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polyvinylidene-fluoride
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Fabrication and Characterization of Modified Polyether Ether Ketone/Carbon Nanofiber Nanocomposite for Bone Application
, M.Sc. Thesis Sharif University of Technology ; Ramazani Saadatabadi, Ahmad (Supervisor)
Abstract
The use of polyether ether ketone (PEEK) in bone implants is limited due to a lack of cell adhesion and proliferation. Therefore, in this study, we modified the surface of PEEK with a nanocomposite coating containing piezoelectric and bioactive properties. Sulfonated PEEK with suitable mechanical and hydrophilic properties along with polyvinylidene fluoride was used as a biocompatible polymer with piezoelectric properties for coating. Also, nanohydroxyapatite was used as a bioactive material, and carbon nanofibers with significant mechanical and electrical properties were used in the nanocomposite. The surface was sulfonated as an intermediate layer to improve the connection between the...
Production of Mixed-Matrix Composite Membranes Based on Metal-Organic Framework/Polyvinylidene Fluoride for Desalination of High Saline Water in Membrane Distillation
, M.Sc. Thesis Sharif University of Technology ; Bastani, Dariush (Supervisor) ; Mousavi, Abbas (Supervisor)
Abstract
In this study, membrane distillation was used for desalination of high saline water. Recently, the synthesis of nanoparticles for the synthesis of membranes for membrane distillation has shown incredible improvement in the morphological properties, flux, and rejection. In this study, by incorporating UiO-66 functionalized with Palmitic acid into PVDF/PEG polymer solution we could improve membranes properties. Functionalization of UiO-66 with Palmitic acid was confirmed with FTIR, XRD, BET, SEM. In the membrane containing 3% Palmitic acid-UiO-66, the flux was increased by 46.5%, resulting in a flux of 12.6 LMH, and the salt rejection was improved from 99.5% to 99.9%. These results confirmed...
Electron beam induced modifications in crystalline structure of polyvinylidene fluoride/nanoclay composites
, Article Radiation Measurements ; Vol. 60 , January , 2014 , pp. 1-6 ; ISSN: 13504487 ; Dadbin, S ; Frounchi, M ; Sharif University of Technology
Abstract
PVDF/nanoclay nanocomposites were prepared via melt mixing method. The intercalated dispersion of the nanoclay in PVDF matrix was confirmed by XRD. According to FTIR, DSC and XRD results, the presence of nanoclay facilitated transition from α-to-β crystalline phase. Electron beam irradiation decreased the melting point of the nanocomposites. The decrease in melting point of the nanocomposites was about 11 C at 500 kGy. The crystallinity of nanocomposites increased at an irradiation dose of 100 kGy and decreased at higher irradiation doses. The extent of crosslinking of the nanocomposites increased significantly with irradiation up to 300 kGy. The nanoclay intensified the increase in yield...
Characterization of PVDF/Nanoclay Nanocomposites Prepared by Melt, Solution, and Co-Precipitation Methods
, Article International Journal of Polymer Analysis and Characterization ; Volume 17, Issue 4 , 2012 , Pages 291-301 ; 1023666X (ISSN) ; Dadbin, S ; Frounchi, M ; Sharif University of Technology
2012
Abstract
Poly (vinylidene fluoride) (PVDF) nanocomposites were prepared via melt, solution, and co-precipitation mixing methods using Cloisite 30B as organoclay. The results from X-ray diffraction patterns display intercalation or exfoliation of nanoclay depending on the nanocomposite preparation method. The solvent cast and co-precipitated samples showed exfoliation, while intercalation was observed in the nanocomposites prepared by melt mixing. Introducing organoclay induced formation of β-crystals in the PVDF nanocomposites as evidenced by XRD and FT-IR. FT-IR analysis indicated that the samples prepared by the co-precipitation method had a higher tendency for β phase formation, while the sample...
