Sharif Digital Repository

In this research, polypropylene and propylene- ethylene copolymers were synthesized and propylene- ethylene copolymer Graphene Oxide Nano composites were prepared via solution mixing method. Nano Graphene Oxide sheets were synthesized utilizing modified hummer’s method. Ziegler Natta catalyst system was a complex of Magnesium Ethoxide as the support of the catalyst and Titanium tetra Chloride as the catalyst. Tri iso Butyl Aluminum (TiBA) and Tri Ethyl Aluminum (TEAl) were used as co catalyst. FT-IR and XRD patterns show well oxidation of graphite sheets and fragmentations of them. FESEM images clear the successfulness of copolymerization and also well-dispersion and distribution of Nano... 

In this research polypropylene/carbon nanotube nano composites were prepared via in situ polymerization using Bi-supported Ziegler-Natta catalytic systems. Magnesium etoxide and Multi wall carbon nanotubes(MWCNT) functionalized by hydroxyl groups were used as supports of catalyst. TiCl4 and TiBA were used as catalyst and co catalyst respectively. After defining the polymerization optimum conditions and considering its parameters constant, nano composites with different carbon nanotube contents were produced by changing the polymerization time. Scanning Electron Microscopy (SEM) images certified very good dispersion of MWCNTs throughout polypropylene matrix. The thermal properties behavior of... 

In this work, sulfonated polycarbonate (SPC ) membranes with different acid contents have been prepared by conducting sulfonation reaction at room temperature using Chlorosulfonic acid (CSA) as sulfonating agent at different concentration of acid in reacting solution. The SPC membranes were obtained by casting from 10% solution of SPC in chloroform at room temperature. The prepared membranes were characterized using Ion exchange capacity (IEC), and degree of sulfonation (DS), Fourier Transform Infrared (FTIR), NMR spectra, Thermal Gravimetric Analysis (TGA) and Water uptake. The obtained results showed that with increaseing in Chlorosulfonic acid content in sulfonation reaction IEC and DS of... 

Fixation devices and implants are the most applied devices in orthopedic operation and dentistry. Interference screw is one of these devices that is made by biodegradable nanocomposite polymeric materials in this project. The purpose of this project is designing interference screw, applicable to body, and doing related tests since in vivo tests. For this purpose, hand injection molding, was designed to prepare screws in laboratory scale, first. For making samples, poly(D,L) lacticacid, nano hydroxyapatite as reinforce and polyethylene glycol as plasticizer were used. These samples were made by combination of solvent casting and melt processing methods. Adding nano hydroxyapatite and... 

Wax precipitation is one of the major problems in the transfer of crude oil from field production to refineries. This wax with asphaltene compounds and some water and solids, closes the oil pipeline. One of the ways to reduce the amount of wax in pipes is to use additives (flow improvers) to crude oil and improve its rheological behavior. In this research, Five Iranian crude oils were characterized with SARA test and then the effects of various additives including ethylene vinyl acetate (EVA) in concentrations of 500 and 1500 ppm, alkyl phenol ormaldehyde resins (NPFR) with 1500 ppm and styrene-(ethylene-cobutylene)- styrene (SEBS) with 1500 ppm on viscosity, wax appearance temperature... 

The main object of this thesis is preparation and investigation of polyolophine/graphene oxide nanocomposites by using bi-supported Ziegler-Natta catalytic system and in-situ polymerization. Magnesium ethoxide and graphene oxide were used as supports of catalyst. TiCl4 was accompanied by triisobutyl aluminum (tibia) and diisobutyl phthalate (DIBP) as an electron donor constituting Ziegler-Natta catalytic system. Preparation of catalyst and polymerization were taken place in slurry phase under the argon atmosphere. At the beginning of the polymerization experiment, several type of nanocomposites were made under various conditions (such as different Al/Ti molar ratio) to find optimum condition... 

The nervous system is the most complex body system and controls other body systems. Damages of the peripheral nervous system will interfere with the functioning of the body. Tissue engineering is used as one of the most effective methods for repairing damaged tissues,by providing 3-dimensional (scaffold) bedding with proper properties, allows the proliferation of Myelin sheath and proliferation of axons. In this study, we used a continuous extrusion process, sodium alginate with different percentages of Polyaniline-Graphene nanoparticle (synthesized by solvent emulsion) was extruded and its properties were determined by FTIR, SEM, MTT, tensile properties, Conductivity, contact angles and... 

Although polyacrylamides and theirs modified polymers have an extremely application in the industry mechanical weakness, such as viscosity in salinity or high temperature cause this polymer loss your functional application. In recent years, many endeavors due as modified this polymer by hydrophobics monomers were done but unfortunately don’t have a significant result. Modified acrylamide monomer and hydrophobic mini-emulsion were survey Most used polymers, such as hydrolyzed polyacrylamide, are not able to high levels of salinity and high temperature of the reservoirs. Dr. Ramazani and theirs group use innovational idea of hydrophilic monomers for overcome to this problem. In this project,... 

The present work focuses on the sustainable development of an intelligent self-healing anticorrosion coating using nanocontainers based on the aluminium oxide nanostructure-pomegranate peel extract-Ce3+ (Ce-PPE@Cat). The Ce-PPE@Cat nanopigment was introduced into the epoxy film (Ep) to achieve a smart barrier/ self-healing anti-corrosive property. To this end, a couple of characterization tests, including FT-IR, TGA, and, BET have been carried out to investigate the Ce-PPE@Cat nanopigment structure/composition. The effectiveness of the anti-corrosion performance of the established coatings was confirmed by EIS, FE-SEM, and accelerated salt spray test. Furthermore, EIS studies revealed that... 

