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Production and characterization of UHMWPE/fumed silica nanocomposites
, Article Polymer Composites ; Volume 33, Issue 10 , 2012 , Pages 1858-1864 ; 02728397 (ISSN) ; Saremi, M. G ; Amoli, B. N ; Izadi, H ; Sharif University of Technology
Wiley
2012
Abstract
Ultrahigh-molecular-weight polyethylene (UHMWPE)/fumed silica nanocomposites were prepared via in situ polymerization using a bi-supported Ziegler-Natta catalytic system. Nanocomposites with different nanoparticle weight fractions were produced in order to investigate the effect of fumed silica on thermal and mechanical properties of UHMWPE/fumed silica nanocomposites. The viscosity average molecular weight (M) of all samples including pure UHMWPE as the reference sample and nanocomposites were measured. Scanning electron microscope (SEM) images showed the homogenous dispersion of nanoparticles throughout the UHMWPE matrix while no nanoparticle cluster has been formed. Crystallization...
Preparation of ultrahigh-molecular-weight polyethylene/carbon nanotube nanocomposites with a Ziegler-Natta catalytic system and investigation of their thermal and mechanical properties
, Article Journal of Applied Polymer Science ; Volume 125, Issue SUPPL. 1 , 2012 , Pages E453-E461 ; 00218995 (ISSN) ; Ramazani, S. A. A ; Izadi, H ; Sharif University of Technology
Wiley
2012
Abstract
In this research, ultrahigh-molecular-weight polyethylene (UHMWPE)/multiwalled carbon nanotube (MWCNT) nanocomposites with different nanotube concentrations (0.5, 1.5, 2.5, and 3.5 wt %) were prepared via in situ polymerization with a novel, bisupported Ziegler-Natta catalytic system. Magnesium ethoxide [Mg(OEt) 2] and surface-functionalized MWCNTs were used as the support of the catalyst. Titanium tetrachloride (TiCl 4) accompanied by triethylaluminum constituted the Ziegler-Natta catalytic system. Preparation of the catalyst and the polymerization were carried out in the slurry phase under an argon atmosphere. Support of the catalyst on the MWCNTs was investigated with Fourier transform...
Simultaneous use of physical and chemical dispersants for electrical conductivity enhancement in polyamide 6/carbon nanotube/conductive carbon black hybrid nanocomposites
, Article Polymer-Plastics Technology and Materials ; 2021 ; 25740881 (ISSN) ; Jahanaray, B ; Pircheraghi, G ; Bagheri, R ; Sharif University of Technology
Taylor and Francis Ltd
2021
Abstract
Polyamide 6 (PA6)/carbon nanotube (CNT)/conductive carbon black (CCB) nanocomposites with the incorporation of physical and chemical dispersants were prepared via melt blending method to examine the synergistic enhancement of electrical conductivity. Investigation of modified CNT with octadecyl triphenyl phosphonium chloride (OTPC-CNT) as physical dispersant was performed by Fourier transform infrared, nuclear magnetic resonance, Raman spectroscopy, and thermogravimetric analysis. Morphological, electrical, rheological, and mechanical properties of PA6/CNT/CCB nanocomposites were examined by field emission scanning electron microscopy, transmission electron microscopy, digital insulation...
Simultaneous use of physical and chemical dispersants for electrical conductivity enhancement in polyamide 6/carbon nanotube/conductive carbon black hybrid nanocomposites
, Article Polymer-Plastics Technology and Materials ; Volume 61, Issue 3 , 2022 , Pages 263-275 ; 25740881 (ISSN) ; Jahanaray, B ; Pircheraghi, G ; Bagheri, R ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
Polyamide 6 (PA6)/carbon nanotube (CNT)/conductive carbon black (CCB) nanocomposites with the incorporation of physical and chemical dispersants were prepared via melt blending method to examine the synergistic enhancement of electrical conductivity. Investigation of modified CNT with octadecyl triphenyl phosphonium chloride (OTPC-CNT) as physical dispersant was performed by Fourier transform infrared, nuclear magnetic resonance, Raman spectroscopy, and thermogravimetric analysis. Morphological, electrical, rheological, and mechanical properties of PA6/CNT/CCB nanocomposites were examined by field emission scanning electron microscopy, transmission electron microscopy, digital insulation...
