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Research Project Synthesis, Characterization And Applications Of Various Aromatic Polythioureas Via Multicomponent Polymerization/çok Bileşenli Polimerizasyon Yöntemi ile Farklı Aromatik Politiyoürelerin Sentezi, Karakterizasyonu ve UygulamalarıIn recent years, multicomponent polymerization (MCP) method has attracted the attention of researchers due to its simple operation, high atom economy, high polymerization efficiency and high molecular weight of polymers without using catalyst under moderate conditions. In the MCP method used in the synthesis of different polythioamides and polythioureas, one of the reactants is aliphatic amines and aromatic amines are not used directly. Due to this reason, in polythioamide syntheses, it is seen that aromatic diamines do not react with alkynes in the presence of elemental sulfur and therefore they are converted firstly to aromatic diisocyanides and this increases the cost of synthesis. There is no study on the use of aromatic diamines directly in the synthesis of polythioureas. In the light of this information, it is aimed to use the MCP method which is thought to be an economic and effective method for the use of elemental sulfur and aromatic diamine directly to obtain well defined, functional and workable polymeric structures without using catalyst in the project. In the MCP method, diisocyanides which are more reactive than the dialkyne reactant used previously will be used. The reactivity of diisocyanides to aromatic amines was supported by literature data and preliminary studies performed by our group. In addition, elemental sulfur, one of the most abundant elements in the world, is a non-toxic and stable solid under normal conditions and is an inexpensive substance that is readily available even at high purity grades. The use of aromatic diamines directly with elemental sulfur is very interesting in terms of practical, cost-effective and synthetic compatibility. With the use of aromatic diamines in the MCP method, the gateway for the synthesis of different polythioureas will be further expanded. For this purpose, the synthesis of 10 different polythioureas shown below will be carried out and characterization of the obtained products (NMR, FTIR, GPC, SEM, UV-Vis, DSC, TGA) will be performed. The data obtained will be examined comparatively with the methods used before for the synthesis of polythioureas. Due to today's polluted environment and limited energy reserves, it becomes important to develop highly efficient renewable technologies, green energy sources and environmentally friendly methods for environmental remediation and energy production. In this direction, hydrogen production becomes so important in the field of energy. In addition, the removal of heavy metals found in nature and organic matter in waste water is of great importance in environmental remediation. From this point of view, the preparation of nanocatalysts that will allow hydrogen production and removal of organic substances and materials that provide heavy metal removal attracts the attention of scientists. Thanks to the thiourea functional groups in the structure of different polythioureas to be synthesized by the MCP method, it can be used in mercury treatment (due to the ability of the thiourea groups and mercury ions to be complex) as well as to be used as support materials for the production of silver, palladium and copper nanoparticles. In this respect, firstly mercury removal capacity of the prepared polymers will be investigated. Then, the polymer-metal nanoparticle hybrid materials (4 different structures, polymer/AuNPs, polymer/AgNPs, polymer/CuNPs and polymer/PdNPs)) will be obtained by adding gold, silver, copper and palladium nanoparticles (separately) onto the polymer having the highest metal ion-holding capacity. The stability, catalytic activity and the effect of the interaction on the catalytic activity of the polymer/metal nanoparticle hybrid materials will be investigated in hydrogeneration from amine borane and photocatalytical removal of dye molecules founded in waste waters, respectively.Research Project Synthesis and Applications of New Conjugated Polymeric Materials Based on CarboraneCombination of conjugated polymers and carborane units under the same roof was taken place recently, for the first time in 2003. In very few number of studies in the literature, it was reported that carborane units gave thermal, mechanical, optical and electrochemical stability to the condujugated polymers. In this study, in order to overcome the problems faced by the industrial field of conjugated polymers (insolubility, thermal, mechanical, optical and electrochemical instability, etc.) the inorganic and organic units will be melted in the same pot for producing new carborane based polymeric materials. In the first two years of the project, initially carborane based electron donor-acceptor-donor (D-A-D) type new inorganic-organic hybrid monomers will be designed and synthesized and then soluble conjugated polymers (low band gap, reversible electronic and optical properties, n- and/or p-type doping behavior, fast switching of various redox states and different colors and environmetally and thermally stable novel florescent conjugated polymers) will be tried to obtain by use of electrochemical and chemical methods. While alkyl substituted 3,4-propylenedioxythiophene and carbazole units will be used as D unit, carborane units will be used as A unit. Tetrabutylammonium salts (perchlorate, tetrafluoroborate and hexafluorophosphate) as the supporting electrolyte and acetonitrile, dichloromethane and/or propylene carbonate will be used as the solvent in the electrochemical polymerization. For the chemical polymerization, Stille Coupling, anhydrous FeCl3 and / or CuI oxidant and/or Yamamoto type Ni (0) dehalogenation polymerization techniques will be used. After the investigation of the electrochemical, optical and thermal properties of the obtained polymeric materials, studies for the industrial and technological applications (electrochromic devices and light emitting diodes (LEDs)) will be done at