements were performed to understand the effects of microstructure and hardness on compaction behavior during MM. The effects of SiC nanoparticle content and mechanical milling time on apparent density (AD) and tap density (TD) of the nanocomposite powders were systematically investigated. The Hausner ratio (HR), defined as TD to AD, were estimated to evaluate friction between the particles. Increasing MM duration and SiC content resulted...
Nanodiamonds for surface engineering of orthopedic implants: Enhanced biocompatibility in human osteosarcoma cell culture [electronic resource], Article Diamond and Related Materials ; Volume 40, 2013, Pages 107-114 ; Shokrgozar, M. A ; Mehrjoo, M ; Tamjid, E ; Simchi, A ; Sharif University of Technology
Recently, nanodiamonds have attracted interest in biomedical applications such as drug delivery, targeted cancer therapies, fabrication of tissue scaffolds, and biosensors. We incorporated diamond nanoparticles in alginate–bioactive glass films by electrophoretic process to prepare functional coatings for biomedical implants. Turbidity examination by time-resolved laser transmittance measurement revealed that a stable multi-component aqueous suspension of alginate, bioactive glass and diamond particles could be obtained at concentrations of 0.6, 1.3, and 0.65 g/l, respectively. Uniform films with ~ 5 μm thickness were deposited on 316 stainless steel foils by employing constant field...
Rheological and morphological behaviors of polyamide 6/acrylonitrile-butadiene-styrene/nanoclay nanocomposites, Article Journal of Thermoplastic Composite Materials ; Vol. 27, issue. 10 , 1 October , 2014 , pp. 1399-1416 ; ISSN: 08927057 ; Ramazani, S. A ; Ghasemi, I ; Vaziri, A ; Sharif University of Technology
In this study, the effect of nanoclay on the rheological and morphological properties of polyamide 6 (PA6)/acrylonitrile-butadiene-styrene (ABS) blends was investigated. The scanning electron microscopy micrographs showed that with increment in the nanoclay content, the dispersed phase droplets size and their polydispersity index decreased, and the finer and more uniform dispersed phase was obtained. The transmission electron microscopy micrographs of nanocomposites indicated well-dispersed nanoclay tactoids in the polymer matrix produced by exfoliation of the nanoclay in the polymeric blends. Dynamic strain sweep experiments showed that the extent of the linear viscoelastic region is...
Rheological and morphological properties of nanocomposites based on PA66/PA6/multi-walled carbon nanotube prepared by melt mixing, Article ICCM International Conferences on Composite Materials, 21 August 2011 through 26 August 2011, Jeju ; August , 2011 ; Shojaei, A ; Bagheri, R ; Sharif University of Technology
Photocatalytic properties of mesoporous TiO2 nanocomposites modified with carbon nanotubes and copper, Article Ceramics International ; 2016 ; 02728842 (ISSN) ; Abbaspour, S ; Masood, M ; Mirsattari, S. N ; Vahedi, A ; Mackenzie, K. J. D ; Sharif University of Technology
Elsevier Ltd 2016
The photocatalytic activity of mesoporous TiO2 modified by the addition of carbon nanotubes (CNTs) and Cu is reported. Nanocomposites of carbon nanotubes (CNTs) containing varying amounts of Cu were formed by treatment with Cu2+ then reduced to Cu0 using NaBH4 as the reducing agent. The mesoporous TiO2, synthesized by a sol-gel method from titanium isopropoxide, was combined with the CNT/Cu nanocomposites to form the photocatalysts which were characterized by XRD, SEM, TEM, FTIR, XPS and BET surface area analysis. The photocatalytic properties of the mesoporous TiO2 composites were studied by measuring the degradation of methyl orange (MO) which was optimal in the sample containing 20wt% of...
Preparation of polyaniline/graphene coated wearable thermoelectric fabric using ultrasonic-assisted dip-coating method, Article Materials for Renewable and Sustainable Energy ; Volume 9, Issue 4 , 2020 ; Ramazani Saadatabadi, A ; Siadati, M. H ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH 2020
Abstract: The use of thermoelectric fabrics for powering wearable devices is expected to become widespread soon. A thermoelectric fabric was prepared by coating nanocomposite of polyaniline/graphene nanosheets (PANI/GNS) on a fabric. Four samples of the fabric containing different wt% of GNS (0.5, 2.5, 5, and 10) were prepared. To characterize the samples, Fourier transform infrared (FTIR) spectra, attenuated total reflectance-Fourier transform infrared (AT-FTIR) spectra, field-emission scanning electron microscopy (FE-SEM), electrical conductivity and Seebeck coefficient measurements were used. The electrical conductivity increased from 0.0188 to 0.277 S cm−1 (from 0.5 to 10 wt% of the GNS...