PEG-co-polyvinyl pyridine coated magnetic mesoporous silica nanoparticles for pH-responsive controlled release of doxorubicin
, Article International Journal of Polymeric Materials and Polymeric Biomaterials ; Volume 64, Issue 11 , 2015 , Pages 570-577 ; 00914037 (ISSN) ; Mazaheri Tehrani, Z ; Bennett, C ; Sharif University of Technology
Taylor and Francis Inc
2015
Abstract
In the present work a pH responsive drug nanocarrier based on magnetic mesoporous silica nanoparticles (MMSN) and polyethylene glycol-co-polyvinyl pyridine (PEG-co-PVP) was prepared. The core-shell nanocarrier was formed due to electrostatic interaction between protonated polyvinyl pyridine and surface modified MMSN with carboxylate groups. This carrier was used for pH-controllable doxorubicin release. The maximum release was occurred at pH 5.5 (pH of endosomes). This carrier was characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, UV-Vis spectrophotometer, scanning electron microscope, and high-resolution transmission electron microscope techniques. Also the...
Thermogravimetric analysis and kinetic study of heavy oil pyrolysis
, Article Petroleum Science and Technology ; Volume 34, Issue 10 , 2016 , Pages 911-914 ; 10916466 (ISSN) ; Hami, M. R ; Sharif University of Technology
Taylor and Francis Inc
2016
Abstract
ABSTRACT: Pyrolysis, so-called devolatilization, is one of the first steps of all thermochemical processes occurring in an inert atmosphere. The authors discuss the main kinetic features of heavy oil pyrolysis, on the basis of the data derived m from a TGA analysis and by using a kinetic model. The samples were heated over a range of temperature from 400 K to 430°C at various heating rates between 10 and 80°C/min. Experimental results showed that the effect of time is considerable in the case of tar conversion, compared to char and gases
Preparation of activated carbon dots from sugarcane bagasse for naphthalene removal from aqueous solutions
, Article Separation Science and Technology (Philadelphia) ; Volume 53, Issue 16 , 2018 , Pages 2536-2549 ; 01496395 (ISSN) ; Borghei, S. M ; Rashidi, A ; Takdastan, A ; Sharif University of Technology
Taylor and Francis Inc
2018
Abstract
The synthesis of cheap and environmental friendly adsorbent from residual sugarcane bagasse was done for the removal of naphthalene from aqueous solution. The activated carbon dot was obtained by KOH chemical activation of carbon dots. The characteristics of carbon dots and activated carbon dots were determined using field emission scanning electron microscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, and thermogravimetric analysis. A series of experiments were conducted in a batch system to assess the effect of the system variables, i.e., initial pH, initial naphthalene concentration, adsorbent dosage, and contact time. The kinetic data showed better fit to the...
Preparation of stable dispersion of graphene using copolymers: dispersity and aromaticity analysis
, Article Soft Materials ; Volume 17, Issue 2 , 2019 , Pages 190-202 ; 1539445X (ISSN) ; Yasin, S ; Ramzan, N ; Iqbal, T ; Akhtar, M. N ; Sharif University of Technology
Taylor and Francis Inc
2019
Abstract
In this study, effectiveness of non-ionic block copolymers such as Lugalvan BNO12 and Triton X series (Triton X100 & Triton X405) has been reported for graphene dispersion in aqueous solutions. Stability of the aqueous graphene dispersions is investigated using UV–visible spectroscopy, Rheological, and Conductivity studies. Adsorption isotherms are constructed to determine the amount of polymers adsorbed on the surface of graphene by the spectroscopic analysis. Lugalvan BNO12 has been found to be adsorbed in higher amounts on the graphene surface compared to the Triton X series polymers. Thermogravimetric analysis (TGA) and Fourier Transform Infrared (FTIR) Spectroscopy investigations...
