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Fabrication and evaluation of chitosan/gelatin/PVA hydrogel incorporating honey for wound healing applications: An in vitro, in vivo study
, Article International Journal of Pharmaceutics ; 2020 ; Aghababaie, Z ; Afjoul, H ; Jami, M ; Bidgoli, M. R ; Vossoughi, M ; Ramazani, A ; Kamyabhesari, K ; Sharif University of Technology
Elsevier B.V
2020
Abstract
In this study, physically cross-linked hydrogels were developed by freezing-thawing method while different concentrations of honey were included into the hydrogels for accelerated wound healing. The hydrogel was composed of chitosan, polyvinyl alcohol (PVA), and gelatin with the ratio of 2:1:1 (v/v), respectively. Further, the effect of honey concentrations on antibacterial properties, and cell behavior was investigated. In vivo studies, including wound healing mechanism using rat model and histological analysis of section tissue samples were performed. The results illustrated that the incorporation of honey in hydrogels increased the ultimate strain of hydrogels approximately two times,...
Improvement in flux and antifouling properties of PVC ultrafiltration membranes by incorporation of zinc oxide (ZnO) nanoparticles
, Article Separation and Purification Technology ; Volume 156 , 2015 , Pages 299-310 ; 13835866 (ISSN) ; Vatanpour, V ; Davood Abadi Farahani, M. H ; Zarrabi, H ; Sharif University of Technology
Elsevier
2015
Abstract
In this study, modification of polyvinyl chloride (PVC) ultrafiltration membranes with zinc oxide (ZnO) nanoparticle addition was taken into consideration. The ZnO at five different weights was added to the polymeric solution, and the membranes were fabricated by the phase inversion method using water as a nonsolvent and PEG 6 kDa as a pore former additive. The results showed that the pure water flux of the modified membranes increased up to 3 wt% ZnO addition, which was the optimized amount of the nanoparticle addition in this study. Also, at 3 wt% ZnO addition, flux recovery ratio reached from 69% to above 90%, indicated that the nanocomposite membranes were less susceptible to be fouled....
Enhancing sonocatalytic properties of TiO2 nanocatalysts by controlling the surface conditions: effect of particle size and PVA modification
, Article Desalination and Water Treatment ; Volume 57, Issue 58 , 2016 , Pages 28378-28385 ; 19443994 (ISSN) ; Madaah Hosseini, H. R ; Ordikhani, F ; Mokhtari Dizaji, M ; Sharif University of Technology
Taylor and Francis Inc
2016
Abstract
The influence of particle size and surface modification on sonocatalytic activity of TiO2 nanoparticles was investigated by measuring the degradation efficiency of methyl orange (MO) as a model pollutant. Crystalline TiO2 nanoparticles with different particles and aggregate size were prepared through solution-phase method with varying synthesis temperatures. Coating with polyvinyl alcohol was performed to enhance colloidal stability of the particles over a wide range of pH values (1.5–7.5). Characterization was carried out using X-ray diffraction, high-resolution transmission electron microscopy, dynamic light scattering, and Fourier-transformed infrared techniques. It was found that...
Poly(vinyl alcohol)/graphene oxide mixed matrix membranes for pervaporation of toluene and isooctane
, Article Polymer - Plastics Technology and Engineering ; Volume 56, Issue 12 , 2017 , Pages 1286-1294 ; 03602559 (ISSN) ; Mohebbi, V ; Behbahani, R. M ; Ahmad Ramazani, S. A ; Sharif University of Technology
Abstract
Poly(vinyl alcohol)/graphene oxide mixed matrix membranes have been prepared and applied for the pervaporation of isooctane (aliphatic) and toluene (aromatic) mixtures. Characteristics of the membranes such as crystallinity, morphology, and swelling have been investigated, and the results have been used to describe pervaporation performance. Experimental tests evidenced that incorporation of low content of graphene oxide nanoplates (0.5 wt%) in poly(vinyl alcohol) increases affinity of the membrane to aromatics by S and π bonds and selectivity increase to about four times. Moreover, interaction of graphene oxide with toluene results in increasing of swelling and decreasing of permeation...
Polyvinyl alcohol and polyvinyl alcohol/ polyvinyl pyrrolidone biomedical foams crosslinked by gamma irradiation
, Article Journal of Cellular Plastics ; Volume 53, Issue 4 , 2017 , Pages 359-372 ; 0021955X (ISSN) ; Frounchi, M ; Dadbin, S ; Sharif University of Technology
SAGE Publications Ltd
2017
Abstract
Foams for biomedical applications were made from polyvinyl alcohol, polyvinyl alcohol / polyvinyl pyrrolidone blend and their nanocomposites with nanoclay by clean processes. Air was entrapped into the aqueous polymer solutions during vigorous mixing and then the solutions were freeze-dried. The foams structure was stabilized by crosslinking via gamma irradiation without using any harmful chemicals. The hydrophilic biocompatible foams possessed interconnected open cell structure with remarkable capacity to absorb and retain water. The foams in wet state were soft and flexible. Desirable pore structure and higher water absorption was obtained at a solution concentration of 5 wt% for both...