Gellan gel comprising short PVDF based-nanofibers: The effect of piezoelectric nanofiber on the mechanical and electrical behavior
, Article Materials Today Communications ; Volume 26 , 2021 ; 23524928 (ISSN) ; Ramazani S. A., A ; H-Shirazi, F ; Hassanzadeh Nemati, N ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Gel-fiber structure with the potential of extracellular matrix (ECM) mimics can be introduced as a suitable candidate for bioengineering applications. In this study, piezoelectric gellan gel-fiber was prepared with incorporating poly(vinylidenefluoride) (PVDF)/glass-flake in the gellan matrix. Glass-flake nanoparticles were modified with silane group, PVDF/glass-flake nanofibers were synthesized and short-strand nanofibers were fabricated using the mechanical homogenizer method. Brunauer–Emmett–Teller (BET), Fourier-transform infrared spectroscopy (FTIR), and Thermogravimetric analysis (TGA) analyses were used for surface modification study, and scanning electron microscopy (SEM),...
Superhydrophobic dual layer functionalized titanium dioxide/polyvinylidene fluoride-co-hexafluoropropylene (TiO2/PH) nanofibrous membrane for high flux membrane distillation
, Article Journal of Membrane Science ; Volume 537 , 2017 , Pages 140-150 ; 03767388 (ISSN) ; Rabiee, H ; Seyedi, S. M ; Mokhtare, A ; Brant, J. A ; Sharif University of Technology
Elsevier B.V
2017
Abstract
In this study, superhydrophobic dual layer membranes with highly porous structure were fabricated using electrospinning and electrospraying techniques. Electrospinning method was used to produce the support nanofibrous layer using polyvinylidene fluoride-co-hexafluoropropylene (PH) as the polymer and a mixed solvent system of N,N-Dimetylformamide (DMF) and acetone. Afterwards, hydrophobic, functionalized TiO2 nanoparticles were deposited on the surface of the support layer using the electrospraying technique. TiO2 chemical functionalization and their deposition on the support layer were investigated by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy. The...
Construction of New Polymer Electrolyte Based on PVDF-HFP, Plasticizer DMA AndSiO2nano-particles with High Ionic Conductivity for Lithium Batteries
, M.Sc. Thesis Sharif University of Technology ; Baghalha, Morteza (Supervisor) ; Khorasheh, Farhad (Supervisor)
Abstract
Polymer electrolytes are most frequently used electrolytes especially in lithium ion batteries. The gel-polymer and polymer-ceramic electrolytes were synthesized using DMA plasticizer, LiClO4, and SiO2 ceramic Nano fillers through coating method. EIS, FTIR, XRD, SEM, and TGA analyses were carried out on electrolytes. The optimum amount of perchlorate and polymer was obtained 0.5 M and 5% w/w, respectively. Also, the optimum amount of silica was obtained 2% w/w. the optimizations were carried out suing conductometry. The EIS analysis showed the ionic conductance of gel-polymer 1.8 mS.cm-1 while that of ceramic-polymer was obtained 2.8 mS.cm-1
Advanced gel polymer electrolyte for lithium-ion polymer batteries
, Article ASME 2013 7th Int. Conf. on Energy Sustainability Collocated with the ASME 2013 Heat Transfer Summer Conf. and the ASME 2013 11th Int. Conf. on Fuel Cell Science, Engineering and Technology ; July , 2013 ; 9780791855515 (ISBN) ; Hashemi, N ; Ashuri, M ; Montazami, R ; Advanced Energy Systems Division, Solar Energy Division ; Sharif University of Technology
2013
Abstract
We report improved performance of Li-ion polymer batteries through advanced gel polymer electrolytes (GPEs). Compared to solid and liquid electrolytes, GPEs are advantageous as they can be fabricated in different shapes and geometries; also ionic properties are significantly superior to that of solid and liquid electrolytes. We have synthetized GPE in form of membranes by trapping ethylene carbonate and propylene carbonate in a composite of polyvinylidene fluoride and N-methylpyrrolidinore. By applying phase-transfer method, we synthetized membranes with micro-pores, which led to higher ionic conductivity. The proposed membrane is to be modified further to have higher capacity, stronger...