Adsorptive removal of petroleum hydrocarbons from aqueous solutions by novel zinc oxide nanoparticles grafted with polymers
, Article Petroleum Science and Technology ; Volume 34, Issue 8 , 2016 , Pages 778-784 ; 10916466 (ISSN) ; Hasani, A. H ; Ahmad Panahi, H ; Borghei, S. M ; Sharif University of Technology
Taylor and Francis Inc
Abstract
Zinc oxide nanoparticles were synthesized and modified by a three-stage method. Elemental analysis, Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning and transmission electron microscopy, and Brunauer–Emmett–Teller method were applied to characterize the nanoparticles. These nanoparticles were evaluated for toluene adsorption from aqueous solutions as a representative of petroleum hydrocarbon removal. The optimum adsorption condition achieved at pH of 6 and contact time of 30 min. The adsorption isotherms were fitted to the Langmuir model. The measured adsorption capacity was 12.8 mg g−1. This study demonstrated that these nanoparticles could be used as an...
Thermal degradation behavior and kinetic analysis of ultra high molecular weight polyethylene based multi-walled carbon nanotube nanocomposites prepared via in-situ polymerization
, Article Journal of Macromolecular Science, Part A: Pure and Applied Chemistry ; Volume 49, Issue 9 , 2012 , Pages 749-757 ; 10601325 (ISSN) ; Saadatabadi, A. R ; Khorasheh, F ; Sharif University of Technology
T&F
2012
Abstract
Thermal degradation behavior of multi-wall carbon nanotubes (MWCNTs)/ultra high molecular weight polyethylene (UHMWPE) nanocomposites, with different nanotubes contents (0.5, 1.5 and 3.5 wt%) prepared via in-situ polymerization technique have been investigated using thermal gravimetric analysis (TGA). TGA spectra revealed that these nanocomposites had enhanced thermal stability and no significant mass loss (<0.4 wt%) occurred up to 350°C. Thermal degradation of these UHMWPE/MWCNT nanocomposites was investigated in terms of parameters such as the onset temperature of degradation (T 10), the decomposition temperature at 50% wt loss (T 50), the degradation temperature of maximum rate of the...
Hydrogel nanocomposite based on chitosan-g-acrylic acid and modified nanosilica with high adsorption capacity for heavy metal ion removal
, Article Iranian Polymer Journal (English Edition) ; Volume 24, Issue 9 , September , 2015 , Pages 725-734 ; 10261265 (ISSN) ; Mazaheri Tehrani, Z ; Salimi, H ; Banazadeh, A ; Abedini, N ; Sharif University of Technology
Springer-Verlag London Ltd
2015
Abstract
In this study, a novel hybrid hydrogel based on chitosan, acrylic acid and amine-functionalized nanosilica was prepared and characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis and scanning electron microscopy. This hydrogel nanocomposite was used for removal of Co2+, Cu2+, Pb2+ and Zn2+ ions from aqueous solution. The metal ion adsorption was measured by inductively coupled plasma mass spectrometry. The adsorption behavior showed that the presence of modified nanosilica enhanced the porosity of the hydrogel network and affected its adsorption capacity in response to different parameters such as nanosilica content, metal ion concentration, adsorbent content,...
Fabrication and evaluation of nanocomposite membranes of polyethersulfone/α-alumina for hydrogen separation
, Article Iranian Polymer Journal (English Edition) ; Volume 24, Issue 3 , 2015 , Pages 171-183 ; 10261265 (ISSN) ; Rashidzadeh, M ; Safekordi, A ; Khanbabaei, G ; Sharif University of Technology
Springer-Verlag London Ltd
2015
Abstract
In this study, polyethersulfone (PES)-based nanocomposite membranes with the incorporation of inorganic filler of α-alumina were prepared via thermal phase inversion method. The fabricated flat sheet-mixed matrix membranes were characterized using X-ray diffraction, thermal gravimetric analysis, differential scanning calorimetry, scanning electron microscopy, and atomic force microscope analysis, and the permeation tests were performed for hydrogen, nitrogen and carbon dioxide. Also prepared α-alumina particles were identified by X-ray diffraction and the surface area, total pore volume and average pore diameter of particles were measured with a high-speed gas-sorption analyzer. The...