Atılım University and METU by experienced teams in the last two years of the project. When the materials designed in the project are moved successfully to the industrial fields such as electrochromic devices and LED applications, it will be brought to a solution to an industrial problem by using carborane chemicals. As a result, it will be the primary purpose and goal of our project to overcome the problem faced by industrial areas (electrochromic devices and LEDs) with the products based on special carboranes, which can be synthesized in our country.Research Project Donör-akseptör Düzeninde Yeni Bir Bileşik Grubununtasarımı, Sentezi ve İletken Polimerlerinin Uygulama AlanlarıDonor-acceptor-based electrochromic polymers, unknown in the literature, were synthesized and the optical and electrochemical properties of these materials were examined. In this study, in which both the donor effect and the acceptor effect were examined, soluble and processable materials with colors such as green, blue, cyan and black, although very few in number in the literature, were synthesized which are indispensable for their application areas. Necessary characterization studies have been carried out for the anticipated technological applications.Research Project Plastikleştirilmiş Poli(laktik Asit)’in Alev Dayanımının Fosfor Bazlı Katkı Maddeleri ile GeliştirilmesiThe aim of this study is to improve the flame resistance and toughness of PLA by adding small amounts of different flame retardant additives and plasticizers at the same time. Poly(ethylene glycol) (PEG) was used as a plasticizer. Phosphate-based chemicals as flame retardant additives; ammonium polyphosphate (APP), boron phosphate (BP) and tri-phenyl phosphate (TPP) were used. Within the scope of the project, the synergistic effects of the double and triple compositions of these flame retardant additives were also examined. The mixtures are produced by melt blending and injection molding methods. The effect of the type and composition of flame retardant additives on the properties of PLA composites was determined by various mechanical, thermal and flammability tests.Research Project Preparation Of Magnetic Nanoparticles Which Enable The Use Of 18f-fdg As Multi-modal İmaging Agents İn Pet-mrı Applications/18f-fdg Nin Pet-mr Görüntüleme Uygulamalarında Multi-modal Görüntüleme Ajanı Olarak Kullanılmasına Yönelik Manyetik Nanoparçacıkların HazırlanmasıIt is becoming increasingly evident that PET-MRI multi-modal imaging systems have great potential in practical medicine and for basic scientific research. Consequently there is a wide interest in developing proper imaging agents for these applications. Superparamagnetic iron oxide (SPIO) nanoparticles are already, extensively, being used as MRI contrast agents. The labeling of these nanoparticles with radioactive isotopes provides a new generation for MRI agents. Combination of the required properties, in the body of the same sample for both measurement techniques, ensures that both images are coming from the same spot and simultaneously. This approach provides more accurate and reliable data for diagnosis and treatment of the illness. One of the candidates of the applicable radioactive isotopes is 18F, an easily available one and is being produced in our country. However its chemical binding to delivery agents requires several steps of exhaustive chemical treatments. A laboratory/firm which tends to fabricate iron oxide nanoparticles labeled with 18F should reconstruct a new manufacturing plant, which needs a laborious and a quite expensive operation. Instead, a new process, which can convert already available PET contrast agents into PET-MRI agents without requiring any special expertise, would be more practical and economical.Research Project Alan Özelinde Sosyalleştirme Yaklaşımı Çerçevesinde Etkili Ebeveynlik: Annenin Duygusal Erişilebilirliği ile Gelişimsel Çocuk Çıktıları Arasındaki İlişkiThis study aims to examine effective parenting within the framework of the domains-of_x0002_socialization approach. Three separate studies were carried out. In the first study, Domain_x0002_Specific Parenting Interview (DSPI) was developed to measure parenting quality in different socialization domains and its psychometric properties were examined. The deductive content analysis of the DSPI was carried out in the second study. In the third study, the replicability of the first study was tested, the interactions between different socialization domains were examined qualitatively, and the relations of mothers' knowledge on effective parenting and the quality of their parenting behaviors with developmental child outcomes were examined. The participants of the first study consisted of 82 mothers with children between 35-76 months. The participants of the second study consisted of 50 mothers, which were randomly selected from the data set of the first study. The participants of the third study consisted of 141 mothers and fathers, who have children aged between 47-72 months. The findings of the first study provided evidence that DSPI is a valid and reliable measurement tool. The qualitative findings of the second study showed that the domains-of-socialization approach and the daily life interactions of mother-child dyads were mostly consistent. The third study showed that the quality of parenting behaviors in different socialization domains were related to various child outcomes through emotion regulation and inhibitory control.Research Project Kimyasal ışıl-ışıma özelliğine sahip heterosiklik monomerlerin ve iletken polimerlerinin sentezlenmesi ve uygulama alanlarıA new group of compounds with chemiluminescence properties were designed and synthesized, and after their identification, their behavior towards metal ions was examined. Some of these compounds, which are likely to be used in both analytical chemistry and forensic science, have been successfully polymerized by electrochemical methods and their optical and electrochemical properties have been identified.Research Project Kurşun İçermeyen Yeni Nesil Primer Patlayıcı Tasarımı, Sentezi ve KarakterizasyonuMercury fulminate, lead azide and lead