In recent years, the use of polyurethane foams has been of interest for many researchers and craftsmen. Polyurethane foams, due to their excellent properties, can be used in important applications such as advanced military industries, insulation and those requiring strength and maneuverability. The aim of this research project is to produce polyurethane / sodium silicate or nano-silica nanocomposites. Prior to the fabrication and synthesis process of polyurethane containing sodium or nano-silica, deposited silica nanoparticles were synthesized using high-rubbed sodium silicate and sulfuric acid, followed by various tests including XRD, FE-SEM and BET to verify It was done. Sodium silicate... 

With the rapid increase of energy consumption, energy problem has been a global issue, which must be faced with and solved. One way to prevent energy consumption is to reduce drag in the flow inside the pipes by using polymer additives; Because the Transportation of liquids using pipeline technology has its limitations, since turbulent flow inside the pipe involves a loss of energy. The net effect of this is that increasing the energy applied to the flow does not increase the flow rate. For this purpose, copolymers and terpolymers of hydrophilic acrylamide monomers along with hydrophobic styrene and hydrophilic maleic anhydride monomers were synthesized by reverse emulsion polymerization... 

The use of polymers in the EOR process is very common. Most of these polymers are sensitivity to temperature, salt, and the presence of bacteria. Among these materials, hydrolyzed polyacrylamide (HPAM) is the most widely used. Due to the sensitivity of HPAM in harsh conditions like temperature and salinity of the environment, modification of this polymer by hydrophobic groups can be very effective. Hydrophobic-hydrophilic associative polymers have shown unique rheological properties and high thermal stability, which is due to the presence of a small percentage (up to two percent) of hydrophobic monomers in their structure. Despite these excellent properties for acrylamide copolymers... 

Hydrophilic polymers are widely used in enhanced oil recovery (EOR) processes to increase water viscosity during polymer flooding. However, these polymers increase the viscosity of injected water in undesirable strands, before reaching considerable positions that make some problems in polymer flooding process such as thermal, mechanical, bacterial degradation, surface absorption and undesirable plugging. In this study, a novel core-shell structure of polyacrylamide as an active polymer and nanoscale coating polystyrene as a shell polymer was designed and prepared to intelligently control mobility ratio in oil reservoirs and overcome weakness and limitations of classical polymer flooding.... 

The main purpose of this study is simulation of in-situ release of nano-size coated polymer particles at the water-oil interface during the polymer flooding. Reaching at the flooding interface, the hydrophobic coating starts dissolving into the oil phase. Subsequently, the hydrophilic core polymer starts diffusing back and simultaneously solves into the water phase and increase the in-situ viscosity of the flooding interface. Because of the in-situ release of the polymer and consequently the viscosity reduction of the injected fluid, the driving force for injection of the polymer as well as the amount of polymer used in flooding will reduce. In addition, smart coating can decrease the... 

It is about half century passed from the invention and application of the polymer flooding. Although there are successful reports from the using polymer flooding, but there are problems that in some cases this process fails. For more insight on the problems and in order to improve
the efficiency of this process the conceptual understanding of the process is required. More conceptual understanding from this process, requires investigation in pore scale. In the presenting investigation, the flow of Newtonian and non-Newtonian fluids in the single phase and two phase form and in pore scale are simulated using finite volume method. Because, the finite volume method is used in very... 

Among the methods for increasing chemical oil extraction,the polymeric flood method has the most commercialization capability.However,most commonly used polymers such as Hydrolyzed Polyacrylamide (HPAM) are not able to withstand high levels of salinity and high temperatures.To overcome these problems,in this project,new types of polymer nanostructures were synthesized with hydrophobic groups consisting of styrene (hydrophilic monomer) and malic anhydride (hydrophilic monomer) acrylamide (hydrophilic monomer). These polymers were synthesized by reversible mini-emulsion by adjusting the synthesis conditions for the purpose of producing the terpolymer with suitable conditions for tolerating... 

In order to protect the corrosion of steel, a self-healing epoxy nanocomposite containing modified graphite carbon nitride (g-C3N4) and ZIF-67 was made along with benzotriazole (BTA) and cerium inhibitors. To increase the efficiency and also to increase the duration of use of inhibitors, it is better to load these inhibitors on containers such as MOFs. One of the useful MOFs for this purpose is ZIF-67, which has a high specific surface area that allows the transport of inhibitors with high capacity. But these containers fail after some time, so to improve the physical properties of the coating systems, g-C3N4 was also used as a mineral material, which of course was also used as a filler.... 

The main object of this thesis is production and investigation of polypropylene-fumed silica nanocomposites by using bi-supported Ziegler-natta catalytic system and in-situ polymerization. Magnesium ethoxide and fumed silica were used as supports of catalyst. TiCl4 was accompanied by triisobutyl aluminum(TiBA) and diisobutyl phthalate(DIBP) as electron doner constituting Ziegler-Natta catalytic system. Preparation of catalyst and polymerization were taken place in slurry phase under the argon atmosphere. At the beginning of the polymerization experiment, several type of nanocomposites were made under various conditions(such as different Al/Ti molar ratio) to find optimum condition to...