Novel synthesis of cobalt/poly vinyl alcohol/gamma alumina nanocomposite for catalytic application
, Article Applied Physics A: Materials Science and Processing ; Volume 123, Issue 5 , 2017 ; 09478396 (ISSN) ; Ahadian, M. M ; Rashidi, A ; Karimi, A ; Akhavan, O ; Sharif University of Technology
Springer Verlag
2017
Abstract
In this manuscript, synthesis of cobalt/poly vinyl alcohol (PVA)/gamma alumina nanocomposite via a simple room temperature, as well as its catalyst performance were explored. Brunauer–Emmett–Teller analysis, X-ray diffraction, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy were conducted. The surface area of the polymeric composite was obtained to be 280 m2/g. The cobalt loading on the nanocomposite was measured using inductivity couple plasma. Transmission electron microscopy analysis showed that the size of cobalt crystalline encapsulate inside the polymer was confined to 5 nm. Magnetic property analysis, using vibrating sample magnetometer, confirmed...
Structural, magnetic and dielectric properties of Dy-Co substituted Sr-Ba-Mg-based magnetic oxides
, Article Applied Physics A: Materials Science and Processing ; Volume 127, Issue 11 , 2021 ; 09478396 (ISSN) ; Khan, M. A ; Majeed, A ; Akhtar, M. N ; Ahmad, M ; Hussain, A ; Islam, M ; Nasar, G ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2021
Abstract
In present research six samples of nano X-type hexagonal ferrites with general formula SrBaMg2-xCoxDyyFe28-yO46 (x = 0–1; y = 0–0.1 with step size of 0.2 and 0.02, respectively) were synthesized by sol–gel technique. The temperature required for the phase formation of these materials was estimated using thermogravimetric analysis. X-ray diffraction patterns revealed the pure phase of the prepared materials up to the doping concentration of x = 0.4, y = 0.04 along with the second phase for higher doping concentration. The secondary phase appeared due to the solubility limit of higher ionic radius Dy3+ ions into the hexagonal lattice. The mean crystalline size decreased from 29 to 18 nm while...
Effects of modified titanium dioxide nanoparticles on the thermal and mechanical properties of poly(l-lactide)-b-poly(ε-caprolactone)
, Article Iranian Polymer Journal (English Edition) ; Volume 31, Issue 7 , 2022 , Pages 893-904 ; 10261265 (ISSN) ; Sharif, F ; Ramazani, S. A. A ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2022
Abstract
Incorporating titanium dioxide (TiO2) nanoparticles into the polymeric matrix offers an opportunity to obtain nanocomposites with improved functionality. In this study, the commercial TiO2 nanoparticles (TNP) were surface treated by different concentrations of aminopropyl triethoxy silane (APTS) as a coupling agent and triethylamine (Et3N) as a surface grafting catalyst by an aqueous process to prepare a nanocomposite with superior properties. Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA) were performed to confirm the successful surface modification of TNP. The prepared modified TiO2 nanoparticles (mTNP) with different weight fractions were used as...
Tailoring of structural, dielectric, and magnetic properties of SrBaCu2Fe12O22 hexaferrites by doping with Gd–Co binary mixtures
, Article Applied Physics A: Materials Science and Processing ; Volume 128, Issue 9 , 2022 ; 09478396 (ISSN) ; Khan, M. A ; Akhtar, M. N ; Gulbadan, S ; Ejaz, S. R ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2022
Abstract
Gadolinium (Gd) and cobalt (Co) substituted Sr–Ba–Cu-based Y-type hexaferrites were synthesized with the help of the sol–gel auto-combustion route. XRD (X-ray diffraction) analysis was done to ratify the phase formation of hexaferrites. The impact of Gd3+ substitutions was measured on all the lattice parameters. Lattice constants “a” and “c” were found between 5.879–5.891 Å and 43.185–43.620 Å, respectively. It was observed from the XRD analysis that with an increase in Gd–Co contents, the enhancement in the average crystallite size is noted. The thermal decomposition process was studied using TGA (thermogravimetric analysis), revealing that the precursor may give the ending product when...