Manufacturing and structural evaluation of polymer derived sioc/tic and SiOC/TiC/mullite nanocomposites, Article Iranian Journal of Materials Science and Engineering ; Volume 18, Issue 3 , 2021 ; 17350808 (ISSN) ; Godary, T ; Abdollahi, S ; Anousheh, M ; Khachatourian, A. M ; Sharif University of Technology
Iran University of Science and Technology 2021
Silicon oxycarbide (SiOC) materials derived from silicone attracted great attention for their superior high-temperature behavior. In the present study, Si (Ti)OC and Si (Ti,Al)OC nanocomposites, in which alkoxide precursors were used with the main silicone precursor, have been compared with SiOC material. Although in SiOC, C was bonded with Si in a carbon-rich SiOC phase, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) showed that TiC was the preferred state for C atoms upon adding Ti into the system. This claim was also substantiated by Raman spectroscopy, where adding Ti into the system lowered the intensity of the D band, indicating the high affinity of C to...
Article Emergent Materials ; 2021 ; 25225731 (ISSN) ; Ahmadi, S ; Rabiee, M ; Bagherzadeh, M ; Vahabi, H ; Jouyandeh, M ; Saeb, M. R ; Sharif University of Technology
Springer Nature 2021
In this work, a green synthesis method was designed and practiced to develop bioactive and biocompatible carbon-based nanocomposites biomaterials. ZnO nanoparticles were synthesized in assistance of leaf extracts and added to a composite nanostructure composed of the reduced graphene oxide (rGO) and multi-walled carbon nanotubes (MWCNT). The resulting green nanocomposite revealed ability to make π-π interactions, hydrogen bonding, and van der Waals interactions with the doxorubicin (DOX). Then, the surface morphology of the synthesized nanocomposite was investigated, and the interrelationship between the surface morphology, relative cell viability, and drug uptake and release behavior were...
Article Journal of Bioresources and Bioproducts ; Volume 6, Issue 3 , 2021 , Pages 215-222 ; 23699698 (ISSN) ; Rabiee, N ; Seidi, F ; Farasati Far, B ; Bagherzadeh, M ; Lima, E. C ; Rabiee, M ; Sharif University of Technology
KeAi Communications Co 2021
A one-pot synthesis method was conceptualized and implemented to develop green carbon-based nanocomposites working as biosensors. Porphyrin was synthesized to adorn the surface of nanocomposites making them highly sensitive for giving rise to π-π interactions between the genetic materials, proteins and porphyrin rings. The hydrogen bond formed between the proteins (analytes) and the nitrogen in the porphyrin structure as well as the surface hydroxyl groups was equally probable. In this context, different forms of porphyrins were incorporated to explore the interrelationship between the surface morphology and the ability of detection of genetic material and/or proteins by the aid of the...
Article Journal of the Iranian Chemical Society ; Volume 17, Issue 6 , 31 January , 2020 , Pages 1259-1281 ; Keikavousi Behbahan, A ; Sharif University of Technology
Heavy metals belong to a group of lethal environmental pollutants. Ongoing efforts targeted at safeguarding public health have led to considerable attention being focused on methods that allow efficient extraction of these toxic substances. Polymer nanocomposites (PNCs) with their special characteristics are a class of adsorbents that demonstrate high potential for use in heavy metal extraction. As this process of removal is predominantly governed by adsorption, various parameters in PNCs’ chemical structure, as well as the metal solutions, can have a significant effect on the adsorption process. Herein, this review undertakes a survey of recently developed PNCs and their metal adsorption...
Article Polymers and Polymer Composites ; Volume 29, Issue 9_suppl , 2021 , Pages S556-S564 ; 09673911 (ISSN) ; Moghim, M. H ; Eqra, N ; Sharif University of Technology
SAGE Publications Ltd 2021
The aims of this research are to elucidate the role of graphene oxide on the mechanical properties of epoxy and also to obtain an equation for the modeling of its behavior. Accordingly, graphene oxide/epoxy nanocomposite samples are fabricated using the solution casting method. Tensile, flexural, SEM and FTIR tests are conducted on epoxy and the nanocomposite samples afterwards. The obtained results show that the tensile strength of epoxy improves even at low contents of graphene oxide such that 0.3 wt.% of GO yields an improvement of approximately 11.5%. The flexural strength of epoxy is also enhanced by 5.8% with 0.5 wt.% GO. Then, it decreases due to the agglomeration with increasing the...