Magnetoelectric nanocomposite scaffold for high yield differentiation of mesenchymal stem cells to neural-like cells
, Article Journal of Cellular Physiology ; Volume 234, Issue 8 , 2019 , Pages 13617-13628 ; 00219541 (ISSN) ; Soleimani, M ; Ghiass, M. A ; Hatamie, S ; Vakilian, S ; Zomorrod, M. S ; Sadeghzadeh, N ; Vossoughi, M ; Hosseinzadeh, S ; Sharif University of Technology
Wiley-Liss Inc
2019
Abstract
While the differentiation factors have been widely used to differentiate mesenchymal stem cells (MSCs) into various cell types, they can cause harm at the same time. Therefore, it is beneficial to propose methods to differentiate MSCs without factors. Herein, magnetoelectric (ME) nanofibers were synthesized as the scaffold for the growth of MSCs and their differentiation into neural cells without factors. This nanocomposite takes the advantage of the synergies of the magnetostrictive filler, CoFe 2 O 4 nanoparticles (CFO), and piezoelectric polymer, polyvinylidene difluoride (PVDF). Graphene oxide nanosheets were decorated with CFO nanoparticles for a proper dispersion in the polymer through...
Sustained release of CIP from TiO2-PVDF/starch nanocomposite mats with potential application in wound dressing
, Article Journal of Applied Polymer Science ; Volume 137, Issue 30 , 2020 ; Haddadi, S. A ; Amini, M ; Hasany, M ; Ramazani SaadatAbadi, A ; Sharif University of Technology
John Wiley and Sons Inc
2020
Abstract
Electrospinning is an economical and alluring method to fabricate wound dressing mats from a variety of natural and synthetic materials. In this study, polyvinylidene fluoride (PVDF) and starch composite mats containing ciprofloxacin (CIP) loaded on titanium dioxide nanoparticles (TiO2) were prepared. Fourier Transform Infrared spectra of CIP, synthesized TiO2 NPs, TiO2/CIP, and PVDF/starch composite mats are analyzed. Scanning electron microscopy images revealed that the fiber diameter of PVDF nanofibers thickens by increasing starch, which varies between 180 nm and 550 nm. Strain at break of PVDF, starch, PVDF/starch (2:1 w:w; P2S1), PVDF/starch (1:1 w:w; P1S1), PVDF/starch (1:2 w:w;...
Gellan gel comprising short PVDF based-nanofibers: the effect of piezoelectric nanofiber on the mechanical and electrical behavior
, Article Materials Today Communications ; 2020 ; Ramazani Saadat Abadi, A ; Shirazi, F. H ; Hassanzadeh Nemati, N ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Gel-fiber structure with the potential of extracellular matrix (ECM) mimics can be introduced as a suitable candidate for bioengineering applications. In this study, piezoelectric gellan gel-fiber was prepared with incorporating poly(vinylidenefluoride) (PVDF)/glass-flake in the gellan matrix. Glass-flake nanoparticles were modified with silane group, PVDF/glass-flake nanofibers were synthesized and short-strand nanofibers were fabricated using the mechanical homogenizer method. Brunauer–Emmett–Teller (BET), Fourier-transform infrared spectroscopy (FTIR), and Thermogravimetric analysis (TGA) analyses were used for surface modification study, and scanning electron microscopy (SEM),...
Metal organic framework nanoparticles loaded- PVDF/chitosan nanofibrous ultrafiltration membranes for the removal of BSA protein and Cr(VI) ions
, Article Journal of Molecular Liquids ; Volume 317 , 2020 ; Koushkbaghi, S ; Hosseini, S. S ; Darabi, M ; Yousefi, A ; Irani, M ; Sharif University of Technology
Elsevier B.V
2020
Abstract
The UiO-66 NH2 and ZIF-8 metal organic framework nanoparticles (NMOFs) were incorporated into the polyvinylidene fluoride (PVDF) nanofibrous membrane. Then, the chitosan nanofibers were coated on the PVDF nanofibers to produce the PVDF/chitosan nanofibers. The performance of synthesized PVDF/NMOFs single layer and PVDF/chitosan/NMOFs two layers nanofibrous membranes was investigated for BSA protein molecules and Cr(VI) ions separation via ultrafiltration membrane process. The potential of synthesized nanofibers was also examined for BSA and Cr(VI) adsorption in a batch system. The characteristics of synthesized nanofibrous membranes were determined using SEM, EDX, TGA, BET, porosity and...