Iron oxyhydroxide nanoparticles: green synthesis and their cytotoxicity activity against A549 human lung adenocarcinoma cells
, Article Rendiconti Lincei ; Volume 33, Issue 2 , 2022 , Pages 461-469 ; 20374631 (ISSN) ; Alijani, H. Q ; Hashemi Shahraki, S ; Naderifar, M ; Rahimi, S. S ; Abolhasani Zadeh, F ; Iravani, S ; Haghighat, M ; Khatami, M ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2022
Abstract
Iron oxyhydroxide (α-FeOOH, Goethite) is one of the most thermodynamically stable iron oxides and a widespread soil mineral. In this study, a mixture of two phenolic extracts of rosemary and Echinacea was utilized as stabilizing and reducing agents for the synthesis of Goethite (FeOOH) nanoparticles without utilizing harmful toxic solvents. The resulting nanoparticles were characterized by X-ray powder diffraction (XRD), field emission scanning electron microscopy (FESEM)-energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM), vibrating-sample magnetometer (VSM), thermogravimetry/differential thermal analysis (TG/DTA), and Brunauer–Emmett-Teller (BET). MTT assay was...
Application of magnetic sulfonated Alnus waste leaves as a heterogeneous catalyst for multi-component reactions; comparison and evaluation of acidity of eleven different leaves
, Article Reaction Kinetics, Mechanisms and Catalysis ; Volume 135, Issue 2 , 2022 , Pages 811-833 ; 18785190 (ISSN) ; Daneshfar, M ; Sharif University of Technology
Springer Science and Business Media B.V
2022
Abstract
A comprehensive study was carried out for the first time on the acidity of eleven different leaves. After functionalization of the leaves with –SO3H groups, the most acidic one was magnetized using nickel ferrite nanoparticles. This novel, inexpensive, green and biodegradable catalyst showed high activity in the synthesis of pyrazoline and 2-amino nicotinonitriles. Some compounds are new and have never been synthesized before and confirmed by FT-IR, 1H NMR and 13C NMR analysis. All of these compounds possess multiple biological activities. The heterogeneous magnetic catalyst (NiFe2O4-Alnus-SO3H) was characterized by various physicochemical techniques such as FT-IR spectroscopy, field...
Non-isothermal pyrolysis of used lubricating oil and the catalytic effect of carbon-based nanomaterials on the process performance
, Article Journal of Thermal Analysis and Calorimetry ; Volume 139, Issue 2 , 2020 , Pages 1025-1036 ; Abdoli, M. A ; Khorasheh, F ; Bayandori Moghaddam, A ; Sharif University of Technology
Springer Netherlands
2020
Abstract
Pyrolysis is a commonly used method for the recovery of used lubricating oil (ULO), which should be kinetically improved by a catalyst, due to its high level of energy consumption. In this research, the catalytic effects of carbon nanotube (CNT) and graphene nanoplatelets on the pyrolysis of ULO were studied through thermogravimetric analysis. First, the kinetic parameters of ULO pyrolysis including activation energy were calculated to be 170.12 and 167.01 kJ mol−1 by FWO and KAS methods, respectively. Then, the catalytic effects of CNT and graphene nanoplatelets on pyrolysis kinetics were studied. While CNT had a negligible effect on the pyrolysis process, graphene nanoplatelets...
Study on the Preparation and Properties of Polyamide/Chitosan Nanocomposite Fabricated by Electrospinning Method
, Article Journal of Polymers and the Environment ; 2021 ; 15662543 (ISSN) ; Fazeli, F ; Nuge, T ; Abdoli, O ; Moghaddam, S ; Sharif University of Technology
Springer
2021
Abstract
The principal intention of this work is to fabricate and characterize the polyamide/chitosan nanocomposite by a novel single solvent method through the electrospinning procedure. The thermal properties and morphology of prepared nanocomposite are studied by thermogravimetric analysis (TGA) and field-emission scanning electron microscopy (FE-SEM). TGA exposed that the primary decomposition temperature is reduced with rising of chitosan content in the nanocomposites and origin disintegration temperature for polyamide/chitosan nanocomposites is perceived to be in the range from 300 to 500 °C. Also, FE-SEM images demonstrated that the nanofibers of chitosan have good adhesion on the matrix and...