Article Polymer Reviews ; Volume 56, Issue 1 , 2016 , Pages 70-112 ; 15583724 (ISSN) ; Mai, Y. W ; Bagheri, R ; Pearson, R. A ; Sharif University of Technology
Taylor and Francis Inc 2016
In this paper, we review recent progress made in the field of epoxy-based binary and ternary nanocomposites containing three-, two-, and one-dimensional (i.e., 3D-, 2D-, and 1D) nano-size fillers with a special focus on their fracture behaviors. Despite investigations conducted so far to evaluate the crack-resistance of epoxy nanocomposites and attempts made to clarify the controlling toughening mechanisms of these materials, some questions remain unsolved. It is shown that silica nanoparticles can be as effective as rubber particles in improving the fracture toughness/energy; but incorporation of carbon nanotubes (CNTs) or clay platelets in epoxy matrices delays crack growth only modestly....
On variations of the interphase thickness and the slope of strengthening by clay addition in exfoliated polymer-clay nanocomposites, Article Polymer (United Kingdom) ; Volume 90 , 2016 , Pages 302-308 ; 00323861 (ISSN) ; Khederlou, Kh ; Payandehpeyman, J ; Bagheri, R ; Sharif University of Technology
Polymer-clay nanocomposites (PCNs) have received intensive attention in recent years because of their wide domain of applications. The present report provides an approach to calculate the thickness of nanometric interphase region in exfoliated PCNs based on the information about their macroscopic modulus and their nanoclay content. First, the concept of interphase region in PCNs is explained with an “algae explanation”. Then, a series of parametric finite element simulations together with analytical equations are employed to derive an explicit relationship between the interphase thickness and the PCN macroscopic modulus. The obtained analytical model considers the structural impact of the...
Investigation of Mechanical Milling Effects on Al-Cu and Al-CuO Powder Mixture Morphological and Structural Characteristic and Mechanical Properties Changes Resultant from Age Hardening, M.Sc. Thesis Sharif University of Technology ; Simchi, Abdolreza
In the present work, nanocrystalline Al-4wt%Cu alloy reinforced with nanometric Al2O3 particles was synthesized by in-situ reactive milling of Al and CuO powder mixture and hot extrusion. The effect of nanometric Al2O3 particles on the aging behavior and mechanical properties of this alloy was investigated. During mechanical milling, copper oxide were reduced and dissolved in the aluminum lattice. consequently, Al(Cu) solid solution matrix was produced. Also, nanometric Al2O3 particles were also distributed in the matrix uniformly. The powder blend was then pressed in an Al can at 100 MPa pressure and subsequently extruded at 450 0C at the extrusion ratio of 16:1. The density of the...
M.Sc. Thesis Sharif University of Technology ; Forounchi, Massoud
PVDF (polyvinylidene fluoride) magnetic nanocomposite films were prepared by solution casting using two types of nanomagnetic particles: (i) magnetic nanoparticles synthesized by using an alkaline solution of mixed ferrous/ferric salts along with oleic acid as a coating agent at 70˚C; (ii) Fe3O4 nanoparticles prepared by hydrolysis of aqueous solution of ferrous/ferric salts with potassium hydroxide at room temprature. Scanning electron microscopy (SEM) showed that the PVDF magnetic nanocomposite had a porous structure with Fe3O4 nanoparticles dispersed inside the porous polymer matrix. The presence of crystalline magnetite within the polymer matrix was confirmed by X-Ray diffraction method...
M.Sc. Thesis Sharif University of Technology ; Shojaei, Akbar
Chitosan is a biocompatible and biopolymer with unique characteristics. Nanodiamonds that are basically carbon based nanoparticle have excellent mechanical, thermal stability biocompatibility bahviors. Combination of these two materials helps to the advantage of all the desirable features of both material and compensate low mechanical properties and strength of chitosan. In this study, we examine the composition of different percentages of nanodiamonds in chitosan and effect of modification on properties of the nanocomposites. The thermal behaviour, swelling behaviour and water contact angle of different nanocomposites were analyzed. Finally, to determine the distribution of the...
M.Sc. Thesis Sharif University of Technology ; Ghorbani, Mohammad
The synthesis and usage of nanoscaled TiO2 accompanied by the photocatalytic activity were experimented through a systematic research. The synthesis was based on the sol-gel method at low temperatures and atmospheric pressure. In recent years, many endeavors have been made so as to enhance the efficiency of TiO2 photocatalytic activity. The studies show that the inclusion of SiO2 into the TiO2 can give rise to the photocatalytic activity relevant to the derived composite Nanoparticles with regard to the pure TiO2. In this study, the production of TiO2-SiO2 Nanocomposite layers was proceeded via the sol method and the effect of SiO2 increasing and its amount in the primary solution on the...