Preparation of poly(vinyl chloride) (PVC) ultrafiltration membranes from PVC/additive/solvent and application of UF membranes as substrate for fabrication of reverse osmosis membranes
, Article Journal of Applied Polymer Science ; Volume 135, Issue 21 , 2018 ; 00218995 (ISSN) ; Asadollahi, M ; Musavi, A ; Bastani, D ; Sharif University of Technology
John Wiley and Sons Inc
2018
Abstract
Ultrafiltration (UF) membranes were prepared from poly(vinyl chloride) (PVC) as main polymer, poly(vinyl pyrrolidone) (PVP) as additive, and 1-methyl-2-pyrrolidone (NMP) as solvent using Design Expert software for designing the experiments. The membranes were characterized by SEM, contact angle measurement, and atomic force microscopy. The performance of UF membranes was evaluated by pure water flux (PWF) and blue indigo dye particle rejection. In addition, the molecular weight cutoff of UF membranes was determined by poly(ethylene glycol) (PEG) rejection. The UF membranes were used as substrates for fabrication of polyamide thin film composite (TFC) reverse osmosis (RO) membranes. The...
In situ emulsion polymerization and characterization of PVAc nanocomposites including colloidal silica nanoparticles for wood specimens bonding
, Article Journal of Applied Polymer Science ; Volume 137, Issue 15 , 2020 ; Ramezani Saadat Abadi, A ; Haddadi, S. A ; Ghaderi, S ; Azamian, F ; Sharif University of Technology
John Wiley and Sons Inc
2020
Abstract
Polyvinyl acetate (PVAc) nanocomposites for wood adhesives containing different amounts of colloidal silica nanoparticles (CSNs) were synthesized via in situ one-step emulsion polymerization. The adhesion strength of wood specimens bonded by PVAc nanocomposites was investigated by the tensile test. Thermal properties of PVAc nanocomposites were also characterized by differential scanning calorimetry and thermogravimetric analysis. Rheological and morphological properties of the PVAc nanocomposites were investigated using rheometric mechanical spectrometry and field emission scanning electron microscopy (FESEM), respectively. The obtaining results showed that the shear strength of PVAc...
Carbon-based nanocomposites: Distinguishing between deep-bed filtration and external filter cake by coupling core-scale mud-flow tests with computed tomography imaging
, Article Journal of Natural Gas Science and Engineering ; Volume 105 , 2022 ; 18755100 (ISSN) ; Fouji, M ; Ghorbani Heidarabad, R ; Aghaei, H ; Hajiabadi, S. H ; Bedrikovetsky, P ; Mahani, H ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Although Multi-Walled Carbon NanoTubes (MWCNTs) are found to influence the rheological behavior of drilling fluids, there are yet some controversies regarding their performance towards reducing formation damage induced by the invasion of water-based drilling fluids (WBFs). To address this important question, we synthesized novel nanocomposite materials via modifying the MWCNT via varying the proportion of carboxylated MWCNTs to PolyVinyl Alcohol (PVA). These nanocomposites were then used to make nano-based drilling-fluids (NDFs). The performance of the NDFs was evaluated by a set of rheological behavior tests, filtration experiments, and core-scale mud flow tests. To distinguish between the...
Dye Removal from Textile Effluent Using Membrane Process
, M.Sc. Thesis Sharif University of Technology ; Borghei, Mehdi (Supervisor)
Abstract
Textile industry is one of the biggest consumers of water in the world. Effluents of textile industry ordinarily have huge rate of dye compounds which are toxic and persistent in environment. In case which they did not treat and discharged in the environment, they can create cancer, poisoning and etc. Finding efficient, economic and fast method for treating of these effluents is an important factor on the management. Combination of ultrafiltration membrane and reverse osmosis processes, has taken into consideration as an efficient and fast method of treatment of textile effluents in recent years. One of the fundamental problems of this process is the high costs of operation and chemical...
Preparing an Appropriate UF Membrane from PVC to Use it as Substrate in Sea Water Desalination RO Membranes
, M.Sc. Thesis Sharif University of Technology ; Bastani, Daruoosh (Supervisor) ; Musavi, Abbas (Supervisor)
Abstract
In this study the main goal is preparing an appropriate UltraFiltration membrane from PolyVinyl Chloride for using as substrate in producing efficient Reverse Osmosis membranes to use in sea water desalination. each membrane should have some specifications to use it as reverse osmosis membrane’s substrate. One of the most important specifications is the appropriate pore sizes. To investigate this subject pure water flux and PolyEthylene glycol rejection of prepared membranes is tested. After investigation of this parameters and proving them, RO membranes are prepared using this membranes.