PVDF/PU blend membrane separator for lithium-ion batteries via non-solvent-induced phase separation (NIPS)
, Article Journal of Solid State Electrochemistry ; Volume 25, Issue 8-9 , 2021 , Pages 2385-2394 ; 14328488 (ISSN) ; Fathollahi Zonouz, A ; Soltanieh, M ; Mousavi, S. A ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2021
Abstract
Membrane separator based on the polyvinylidene fluoride (PVDF) is prepared via the non-solvent-induced phase separation (NIPS) method with water and ethanol as non-solvent and a mixture of dimethylformamide (DMF) and acetone as solvent. The effect of various acetone/DMF ratios and non-solvent material on the physical and electrochemical properties of the separator is studied by FE-SEM, tensile strength, electrochemical AC-impedance spectroscopy (EIS), thermal stability, and linear sweep voltammetry (LSV). The charge-discharge studies are carried out by fabricating a lithium foil/polymer electrolyte membrane/LiFePO4 cell. The results show that with the change of solvent and non-solvent, the...
ZnO-incorporated polyvinylidene fluoride/poly(ε-caprolactone) nanocomposite scaffold with controlled release of dexamethasone for bone tissue engineering
, Article Applied Physics A: Materials Science and Processing ; Volume 128, Issue 8 , 2022 ; 09478396 (ISSN) ; Mohammadi, M ; Mashayekhan, S ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2022
Abstract
Here we report on the development of a hybrid nanofibrous scaffold made from polyvinylidene fluoride (PVDF) nanofibers embedding zinc oxide nanorods (ZnOns), and poly(ε-caprolactone) (PCL) nanofibers incorporating dexamethasone (DEX)-loaded chitosan nanoparticles using dual-electrospinning method. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and tensile analysis were carried out for physiochemical characterization of the scaffolds, followed by DEX release profile. In addition, an MTT assay was conducted to assess the viability of mouse bone marrow-derived mesenchymal stem cells (mBMSCs) on the hybrid nanofibrous scaffold....
Cold atmospheric plasma modification and electrical conductivity induction in gelatin/polyvinylidene fluoride nanofibers for neural tissue engineering
, Article Artificial Organs ; Volume 46, Issue 8 , 2022 , Pages 1504-1521 ; 0160564X (ISSN) ; Hosseini, E ; Ramazani Saadatabadi, A ; Atyabi, S ; Bakhshandeh, H ; Mohamadali, M ; Aidun, A ; Farasati Far, B ; Sharif University of Technology
John Wiley and Sons Inc
2022
Abstract
Background: This research follows some investigations through neural tissue engineering, including fabrication, surface treatment, and evaluation of novel self-stimuli conductive biocompatible and degradable nanocomposite scaffolds. Methods: Gelatin as a biobased material and polyvinylidene fluoride (PVDF) as a mechanical, electrical, and piezoelectric improvement agent were co-electrospun. In addition, polyaniline/graphene (PAG) nanoparticles were synthesized and added to gelatin solutions in different percentages to induce electrical conductivity. After obtaining optimum PAG percentage, cold atmospheric plasma (CAP) treatment was applied over the best samples by different plasma variable...