styphnate have been used as primary explosives for a long time. They are very good initiatory explosives, however, they have some serious drawbacks such as thermal, hydrolytic, chemical instability, highly sensitive to light, high toxicity of the compounds themselves, high sensitivity to mechanical stimuli. Today, improvement on the existing primary explosives is essential to find materials without heavy metals with safer production line and more efficient use compared to the present ones. The main aim of this study is to synthesize and explore the initiating performance of novel energetic organic and metallic compounds, which lead to providing the similar or even better performance with lower toxicity. For this purpose, 5-(kloronitrometil)-4-nitro-1H-imidazol ligand and its cobalt, copper, iron and zinc complexes in different geometries were synthesized. The characterization of the complexes was elucidated by elemental analysis, ESI-MS, IR and 1H-NMR spectroscopy techniques. The geometric and electronic properties of the complexes were determined using gas phase density functional theory calculations. Then, the explosive properties of the energetic materials obtained were studied with theoretical methods. The thermal stability of the materials was investigated by TG-TA methods. Explosion safety tests of the two most suitable complexes having exothermic energy profile were completed in the form of service procurement. The results obtained showed that the prepared complexes have very high thermal stability, they do not show the ability to be a primary explosive. However, the complexes having exothermic properties can be used as propelling power, and the complexes having endothermic properties can be used as additives to increase thermal stability against impact and friction in high energy rocket fuels.Research Project Dolgu Maddesi Eklenmesiyle İletken Polimer Kompozitlerinin HazırlanmasıWithin the scope of the project, conductive polymer composites with uniform filler distribution were produced by mixing thermoplastic polymers and carbon-based conductive fillers in molten form. Electrical, mechanical, thermal and morphological characterization of the produced composites were carried out. In the project experiments, conductive polymer composites of different compositions were prepared by mixing high-density polyethylene (HDPE), Nylon 6, Polypropylene (PP), Poly(ethylene thermthalate) (PET) polymer matrices, carbon black and multi-walled carbon nanotube particles in a twin-screw extruder. Test specimens were prepared using pressure and injection molding devices. The electrical properties of the samples were determined using two- and four-point probe conductivity measurement methods. During the mechanical characterization processes, tensile and impact strength tests were applied to the composites. Thermal properties were examined using DSC (diffrential scanning calorimetry) device. Morphological features were examined by SEM (scanning electron microscope). The electrical conductivity of insulating thermoplastic polymers has been reduced to the semiconductor level. The lowest critical concentration value (0.25% carbon nanotube by weight) was obtained in the PET-carbon nanotube composite system. The mechanical properties of composites have changed with the addition of fillers. The best improvement in mechanical properties was observed in PP-based composites. In general, as the amount of filler in the composites increased, the percentage of crystallization decreased.Research Project Quorum Sensing Inhibitör Özelliği Gösteren Yeni Moleküllerin Sentezi ve Çevreci Hidrojel Boya Sisteminde KullanımıBacteria present in the seawater quickly form a biofouling on the surfaces immersed in it. This process starts with the adhesion of organic nutrients such as protein and carbohydrates to the surface in the first seconds. Bacteria adhere to the nutrient film on the surface and form a protective biofilm of proteins and polysaccharides around them. The biological fouling process continues with the adhesion and development of diatoms (microalgae), macroalgae spores and macroorganism larvae such as of mussels. However, this sequential model is not valid in all cases. Biological fouling limits the maneuverability of water vehicles, increases fuel consumption and greenhouse gas emissions. Therefore, antifouling methods are important in terms of economy and environment issues. One of the methods to prevent microfouling on surfaces is to prevent communication between bacteria. Bacteria communicate with each other through "Quorum Sensing" (QS) molecules to permanently attach to surfaces. Gram-negative bacteria use acylated homoserine lactone (AHL) molecules for QS communication. Molecules resembling AHL have the potential to inhibit QS. Hydrogels with a three-dimensional polymer network are also considered promising coatings with high antifouling performances against marine organisms. The super hydrophilic property of hydrogel materials enables them to absorb large amounts of water into three-dimensional polymeric networks and form a hydrated layer on their surface, which can prevent the adhesion of micro or macroorganisms. For these reasons, in order to solve the problem of biological fouling within the scope of the proposed project, it is aimed to synthesize and characterize new QS analogs that will prevent bacteria from forming biofilms and settling on surfaces. As a result of the bacterial tests, the two compounds with the best antibiofilm properties will be used as biocides, and a water-based hydrogel paint formula with anti-QS properties will be developed. With the hydrogel technology, it is aimed to significantly reduce the friction force, fuel consumption and emissions together with the biofouling on the ship surface. The hydrogel paint designed within the scope of the project is water based, self-curing, can be easily applied to a ship surface by brushing or spraying and can be produced in powder form. Environmentalist methods were chosen in both synthesis stages. The use of organic solvents that cause volatile organic compounds (VOCs) to be released into the atmosphere is avoided.