Salt rejection of Brackish water (2000ppm) and sea water (Persian gulf,32000ppm) are measured in...
Salt rejection of Brackish water (2000ppm) and sea water (Persian gulf,32000ppm) are measured in...
Cell life cycle effects of bare and coated superparamagnetic iron oxide nanoparticles
, Article Toxic Effects of Nanomaterials ; 2012 , Pages 53-66 ; 9781608054213 (ISBN) ; Laurent, S ; Journeay, W. S ; Sharif University of Technology
2012
Abstract
Due to the hopeful potential of nanoparticles in medicine, they have attracted much attention for various applications such as targeted drug/gene delivery, separation or imaging. Interaction of NPs with the biological environment can lead to a wide range of cellular responses. In order to have safe NPs for biomedical applications, the current biocompatibility researches are particularly focused on the severe toxic mechanisms which cause cells death. These mechanisms are apoptosis, autophagy and necrosis, which can also be intricately linked with the cell-life cycle, as there are various check-points and controls in a cell's life cycle to ensure appropriate division processes. Mechanisms by...
Pervaporation of toluene and iso-octane through poly(vinyl alcohol)/graphene oxide nanoplate mixed matrix membranes: Comparison of crosslinked and noncrosslinked membranes
, Article Journal of Applied Polymer Science ; Volume 135, Issue 7 , 2018 ; 00218995 (ISSN) ; Mohebbi, V ; Behbahani, R. M ; Ramazani S. A., A ; Sharif University of Technology
John Wiley and Sons Inc
2018
Abstract
Removal of aromatic compounds from fuel is an essential requirement in new environmental policies. In the present study, poly(vinyl alcohol)/graphene oxide (GO) mixed matrix membranes were prepared and applied to the separation of toluene from iso-octane by pervaporation, considering the similarity and interaction between graphene and aromatics. The effects of crosslinking and GO content on separation efficiency have been investigated in detail. Owing to the high affinity of GO with toluene through s and π bonds, the selectivity of the membranes was increased by incorporating a low amount of GO. The results also indicated that noncrosslinked membranes have higher selectivity and permeation...
Gas permeability measurement in polyethylene and its copolymer films
, Article Materials and Design ; Volume 28, Issue 9 , 2007 , Pages 2528-2532 ; 02613069 (ISSN) ; Razavi, J ; Mousavi, S. A ; Sharif University of Technology
Elsevier Ltd
2007
Abstract
In this research, low density polyethylene (LDPE) and poly(ethylene-co-vinyl acetate) (EVA) were used as polymeric materials. The methods used to produce LDPE and EVA was film blowing and thermal-dry phase inversion. The amount of permeability, diffusivity and solubility of O2 and CO2 through above polymers were obtained and also the effect of temperature, pressure and film thickness for LDPE was measured. To study film cross-section morphology in EVA, scanning electron microscopy (SEM) was applied. The results showed that the amount of permeability and solubility were decreased by increasing film thickness but diffusivity was increased. However, by increasing temperature, permeability,...
Numerical Analysis of Behavior of Concrete-Filled PVC Tubular Column
, M.Sc. Thesis Sharif University of Technology ; Khalou, Alireza (Supervisor)
Abstract
Concrete Filled Polyvinyl Chloride (PVC) Tube (CFCT) technique has attracted significant research attention in recent years. PVC offers a number of advantages such as low costs and excellent properties like 1- high electrical insulation; 2- high resistance for abrasion; 3- low diffusion for humidity; 4- remarkable resistance to water, bases, acids, alcohols, oils; 5- large elongation at break; 6- low creep deformation; 7- workability including (cutting); 8- consistency; and 9- excellent corrosion resistant, durability and mechanical stability. The PVC tube acts as a longitudinal and transverse reinforcement and serves as a formwork which simplifies construction and reduces erection time. The...
Antioxidant, antifungal, water binding, and mechanical properties of poly(vinyl alcohol) film incorporated with essential oil as a potential wound dressing material
, Article Journal of Applied Polymer Science ; Vol. 131, issue. 20 , 2014 ; Nateghpoor, B ; Dadfar, S. M. M ; Dadfar, S. M. A ; Sharif University of Technology
Abstract
In this study, the properties of poly (vinyl alcohol)(PVA) films incorporated with Zataria multiflora essential oil (ZMO) as a potential antioxidant/antibacterial material was investigated. PVA films were prepared from PVA solutions (2% w/v) containing different concentrations of ZMO. Water solubility, moisture absorption, water swelling, and water vapor permeability for pure PVA films were 57 ± 1.1, 99 ± 3.2%, 337 ± 8%, and 0.453 ± 0.015 g mm/m2 h, respectively. Incorporation of ZMO into PVA films caused a significant decrease in water swelling and moisture absorption and increase in solubility and water vapor permeability. Tensile strength, elastic modulus, and elongation at break for pure...