Beyond hierarchical mixed nickel-cobalt hydroxide and ferric oxide formation onto the green carbons for energy storage applications
, Article Journal of Colloid and Interface Science ; Volume 593 , 2021 , Pages 182-195 ; 00219797 (ISSN) ; Hekmat, F ; Shahrokhian, S ; Sharif University of Technology
Academic Press Inc
2021
Abstract
To attain superior energy density concurrently with high power density, high-performance supercapacitors have been developed. Herein an innovative strategy has been adopted to fabricate unique binder-free electrodes composed of a unique porous structure of binary metal carbonate hydroxide nanomace-decorated hydrothermal porous carbon spheres (PCSs). Hierarchical nickel-cobalt carbonate hydroxide (NiCOCH) nanomaces, directly grown on PCSs, are used as positive electrodes for supercapacitors fabrication. Furthermore, Fe2O3@PCS composites, having benefits of highly reversible redox reaction in the negative potential window and highly porous structure, are employed as the negative electrode in...
Beyond hierarchical mixed nickel-cobalt hydroxide and ferric oxide formation onto the green carbons for energy storage applications
, Article Journal of Colloid and Interface Science ; Volume 593 , 2021 , Pages 182-195 ; 00219797 (ISSN) ; Hekmat, F ; Shahrokhian, S ; Sharif University of Technology
Academic Press Inc
2021
Abstract
To attain superior energy density concurrently with high power density, high-performance supercapacitors have been developed. Herein an innovative strategy has been adopted to fabricate unique binder-free electrodes composed of a unique porous structure of binary metal carbonate hydroxide nanomace-decorated hydrothermal porous carbon spheres (PCSs). Hierarchical nickel-cobalt carbonate hydroxide (NiCOCH) nanomaces, directly grown on PCSs, are used as positive electrodes for supercapacitors fabrication. Furthermore, Fe2O3@PCS composites, having benefits of highly reversible redox reaction in the negative potential window and highly porous structure, are employed as the negative electrode in...
Efficient protein immobilization on polyethersolfone electrospun nanofibrous membrane via covalent binding for biosensing applications
, Article Materials Science and Engineering C ; Volume 58 , 2016 , Pages 586-594 ; 09284931 (ISSN) ; Soudi, S ; Soleimani, M ; Hosseinzadeh, S ; Esmaeili, E ; Vossoughi, M ; Sharif University of Technology
Elsevier Ltd
2016
Abstract
In this paper we introduce novel strategy for antibody immobilization using high surface area electrospun nanofibrous membrane based on ethyl-3-(3-dimethylaminopropyl)-carbodiimide/N-hydroxysuccinimide (EDC/NHS) coupling chemistry. To present the high performance of proposed biosensors, anti-staphylococcus enterotoxin B (anti-SEB) was used as a model to demonstrate the utility of our proposed system. Polymer solution of polyethersolfone was used to fabricate fine nanofibrous membrane. Moreover, industrial polyvinylidene fluoride membrane and conventional microtiter plate were also used to compare the efficiency of antibody immobilization. Scanning electron microscopy images were taken to...
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 ; Volume 167 , 2021 , Pages 881-893 ; 01418130 (ISSN) ; S. A., A. R ; H Shirazi, F ; Nemati, N. H ; Sharif University of Technology
Elsevier B.V
2021
Abstract
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...
Design of an effective piezoelectric microcantilever biosensor for rapid detection of COVID-19
, Article Journal of Medical Engineering and Technology ; Volume 45, Issue 6 , 2021 , Pages 423-433 ; 03091902 (ISSN) ; Merati, M ; Abdekhodaie, M. J ; Sharif University of Technology
Taylor and Francis Ltd
2021
Abstract
Acute respiratory syndrome coronavirus 2 (SARS-CoV-2), also called COVID-19, is one of the most contagious viruses resulting in a progressive pandemic. Since specific antiviral treatments have not been developed yet and its fatal rate is almost high, early and fast detection is critical for controlling the outbreak. In this study, a piezoelectric microcantilever biosensor has been designed for detecting COVID-19 samples directly without requiring preparation steps. The biosensor acts as a transducer and is coated with the related antibody. When the SARS-CoV-2 antigens adsorbed on the microcantilever top surface through their spike proteins, a surface stress due to the mass change would be...