Evaluation of compressive and split tensile strength of slag based aluminosilicate geopolymer reinforced by waste polymeric materials using Taguchi method
, Article Materials Research Express ; Volume 8, Issue 2 , February , 2021 ; 20531591 (ISSN) ; Tayebi, M ; Shafiee, A ; Aghaie, A ; Sharif University of Technology
IOP Publishing Ltd
2021
Abstract
In this work, slag based aluminosilicate geopolymer was reinforced with polymeric fibers including, polyester (PES) (waste tire cap plies), polymeric particles including polyethylene terephthalate (PET) (waste water bottle), styrene-butadiene rubber (SBR) (waste tire), and polyvinyl chloride (PVC) (waste water hose). The tensile and compressive strength of the material was evaluated. Taguchi method was employed to assess the influence of the effective parameters on the mechanical characteristics of the geopolymer composite. QUALITEK-4 software was used to create the L32 orthogonal array with 192 (96+96) geopolymer specimens and 32+32 experiments. Analysis of variance (ANOVA) was utilized to...
Ionic liquids enhanced performance of PVC gels actuator
, Article Journal of Applied Polymer Science ; Volume 138, Issue 29 , 2021 ; 00218995 (ISSN) ; Latif, A ; Hussain, K ; Shehzad, F. K ; Ali, A ; Faisal, R ; Xudong, L ; Dias, O. A. T ; Weimin, Y ; Haoyi, L ; Sharif University of Technology
John Wiley and Sons Inc
2021
Abstract
Stimulated devices are highly demanded for actuators and artificial muscles in the recent era but susceptible to low deformation at an applied voltage. In the present work, ionic liquids (ILs) based gel films were prepared from the polyvinyl chloride (PVC), dibutyl adipate (DBA), 1-butyl, 3-methimidazolium chloride, and 1-pentyl-3-methylimidazolium hexafluorophosphate by a simple solvent evaporation method. The structural, morphological, optical, and mechanical properties of the composite PVC/ILs gel were characterized by Fourier-transform infrared spectroscopy (FTIR), Large Angle X-ray scattering (LAXS), UV–visible (UV–vis) absorption spectroscopy, scanning electron micrpscopy (SEM) and...
Ionic liquids enhanced performance of PVC gels actuator
, Article Journal of Applied Polymer Science ; Volume 138, Issue 29 , 2021 ; 00218995 (ISSN) ; Latif, A ; Hussain, K ; Shehzad, F. K ; Ali, A ; Faisal, R ; Xudong, L ; Dias, O. A. T ; Weimin, Y ; Haoyi, L ; Sharif University of Technology
John Wiley and Sons Inc
2021
Abstract
Stimulated devices are highly demanded for actuators and artificial muscles in the recent era but susceptible to low deformation at an applied voltage. In the present work, ionic liquids (ILs) based gel films were prepared from the polyvinyl chloride (PVC), dibutyl adipate (DBA), 1-butyl, 3-methimidazolium chloride, and 1-pentyl-3-methylimidazolium hexafluorophosphate by a simple solvent evaporation method. The structural, morphological, optical, and mechanical properties of the composite PVC/ILs gel were characterized by Fourier-transform infrared spectroscopy (FTIR), Large Angle X-ray scattering (LAXS), UV–visible (UV–vis) absorption spectroscopy, scanning electron micrpscopy (SEM) and...
Simulation and control of monomer conversion in a continuous emulsion polymerization reactor
, Article IFAC Proceedings Volumes (IFAC-PapersOnline), 7 June 2015 through 10 June 2015 ; Volume 48, Issue 8 , 2015 , Pages 315-320 ; 14746670 (ISSN) ; Shahrokhi, M ; Abedini, H ; Vafa, E ; Guay, M ; Gopaluni, B ; Huang, B ; Findeisen, R ; Sharif University of Technology
IFAC Secretariat
2015
Abstract
A detailed pseudo-bulk model has been used for prediction of conversion and particle size distribution (PSD) of vinyl acetate in a continuous emulsion polymerization reactor. Finite volume (FV) and moment techniques are applied for solving population balance equation under continuous operation. It is found that both methods can predict sustained oscillations in the monomer conversion, however the FV method matches the experimental data better than the moment method. The monomer conversion and free surfactant concentration are controlled via two single control loops. In this work, a new control strategy for controlling monomer conversion has been proposed. It has been shown that monomer...
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...